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Interactions between Gender and Sepsis—Implications for the Future
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SARS-CoV-2 Related Antibody-Dependent Enhancement Phenomena In Vitro and In Vivo
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Acetylcholine Esterase Inhibitory Effect, Antimicrobial, Antioxidant, Metabolomic Profiling, and an In Silico Study of Non-Polar Extract of The Halotolerant Marine Fungus Penicillium chrysogenum MZ945518
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Should We Expect an Increase in the Number of Cancer Cases in People with Long COVID?
Journal Description
Microorganisms
Microorganisms
is a scientific, peer-reviewed, open access journal of microbiology, published monthly online by MDPI. The Hellenic Society Mikrobiokosmos (MBK), the Spanish Society for Nitrogen Fixation (SEFIN) and the Society for Microbial Ecology and Disease (SOMED) are affiliated with the Microorganisms, and their members receive a discount on the article processing charges.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), PubMed, PMC, PubAg, CAPlus / SciFinder, AGRIS, and other databases.
- Journal Rank: JCR - Q2 (Microbiology)
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 14.1 days after submission; acceptance to publication is undertaken in 2.9 days (median values for papers published in this journal in the second half of 2022).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
- Testimonials: See what our editors and authors say about the Microorganisms.
- Companion journal: Applied Microbiology.
Impact Factor:
4.926 (2021);
5-Year Impact Factor:
5.143 (2021)
Latest Articles
Biocontrol and Probiotic Function of Non-Saccharomyces Yeasts: New Insights in Agri-Food Industry
Microorganisms 2023, 11(6), 1450; https://doi.org/10.3390/microorganisms11061450 (registering DOI) - 30 May 2023
Abstract
Fermented food matrices, including beverages, can be defined as the result of the activity of complex microbial ecosystems where different microorganisms interact according to different biotic and abiotic factors. Certainly, in industrial production, the technological processes aim to control the fermentation to place
[...] Read more.
Fermented food matrices, including beverages, can be defined as the result of the activity of complex microbial ecosystems where different microorganisms interact according to different biotic and abiotic factors. Certainly, in industrial production, the technological processes aim to control the fermentation to place safe foods on the market. Therefore, if food safety is the essential prerogative, consumers are increasingly oriented towards a healthy and conscious diet driving the production and consequently the applied research towards natural processes. In this regard, the aim to guarantee the safety, quality and diversity of products should be reached limiting or avoiding the addition of antimicrobials or synthetic additives using the biological approach. In this paper, the recent re-evaluation of non-Saccharomyces yeasts (NSYs) has been reviewed in terms of bio-protectant and biocontrol activity with a particular focus on their antimicrobial power using different application modalities including biopackaging, probiotic features and promoting functional aspects. In this review, the authors underline the contribution of NSYs in the food production chain and their role in the technological and fermentative features for their practical and useful use as a biocontrol agent in food preparations.
Full article
(This article belongs to the Special Issue Latest Review Papers on Antimicrobial Agents and Resistance 2023)
Open AccessReview
Influence of the Probiotic L. reuteri on Periodontal Clinical Parameters after Nonsurgical Treatment: A Systematic Review
by
, , , , and
Microorganisms 2023, 11(6), 1449; https://doi.org/10.3390/microorganisms11061449 (registering DOI) - 30 May 2023
Abstract
The aim of this systematic review was to evaluate the actual efficacy of Lactobacillus reuteri (L. reuteri) on the periodontal clinical parameters when used concomitantly to the nonsurgical periodontal treatment. Searches were conducted through PubMed Central, Online Knowledge Library, Science Direct,
[...] Read more.
The aim of this systematic review was to evaluate the actual efficacy of Lactobacillus reuteri (L. reuteri) on the periodontal clinical parameters when used concomitantly to the nonsurgical periodontal treatment. Searches were conducted through PubMed Central, Online Knowledge Library, Science Direct, Scielo, and Cochrane databases from 2012 to 2022. The focused question was “In patients with periodontitis, will the probiotic L. reuteri, when administrated as an adjunct to nonsurgical periodontal treatment, compared to the nonsurgical periodontal treatment alone, result in better clinical outcomes?” The following information was extracted from the articles: author and year of publication, type of study, follow-up, sample size and number of defects, and clinical characteristics and details. All included studies were qualitatively assessed using the Critical Appraisal tools according to the Joanna Briggs Institute. Twenty-four articles were full-text reading, but only 9 articles were included. The number of patients enrolled was 287, aged between 18 and 56 years. All periodontal parameters were evaluated. The “follow-up” varied (14, 40, 84, 90, 180, and 360 days). Most articles supported the clinical benefits of L. reuteri as an adjunct to SRP compared to SRP alone. A common finding at the beginning period was thatno statistically different results were observed between the test and control groups; otherwise, at the last period, a significant improvement was found in favor of the probiotic use (p = 0.001) for all the clinical parameters. The use of L. reuteri as an adjunct to nonsurgical periodontal treatment may result in significantly better clinical outcomes than nonsurgical periodontal treatment alone; but the conclusion must be carefully interpreted because of the heterogeneity found among the studies.
Full article
(This article belongs to the Special Issue Biomarkers in Oral Health and Diseases: New Advances and Treatment Strategies)
Open AccessArticle
A Microbiological Approach to Alleviate Soil Replant Syndrome in Peaches
Microorganisms 2023, 11(6), 1448; https://doi.org/10.3390/microorganisms11061448 (registering DOI) - 30 May 2023
Abstract
Replant syndrome (RS) is a global problem characterized by reduced growth, production life, and yields of tree fruit/nut orchards. RS etiology is unclear, but repeated monoculture plantings are thought to develop a pathogenic soil microbiome. This study aimed to evaluate a biological approach
[...] Read more.
