Special Issue "Microbial Diversity and Microbial Resistance"

A special issue of Biology (ISSN 2079-7737). This special issue belongs to the section "Microbiology".

Deadline for manuscript submissions: 31 March 2023 | Viewed by 37824

Special Issue Editors

Dr. Chrissoula Voidarou
E-Mail Website
Guest Editor
Department of Agriculture, School of Agriculture, University of Ioannina, 47100 Arta, Greece
Interests: microbiology; microbial ecology; public health; food-borne diseases; food technology; food safety; nutrients; fermented foods; lactic acid bacteria; antimicrobial resistance
Special Issues, Collections and Topics in MDPI journals
Prof. Athina S. Tzora
E-Mail Website
Guest Editor
Dean of the School of Agriculture, Department of Agriculture, University of Ioannina, 47100 Arta, Greece
Interests: microbiology; immunology; food born diseases; food safety; fermented foods; Lactic Acid Bacteria; microbial resistance; selective breeding programs
Special Issues, Collections and Topics in MDPI journals
Dr. Georgios Rozos
E-Mail Website
Guest Editor
Veterinary Directorate, South Aegean Region, Ermoupolis, 84100 Syros, Greece
Interests: microbiology; food born diseases; food safety; nutrients; fermented foods; Lactic Acid Bacteria; microbial resistance; selective breeding programs

Special Issue Information

Dear Colleagues,

Resistance to antibiotics is a silent but salient pandemic. Projection models estimate that by 2030 perhaps as much as 10 million people per year will die globally due to resistant pathogens. Numerous reports describe and analyze the detrimental impact of resistant bacteria to human health. In the recent years, much knowledge has been accumulated in areas such as the use and abuse of antibiotics in humans and animals, the resistance of environmental microorganisms, and of course the presence of resistant microbes to various foods. However, certain aspects of the latter remain relatively unnoticed, despite their crucial importance, and one of them is the correlation of biodiversity with resistance to antibiotics. Are biologically diverse systems like foods capable of preventing or holding up the spread of microbial resistance? Does the level of biodiversity of microbial communities in foods inhibit or favor the resistance genes? These indicative questions set the frame of the topics of interest that will be covered in this Special Issue of Biology titled “Microbial Biodiversity and Microbial Resistance in Food.

Dr. Chrissoula Voidarou
Prof. Athina S. Tzora
Dr. Georgios Rozos
Guest Editors

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Keywords

  • bacterial biodiversity
  • resistance
  • antibiotics
  • antimicrobial resistance (AMR)
  • foods
  • genetic elements
  • genes

Published Papers (25 papers)

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Article
Characterization of Acinetobacter baumannii Isolated from Raw Milk
Biology 2022, 11(12), 1845; https://doi.org/10.3390/biology11121845 - 18 Dec 2022
Viewed by 827
Abstract
Acinetobacter baumannii (A. baumannii) is an opportunistic pathogen associated with nosocomial infections. In this study, 100 raw milk samples were collected from Qena, Egypt, and subjected to conventional and molecular assays to determine the presence of A. baumannii and investigate their antimicrobial resistance [...] Read more.
Acinetobacter baumannii (A. baumannii) is an opportunistic pathogen associated with nosocomial infections. In this study, 100 raw milk samples were collected from Qena, Egypt, and subjected to conventional and molecular assays to determine the presence of A. baumannii and investigate their antimicrobial resistance and biofilm formation. Our findings revealed that, among the 100 samples, Acinetobacter spp. were found in 13 samples based on CHROM agar results. We further characterized them using rpoB and 16S-23SrRNA sequencing and gyrB multiplex PCR analysis and confirmed that 9 out of the 13 Acinetobacter spp. isolates were A. baumannii and 4 were other species. The A. baumannii isolates were resistant to β-lactam drugs, including cefotaxime (44%), ampicillin-sulbactam and levofloxacin (33.3% for each), imipenem, meropenem and aztreonam (22.2% for each). We observed different antimicrobial resistance patterns, with a multi-antibiotic resistant (MAR) index ranging from 0.2 to 0.3. According to the PCR results, blaOXA-51 and blaOXA-23 genes were amplified in 100% and 55.5% of the A. baumannii isolates, respectively, while the blaOXA-58 gene was not amplified. Furthermore, the metallo-β-lactamases (MBL) genes blaIMP and blaNDM were found in 11.1% and 22.2% of isolates, respectively, while blaVIM was not amplified. Additionally, eight A. baumannii isolates (88.8%) produced black-colored colonies on Congo red agar, demonstrating their biofilm production capacity. These results showed that, besides other foodborne pathogens, raw milk should also be examined for A. baumannii, which could be a public health concern. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Insights into Bacterial Communities and Diversity of Mangrove Forest Soils along the Upper Gulf of Thailand in Response to Environmental Factors
Biology 2022, 11(12), 1787; https://doi.org/10.3390/biology11121787 - 08 Dec 2022
Viewed by 398
Abstract
The comprehensive data for the dynamic adaptation of bacterial community structure in response to environmental factors is important for the maintenance of the mangrove ecosystem. This aspect was investigated with soils and surface water from six mangrove forests in six provinces along the [...] Read more.
The comprehensive data for the dynamic adaptation of bacterial community structure in response to environmental factors is important for the maintenance of the mangrove ecosystem. This aspect was investigated with soils and surface water from six mangrove forests in six provinces along the Upper Gulf of Thailand shoreline. Mangrove soils were variable with respect to pH (acidic to slightly alkaline) and had low amounts of organic matter (OM). Illumina next-generation sequencing attested that the number of observed species as well as the bacterial diversity and richness among all sites were not significantly different. The gamma-, alpha-Proteobacteria, Desulfobacteria, Bacteroidia, Anaerolineae, Bathyarchaeia, Acidobacteriae, Nitrososphaeria, Clostridia, and Thermoplasmata were more abundant bacterial classes present in all sites. Soil OM was the major factor that mostly modulated the bacterial community structure, while salinity influenced the number of observed species and bacterial richness. These results provide informative data on the bacterial community, in response to both environmental factors and heavy metal pollutants, that is prominent for sustainable development and management of mangrove forests. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Antimicrobial and Methicillin Resistance Pattern of Potential Mastitis-Inducing Staphylococcus aureus and Coagulase-Negative Staphylococci Isolates from the Mammary Secretion of Dairy Goats
Biology 2022, 11(11), 1591; https://doi.org/10.3390/biology11111591 - 29 Oct 2022
Cited by 1 | Viewed by 706
Abstract
Staphylococcus spp. is an important mastitis-inducing zoonotic pathogen in goats and is associated with antimicrobial resistance (AMR). The objectives of this study were to determine the prevalence and composition of staphylococci in individual mammary secretion (MS) samples of clinically healthy goats and to [...] Read more.
