31 pages, 2087 KiB  
Review
The Role of Coagulase-Negative Staphylococci Biofilms on Late-Onset Sepsis: Current Challenges and Emerging Diagnostics and Therapies
by Angela França 1,2
1 Centre of Biological Engineering, LIBRO—Laboratório de Investigação em Biofilmes Rosário Oliveira, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
2 LABBELS—Associate Laboratory in Biotechnology and Bioengineering and Microelectromechanical Systems, Braga and Guimarães, Portugal
Antibiotics 2023, 12(3), 554; https://doi.org/10.3390/antibiotics12030554 - 10 Mar 2023
Cited by 17 | Viewed by 7967
Abstract
Infections are one of the most significant complications of neonates, especially those born preterm, with sepsis as one of the principal causes of mortality. Coagulase-negative staphylococci (CoNS), a group of staphylococcal species that naturally inhabit healthy human skin and mucosa, are the most [...] Read more.
Infections are one of the most significant complications of neonates, especially those born preterm, with sepsis as one of the principal causes of mortality. Coagulase-negative staphylococci (CoNS), a group of staphylococcal species that naturally inhabit healthy human skin and mucosa, are the most common cause of late-onset sepsis, especially in preterms. One of the risk factors for the development of CoNS infections is the presence of implanted biomedical devices, which are frequently used for medications and/or nutrient delivery, as they serve as a scaffold for biofilm formation. The major concerns related to CoNS infections have to do with the increasing resistance to multiple antibiotics observed among this bacterial group and biofilm cells’ increased tolerance to antibiotics. As such, the treatment of CoNS biofilm-associated infections with antibiotics is increasingly challenging and considering that antibiotics remain the primary form of treatment, this issue will likely persist in upcoming years. For that reason, the development of innovative and efficient therapeutic measures is of utmost importance. This narrative review assesses the current challenges and emerging diagnostic tools and therapies for the treatment of CoNS biofilm-associated infections, with a special focus on late-onset sepsis. Full article
(This article belongs to the Special Issue Feature Reviews on Antibiofilm Strategies)
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15 pages, 4283 KiB  
Article
Antimicrobial Peptides Designed against the Ω-Loop of Class A β-Lactamases to Potentiate the Efficacy of β-Lactam Antibiotics
by Sarmistha Biswal 1,2, Karina Caetano 2, Diamond Jain 1, Anusha Sarrila 1, Tulika Munshi 2,†, Rachael Dickman 3,4, Alethea B. Tabor 3, Surya Narayan Rath 5, Sanjib Bhakta 2,* and Anindya S. Ghosh 1,*
1 Molecular Microbiology Laboratory, Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India
2 Mycobacteria Research Laboratory, Institute of Structural and Molecular Biology, Department of Biological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK
3 Department of Chemistry, University College London, Gordon Street, London WC1H 0AJ, UK
4 School of Pharmacy, University College London, Brunswick Square, London WC1N 1AX, UK
5 Department of Bioinformatics, Odisha University of Agriculture and Technology, Bhubaneswar 751003, Odisha, India
Current Address: Institute for Infection and Immunity, St George’s, University of London, Cranmer Terrace, London SW17 0RE, UK.
Antibiotics 2023, 12(3), 553; https://doi.org/10.3390/antibiotics12030553 - 10 Mar 2023
Cited by 4 | Viewed by 3609
Abstract
Class A serine β-lactamases (SBLs) have a conserved non-active site structural domain called the omega loop (Ω-loop), in which a glutamic acid residue is believed to be directly involved in the hydrolysis of β-lactam antibiotics by providing a water molecule during catalysis. We [...] Read more.