Replant syndrome (RS) is a global problem characterized by reduced growth, production life, and yields of tree fruit/nut orchards. RS etiology is unclear, but repeated monoculture plantings are thought to develop a pathogenic soil microbiome. This study aimed to evaluate a biological approach that could reduce RS in peach (Prunus persica) orchards by developing a healthy soil bacteriome. Soil disinfection via autoclave followed by cover cropping and cover crop incorporation was found to distinctly alter the peach soil bacteriome but did not affect the RS etiology of RS-susceptible ‘Lovell’ peach seedlings. In contrast, non-autoclaved soil followed by cover cropping and incorporation altered the soil bacteriome to a lesser degree than autoclaving but induced significant peach growth. Non-autoclaved and autoclaved soil bacteriomes were compared to highlight bacterial taxa promoted by soil disinfection prior to growing peaches. Differential abundance shows a loss of potentially beneficial bacteria due to soil disinfection. The treatment with the highest peach biomass was non-autoclaved soil with a cover crop history of alfalfa, corn, and tomato. Beneficial bacterial species that were cultivated exclusively in the peach rhizosphere of non-autoclaved soils with a cover crop history were Paenibacillus castaneae and Bellilinea caldifistulae. In summary, the non-autoclaved soils show continuous enhancement of beneficial bacteria at each cropping phase, culminating in an enriched rhizosphere which may help alleviate RS in peaches.
Full article
(This article belongs to the Special Issue Plant Root Interaction with Associated Microbiomes)
Open AccessArticle
The Impact of Anti-Inflammatory Drugs on the Prokaryotic Community Composition and Selected Bacterial Strains Based on Microcosm Experiments
Microorganisms 2023, 11(6), 1447; https://doi.org/10.3390/microorganisms11061447 (registering DOI) - 30 May 2023
Abstract
Non-steroidal anti-inflammatory drugs (NSAIDs) are increasingly recognized as potential environmental contaminants that may induce toxicity in aquatic ecosystems. This 3-week microcosm experiment explores the acute impacts of NSAIDs, including diclofenac (DCF), ibuprofen (IBU), and acetylsalicylic acid (ASA), on bacterial communities using a wide
[...] Read more.
Non-steroidal anti-inflammatory drugs (NSAIDs) are increasingly recognized as potential environmental contaminants that may induce toxicity in aquatic ecosystems. This 3-week microcosm experiment explores the acute impacts of NSAIDs, including diclofenac (DCF), ibuprofen (IBU), and acetylsalicylic acid (ASA), on bacterial communities using a wide range of these substances (200–6000 ppm). The results showed that the NSAID-treated microcosms had higher cell count values than control samples, though the diversity of microbial communities decreased. The isolated heterotrophic bacteria mostly belonged to Proteobacteria, particularly Klebsiella. Next-generation sequencing (NGS) revealed that NSAIDs altered the structure of the bacterial community composition, with the proportion of Proteobacteria aligning with the selective cultivation results. Bacteria had higher resistance to IBU/ASA than to DCF. In DCF-treated microcosms, there has been a high reduction of the number of Bacteroidetes, whereas in the microcosms treated with IBU/ASA, they have remained abundant. The numbers of Patescibacteria and Actinobacteria have decreased across all NSAID-treated microcosms. Verrucomicrobia and Planctomycetes have tolerated all NSAIDs, even DCF. Cyanobacteria have also demonstrated tolerance to IBU/ASA treatment in the microcosms. The archaeal community structure was also impacted by the NSAID treatments, with Thaumarchaeota abundant in all microcosms, especially DCF-treated microcosms, while Nanoarchaeota is more typical of IBU/ASA-treated microcosms with lower NSAID concentrations. These results indicate that the presence of NSAIDs in aquatic environments could lead to changes in the composition of microbial communities.
Full article
(This article belongs to the Special Issue Microbial Communities and Antimicrobial Resistance in Contaminated Aquatic and Terrestrial Environments)
Open AccessArticle
Genome Analysis of Methicillin-Resistant and Methicillin-Susceptible Staphylococcus aureus ST398 Strains Isolated from Patients with Invasive Infection
by
, , , , and
Microorganisms 2023, 11(6), 1446; https://doi.org/10.3390/microorganisms11061446 (registering DOI) - 30 May 2023
Abstract
Background: Using genomic data, we determined the origin of MRSA ST398 isolates responsible for invasive infection in patients with no known livestock contact. Methods: We sequenced the genome of seven MSSA and four MRSA ST398 isolates from patients with invasive infections between 2013
[...] Read more.
Background: Using genomic data, we determined the origin of MRSA ST398 isolates responsible for invasive infection in patients with no known livestock contact. Methods: We sequenced the genome of seven MSSA and four MRSA ST398 isolates from patients with invasive infections between 2013 and 2017, using the Illumina technique. Prophage-associated virulence genes and resistance genes were identified. To determine the origin of the isolates, their genome sequences were included in phylogenetic analysis also encompassing the ST398 genomes available on NCBI. Results: All isolates carried the φSa3 prophage, but with variations in the immune evasion cluster: type C in MRSA isolates, and type B in MSSA isolates. All MSSA belonged to the spa type t1451. MRSA strains had the same SCCmec type IVa (2B) cassette and belonged to spa types t899, t4132, t1939 and t2922. All MRSA harbored the tetracycline resistance gene, tet(M). Phylogenetic analysis revealed that MSSA isolates belonged to a cluster of human-associated isolates, while MRSA isolates belonged to a cluster containing livestock-associated MRSA. Conclusion: We showed that the clinical isolates MRSA and MSSA ST398 have different origins. An acquisition of virulence genes by livestock-associated MRSA isolates allows them to induce an invasive infection in human.