Staphylococcus spp. is an important mastitis-inducing zoonotic pathogen in goats and is associated with antimicrobial resistance (AMR). The objectives of this study were to determine the prevalence and composition of staphylococci in individual mammary secretion (MS) samples of clinically healthy goats and to evaluate the phenotypic AMR pattern and the presence of methicillin resistance in the Staphylococcus spp. strains. Staphylococcus spp. isolates (n = 101) from the MS samples (n = 220) were identified to species level using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The antimicrobial susceptibility testing included a disk diffusion assay and the determination of the minimum inhibitory concentrations (MIC) of resistant strains (n = 46). Presumptive methicillin-resistant strains (n = 9) were assessed for the presence of mecA, mecC and SCCmec/orfx genes. Staphylococcus spp. isolates were recovered from 45.9% of the MS samples, of which, 72.3% was identified as coagulase-negative staphylococci (CoNS), with the remaining being Staphylococcus aureus. CoNS and S. aureus were most commonly resistant to ampicillin (56.2% and 57.1%, respectively), penicillin (26.0% and 39.3%, respectively), amoxicillin (26 % and 25 %, respectively) and cephalexin (12.3% and 25%, respectively) in the disk diffusion method. CoNS exhibited a broader AMR pattern and a higher percentage of resistant strains than S. aureus in the disk diffusion and MIC methods. Of the nine oxacillin- and cefoxitin-resistant strains, three S. aureus and five CoNS strains carried the mecA gene and, thus, were identified as methicillin-resistant. The mecC gene was not found in any of the studied strains. The presence of AMR and methicillin resistance in caprine S. aureus and CoNS poses a concern for animal and public health. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Didecyldimethylammonium Chloride- and Polyhexamethylene Guanidine-Resistant Bacteria Isolated from Fecal Sludge and Their Potential Use in Biological Products for the Detoxification of Biocide-Contaminated Wastewater Prior to Conventional Biological Treatment
Biology 2022, 11(9), 1332; https://doi.org/10.3390/biology11091332 - 09 Sep 2022
Cited by 2 | Viewed by 738
Abstract
Toxic shock caused by the discharge of biocide-contaminated fecal sludge (FS) from chemical toilets to conventional wastewater treatment plants (WWTP) can be a major problem in activated sludge operation. It is necessary to develop new environmental approaches to mitigate the toxicity of biocides [...] Read more.
Toxic shock caused by the discharge of biocide-contaminated fecal sludge (FS) from chemical toilets to conventional wastewater treatment plants (WWTP) can be a major problem in activated sludge operation. It is necessary to develop new environmental approaches to mitigate the toxicity of biocides in order to avoid degrading the performance of WWTP. “Latrina”, a chemical toilet additive containing didecyldimethylammonium chloride and polyhexamethylene guanidine, is widely used in environmentally safe toilet complexes (ESTC) on Russian railway trains to deodorize FS and control microbial activity. In this work, seven biocide-resistant bacterial strains were isolated and identified from the FS of ESTC. The values of the minimum inhibitory and bactericidal concentrations of biocides for the isolated strains were 4.5–10 times higher than for the collection microorganisms. The bacterium Alcaligenes faecalis DOS7 was found to be particularly resistant to “Latrina”, the minimum inhibitory concentration of which was almost 30 times higher than recommended for ESTC. Biological products based on isolated bacterial strains proved to be effective for FS biodegradation under both aerobic and anaerobic conditions. The results of the biochemical oxygen demand test and the newly developed disk-diffusion bioassay confirmed that isolated strains contribute to reducing toxicity of biocidal agents in FS. Hyper-resistance, non-pathogenicity, and potential plant growth-promoting ability make A. faecalis DOS7 promising for use in various biological products for wastewater treatment and bioremediation of soils contaminated with biocides, as well as in agriculture to increase plant productivity. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Distribution and Prevalence of Plant-Parasitic Nematodes of Turfgrass at Golf Courses in China
Biology 2022, 11(9), 1322; https://doi.org/10.3390/biology11091322 - 06 Sep 2022
Viewed by 734
Abstract
We sampled 127 turfgrass soil samples from 33 golf courses in NC, EC, and SC for plant-parasitic nematodes (PPNs). PPNs were extracted from soil samples using the shallow dish method and were identified at the genus or species levels with a combination of [...] Read more.
We sampled 127 turfgrass soil samples from 33 golf courses in NC, EC, and SC for plant-parasitic nematodes (PPNs). PPNs were extracted from soil samples using the shallow dish method and were identified at the genus or species levels with a combination of morphological and molecular methods. The results revealed 41 species of nematode belonging to 20 genera and 10 families. Nine genera are new records of PPNs associated with turfgrass in China. The PPNs show strong geographical distributions. Of the 20 genera, Helicotylenchus, Paratrichodorus, Hoplolaimus, Meloidogyne, Hemicriconemoides, and Mesocriconema showed higher infestation and frequency, and most of these genera had numbers in soil samples above established damage thresholds. Four golf courses had soil samples with PPNs > 30%, indicating the potential for nematode damage. The biodiversity indices H’, SR, J’, λ, and H2 showed significant differences among different regions and turfgrass species; H’, SR, J’, and H2 were significantly higher in EC than in NC and SC, while λ was lowest in EC. Creeping bentgrass had the highest H’, SR, J’, and H2 and the lowest λ in comparison with seashore paspalum and hybrid bermudagrass. These findings provide baseline information on the occurrence of turfgrass-associated PPNs in China, and have important implications for the effective management of PPNs causing damage on turfgrass. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Isolation, Physiological Characterization, and Antibiotic Susceptibility Testing of Fast-Growing Bacteria from the Sea-Affected Temporary Meltwater Ponds in the Thala Hills Oasis (Enderby Land, East Antarctica)
Biology 2022, 11(8), 1143; https://doi.org/10.3390/biology11081143 - 29 Jul 2022
Viewed by 986
Abstract
In this study, for the first time, we report the identification and characterization of culturable fast-growing bacteria isolated from the sea-affected temporary meltwater ponds (MPs) in the East Antarctica area of the Vecherny region (−67.656317, 46.175058) of the Thala Hills Oasis, Enderby Land. [...] Read more.