Class A serine β-lactamases (SBLs) have a conserved non-active site structural domain called the omega loop (Ω-loop), in which a glutamic acid residue is believed to be directly involved in the hydrolysis of β-lactam antibiotics by providing a water molecule during catalysis. We aimed to design and characterise potential pentapeptides to mask the function of the Ω-loop of β-lactamases and reduce their efficacy, along with potentiating the β-lactam antibiotics and eventually decreasing β-lactam resistance. Considering the Ω-loop sequence as a template, a group of pentapeptide models were designed, validated through docking, and synthesised using solid-phase peptide synthesis (SPPS). To check whether the β-lactamases (BLAs) were inhibited, we expressed specific BLAs (TEM-1 and SHV-14) and evaluated the trans-expression through a broth dilution method and an agar dilution method (HT-SPOTi). To further support our claim, we conducted a kinetic analysis of BLAs with the peptides and employed molecular dynamics (MD) simulations of peptides. The individual presence of six histidine-based peptides (TSHLH, ETHIH, ESRLH, ESHIH, ESRIH, and TYHLH) reduced β-lactam resistance in the strains harbouring BLAs. Subsequently, we found that the combinational effect of these peptides and β-lactams sensitised the bacteria towards the β-lactam drugs. We hypothesize that the antimicrobial peptides obtained might be considered among the novel inhibitors that can be used specifically against the Ω-loop of the β-lactamases. Full article
(This article belongs to the Section Novel Antimicrobial Agents)
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18 pages, 351 KiB  
Article
Building an International One Health Strain Level Database to Characterise the Epidemiology of AMR Threats: ESBL—AmpC Producing E. coli as An Example—Challenges and Perspectives
by Sara Perestrelo 1, Ana Amaro 2, Michael S. M. Brouwer 3, Lurdes Clemente 2, Ana Sofia Ribeiro Duarte 4, Annemarie Kaesbohrer 1,5, Renata Karpíšková 6, Vicente Lopez-Chavarrias 7, Dearbháile Morris 8, Deirdre Prendergast 9, Angela Pista 10, Leonor Silveira 10, Magdalena Skarżyńska 11, Rosemarie Slowey 9, Kees T. Veldman 3, Magdalena Zając 11, Catherine Burgess 12,† and Julio Alvarez 7,13,*,†
1 Department of Biological Safety, German Federal Institute for Risk Assessment, 10589 Berlin, Germany
2 Laboratory of Bacteriology and Micology, National Institute of Agrarian and Veterinary Research, National Reference for Animal Health, 2780-157 Oeiras, Portugal
3 Department of Bacteriology, Host Pathogen Interaction & Diagnostics, Wageningen Bioveterinary Research, Part of Wageningen University & Research, 8221 Lelystad, The Netherlands
4 National Food Institute, Technical University of Denmark, 2800 Kongens Lyngby, Denmark
5 Veterinary Public Health and Epidemiology, University of Veterinary Medicine, 1210 Vienna, Austria
6 Department of Public Health, Medical Faculty, Masaryk University, 625 000 Brno, Czech Republic
7 VISAVET Health Surveillance Centre, Universidad Complutense, 28040 Madrid, Spain
8 Antimicrobial Resistance and Microbial Ecology Group, School of Medicine, University of Galway, H91 TK33 Galway, Ireland
9 Backweston Laboratory Campus, Department of Agriculture, Food and the Marine, W23 X3PH Celbridge, Ireland
10 National Reference Laboratory for Gastrointestinal Infections, Department of Infectious Diseases, National Institute of Health Doutor Ricardo Jorge, Avenida Padre Cruz, 1649-016 Lisbon, Portugal
11 Department of Microbiology, National Veterinary Research Institute, 24-100 Pulawy, Poland
12 Food Safety Department, Teagasc Food Research Centre Ashtown, D15 DY05 Dublin, Ireland
13 Department of Animal Health, Faculty of Veterinary Medicine, Universidad Complutense, Avda. Puerta de Hierro S/N, 28040 Madrid, Spain
These authors contributed equally to this work.
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Antibiotics 2023, 12(3), 552; https://doi.org/10.3390/antibiotics12030552 - 10 Mar 2023
Cited by 16 | Viewed by 4859
Abstract
Antimicrobial resistance (AMR) is one of the top public health threats nowadays. Among the most important AMR pathogens, Escherichia coli resistant to extended spectrum cephalosporins (ESC-EC) is a perfect example of the One Health problem due to its global distribution in animal, human, [...] Read more.