Full article
(This article belongs to the Special Issue Emerging and Re-emerging Infectious Diseases: Recent Developments on Therapeutics, Clinical Epidemiology and Transmission)
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Open AccessArticle
Complete Biodegradation of Diclofenac by New Bacterial Strains: Postulated Pathways and Degrading Enzymes
Microorganisms 2023, 11(6), 1445; https://doi.org/10.3390/microorganisms11061445 (registering DOI) - 30 May 2023
Abstract
The accumulation of xenobiotic compounds in different environments interrupts the natural ecosystem and induces high toxicity in non-target organisms. Diclofenac is one of the commonly used pharmaceutical drugs that persist in the environment due to its low natural degradation rate and high toxicity.
[...] Read more.
The accumulation of xenobiotic compounds in different environments interrupts the natural ecosystem and induces high toxicity in non-target organisms. Diclofenac is one of the commonly used pharmaceutical drugs that persist in the environment due to its low natural degradation rate and high toxicity. Therefore, this study aimed to isolate potential diclofenac-degrading bacteria, detect the intermediate metabolites formed, and determine the enzyme involved in the degradation process. Four bacterial isolates were selected based on their ability to utilize a high concentration of diclofenac (40 mg/L) as the sole carbon source. The growth conditions for diclofenac degradation were optimized, and bacteria were identified as Pseudomonas aeruginosa (S1), Alcaligenes aquatilis (S2), Achromobacter spanius (S11), and Achromobacter piechaudii (S18). The highest percentage of degradation was recorded (97.79 ± 0.84) after six days of incubation for A. spanius S11, as analyzed by HPLC. To detect and identify biodegradation metabolites, the GC-MS technique was conducted for the most efficient bacterial strains. In all tested isolates, the initial hydroxylation of diclofenac was detected. The cleavage step of the NH bridge between the aromatic rings and the subsequent cleavage of the ring adjacent to or in between the two hydroxyl groups of polyhydroxylated derivatives might be a key step that enables the complete biodegradation of diclofenac by A. piechaudii S18, as well as P. aeruginosa S1. Additionally, the laccase, peroxidase, and dioxygenase enzyme activities of the two Achromobacter strains, as well as P. aeruginosa S1, were tested in the presence and absence of diclofenac. The obtained results from this work are expected to be a useful reference for the development of effective detoxification bioprocesses utilizing bacterial cells as biocatalysts. The complete removal of pharmaceuticals from polluted water will stimulate water reuse, meeting the growing worldwide demand for clean and safe freshwater.
Full article
(This article belongs to the Section Environmental Microbiology)
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Open AccessArticle
Effects of Different Yeast Selenium Levels on Rumen Fermentation Parameters, Digestive Enzyme Activity and Gastrointestinal Microflora of Sika Deer during Antler Growth
Microorganisms 2023, 11(6), 1444; https://doi.org/10.3390/microorganisms11061444 (registering DOI) - 30 May 2023
Abstract
The aim of this experiment was to study the effects of different selenium supplemental levels on rumen fermentation microflora of sika deer at the velvet antler growth stage. A total of 20 5-year-old, healthy sika deer at the velvet antler growth stage with
[...] Read more.
The aim of this experiment was to study the effects of different selenium supplemental levels on rumen fermentation microflora of sika deer at the velvet antler growth stage. A total of 20 5-year-old, healthy sika deer at the velvet antler growth stage with an average body weight of (98.08 ± 4.93) kg were randomly divided into 4 groups, and each group was fed in a single house. The SY1 group was the control group, and the SY2 group, SY3 group and SY4 group were fed a basal diet supplemented with 0.3, 1.2 and 4.8 mg/kg selenium, respectively. The pretest lasted for 7 days, and the formal trial period lasted for 110 days. The results show that: At the velvet antler growth stage, the digestibility of neutral detergent fiber and acid detergent fiber of sika deer in the SY2 group was significantly higher than that in the control group (p < 0.01). The digestibility of cellulose and crude fiber of sika deer in the SY2 group was significantly higher than those in the SY3 and SY4 groups (p < 0.01) and significantly higher than that in the control group (p < 0.05). The contents of acetic acid and propionic acid in the rumen fluid of sika deer in the SY2 group were significantly higher than those in the SY1 group (p < 0.05). Digestive enzyme analysis of rumen fluid at the velvet antler growth stage showed that the activity of protease in rumen fluid in the SY2 group was significantly lower than those in the SY1 group and SY4 group (p < 0.05). The relative abundance of Fibrobacter succinogenes in the SY2 group was significantly higher than that in the SY1 group (p < 0.05) and extremely significantly higher than those in the SY3 and SY4 groups (p < 0.01). Correlation analysis between yeast selenium level and bacterial abundance showed that the yeast selenium content in rumen fluid was significantly positively correlated with Butyrivibrio and Succiniclasticum (p < 0.01). Further verification of bacterial flora functioning showed that the SY2 group was more inclined to the degradation and utilization of fiber. In conclusion, 0.3 mg/kg selenium supplementation can increase the abundance of Prevotella ruminicola and Fibrobacter succinogenes in the rumen of sika deer and improve the degradation of fibrous substances by mediating the catabolite repression process.