In this study, for the first time, we report the identification and characterization of culturable fast-growing bacteria isolated from the sea-affected temporary meltwater ponds (MPs) in the East Antarctica area of the Vecherny region (−67.656317, 46.175058) of the Thala Hills Oasis, Enderby Land. Water samples from the studied MPs showed alkaline pH (from 8.0 to 10.1) and highly varied total dissolved solids (86–94,000 mg/L). In total, twenty-nine bacterial isolates were retrieved from the studied MPs. The phylogenetic analysis based on 16S rRNA gene sequence similarities showed that the isolated bacteria belong to the phyla Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes and the twelve genera Pseudomonas, Shewanella, Acinetobacter, Sporosarcina, Facklamia, Carnobacterium, Arthrobacter, Brachybacterium, Micrococcus, Agrococcus, Leifsonia, and Flavobacterium. Most of the isolated bacteria were psychrotrophs and showed the production of one or more extracellular enzymes. Lipolytic and proteolytic activities were more prevalent among the isolates. Five isolates from the Actinobacteria phylum and one isolate from the Bacteroidetes phylum had strong pigmentation. Antibiotic susceptibility testing revealed that most of the isolates are resistant to at least one antibiotic, and seven isolates showed multi-resistance. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Prevalence and Antimicrobial Susceptibility of Bovine Mycoplasma Species in Egypt
Biology 2022, 11(7), 1083; https://doi.org/10.3390/biology11071083 - 20 Jul 2022
Cited by 2 | Viewed by 903
Abstract
Among many bovine Mycoplasma species (spp.), Mycoplasma bovis is recognized as a significant causative agent of respiratory diseases in cattle. In recent years, resistant M. bovis isolates, especially to fluoroquinolones, have been reported globally as a result of the extensive usage of antimicrobials [...] Read more.
Among many bovine Mycoplasma species (spp.), Mycoplasma bovis is recognized as a significant causative agent of respiratory diseases in cattle. In recent years, resistant M. bovis isolates, especially to fluoroquinolones, have been reported globally as a result of the extensive usage of antimicrobials in the treatment of bovine pneumonia. Therefore, the aim of this study is to investigate the prevalence and antimicrobial susceptibility patterns of bovine Mycoplasma spp. isolated from the respiratory tracts of cattle in Egypt and to assess the fluoroquinolones resistance in the recovered mycoplasma isolates via broth microdilution and conventional PCR techniques. Conventional phenotypic methods identified 128 mycoplasma isolates (32%) from 400 different samples, with M. bovis being the predominant spp. (61%), followed by M. bovirhinis (15%). Of note, mycoplasma isolates were rarely isolated from total healthy lung tissues (7/55, 12.7%), but they were frequently isolated from pneumonic lungs (31/45, 68.9%). All the examined mycoplasma isolates (n = 76) were sensitive to tilmicosin, tylosin, tulathromycin, spiramycin, and spectinomycin (100% each), while 60.5% and 43.4% of the examined isolates had high minimum inhibitory concentration (MIC) values to enrofloxacin and doxycycline, respectively. Three and two mycoplasma isolates with high enrofloxacin MICs were confirmed to be M. bovis and M. bovirhinis, respectively, by PCR assays. All molecularly confirmed mycoplasma isolates (n = 5) were positive for the gyrA gene (100%); meanwhile, three isolates (60%) were positive for the parC gene. In conclusion, our findings revealed alarming resistance to enrofloxacin and doxycycline antibiotics; thus, antimicrobial usage must be restricted and molecular techniques can help in the rapid detection of the resistant strains. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
What Is behind the Correlation Analysis of Diarrheagenic E. coli Pathotypes?
Biology 2022, 11(7), 1004; https://doi.org/10.3390/biology11071004 - 02 Jul 2022
Cited by 1 | Viewed by 902
Abstract
The treatment failure recorded among patients and animals infected with diarrheagenic Escherichia coli (DEC) was increased due to the presence of specific virulence markers among these strains. These markers were used to classify DEC into several pathotypes. We analyzed the correlations between DEC [...] Read more.
The treatment failure recorded among patients and animals infected with diarrheagenic Escherichia coli (DEC) was increased due to the presence of specific virulence markers among these strains. These markers were used to classify DEC into several pathotypes. We analyzed the correlations between DEC pathotypes and antimicrobial resistances, the existence of virulence genes, serotypes, and hosts. The ETEC pathotype was detected with a high prevalence rate (25%). Moreover, the ETEC and EPEC pathotypes were highly associated with human infections in contrast to the EIEC and EAEC phenotypes, which were commonly recognized among animal isolates. Interestingly, the antimicrobial resistance was affected by E. coli pathotypes. With the exception of EIEC and STEC, imipenem represented the most effective antibiotic against the other pathotypes. There were fixed correlations between the DEC pathotypes and the presence of virulence markers and hosts; meanwhile, their correlation with serotypes was variable. Additionally, the vast majority of our isolates were highly diverse, based on both phenotypic and ERIC molecular typing techniques. Our promising results gave a clear indication for the heterogeneity and weak clonality of DEC pathotypes in Egypt, which can be utilized in the evaluation of the current therapeutic protocols and infection control guidelines. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Brain Natriuretic Peptide (BNP) Affects Growth and Stress Tolerance of Representatives of the Human Microbiome, Micrococcus luteus C01 and Alcaligenes faecalis DOS7
Biology 2022, 11(7), 984; https://doi.org/10.3390/biology11070984 - 29 Jun 2022
Cited by 1 | Viewed by 952
Abstract
Brain natriuretic peptide (BNP) is secreted by the ventricles of the heart during overload to signal heart failure. Slight bilateral skin itching induced by BNP has been associated with response activity of the skin microbiota. In this work, we studied the effect of [...] Read more.
Brain natriuretic peptide (BNP) is secreted by the ventricles of the heart during overload to signal heart failure. Slight bilateral skin itching induced by BNP has been associated with response activity of the skin microbiota. In this work, we studied the effect of 25–250,000 pg BNP/mL on the growth, long-term survival, and stress (H2O2, antibiotics, salinity, heat and pH shock) resistance of human symbiont bacteria: Gram-positive Micrococcus luteus C01 and Gram-negative Alcaligenes faecalis DOS7. The effect of BNP turned out to be dose-dependent. Up to 250 pg BNP/mL made bacteria more stress resistant. At 2500 pg BNP/mL (heart failure) the thermosensitivity of the bacteria increased. Almost all considered BNP concentrations increased the resistance of bacteria to the action of tetracycline and ciprofloxacin. Both bacteria survived 1.3–1.7 times better during long-term (up to 4 months) storage. Our findings are important both for clinical medical practice and for practical application in other areas. For example, BNP can be used to obtain stress-resistant bacteria, which is important in the collection of microorganisms, as well as for the production of bacterial preparations and probiotics for cosmetology, agriculture, and waste management. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Isolation of Listeria ivanovii from Bulk-Tank Milk of Sheep and Goat Farms—From Clinical Work to Bioinformatics Studies: Prevalence, Association with Milk Quality, Antibiotic Susceptibility, Predictors, Whole Genome Sequence and Phylogenetic Relationships
Biology 2022, 11(6), 871; https://doi.org/10.3390/biology11060871 - 06 Jun 2022
Cited by 1 | Viewed by 1205
Abstract
A cross-sectional study was performed in 325 sheep and 119 goat dairy farms in Greece. Samples of bulk-tank milk were examined by standard microbiological techniques for Listeria spp. Listeria monocytogenes was isolated from one (0.3%) and Listeria ivanovii from three (0.9%) sheep farms. [...] Read more.