Antimicrobial resistance (AMR) is one of the top public health threats nowadays. Among the most important AMR pathogens, Escherichia coli resistant to extended spectrum cephalosporins (ESC-EC) is a perfect example of the One Health problem due to its global distribution in animal, human, and environmental sources and its resistant phenotype, derived from the carriage of plasmid-borne extended-spectrum and AmpC β-lactamases, which limits the choice of effective antimicrobial therapies. The epidemiology of ESC-EC infection is complex as a result of the multiple possible sources involved in its transmission, and its study would require databases ideally comprising information from animal (livestock, companion, wildlife), human, and environmental sources. Here, we present the steps taken to assemble a database with phenotypic and genetic information on 10,763 ESC-EC isolates retrieved from multiple sources provided by 13 partners located in eight European countries, in the frame of the DiSCoVeR Joint Research project funded by the One Health European Joint Programme (OH-EJP), along with its strengths and limitations. This database represents a first step to help in the assessment of different geographical and temporal trends and transmission dynamics in animals and humans. The work performed highlights aspects that should be considered in future international efforts, such as the one presented here. Full article
(This article belongs to the Special Issue Epidemiology of ESBL-Producing Enterobacteriaceae)
18 pages, 2648 KiB  
Article
Comparative Evaluation of Existing and Rationally Designed Novel Antimicrobial Peptides for Treatment of Skin and Soft Tissue Infections
by Anna Ramata-Stunda 1,*, Martins Boroduskis 1, Elza Kaktina 1, Liene Patetko 2, Uldis Kalnenieks 1,3, Zane Lasa 3, Marta Rubina 3, Inese Strazdina 3, Gints Kalnins 4 and Reinis Rutkis 3
1 Alternative Plants Ltd., 2 Podraga Str., LV-1007 Riga, Latvia
2 Laboratory of Bioanalytical and Biodosimetry Methods, Faculty of Biology, University of Latvia, 3 Jelgavas Str., LV-1004 Riga, Latvia
3 Institute of Microbiology and Biotechnology, University of Latvia, 1 Jelgavas Str., LV-1004 Riga, Latvia
4 Latvian Biomedical Research and Study Centre, 1 Ratsupites Str., LV-1067 Riga, Latvia
Antibiotics 2023, 12(3), 551; https://doi.org/10.3390/antibiotics12030551 - 10 Mar 2023
Cited by 4 | Viewed by 3410
Abstract
Skin and soft tissue infections (SSTIs) and acne are among the most common skin conditions in primary care. SSTIs caused by ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter sp.) can [...] Read more.
Skin and soft tissue infections (SSTIs) and acne are among the most common skin conditions in primary care. SSTIs caused by ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter sp.) can range in severity, and treating them is becoming increasingly challenging due to the growing number of antibiotic-resistant pathogens. There is also a rise in antibiotic-resistant strains of Cutibacterium acne, which plays a role in the development of acne. Antimicrobial peptides (AMPs) are considered to be a promising solution to the challenges posed by antibiotic resistance. In this study, six new AMPs were rationally designed and compared to five existing peptides. The MIC values against E. coli, P. aeruginosa, K. pneumoniae, E. faecium, S. aureus, and C. acnes were determined, and the peptides were evaluated for cytotoxicity using Balb/c 3T3 cells and dermal fibroblasts, as well as for hemolytic activity. The interaction with bacterial membranes and the effect on TNF-α and IL-10 secretion were also evaluated for selected peptides. Of the tested peptides, RP556 showed high broad-spectrum antibacterial activity without inducing cytotoxicity or hemolysis, and it stimulated the production of IL-10 in LPS-stimulated peripheral blood mononuclear cells. Four of the novel AMPs showed pronounced specificity against C. acnes, with MIC values (0.3–0.5 μg/mL) below the concentrations that were cytotoxic or hemolytic. Full article