Full article
(This article belongs to the Special Issue Gastrointestinal Fermentation and Microbiota)
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Open AccessReview
The Impact of the Female Genital Microbiota on the Outcome of Assisted Reproduction Treatments
by
, , , , , , , , , , and
Microorganisms 2023, 11(6), 1443; https://doi.org/10.3390/microorganisms11061443 (registering DOI) - 30 May 2023
Abstract
The vaginal microbiota plays a critical role in the health of the female genital tract, and its composition contributes to gynecological disorders and infertility. Lactobacilli are the dominant species in the female genital tract: their production of lactic acid, hydrogen peroxide, and bacteriocins
[...] Read more.
The vaginal microbiota plays a critical role in the health of the female genital tract, and its composition contributes to gynecological disorders and infertility. Lactobacilli are the dominant species in the female genital tract: their production of lactic acid, hydrogen peroxide, and bacteriocins prevents the invasion and growth of pathogenic microorganisms. Several factors such as hormonal changes, age of reproduction, sexual practices, menstrual cycle, pregnancy, and antimicrobial drugs use can cause imbalance and dysbiosis of the vaginal microbiota. This review aims to highlight the impact of the vaginal microbiota in Assisted Reproductive Technology techniques (ART) and it examines the factors that influence the vaginal microbiota, the consequences of dysbiosis, and potential interventions to restore a healthy female genital tract.
Full article
(This article belongs to the Special Issue Vaginal Microbiota: Impact on Health and Disease)
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Open AccessArticle
Oral Myco- and Bacteriobiota and Yeast Infections in Mechanically Ventilated COVID-19 Patients
by
, , , , , , and
Microorganisms 2023, 11(6), 1442; https://doi.org/10.3390/microorganisms11061442 (registering DOI) - 30 May 2023
Abstract
Critically ill COVID-19 patients requiring mechanical ventilation in the intensive care unit are at risk of developing invasive candidiasis. In this study we aimed to (1) characterize oral cultivable mycobiota of mechanically ventilated adult COVID-19 patients in an ICU setting by sampling four
[...] Read more.
Critically ill COVID-19 patients requiring mechanical ventilation in the intensive care unit are at risk of developing invasive candidiasis. In this study we aimed to (1) characterize oral cultivable mycobiota of mechanically ventilated adult COVID-19 patients in an ICU setting by sampling four distinct oral niches in two fixed time points with regards to oral health status, (2) investigate Candida spp. infections in this population, and (3) compare oral mycobiota with selected bacteriobiota strains during the observation in the ICU. We recruited 56 adult COVID-19 patients who qualified for mechanical ventilation. Patients received either standard or extended oral care procedures with tooth brushing. Oral samples were taken first within 36 h and after 7 days of intubation. Yeast-like fungi were identified by MALDI/TOF mass spectrometry. Yeast infection cases were retrospectively analyzed. Candida spp. in oral sampling was identified in 80.4% and 75.7%, C. albicans in 57.1% and 61.1%, and non-albicans Candida species in 48.2% and 47.2% patients at baseline and follow-up, respectively. There were no differences in the overall CFU counts of Candida spp. species and individual Candida species in oral samples, both at baseline and follow-up. At baseline, a higher prevalence of Candida spp. was associated with a higher identification rate of Lactobacillus spp. (64.4% vs. 27.3%, p = 0.041). At follow-up, there was a borderline lower prevalence of Candida spp. in patients with Lactobacillus spp. identified (57.1% vs. 87.0%, p = 0.057). The incidence rate of candidiasis was 5.4% and the incidence density was 3.1/1000 pds. In conclusion, non-albicans Candida species in oral samples were identified in nearly half of patients. Oral health was moderately impaired. A high incidence of yeast infections, including invasive cases, in patients hospitalized in the ICU due to COVID-19 and requiring mechanical ventilation was noted. Severe COVID-19 and disease-specific interventions within the ICU possibly played a major role promoting Candida spp. infections.
Full article
(This article belongs to the Special Issue Infectious Diseases, New Approaches to Old Problems 2.0)
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Open AccessArticle
Association of Toxoplasmosis and COVID-19 in a Mexican
Population
by
, , , , and
Microorganisms 2023, 11(6), 1441; https://doi.org/10.3390/microorganisms11061441 (registering DOI) - 30 May 2023
Abstract
SARS-CoV-2 is the causal agent of COVID-19; the first report of SARS-CoV-2 infection was in December 2019 in Wuhan, China. This virus has since caused the largest pandemic in history, and the number of deaths and infections has been significant. Nevertheless, the development
[...] Read more.
SARS-CoV-2 is the causal agent of COVID-19; the first report of SARS-CoV-2 infection was in December 2019 in Wuhan, China. This virus has since caused the largest pandemic in history, and the number of deaths and infections has been significant. Nevertheless, the development of vaccines has helped to reduce both deaths and infections. Comorbidities such as diabetes, hypertension, heart and lung diseases, and obesity have been identified as additional risk factors for infection and the progression of COVID-19. Additionally, latent toxoplasmosis has been reported to be a risk factor for acquiring COVID-19 in some studies, but other studies have suggested a negative association between these two infections. Furthermore, in patients after vaccination or with COVID-19 and coinfection, an increase in the lethality and mortality of toxoplasmosis has been observed. Therefore, the objective of the current study is to determine the association of toxoplasmosis with COVID-19 in patients diagnosed with COVID-19. Serum samples from 384 patients previously diagnosed with COVID-19 using IgG antibodies against the S1/S2 antigens of SARS-CoV-2 were collected. Subsequently, anti-Toxoplasma IgG and IgM antibodies were analyzed with ELISA. Statistical analysis was performed using SPSS Version 20.0 frequencies, percentages, 2 × 2 tables, and the Pearson correlation coefficient. IgG and IgM anti-Toxoplasma antibodies were positive in 105/384 (27.34%) and (26/191) 13.6% of patients, respectively. The positivity for both infections was higher in patients aged >40 years old. Subjects who were overweight or obese were mainly positive for both IgG antibodies against S1/S2 SARS-CoV-2 and Toxoplasma antibodies. In conclusion, the coinfection rate was 21.7%. The prevalence of S1/S2 SARS-CoV-2 was 308/384 (80.2%), and the percentage of Toxoplasma antibodies was 27.34%.