A cross-sectional study was performed in 325 sheep and 119 goat dairy farms in Greece. Samples of bulk-tank milk were examined by standard microbiological techniques for Listeria spp. Listeria monocytogenes was isolated from one (0.3%) and Listeria ivanovii from three (0.9%) sheep farms. No associations between the isolation of L. monocytogenes or L. ivanovii and milk quality were found. No resistance to antibiotics was identified. Three variables emerged as significant predictors of isolation of the organism: the presence of pigs, low average relative humidity and a high number of ewes on the farm. The three L. ivanovii isolates were assessed in silico for identification of plasmids, prophages, antibiotic resistance genes, virulence factors, CRISPRs and CAS genes. Phylogenetic analysis using the core genome revealed that the three strains belonged to the L. ivanovii subsp. ivanovii branch and were especially close to the PAM 55 strain. All strains of the branch appeared to be very similar, with the distance between them being small. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Serological Variety and Antimicrobial Resistance in Salmonella Isolated from Reptiles
Biology 2022, 11(6), 836; https://doi.org/10.3390/biology11060836 - 29 May 2022
Cited by 1 | Viewed by 1199
Abstract
Salmonella enterica is one of the best adapted bacterial pathogens causing infections in a wide variety of vertebrate species. The aim of this study was to investigate the prevalence of Salmonella in different reptile species and to evaluate their serological variety and [...] Read more.
Salmonella enterica is one of the best adapted bacterial pathogens causing infections in a wide variety of vertebrate species. The aim of this study was to investigate the prevalence of Salmonella in different reptile species and to evaluate their serological variety and patterns of antimicrobial resistance. In total, 97 samples from 25 wild and domesticated reptile species were investigated in Lithuania. Serological variety, as well as phenotypical and genotypical resistance to antimicrobials, were investigated. Fifty isolates of Salmonella were obtained from the ninety-seven tested samples (51.5%; 95% CI 41.2–61.2). A significantly higher prevalence of Salmonella was detected in domesticated individuals (61.3%; 95% CI 50.0–71.5) compared with wild ones (18.2%; 95% CI 7.3–38.5). All isolates belonged to a single species, Salmonella enterica. Results demonstrated that reptiles carry a large variety of Salmonella serovars. Thirty-four isolates (68%) of Salmonella were resistant to at least one antimicrobial drug. The most frequent resistance of the isolates was to streptomycin (26%), cefoxitin, gentamicin, tetracycline and chloramphenicol (16%). Genes encoding resistance to tetracyclines, aminoglycosides, sulphonamides and trimethoprim were detected. No integrons that are associated with horizontal gene transfer were found. Data obtained provided knowledge about the adaptation of Salmonella in reptiles. Healthy individuals, irrespective of their origin, often carry Salmonella, including multi-resistant strains. Due to its large serological diversity, zoonotic potential and antimicrobial resistance, Salmonella in reptiles poses a risk to other animals and humans. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Enterococcus raffinosus, Enterococcus durans and Enterococcus avium Isolated from a Tertiary Care Hospital in Romania—Retrospective Study and Brief Review
Biology 2022, 11(4), 598; https://doi.org/10.3390/biology11040598 - 14 Apr 2022
Cited by 5 | Viewed by 1924
Abstract
(1) Background: This paper aims to provide a description of non-faecalis non-faecium enterococci isolated from a tertiary care hospital in Romania and to briefly review the existing literature regarding the involvement of Enterococcus raffinosus, Enterococcus durans and Enterococcus avium in human infections [...] Read more.
(1) Background: This paper aims to provide a description of non-faecalis non-faecium enterococci isolated from a tertiary care hospital in Romania and to briefly review the existing literature regarding the involvement of Enterococcus raffinosus, Enterococcus durans and Enterococcus avium in human infections and their antimicrobial resistance patterns; (2) Methods: We retrospectively analyzed all Enteroccocus species isolated from the “Prof. Dr. O. Fodor” Regional Institute of Gastroenterology and Hepatology from Cluj-Napoca during one year focusing on non-faecalis non-faecium Enterococci. A brief review of the literature was performed using case reports involving Enterococcus raffinosus, Enterococcus durans and Enterococcus avium; (3) Results: Only 58 out of 658 Enteroccocus isolates were non-faecalis non-faecium and met the inclusion criteria. These species were isolated more often (p < 0.05) from the surgical ward from mixed etiology infections with E. coli. In our review, we included 39 case reports involving E. raffinosus, E. durans and E. avium; (4) Conclusions: Isolation of non-faecalis non-faecium enterococci displays an emerging trend with crucial healthcare consequences. Based on the analysis of the case reports, E. avium seems to be involved more often in neurological infections, E. durans in endocarditis, while E. raffinosus displays a more heterogenous distribution. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Clostridium perfringens Associated with Foodborne Infections of Animal Origins: Insights into Prevalence, Antimicrobial Resistance, Toxin Genes Profiles, and Toxinotypes
Biology 2022, 11(4), 551; https://doi.org/10.3390/biology11040551 - 01 Apr 2022
Cited by 4 | Viewed by 1988
Abstract
Several food-poisoning outbreaks have been attributed to Clostridium perfringens (C. perfringens) worldwide. Despite that, this crisis was discussed in a few studies, and additional studies are urgently needed in this field. Therefore, we sought to highlight the prevalence, antimicrobial resistance, toxin [...] Read more.