(This article belongs to the Special Issue Antimicrobial Peptides from Natural Sources to Synthetic Optimization)
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21 pages, 2470 KiB  
Review
Antibiotic Resistance and Food Safety: Perspectives on New Technologies and Molecules for Microbial Control in the Food Industry
by Jannette Wen Fang Wu-Wu 1,*, Carolina Guadamuz-Mayorga 2, Douglas Oviedo-Cerdas 3 and William J. Zamora 4,5,6,7
1 Food Technology Department, University of Costa Rica, San José 11501-2060, Costa Rica
2 Agribusiness Department, Costa Rican Technological Institute, Cartago 159-7050, Costa Rica
3 Instrumental Analysis Department, Iberoamerican University, Tibás 11870-1000, Costa Rica
4 CBio3 Laboratory, School of Chemistry, University of Costa Rica, San Pedro, San José 11501-2060, Costa Rica
5 Laboratory of Computational Toxicology, University of Costa Rica, San Pedro, San José 11501-2060, Costa Rica
6 Biological Testing Laboratory (LEBi), University of Costa Rica, San Pedro, San José 11501-2060, Costa Rica
7 Advanced Computing Lab (CNCA), National High Technology Center (CeNAT), Pavas, San José 1174-1200, Costa Rica
Antibiotics 2023, 12(3), 550; https://doi.org/10.3390/antibiotics12030550 - 10 Mar 2023
Cited by 55 | Viewed by 9789
Abstract
Antibiotic resistance (ABR) has direct and indirect repercussions on public health and threatens to decrease the therapeutic effect of antibiotic treatments and lead to more infection-related deaths. There are several mechanisms by which ABR can be transferred from one microorganism to another. The [...] Read more.
Antibiotic resistance (ABR) has direct and indirect repercussions on public health and threatens to decrease the therapeutic effect of antibiotic treatments and lead to more infection-related deaths. There are several mechanisms by which ABR can be transferred from one microorganism to another. The risk of transfer is often related to environmental factors. The food supply chain offers conditions where ABR gene transfer can occur by multiple pathways, which generates concerns regarding food safety. This work reviews mechanisms involved in ABR gene transfer, potential transmission routes in the food supply chain, the prevalence of antibiotic residues in food and ABR organisms in processing lines and final products, and implications for public health. Finally, the paper will elaborate on the application of antimicrobial peptides as new alternatives to antibiotics that might countermeasure ABR and is compatible with current food trends. Full article
(This article belongs to the Special Issue Foodborne Pathogens: Features of Virulence and Antibiotic Resistance)
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12 pages, 4314 KiB  
Article
Anti-Inflammatory Activity of Glyceryl 1,3-Distearate Identified from Clinacanthus nutans Extract against Bovine Mastitis Pathogens
by Saruda Thongyim 1, Salinee Chiangchin 2, Hataichanok Pandith 2,3, Yingmanee Tragoolpua 2,3, Siriphorn Jangsutthivorawat 2,3 and Aussara Panya 2,3,*
1 Doctor of Philosophy Program in Biology (International Program), Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
2 Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
3 Research Center in Bioresources for Agriculture, Industry and Medicine, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
Antibiotics 2023, 12(3), 549; https://doi.org/10.3390/antibiotics12030549 - 9 Mar 2023
Cited by 9 | Viewed by 2381
Abstract
Clinacanthus nutans is widely used as a traditional medicine in Thailand and other countries in Southeast Asia. Although its effectiveness is well documented, its therapeutic use is limited to the treatment of only a few diseases; mostly it is used as an anti-viral [...] Read more.