Full article
(This article belongs to the Special Issue Advances in SARS-CoV-2 Infection 2.0)
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Bacterial Communities Associated with Houseflies (Musca domestica L.) Inhabiting Hospices in South Africa
by
, , , , and
Microorganisms 2023, 11(6), 1440; https://doi.org/10.3390/microorganisms11061440 - 30 May 2023
Abstract
Houseflies are alleged reservoirs as well as vectors of human and animal pathogens, including bacteria, because they frequently have contact with animal excreta and decaying organic substances. The rapid adaptation process of ingested microbes in the insect gut may involve gene transfer, including
[...] Read more.
Houseflies are alleged reservoirs as well as vectors of human and animal pathogens, including bacteria, because they frequently have contact with animal excreta and decaying organic substances. The rapid adaptation process of ingested microbes in the insect gut may involve gene transfer, including antibiotic resistance determinants among different bacterial strains. Six hundred and fifty-seven (n = 657) houseflies were collected from hospices and were identified morphologically and genetically using the 16S rRNA, CO1, and ITS2 barcoding genes. This study also characterized the bacterial communities harboured by the captured houseflies using 16S rRNA metabarcoding on the next-generation sequencing (NGS) platform and further sought to detect antibiotic resistance traits by using gene-specific PCR assays. Generated sequences for the targeted gene fragments matched with Musca domestica and all the sequences were deposited to the GenBank database. The 16S rRNA metabarcoding analysis revealed that the most abundant phyla detected with variable abundance observed among all the houseflies were Proteobacteria, followed by Firmicutes, and Bacteroidetes. Furthermore, the NGS data revealed the presence of multiple bacterial genera, including Providencia, Enterobacter, Dysgonomonas, Escherichia-Shigella, Klebsiella, Pseudomonas, and Streptococcus, which are known to harbour potentially pathogenic species of animals and humans. Antibiotic resistance genes detected from the housefly DNA in this study included ermB, tetA, blaSHV, and blaTEM. Moreover, these genes are associated with resistance to erythromycin, tetracycline, and beta-lactams antibiotics, respectively. The presence of bacterial pathogens and the detection of antibiotic resistance genes from the houseflies collected from the hospices indicates the possible health risk to patients in hospices and the surrounding community. Therefore, it is imperative to keep high standards of hygiene, food preparation, safety, and control of houseflies in hospices.
Full article
(This article belongs to the Special Issue Pathogen Transmission among Animals and Humans: A One Health Approach)
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Copper-Contaminated Substrate Biosorption by Penicillium sp. Isolated from Kefir Grains
by
, , , , , , , , , and
Microorganisms 2023, 11(6), 1439; https://doi.org/10.3390/microorganisms11061439 - 30 May 2023
Abstract
In this bioremediation study, the fungus Penicillium sp. isolated from kefir grains was evaluated for its resistance to copper in the culture medium. Penicillium sp. was cultivated in liquid medium prepared using 2% malt-agar at pH 7.0. Biomass of the fungus was significantly
[...] Read more.
In this bioremediation study, the fungus Penicillium sp. isolated from kefir grains was evaluated for its resistance to copper in the culture medium. Penicillium sp. was cultivated in liquid medium prepared using 2% malt-agar at pH 7.0. Biomass of the fungus was significantly reduced, but only when 800 mg·L−1 of Cu(NO3)2 copper nitrate was used. The effect on radial growth of the fungus in experiments combining different pH values and the inorganic contaminant showed an inhibition of 73% at pH 4.0, 75% at pH 7.0 and 77% at pH 9.0 in liquid medium. Thus, even though the growth of Penicillium sp. could be inhibited with relatively high doses of copper nitrate, images obtained with scanning electron microscopy showed the preservation of fungal cell integrity. Therefore, it can be concluded that Penicillium sp. isolated from kefir grains can survive while performing bioremediation to minimize the negative effects of copper on the environment through biosorption.
Full article
(This article belongs to the Special Issue Strategies for Biodegradation of Micropollutants)
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Analysis of Etiology of Community-Acquired and Nosocomial Urinary Tract Infections and Antibiotic Resistance of Isolated Strains: Results of a 3-Year Surveillance (2020–2022) at the Pediatric Teaching Hospital in Warsaw
by
, , , and
Microorganisms 2023, 11(6), 1438; https://doi.org/10.3390/microorganisms11061438 - 29 May 2023
Abstract
Urinary tract infections (UTIs) remain the most common infections diagnosed in outpatients and hospitalized patients. This study was designed to determine the patterns of antibiotic resistance and the prevalence of uropathogens causing UTIs in pediatric patients hospitalized between 1 January 2020 and 31
[...] Read more.