Several food-poisoning outbreaks have been attributed to Clostridium perfringens (C. perfringens) worldwide. Despite that, this crisis was discussed in a few studies, and additional studies are urgently needed in this field. Therefore, we sought to highlight the prevalence, antimicrobial resistance, toxin profiles, and toxinotypes of C. perfringens isolates. In this study, 50 C. perfringens isolates obtained from 450 different animal origin samples (beef, chicken meat, and raw milk) were identified by phenotypic and genotypic methods. The antimicrobial susceptibility results were surprising, as most of the isolates (74%) showed multidrug-resistant (MDR) patterns. The phenotypic resistance to tetracycline, lincomycin, enrofloxacin, cefoxitin/ampicillin, and erythromycin was confirmed by the PCR detections of tet, lnu, qnr, bla, and erm(B) genes, respectively. In contrast to the toxinotypes C and E, toxinotype A prevailed (54%) among our isolates. Additionally, we found that the genes for C. perfringens enterotoxin (cpe) and C. perfringens beta2 toxin (cpb2) were distributed among the tested isolates with high prevalence rates (70 and 64%, respectively). Our findings confirmed that the C. perfringens foodborne crisis has been worsened by the evolution of MDR strains, which became the prominent phenotypes. Furthermore, we were not able to obtain a fixed association between the toxinotypes and antimicrobial resistance patterns. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Detection of Carbapenem Resistance of Proteus mirabilis Strains Isolated from Foxes, Raccoons and Minks in China
Biology 2022, 11(2), 292; https://doi.org/10.3390/biology11020292 - 11 Feb 2022
Viewed by 1110
Abstract
Proteus mirabilis, an opportunistic pathogen, is found to be an emerging threat to both animals and humans for a variety of infections. However, the characteristics of P. mirabilis infections from foxes, raccoons and minks remain unclear. In this context, we identified the [...] Read more.
Proteus mirabilis, an opportunistic pathogen, is found to be an emerging threat to both animals and humans for a variety of infections. However, the characteristics of P. mirabilis infections from foxes, raccoons and minks remain unclear. In this context, we identified the antibiotic resistance genes and virulence genes of P. mirabilis isolates from foxes, raccoons and minks in China. Most isolates showed resistance to florfenicol (90.57%), trimethoprim-sulfamethoxazole (73.58%), and imipenem (71.70%). A total of 73.58% of isolates were resistant to antibiotics from at least three or more classes, and were categorized as multi-drug resistant. A total of 33.33% of the isolates were resistant to antibiotics from seven classes. The most prevalent resistant were sul1 (94.34%), followed by floR, blaTEM, aac(6’)Ib-cr and blaOXA-1 with the detection rate of 88.68%, 83.02%, 71.70% and 60.38%, respectively. Among the 51 P. mirabilis isolates that were resistant to beta-lactam antibiotics, all isolates carried at least one beta-lactam gene. In addition, blaNDM and blaOXA-24 genes were firstly reported in carbapenem-resistant P. mirabilis isolates from foxes, raccoons and minks. All isolates exhibited the virulence genes ureC, zapA, pmfA, atfA and mrpA. P. mirabilis isolates carrying all detected 10 virulence genes from different animal species showed different lethal abilities in a G. mellonella larvae model. More importantly, the profiles of antibiotic resistance genes of isolates from fur animals and the environment were generally similar, and phylogenetic analysis showed that the P. mirabilis isolates from farm environment samples may have close relatedness with that from animals. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Evaluation of Different Techniques, including Modified Atmosphere, under Vacuum Packaging, Washing, and Latilactobacillus sakei as a Bioprotective Agent, to Increase the Shelf-Life of Fresh Gutted Sea Bass (Dicentrarchus labrax) and Sea Bream (Sparus aurata) Stored at 6 ± 2 °C
Biology 2022, 11(2), 217; https://doi.org/10.3390/biology11020217 - 29 Jan 2022
Cited by 2 | Viewed by 1428
Abstract
Fish meat is very perishable because of indigenous and microbial enzymes, which determine spoilage and shelf life. The deterioration processes, which lead to an important, sequential, and progressive modification of the initial state of freshness, are fast and depend on rearing, harvesting, slaughtering, [...] Read more.
Fish meat is very perishable because of indigenous and microbial enzymes, which determine spoilage and shelf life. The deterioration processes, which lead to an important, sequential, and progressive modification of the initial state of freshness, are fast and depend on rearing, harvesting, slaughtering, handling, and storage conditions. Usually, the shelf life of gutted fish stored at 4 ± 2 °C under vacuum packaging (VP—1.0 bar) and modified atmosphere packaging (MAP, 70% N2, <1% O2, 30% CO2) is approximately 9 days. The aim of this work was to improve the shelf life and preserve the microbiological and sensory quality of farmed gutted sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) using different methods, including VP, MAP, and bioprotective culture containing Latilactobacillus sakei, until 12–14 days. Microbiological, physicochemical, and sensory quality indices were monitored to confirm the effectiveness of biopreservation on product quality during proper refrigeration (4 ± 2 °C) or abuse (6 ± 2 °C, simulating supermarkets and consumer fridges) storage period. Considering the quality indexes represented by Enterobacteriaceae, total volatile nitrogen (TVB-N), and malonaldehyde concentrations (TBARS) and the sensorial analysis, the VP samples were more acceptable than the MAP fish, even though the shelf-life of the VP and MAP fish was similar at about 12 days. The second phase of the work was to evaluate the shelf-life of both VP fish stored at 6 ± 2 °C, which simulates the normal abuse temperature of supermarkets or consumer fridges. Data confirmed the previous results and demonstrated, despite the abuse temperature of storage, a shelf-life of about 12 days. Finally, the third phase consisted of prolonging the shelf life until 14 days of storage at 6 ± 2 °C by washing the gutted sea bass and sea bream in a suspension of bioprotective starter (7 log CFU/mL) with or without the addition of dextrose (0.1%) and by VP packaging. The bioprotective culture reduced the growth of spoilage microorganisms. Consequently, the total volatile nitrogen (TVB-N) concentration in both fish species was low (<35 mg N/100 g). Nonprofessional and untrained evaluators confirmed the acceptability of the inoculated samples by sensorial analysis. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
Article
Mammaliicoccus spp. from German Dairy Farms Exhibit a Wide Range of Antimicrobial Resistance Genes and Non-Wildtype Phenotypes to Several Antibiotic Classes
Biology 2022, 11(2), 152; https://doi.org/10.3390/biology11020152 - 18 Jan 2022
Cited by 2 | Viewed by 1183
Abstract
Mammaliicocci might play a major role in antimicrobial resistance (AMR) gene transmission between organisms of the family Staphylococcaceae, such as the potentially pathogenic species Staphylococcus aureus. The interest of this study was to analyze AMR profiles of mammaliicocci from German dairy [...] Read more.