Clinacanthus nutans is widely used as a traditional medicine in Thailand and other countries in Southeast Asia. Although its effectiveness is well documented, its therapeutic use is limited to the treatment of only a few diseases; mostly it is used as an anti-viral agent against varicella-zoster and herpes simplex virus infections. Herein, we demonstrate the therapeutic activity of C. nutans extracts in lowering inflammation in a model of bovine mastitis caused by bacterial infection. Lipopolysaccharide (LPS), a gram-negative bacterial component, caused inflammation activation in bovine endothelial cells (CPAE) through the upregulation of proinflammatory cytokines (IL6 and IL1β) and chemokines (CXCL3 and CXCL8) gene expression, partially leading to cell death. Treatment with C. nutans crude extract significantly diminished these responses in a dose-dependent manner. The solvent fractionation of C. nutans extract revealed that the ethyl acetate (C4H8O2) fractions had a high potential to protect against cell death and diminished IL1β, IL6, CXCL3, and CXCL8 levels to less than 0.45 folds relative to the LPS-treated control. Glyceryl 1,3-distearate (C39H76O5) was identified as a bioactive compound responsible for the anti-inflammation activity but not the anti-cell death activity of C. nutans extract. This study highlighted the efficiency of C. nutans extracts as an alternative therapeutic option for the natural-product sustainable development of bovine mastitis treatment. Full article
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18 pages, 1351 KiB  
Systematic Review
Antibiotic Resistance in Campylobacter: A Systematic Review of South American Isolates
by Ana Beatriz Portes 1,2,3, Pedro Panzenhagen 1,2,4,*, Anamaria Mota Pereira dos Santos 1,2,3 and Carlos Adam Conte Junior 1,2,3,4,5,6,7
1 Center for Food Analysis (NAL), Technological Development Support Laboratory (LADETEC), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-598, Brazil
2 Laboratory of Advanced Analysis in Biochemistry and Molecular Biology (LAABBM), Department of Biochemistry, Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, Brazil
3 Graduate Program in Veterinary Hygiene and Technological Processing (PGHIGVET), Faculty of Veterinary Medicine, Fluminense Federal University (UFF), Vital Brazil Filho, Niterói 24220-000, Brazil
4 Analytical and Molecular Laboratorial Center (CLAn), Institute of Chemistry (IQ), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, Brazil
5 Graduate Program in Food Science (PPGCAL), Institute of Chemistry (IQ), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, Brazil
6 Graduate Program in Sanitary Surveillance (PPGVS), National Institute of Health Quality Control (INCQS), Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro 21040-900, Brazil
7 Graduate Program in Chemistry (PGQu), Institute of Chemistry (IQ), Federal University of Rio de Janeiro (UFRJ), Cidade Universitária, Rio de Janeiro 21941-909, Brazil
Antibiotics 2023, 12(3), 548; https://doi.org/10.3390/antibiotics12030548 - 9 Mar 2023
Cited by 40 | Viewed by 6009
Abstract
In recent years, Campylobacter has become increasingly resistant to antibiotics, especially those first-choice drugs used to treat campylobacteriosis. Studies in South America have reported cases of antibiotic-resistant Campylobacter in several countries, mainly in Brazil. To understand the current frequency of antibiotic-resistant Campylobacter in [...] Read more.
In recent years, Campylobacter has become increasingly resistant to antibiotics, especially those first-choice drugs used to treat campylobacteriosis. Studies in South America have reported cases of antibiotic-resistant Campylobacter in several countries, mainly in Brazil. To understand the current frequency of antibiotic-resistant Campylobacter in humans, farm animals, and food of animal origin in South America, we systematically searched for different studies that have reported Campylobacter resistance. The most commonly reported species were C. jejuni and C. coli. Resistance to ciprofloxacin was found to be ubiquitous in the isolates. Nalidixic acid and tetracycline showed a significantly expressed resistance. Erythromycin, the antibiotic of first choice for the treatment of campylobacteriosis, showed a low rate of resistance in isolates but was detected in almost all countries. The main sources of antibiotic-resistant Campylobacter isolates were food of animal origin and farm animals. The results demonstrate that resistant Campylobacter isolates are disseminated from multiple sources linked to animal production in South America. The level of resistance that was identified may compromise the treatment of campylobacteriosis in human and animal populations. In this way, we are here showing all South American communities the need for the constant surveillance of Campylobacter resistance and the need for the strategic use of antibiotics in animal production. These actions are likely to decrease future difficulties in the treatment of human campylobacteriosis. Full article