Urinary tract infections (UTIs) remain the most common infections diagnosed in outpatients and hospitalized patients. This study was designed to determine the patterns of antibiotic resistance and the prevalence of uropathogens causing UTIs in pediatric patients hospitalized between 1 January 2020 and 31 December 2022 at Teaching Hospital in Warsaw. The most frequent species isolated from urine samples were E. coli (64.5%), Klebsiella spp. (11.6%), and Enterococcus spp. (6.1%). UTIs caused by Enterobacter spp., Enterococcus spp., and Klebsiella spp. were significantly more common in children younger than three months of age than in children older than three months (p < 0.001). Trimethoprim and trimethoprim–sulfamethoxazole were the least active compounds against Enterobacterales with the resistance of E. coli, Klebsiella spp., P. mirabilis, and Enterobacter spp. in the range of 26.7/25.2%, 48.4/40.4%, 51.1/40.4%, and 15.8/13.2% respectively. Ampicillin was also found to have resistance rates for E. coli of 54.9% and P. mirabilis of 44.7%. Cefalexin and cefuroxime were highly active towards Enterobacterales except for Klebsiella spp., in which the resistance level reached 40%. Regarding third- and fourth- generation cephalosporins, resistance in E. coli and P. mirabilis was observed in approximately 2–10% of the isolates, but in Klebsiella spp. and Enterobacter spp. ranged over 30%. The resistance of Enterobacterales to carbapenems, nitrofurantoin, and fosfomycin was below 1%. The quinolones resistance was very high for Klebsiella spp. (31.1%) and P. mirabilis (29.8%) and three times lower for E. coli (11.9%), P. aeruginosa (9.3%), Enterobacter spp. (2.6%), and E. faecalis (4.6%). Resistance to multiple antibiotic classes was identified in 396 Enterobacterales strains, 394 of which were multi-drug resistant (MDR) and 2 were extensive drug-resistant (XDR). In the case of E. coli, 30% of isolates were MDR, with the proportion of strains having this exact resistance pattern similar in all of the analyzed years; no E. coli XDR strains were isolated. The number of Klebsiella spp. MDR strains was much higher in 2022 (60%) than in 2021 (47.5%). In the analyzed time, only one strain of K. pneumonia XDR, producing New Delhi metallo-β-lactamase, was isolated. Monitoring infection trends is essential to improve control and limit the rise of bacterial resistance.
Full article
(This article belongs to the Special Issue Urinary Tract Infections and Antibiotic Resistance)
Open AccessArticle
Mandatory Notification of Panton–Valentine Leukocidin-Positive Methicillin-Resistant Staphylococcus aureus in Saxony, Germany: Analysis of Cases from the City of Leipzig in 2019
Microorganisms 2023, 11(6), 1437; https://doi.org/10.3390/microorganisms11061437 - 29 May 2023
Abstract
In Germany, Saxony is the only federal state where the detection of a Panton–Valentine Leukocidin (PVL)-positive Methicillin-resistant Staphylococcus aureus (MRSA) has to be notified to the local health authority (LHA). The LHA reports the case to the state health authority and introduces concrete
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In Germany, Saxony is the only federal state where the detection of a Panton–Valentine Leukocidin (PVL)-positive Methicillin-resistant Staphylococcus aureus (MRSA) has to be notified to the local health authority (LHA). The LHA reports the case to the state health authority and introduces concrete infection control measures. We analyzed isolates from the respective cases in 2019, which were collected in local microbiological laboratories and sent to the National Reference Centre (NRC) for Staphylococci and Enterococci for strain characterization and typing. Antibiotic resistance testing was done by broth microdilution. Molecular characterization was performed using spa and SCCmec typing, MLST, and the PCR detection of marker genes associated with distinct MRSA lineages. Demographic and clinical data of the individual cases were assessed and the LHA performed epidemiological investigations. Thirty-nine (index) persons, diagnosed with a PVL-positive MRSA, were initially reported to the LHA. Most patients suffered from skin and soft-tissue infections (SSTI). For 21 of the index cases, household contacts were screened for MRSA. Seventeen out of 62 contacts were also colonized with a PVL-positive MRSA. The median age of altogether 58 individuals was 23.5 years. In over half of the cases, the home country was not Germany and/or a history of travel or migration was reported. Molecular characterization revealed the presence of various epidemic community-associated MRSA lineages, with “USA300”, including the North American Epidemic (ST8-MRSA-IVa) and the South American Epidemic Clone (ST8-MRSA-IVc), the “Sri Lankan Clone” (ST5-MRSA-IVc), and the “Bengal Bay Clone” (ST772-MRSA-V) being more prevalent. In eight out of nine households, the contact persons were colonized with the same clone as the respective index case, suggesting a close epidemic and microbiological link. The obligation to report PVL-positive MRSA enables us to detect the occurrence of PVL-producing MRSA and its spread in the population as early as possible. Timely detection allows the targeted deployment of reliable anti-infective measures.
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(This article belongs to the Special Issue Characterisation and Molecular Analysis of Staphylococcal Species: Their Impact on Colonization and Infection)
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Open AccessReview
Cold Sulfur Springs—Neglected Niche for Autotrophic Sulfur-Oxidizing Bacteria
Microorganisms 2023, 11(6), 1436; https://doi.org/10.3390/microorganisms11061436 - 29 May 2023
Abstract
Since the beginning of unicellular life, dissimilation reactions of autotrophic sulfur bacteria have been a crucial part of the biogeochemical sulfur cycle on Earth. A wide range of sulfur oxidation states is reflected in the diversity of metabolic pathways used by sulfur-oxidizing bacteria.