Mammaliicocci might play a major role in antimicrobial resistance (AMR) gene transmission between organisms of the family Staphylococcaceae, such as the potentially pathogenic species Staphylococcus aureus. The interest of this study was to analyze AMR profiles of mammaliicocci from German dairy farms to evaluate the AMR transmission potential. In total, 65 mammaliicocci isolates from 17 dairy farms with a history of MRSA detection were analyzed for AMR genotypes and phenotypes using whole genome sequencing and antimicrobial susceptibility testing against 19 antibiotics. The various genotypic and phenotypic AMR profiles of mammaliicocci from German dairy farms indicated the simultaneous occurrence of several different strains on the farms. The isolates exhibited a non-wildtype phenotype to penicillin (58/64), cefoxitin (25/64), chloramphenicol (26/64), ciprofloxacin (25/64), clindamycin (49/64), erythromycin (17/64), fusidic acid (61/64), gentamicin (8/64), kanamycin (9/64), linezolid (1/64), mupirocin (4/64), rifampicin (1/64), sulfamethoxazol (1/64), streptomycin (20/64), quinupristin/dalfopristin (26/64), tetracycline (37/64), tiamulin (59/64), and trimethoprim (30/64). Corresponding AMR genes against several antimicrobial classes were detected. Linezolid resistance was associated with the cfr gene in the respective isolate. However, discrepancies between genotypic prediction and phenotypic resistance profiles, such as for fusidic acid and tiamulin, were also observed. In conclusion, mammaliicocci from dairy farms may carry a broad variety of antimicrobial resistance genes and exhibit non-wildtype phenotypes to several antimicrobial classes; therefore, they may represent an important source for horizontal gene transfer of AMR genes to pathogenic Staphylococcaceae. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
The Oleaginous Yeast Metschnikowia pulcherrima Displays Killer Activity against Avian-Derived Pathogenic Bacteria
Biology 2021, 10(12), 1227; https://doi.org/10.3390/biology10121227 - 24 Nov 2021
Cited by 3 | Viewed by 1266
Abstract
Metschnikowia pulcherrima is a non-conventional yeast with potential to be used in biotechnological processes, especially those involving low-cost feedstock exploitation and biocontrol applications. The combination of traits that supports these industrial applications in M. pulcherrima also makes it an attractive option to study [...] Read more.
Metschnikowia pulcherrima is a non-conventional yeast with potential to be used in biotechnological processes, especially those involving low-cost feedstock exploitation and biocontrol applications. The combination of traits that supports these industrial applications in M. pulcherrima also makes it an attractive option to study in the context of livestock health. In this study, we examined the specific interactions between M. pulcherrima and multiple avian pathogenic bacteria. We tested individual bacteria–yeast interactions and bacterial combinations in both solid and liquid media and in variable nutrient environments. Across multiple isolates of M. pulcherrima, we observed different levels of antimicrobial activity, varying from supporting the growth of competing bacteria through suppression and bacterial killing, and we found that these responses varied depending on the bacterial strains and media. We identified multiple molecular routes, including proteins produced by M. pulcherrima strains, that acted to control these microbial interactions. Furthermore, protein screening revealed that M. pulcherrima strains were induced to produce proteins specifically when exposed to bacterial strains, suggesting that fine-tuned mechanisms allow M. pulcherrima to function as a potential lynchpin in a microbial community. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Antibiotic Resistance of Staphylococci from Bulk-Tank Milk of Sheep Flocks: Prevalence, Patterns, Association with Biofilm Formation, Effects on Milk Quality, and Risk Factors
Biology 2021, 10(10), 1016; https://doi.org/10.3390/biology10101016 - 09 Oct 2021
Cited by 2 | Viewed by 1231
Abstract
The objectives of this work were to study prevalence and characteristics of resistance to antibiotics of staphylococcal isolates from the bulk-tank milk of sheep flocks across Greece, to assess possible associations of the presence of antibiotic resistance with the quality of milk in [...] Read more.
The objectives of this work were to study prevalence and characteristics of resistance to antibiotics of staphylococcal isolates from the bulk-tank milk of sheep flocks across Greece, to assess possible associations of the presence of antibiotic resistance with the quality of milk in these flocks and to evaluate flock-related factors potentially associated with antibiotic resistance among these isolates. A cross-sectional study was performed in 325 sheep flocks in Greece. Bulk-tank milk samples were collected for bacteriological examination; staphylococcal isolates were evaluated for resistance to 20 antibiotics. Oxacillin-resistant staphylococcal isolates, isolates resistant to any antibiotic, and multi-resistant isolates were recovered from 8.0%, 30.5%, and 12.0% of flocks, respectively. Of 232 isolates, 11.6% were resistant to oxacillin, 46.1% were resistant to at least one antibiotic, and 16.4% were multi-resistant. Resistance was seen more frequently among coagulase-negative (50.6%) than among Staphylococcus aureus (31.5%) isolates. Resistance was more frequent against penicillin and ampicillin (34.1% of isolates), clindamycin (17.7%), and fosfomycin (14.2%). An association was found between biofilm formation by staphylococci and resistance to fosfomycin. For recovery of oxacillin-resistant isolates, the lack of experience by farmers emerged as a significant factor; respective factors for the isolation of staphylococci resistant to any antibiotic or multi-resistant isolates were the early stage of the lactation period (0th–1st month) and the intensive management system applied in the flocks, respectively. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Genome Analysis of Acinetobacter lwoffii Strains Isolated from Permafrost Soils Aged from 15 Thousand to 1.8 Million Years Revealed Their Close Relationships with Present-Day Environmental and Clinical Isolates
Biology 2021, 10(9), 871; https://doi.org/10.3390/biology10090871 - 04 Sep 2021
Cited by 3 | Viewed by 2279
Abstract
Microbial life can be supported at subzero temperatures in permafrost up to several million years old. Genome analysis of strains isolated from permafrost provides a unique opportunity to study microorganisms that have not previously come into contact with the human population. Acinetobacter lwoffii [...] Read more.
Microbial life can be supported at subzero temperatures in permafrost up to several million years old. Genome analysis of strains isolated from permafrost provides a unique opportunity to study microorganisms that have not previously come into contact with the human population. Acinetobacter lwoffii is a typical soil bacterium that has been increasingly reported as hospital pathogens associated with bacteremia. In order to identify the specific genetic characteristics of ancient permafrost-conserved strains of A. lwoffii and their differences from present-day clinical isolates, we carried out a genome-wide analysis of five strains of A. lwoffii isolated from permafrost aged from 15 thousand to 1.8 million years. Surprisingly, we did not identify chromosomal genetic determinants that distinguish permafrost strains from clinical A. lwoffii isolates and strains from other natural habitats. Phylogenetic analysis based on whole genome sequences showed that permafrost strains do not form a separate cluster and some of them are most closely related to clinical isolates. The genomes of clinical and permafrost strains contain similar mobile elements and prophages, which indicates an intense horizontal transfer of genetic material. Comparison of plasmids of modern and permafrost strains showed that plasmids from the modern strains are enriched with antibiotic resistance genes, while the content of genes for resistance to heavy metals and arsenic is nearly the same. The thawing of permafrost caused by global warming could release new potentially pathogenic strains of Acinetobacter. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Profile of Bacterial Infections in COVID-19 Patients: Antimicrobial Resistance in the Time of SARS-CoV-2
Biology 2021, 10(9), 822; https://doi.org/10.3390/biology10090822 - 24 Aug 2021
Cited by 4 | Viewed by 2047
Abstract
The global onset of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus infections happened suddenly, hence imposing a rapid definition of effective therapeutic approaches. Antibiotics were included among the prophylactic agents because of both the similarity between SARS-CoV-2 and atypical pneumonia symptoms, and [...] Read more.