(This article belongs to the Special Issue Antimicrobial Resistance and Virulence – 3rd Volume)
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13 pages, 2201 KiB  
Article
Spread of blaCTX-M-9 and Other Clinically Relevant Resistance Genes, Such as mcr-9 and qnrA1, Driven by IncHI2-ST1 Plasmids in Clinical Isolates of Monophasic Salmonella enterica Serovar Typhimurium ST34
by Xenia Vázquez 1,2, Javier Fernández 2,3,4,5, Miriam Alkorta 6, María de Toro 7, M. Rosario Rodicio 1,2,*,† and Rosaura Rodicio 2,8,*,†
1 Departamento de Biología Funcional, Área de Microbiología, Universidad de Oviedo (UO), 33006 Oviedo, Spain
2 Grupo de Microbiología Traslacional, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
3 Servicio de Microbiología, Hospital Universitario Central de Asturias (HUCA), 33011 Oviedo, Spain
4 Centro de Investigación Biomédica en Red-Enfermedades Respiratorias, 30627 Madrid, Spain
5 Research & Innovation, Artificial Intelligence and Statistical Department, Pragmatech AI Solutions, 33001 Oviedo, Spain
6 Servicio de Microbiología, Hospital Universitario de Donostia (HUD)-IIS Biodonostia, 20014 San Sebastián, Spain
7 Plataforma de Genómica y Bioinformática, Centro de Investigación Biomédica de La Rioja (CIBIR), 26006 Logroño, Spain
8 Departamento de Bioquímica y Biología Molecular, Universidad de Oviedo (UO), 33006 Oviedo, Spain
These authors contributed equally to this work.
Antibiotics 2023, 12(3), 547; https://doi.org/10.3390/antibiotics12030547 - 9 Mar 2023
Cited by 5 | Viewed by 2602
Abstract
The monophasic 4,[5],12:i:-variant of Salmonella enterica serovar Typhimurium with sequence type ST34 has become one of the most prevalent non-typhoidal salmonellae worldwide. In the present study, we thoroughly characterized seven isolates of this variant detected in a Spanish hospital and selected based on [...] Read more.
The monophasic 4,[5],12:i:-variant of Salmonella enterica serovar Typhimurium with sequence type ST34 has become one of the most prevalent non-typhoidal salmonellae worldwide. In the present study, we thoroughly characterized seven isolates of this variant detected in a Spanish hospital and selected based on cefotaxime resistance and cefoxitin susceptibility, mediated by blaCTX-M-9. For this, conventional microbiological techniques, together with whole genome sequencing performed with the Illumina platform, were applied. All selected isolates carried the resistance region RR or variants therein, and most also contained the SGI-4 genomic island. These chromosomal elements, typically associated with monophasic S. Typhimurium ST34, confer resistance to traditional antibiotics (ampicillin, streptomycin, sulfonamides, and tetracycline) and tolerance to heavy metals (mercury, silver, and copper). In addition, each isolate carried a large IncHI2-ST1 conjugative plasmid containing additional or redundant resistance genes. All harbored the blaCTX-M-9 gene responsible for cefotaxime resistance, whereas the qnrA1 gene mediating fluoroquinolone resistance was detected in two of the plasmids. These genes were embedded in ISCR1-bearing complex class 1 integrons, specifically In60-like and In36-like. The mcr-9 gene was present in all but one of the IncHI2-ST1 plasmids found in the analyzed isolates, which were nevertheless susceptible to colistin. Most of the resistance genes of plasmid origin clustered within a highly complex and variable region. The observed diversity results in a wide range of resistance phenotypes, enabling bacterial adaptation to selective pressure posed by the use of antimicrobials. Full article
(This article belongs to the Special Issue Genetic Background of Antimicrobial Resistance)
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13 pages, 3782 KiB  
Article
Monensin, an Antibiotic Isolated from Streptomyces Cinnamonensis, Regulates Human Neuroblastoma Cell Proliferation via the PI3K/AKT Signaling Pathway and Acts Synergistically with Rapamycin
by Sema Serter Kocoglu 1,*, Mücahit Secme 2, Ceren Oy 3, Gözde Korkusuz 1 and Levent Elmas 4
1 Department of Histology and Embryology, Faculty of Medicine, Balikesir University, Balikesir 10145, Turkey
2 Department of Medical Biology, Faculty of Medicine, Ordu University, Ordu 52000, Turkey
3 Department of Histology and Embryology, Faculty of Medicine, Bursa Uludag University, Bursa 16059, Turkey
4 Department of Medical Biology, Faculty of Medicine, Bakırçay University, İzmir 35665, Turkey
Antibiotics 2023, 12(3), 546; https://doi.org/10.3390/antibiotics12030546 - 9 Mar 2023
Cited by 6 | Viewed by 2851
Abstract
Neuroblastoma is the most common extracranial childhood tumor and accounts for approximately 15% of pediatric cancer-related deaths. Further studies are needed to identify potential therapeutic targets for neuroblastoma. Monensin is an ionophore antibiotic obtained from Streptomyces cinnamonensis with known antibacterial and antiparasitic effects. [...] Read more.