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Since the beginning of unicellular life, dissimilation reactions of autotrophic sulfur bacteria have been a crucial part of the biogeochemical sulfur cycle on Earth. A wide range of sulfur oxidation states is reflected in the diversity of metabolic pathways used by sulfur-oxidizing bacteria. This metabolically and phylogenetically diverse group of microorganisms inhabits a variety of environments, including extreme environments. Although they have been of interest to microbiologists for more than 150 years, meso- and psychrophilic chemolithoautotrophic sulfur-oxidizing microbiota are less studied compared to the microbiota of hot springs. Several recent studies suggested that cold sulfur waters harbor unique, yet not described, bacterial taxa.
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(This article belongs to the Special Issue Latest Review Papers in Environmental Microbiology 2023)
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Open AccessArticle
Live Biomass of Rigidoporus vinctus: A Sustainable Method for Decoloration and Detoxification of Dyes in Water
by
, , , , , , and
Microorganisms 2023, 11(6), 1435; https://doi.org/10.3390/microorganisms11061435 - 29 May 2023
Abstract
In this study, white-rot fungus, Rigidoporus vinctus, collected from an unidentified fallen twig from Pathankot, Punjab, India, was used for biosorption of anionic Congo red and cationic Methylene blue dyes from an aqueous medium. The biosorption efficiency of the live biomass of
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In this study, white-rot fungus, Rigidoporus vinctus, collected from an unidentified fallen twig from Pathankot, Punjab, India, was used for biosorption of anionic Congo red and cationic Methylene blue dyes from an aqueous medium. The biosorption efficiency of the live biomass of Rigidoporus vinctus was investigated to optimize biosorbent dosage, process time, concentrations of dyes, and pH of solutions. The results indicated that Rigidoporus vinctus is more efficient than other reported bio-adsorbents for Congo red and Methylene blue dyes. The maximum biosorption activity of Rigidoporus vinctus for Congo red was found at pH 2, and that for Methylene blue was at pH 10, after 24 h of the reaction period. The process followed pseudo-second-order kinetics, which indicated that the interaction of both dyes to the adsorption sites on the surface of Rigidoporus vinctus was responsive to biosorption. The biosorption process could be well explained by the Langmuir isotherm for both dyes. The maximum monolayer biosorption capacity of Rigidoporus vinctus for Congo red and Methylene blue was observed to be 54.0 mg/g and 80.6 mg/g, respectively. The seed germination test was carried out, and it was assessed that the toxicity of dyes was reduced up to significant levels. Based on the present experimental findings, it can be concluded that biosorption using the live biomass of Rigidoporus vinctus can effectively decolorize dye-containing wastewater, thus reducing the hazardous effects of dyes on human beings.
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(This article belongs to the Special Issue Microbial Ecosystems in Water and Wastewater Treatment)
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Open AccessCommunication
Age-Related Subgingival Colonization of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Parvimonas micra—A Pragmatic Microbiological Retrospective Report
Microorganisms 2023, 11(6), 1434; https://doi.org/10.3390/microorganisms11061434 - 29 May 2023
Abstract
The aim of this study was to compare data about the prevalence and proportions of the bacterial species Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Parvimonas micra in periodontitis pocket samples collected from young, <35 years, and old, >35-year-old patients, YP and OP,
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The aim of this study was to compare data about the prevalence and proportions of the bacterial species Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Parvimonas micra in periodontitis pocket samples collected from young, <35 years, and old, >35-year-old patients, YP and OP, respectively. The results from the analyses of a total of 3447 subgingival plaque samples analyzed for clinical diagnosis purposes by cultivation regarding the proportions of these species were collected from a database and elucidated. The prevalence of A. actinomycetemcomitans was found to be more than twice as high (OR = 2.96, 95% CI; 2.50–3.50) in samples from the younger (42.2%) than the older group (20.4%) (p < 0.001). The prevalence of P. micra was significantly lower in samples from the younger age group (OR = 0.43, 95%) (p < 0.001), whereas P. gingivalis was similarly distributed (OR = 0.78, 95%) in the two age groups (p = 0.006). A similar pattern was noticed for A. actinomycetemcomitans and P. gingivalis when high proportions (>50%) of the samples of these bacterial species were elucidated. In contrast, the proportion of samples containing >50% with P. micra was lower compared with the two other bacterial species. Furthermore, it was noted that the proportion of samples from old patients containing A. actinomycetemcomitans in combination with P. micra was almost three times higher than in samples when P. micra was replaced by P. gingivalis. In conclusion, A.actinomycetemcomitans showed an increased presence and proportion in samples from young patients compared with the old patients, while P. gingivalis was similarly distributed in the two age groups. P. micra showed an increased presence and proportion in samples from old patients compared with the young patients.