The global onset of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus infections happened suddenly, hence imposing a rapid definition of effective therapeutic approaches. Antibiotics were included among the prophylactic agents because of both the similarity between SARS-CoV-2 and atypical pneumonia symptoms, and the immune-modulating and anti-inflammatory properties of such drugs. Although, this approach could exacerbate the emergence of antimicrobial resistance. To evaluate the impact of the COVID-19 pandemic on the spread and characteristics of bacterial infections, as well as on the frequency of antimicrobial resistance, we investigated and compared clinical bacterial strains isolated in an Italian hospital from COVID-19 patients and non-COVID-19 patients during and before the COVID-19 outbreak. Data clearly indicate the impact of the COVID-19 pandemic on bacterial infections: not only some bacterial species were found in either COVID-19 positive or in COVID-19 negative patients, but isolates from COVID-19 patients also showed higher levels of antimicrobial resistance. Nevertheless, despite some bacterial species were isolated only before or over the pandemic, no differences were observed among the antimicrobial resistance levels. Overall, these results recapitulate the current situation of microbial infections and could also provide an overview of the impact of COVID-19 on bacterial pathogens spread and resistance. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
High Fecal Contamination and High Levels of Antibiotic-Resistant Enterobacteriaceae in Water Consumed in the City of Maputo, Mozambique
Biology 2021, 10(6), 558; https://doi.org/10.3390/biology10060558 - 20 Jun 2021
Cited by 8 | Viewed by 4024
Abstract
In the city of Maputo, Mozambique, food and water are often sold on the streets. Street water is packaged, distributed, and sold not paying attention to good hygienic practices, and its consumption is often associated with the occurrence of diarrheal diseases. Coincidentally, the [...] Read more.
In the city of Maputo, Mozambique, food and water are often sold on the streets. Street water is packaged, distributed, and sold not paying attention to good hygienic practices, and its consumption is often associated with the occurrence of diarrheal diseases. Coincidentally, the increase of diarrheal diseases promotes the inappropriate use of antibiotics that might cause the emergence of antibiotic-resistant bacterial strains. In this context, the present study aimed to assess the microbiological quality of water sold on the streets of Maputo, as well as the antibiotic resistance profile of selected Enterobacteriaceae isolates. The 118 water samples analyzed were from street home-bottled water (n = 81), municipal water distribution systems (tap water) (n = 25), and selected supply wells in several neighborhoods (n = 12). The samples were analyzed for total mesophilic microorganisms, fecal enterococci, fecal coliforms, Escherichia coli, and Vibrio spp. The results showed a high level of fecal contamination in all types of water samples. In home-bottled water, fecal coliforms were found in 88% of the samples, and E. coli in 66% of the samples. In tap water, fecal coliforms were found in 64%, and E. coli in 28% of the samples. In water from supply wells, fecal coliforms and E. coli were found in 83% of the samples. From 33 presumptive Vibrio spp. colonies, only three were identified as V. fluvialis. The remaining isolates belonged to Aeromonas spp. (n = 14) and Klebsiella spp. (n = 16). Of 44 selected Enterobacteriaceae isolates from water samples (28 isolates of E. coli and 16 isolates of Klebsiella spp.), 45.5% were not susceptible to the beta-lactams ampicillin and imipenem, 43.2% to amoxicillin, and 31.8% to amoxicillin/clavulanic acid. Regarding non-beta-lactam antibiotics, there was a high percentage of isolates with tolerance to tetracycline (52.3%) and azithromycin (31.8%). In conclusion, water in Maputo represents a risk for human health due to its high fecal contamination. This situation is made more serious by the fact that a relatively high percentage of isolates with multidrug resistance (40%) were found among Enterobacteriaceae. The dissemination of these results can raise awareness of the urgent need to reduce water contamination in Maputo and other cities in Mozambique. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
Article
Virulence Determinants of Colistin-Resistant K. pneumoniae High-Risk Clones
Biology 2021, 10(5), 436; https://doi.org/10.3390/biology10050436 - 14 May 2021
Cited by 5 | Viewed by 1583
Abstract
We proposed the hypothesis that high-risk clones of colistin-resistant K. pneumoniae (ColR-Kp) possesses a high number of virulence factors and has enhanced survival capacity against the neutrophil activity. We studied virulence genes of ColR-Kp isolates and neutrophil response in 142 patients with invasive [...] Read more.
We proposed the hypothesis that high-risk clones of colistin-resistant K. pneumoniae (ColR-Kp) possesses a high number of virulence factors and has enhanced survival capacity against the neutrophil activity. We studied virulence genes of ColR-Kp isolates and neutrophil response in 142 patients with invasive ColR-Kp infections. The ST101 and ST395 ColR-Kp infections had higher 30-day mortality (58%, p = 0.005 and 75%, p = 0.003). The presence of yersiniabactin biosynthesis gene (ybtS) and ferric uptake operon associated gene (kfu) were significantly higher in ST101 (99%, p ≤ 0.001) and ST395 (94%, p < 0.012). Being in ICU (OR: 7.9; CI: 1.43–55.98; p = 0.024), kfu (OR:27.0; CI: 5.67–179.65; p < 0.001) and ST101 (OR: 17.2; CI: 2.45–350.40; p = 0.01) were found to be predictors of 30-day mortality. Even the neutrophil uptake of kfu+-ybtS+ ColR-Kp was significantly higher than kfu--ybtS- ColR-Kp (phagocytosis rate: 78% vs. 65%, p < 0.001), and the kfu+-ybtS+ ColR-Kp survived more than kfu--ybtS- ColR-Kp (median survival index: 7.90 vs. 4.22; p = 0.001). The kfu+-ybtS+ ColR-Kp stimulated excessive NET formation. Iron uptake systems in high-risk clones of colistin-resistant K. pneumoniae enhance the success of survival against the neutrophil phagocytic defense and stimulate excessive NET formation. The drugs targeted to iron uptake systems would be a promising approach for the treatment of colistin-resistant high-risk clones of K. pneumoniae infections. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
Emergence of Colistin and Carbapenem Resistance in Extended-Spectrum β-Lactamase Producing Klebsiella pneumoniae Isolated from Chickens and Humans in Egypt
Biology 2021, 10(5), 373; https://doi.org/10.3390/biology10050373 - 26 Apr 2021
Cited by 16 | Viewed by 2137
Abstract
This study investigated the frequency of carbapenem and colistin resistance in ESBL-producing K. pneumoniae (ESBLK) isolates recovered from chickens and their environment, contact farm workers and hospitalized patients in Egypt. Further, the phenotypic and genotypic relationships between the community and hospital-acquired K. pneumoniae [...] Read more.