Neuroblastoma is the most common extracranial childhood tumor and accounts for approximately 15% of pediatric cancer-related deaths. Further studies are needed to identify potential therapeutic targets for neuroblastoma. Monensin is an ionophore antibiotic obtained from Streptomyces cinnamonensis with known antibacterial and antiparasitic effects. No study has reported the effects of monensin on SH-SY5Y neuroblastoma cells by targeting the PI3K/AKT signaling pathway. The aim of this study was to investigate the antiproliferative effects of monensin alone and in combination with rapamycin in human SH-SY5Y neuroblastoma cells mediated by the PI3K/AKT signaling pathway. The effects of single and combination applications of monensin and rapamycin on SH-SY5Y cell proliferation were investigated by XTT, and their effects on the PI3K/AKT signaling pathway by RT-PCR, immunohistochemistry, immunofluorescence, and Western blotting. The combined effects of monensin and rapamycin on SH-SY5Y proliferation were most potent at 72 h (combination index < 1). The combination of monensin and rapamycin caused a significant decrease in the expression of P21RAS, AKT, and MAPK1 genes. Single and combined administrations of monensin and rapamycin caused a significant decrease in PI3K/AKT expression. Our results showed for the first time that monensin exerts an antiproliferative effect by targeting the PI3K/AKT signaling pathway in neuroblastoma cells. It is suggested that monensin and its combination with rapamycin may be an effective therapeutic candidate for treating neuroblastoma. Full article
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18 pages, 3404 KiB  
Article
The Anti-Biofilm Potential of Linalool, a Major Compound from Hedychium larsenii, against Streptococcus pyogenes and Its Toxicity Assessment in Danio rerio
by Sarath Praseetha 1, Swapna Thacheril Sukumaran 2, Mathew Dan 3, Akshaya Rani Augustus 4, Shunmugiah Karutha Pandian 4 and Shiburaj Sugathan 2,*
1 Department of Biotechnology, Kariavattom Campus, University of Kerala, Thiruvananthapuram Pin-695 581, Kerala, India
2 Department of Botany, Kariavattom Campus, University of Kerala, Thiruvananthapuram Pin-695 581, Kerala, India
3 Plant Genetic Resource Division, Jawaharlal Nehru Tropical Botanic Garden & Research Institute, Palode, Thiruvananthapuram Pin-695 562, Kerala, India
4 Department of Biotechnology, Alagappa University, Karaikudi Pin-630 003, Tamil Nadu, India
Antibiotics 2023, 12(3), 545; https://doi.org/10.3390/antibiotics12030545 - 9 Mar 2023
Cited by 12 | Viewed by 2780
Abstract
The anti-biofilm and anti-virulence potential of the essential oil (E.O.) extracted from Hedychium larsenii M. Dan & Sathish was determined against Streptococcus pyogenes. A crystal violet assay was employed to quantify the biofilm. Linalool, a monoterpene alcohol from the E.O., showed concentration-dependent [...] Read more.