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(This article belongs to the Special Issue Interaction between Oral Microbiota and Immunity in Health and Diseases)
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Open AccessArticle
Epidemiology of Zoonotic Coxiella burnetii in The Republic of Guinea
Microorganisms 2023, 11(6), 1433; https://doi.org/10.3390/microorganisms11061433 - 29 May 2023
Abstract
Background: Q fever is a zoonotic infectious disease characterized by fever, malaise, chills, significant weakness, and muscle pain. In some cases, the disease can become chronic and affect the inner membranes of the heart, such as the valves, leading to endocarditis and a
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Background: Q fever is a zoonotic infectious disease characterized by fever, malaise, chills, significant weakness, and muscle pain. In some cases, the disease can become chronic and affect the inner membranes of the heart, such as the valves, leading to endocarditis and a high risk of death. Coxiella burnetii (C. burnetii) is the primary causative agent of Q fever in humans. This study aims to monitor the presence of C. burnetii in ticks collected from small mammals and cattle in the Republic of Guinea (RG). Methods: Rodents were trapped in the Kindia region of RG during 2019–2020, and ticks were collected from cattle in six regions of RG. Total DNA was extracted using a commercial kit (RIBO-prep, InterLabService, Russia) following the manufacturer’s instructions. Real-time PCR amplification was conducted using the kit (AmpliSens Coxiella burnetii-FL, InterLabService, Russia) to detect C. burnetii DNA. Results and Conclusions: Bacterial DNA was detected in 11 out of 750 (1.4%) small mammals and 695 out of 9620 (7.2%) tick samples. The high number of infected ticks (7.2%) suggests that they are the main transmitters of C. burnetii in RG. The DNA was detected in the liver and spleen of a Guinea multimammate mouse, Mastomys erythroleucus. These findings demonstrate that C. burnetii is zoonotic in RG, and measures should be taken to monitor the bacteria’s dynamics and tick prevalence in the rodent population.
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(This article belongs to the Special Issue Intracellular Bacteria: From Basic Research to Clinics 2.0)
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Comparative Genomic Analysis of Multi-Drug Resistant Pseudomonas aeruginosa Sequence Type 235 Isolated from Sudan
by
, , , , , , , , , , , , and
Microorganisms 2023, 11(6), 1432; https://doi.org/10.3390/microorganisms11061432 - 29 May 2023
Abstract
Pseudomonas aeruginosa (P. aeruginosa) is known to be associated with resistance to practically all known antibiotics. This is a cross-sectional, descriptive, laboratory-based analytical study in which 200 P. aeruginosa clinical isolates were involved. The DNA of the most resistant isolate was extracted
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Pseudomonas aeruginosa (P. aeruginosa) is known to be associated with resistance to practically all known antibiotics. This is a cross-sectional, descriptive, laboratory-based analytical study in which 200 P. aeruginosa clinical isolates were involved. The DNA of the most resistant isolate was extracted and its whole genome was sequenced, assembled, annotated, and announced, strain typing was ascribed, and it was subjected to comparative genomic analysis with two susceptible strains. The rate of resistance was 77.89%, 25.13%, 21.61%, 18.09%, 5.53%, and 4.52% for piperacillin, gentamicin, ciprofloxacin, ceftazidime, meropenem, and polymyxin B, respectively. Eighteen percent (36) of the tested isolates exhibited a MDR phenotype. The most MDR strain belonged to epidemic sequence type 235. Comparative genomic analysis of the MDR strain (GenBank: MVDK00000000) with two susceptible strains revealed that the core genes were shared by the three genomes but there were accessory genes that were strain-specific, and this MDR genome had a low CG% (64.6%) content. A prophage sequence and one plasmid were detected in the MDR genome, but amazingly, it contained no resistant genes for drugs with antipseudomonal activity and there was no resistant island. In addition, 67 resistant genes were detected, 19 of them were found only in the MDR genome and 48 genes were efflux pumps, and a novel deleterious point mutation (D87G) was detected in the gyrA gene. The novel deleterious mutation in the gyrA gene (D87G) is a known position behind quinolone resistance. Our findings emphasize the importance of adoption of infection control strategies to prevent dissemination of MDR isolates.
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(This article belongs to the Special Issue Advances in Antibiotic and Antifungal Resistance and Related Alternative Therapies)
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Identification of a New Pathogenic fungi Causing Sorghum Leaf Spot Disease and Its Management Using Natural Product and Microorganisms
Microorganisms 2023, 11(6), 1431; https://doi.org/10.3390/microorganisms11061431 - 29 May 2023
Abstract
Sorghum bicolor is cultivated worldwide. Leaf spot of sorghum, which leads to leaf lesions and yield reduction, is a prevalent and serious disease in Guizhou Province, southwest China. In August 2021, new leaf spot symptoms were observed on sorghum leaves. In this study,
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Sorghum bicolor is cultivated worldwide. Leaf spot of sorghum, which leads to leaf lesions and yield reduction, is a prevalent and serious disease in Guizhou Province, southwest China. In August 2021, new leaf spot symptoms were observed on sorghum leaves. In this study, traditional methods and modern molecular biology techniques were used to isolate and identify the pathogen. Sorghum inoculated with the isolate GY1021 resulted in reddish brown lesion that similar to symptoms observed in the field: the original isolate inoculated was reisolated and Koch’s postulates were fulfilled. Based on morphological features and phylogenetic analysis of the internal transcribed spacer (ITS) combined sequence with β-tubulin (TUB2) and translation elongation factor 1-α (TEF-1α) genes, the isolate was identified as Fusarium thapsinum (Strain accession: GY 1021; GenBank Accession: ITS (ON882046), TEF-1α (OP096445), and β-TUB (OP096446)). Then, we studied the bioactivity of various natural products and microorganisms against F. thapsinum using the dual culture experiment. Carvacrol, 2-allylphenol, honokiol, and cinnamaldehyde showed excellent antifungal activity, with EC50 values of 24.19, 7.18, 46.18, and 52.81 µg/mL, respectively. The bioactivity of six antagonistic bacteria was measured using a dual culture experiment and the mycelial growth rate method. Paenibacillus polymyxa, Bacillus amyloliquefaciens and Bacillus velezensis displayed significant antifungal effects against F. thapsinum. This study provides a theoretical basis for the green control of leaf spot of sorghum.
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(This article belongs to the Special Issue The Bacteriostatic Effect and Mechanism of Microbial Secondary Metabolites)
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