This study investigated the frequency of carbapenem and colistin resistance in ESBL-producing K. pneumoniae (ESBLK) isolates recovered from chickens and their environment, contact farm workers and hospitalized patients in Egypt. Further, the phenotypic and genotypic relationships between the community and hospital-acquired K. pneumoniae isolates in the same geographical area were investigated. From 272 total samples, 37 (13.6%) K. pneumoniae isolates were identified, of which 20 (54.1%) were hypervirulent. All isolates (100%) were multidrug-resistant (MDR) with multiple antibiotic resistance (MAR) indices ranging from 0.19 to 0.94. Colistin-resistant isolates (18.9%) displayed colistin MIC values >2 μg/mL, all harbored the mcr-1 gene. All isolates from patients (13/90, 14.4%), workers (5/22, 22.7%), chickens (9/100, 9%) and the environment (10/60, 16.7%) harbored a single or multiple β-lactamase genes, blaSHV, blaTEM, blaCTX-M1 and blaOXA-1, often in combination with carbapenemase genes (blaVIM, blaNDM-1 or blaIMP; 45.9%), the mcr-1 gene (18.9%) or both (13.5%). Enterobacterial repetitive intergenic consensus (ERIC)–PCR genotyping revealed 24 distinct ERIC types (ETs) with a discrimination index of 0.961. Six ETs showed clusters of identical isolates from chicken and human sources. The increased frequency and genetic relatedness of ESBLK and carbapenemase-producing K. pneumoniae (CPK) from chickens and humans pose a public health threat that urge more prudent use of antimicrobials in chicken farms to avoid the propagation and expansion of both ESBLK and CPK from the chicken sources to humans. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Article
MLST-Based Analysis and Antimicrobial Resistance of Staphylococcus epidermidis from Cases of Sheep Mastitis in Greece
Biology 2021, 10(3), 170; https://doi.org/10.3390/biology10030170 - 24 Feb 2021
Cited by 6 | Viewed by 2040
Abstract
Staphylococcus epidermidis is an important causal agent of ovine mastitis. A literature search indicated a lack of systematic studies of causal agents of the infection by using multi-locus sequence typing (MLST). The objectives were to analyse MLST-based data and evaluate the antimicrobial resistance [...] Read more.
Staphylococcus epidermidis is an important causal agent of ovine mastitis. A literature search indicated a lack of systematic studies of causal agents of the infection by using multi-locus sequence typing (MLST). The objectives were to analyse MLST-based data and evaluate the antimicrobial resistance of S. epidermidis isolates from ovine mastitis in Greece. The database included 1593 isolates from 46 countries: 1215 of human, 195 of environmental and 134 of animal origin, distributed into 949 sequence types (STs) and cumulatively with 450 alleles therein. Among mastitis isolates, bovine isolates were distributed into 36 different STs and ovine ones into 15 STs. The 33 isolates from ovine mastitis in Greece were in 15 different STs, 6 of these (ST677, ST678, ST700, ST 709, ST710, ST711) assigned for the first time; in addition, 5 alleles (65 for arcC, 59 for aroE, 56 and 57 for gtr and 48 for tpiA) were identified for the first time. The spanning tree of these isolates included 15 nodes and 14 edges (i.e., branches). Among these isolates, 19 showed resistance to antimicrobial agents (tetracycline, penicillin, fucidic adic, erythromycin, clindamycin, cefoxitin). Resistance-related genes (tetK, tetT, msrA, tetM, tetS, ermC, mecA) were detected. There was no association between STs and resistance to antimicrobial agents. Isolates with antimicrobial resistance were recovered more often from flocks where hand-milking was practised. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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Jump to: Research

Systematic Review
Emerging Status of Multidrug-Resistant Bacteria and Fungi in the Arabian Peninsula
Biology 2021, 10(11), 1144; https://doi.org/10.3390/biology10111144 - 06 Nov 2021
Cited by 5 | Viewed by 2280
Abstract
We aimed to identify the prevalence and emerging status of multidrug-resistant bacteria and fungi and their associated mortality in nine countries in the Arabian Peninsula. Original research articles and case studies regarding multidrug-resistant bacteria and fungi in the Arabian Peninsula, published during the [...] Read more.
We aimed to identify the prevalence and emerging status of multidrug-resistant bacteria and fungi and their associated mortality in nine countries in the Arabian Peninsula. Original research articles and case studies regarding multidrug-resistant bacteria and fungi in the Arabian Peninsula, published during the last 10 years, were retrieved from PubMed and Scopus. A total of 382 studies were included as per the inclusion and exclusion criteria, as well as the PRISMA guidelines, from a thorough screening of 1705 articles, in order to analyse the emerging status and mortality. The emerging nature of >120 multidrug-resistant (MDR) bacteria and fungi in the Arabian Peninsula is a serious concern that requires continuous monitoring and immediate preventive measures. More than 50% (n = 453) of multidrug-resistant, microbe-associated mortality (n = 871) in the Arabian Peninsula was due to MDR Acinetobacter baumannii, Mycobacterium tuberculosis and Staphylococcus aureus infection. Overall, a 16.51% mortality was reported among MDR-infected patients in the Arabian Peninsula from the 382 articles of this registered systematic review. MDR A. baumannii (5600 isolates) prevailed in all the nine countries of the Arabian Peninsula and was one of the fastest emerging MDR bacteria with the highest mortality (n = 210). A total of 13,087 Mycobacterium tuberculosis isolates were reported in the region. Candida auris (580 strains) is the most prevalent among the MDR fungal pathogen in the Arabian Peninsula, having caused 54 mortalities. Active surveillance, constant monitoring, the development of a candidate vaccine, an early diagnosis of MDR infection, the elimination of multidrug resistance modulators and uninterrupted preventive measures with enhanced data sharing are mandatory to control MDR infection and associated diseases of the Arabian Peninsula. Accurate and rapid detection methods are needed to differentiate MDR strain from other strains of the species. This review summarises the logical relation, prevalence, emerging status and associated mortality of MDR microbes in the Arabian Peninsula. Full article
(This article belongs to the Special Issue Microbial Diversity and Microbial Resistance)
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