The anti-biofilm and anti-virulence potential of the essential oil (E.O.) extracted from Hedychium larsenii M. Dan & Sathish was determined against Streptococcus pyogenes. A crystal violet assay was employed to quantify the biofilm. Linalool, a monoterpene alcohol from the E.O., showed concentration-dependent biofilm inhibition, with a maximum of 91% at a concentration of 0.004% (v/v). The AlamarBlueTM assay also confirmed Linalool’s non-bactericidal anti-biofilm efficacy (0.004%). Linalool treatment impeded micro-colony formation, mature biofilm architecture, surface coverage, and biofilm thickness and impaired cell surface hydrophobicity and EPS production. Cysteine protease synthesis was quantified using the Azocasein assay, and Linalool treatment augmented its production. This suggests that Linalool destabilizes the biofilm matrix. It altered the expression of core regulons covRS, mga, srv, and ropB, and genes associated with virulence and biofilm formation, such as speB, dltA, slo, hasA, and ciaH, as revealed by qPCR analysis. Cytotoxicity analysis using human kidney cells (HEK) and the histopathological analysis in Danio rerio proved Linalool to be a druggable molecule against the biofilms formed by S. pyogenes. This is the first report on Linalool’s anti-biofilm and anti-virulence potential against S. pyogenes. Full article
(This article belongs to the Special Issue Novel Antimicrobial Agents to Inhibit Microbial Conglomerates)
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16 pages, 4477 KiB  
Article
Genomic Analysis Reveals New Integrative Conjugal Elements and Transposons in GBS Conferring Antimicrobial Resistance
by Uzma Basit Khan 1,2, Edward A. R. Portal 1,3,4, Kirsty Sands 1,4, Stephanie Lo 2, Victoria J. Chalker 3, Elita Jauneikaite 5,6,*,† and Owen B. Spiller 1,3,*,†
1 Department of Medical Microbiology, Division of Infection and Immunity, Cardiff University, 6th Floor University Hospital of Wales, Cardiff CF14 4XN, UK
2 Parasites and Microbes Programme, The Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge CB10 1SA, UK
3 Bacterial Reference Department, UK Health Security Agency, London NW9 5DF, UK
4 Department of Biology, Ineos Oxford Institute, University of Oxford, Oxford OX1 3RE, UK
5 NIHR Health Protection Research Unit in Healthcare Associated Infections and Antimicrobial Resistance, Department of Infectious Disease, Imperial College London, London W12 0NN, UK
6 Department of Infectious Disease Epidemiology, School of Public Health, Imperial College London, London W2 1PG, UK
These authors contributed equally to this work.
Antibiotics 2023, 12(3), 544; https://doi.org/10.3390/antibiotics12030544 - 9 Mar 2023
Cited by 15 | Viewed by 3708
Abstract
Streptococcus agalactiae or group B streptococcus (GBS) is a leading cause of neonatal sepsis and increasingly found as an invasive pathogen in older patient populations. Beta-lactam antibiotics remain the most effective therapeutic with resistance rarely reported, while the majority of GBS isolates carry [...] Read more.
Streptococcus agalactiae or group B streptococcus (GBS) is a leading cause of neonatal sepsis and increasingly found as an invasive pathogen in older patient populations. Beta-lactam antibiotics remain the most effective therapeutic with resistance rarely reported, while the majority of GBS isolates carry the tetracycline resistance gene tet(M) in fixed genomic positions amongst five predominant clonal clades. In the UK, GBS resistance to clindamycin and erythromycin has increased from 3% in 1991 to 11.9% (clindamycin) and 20.2% (erythromycin), as reported in this study. Here, a systematic investigation of antimicrobial resistance genomic content sought to fully characterise the associated mobile genetic elements within phenotypically resistant GBS isolates from 193 invasive and non-invasive infections of UK adult patients collected during 2014 and 2015. Resistance to erythromycin and clindamycin was mediated by erm(A) (16/193, 8.2%), erm(B) (16/193, 8.2%), mef(A)/msr(D) (10/193, 5.1%), lsa(C) (3/193, 1.5%), lnu(C) (1/193, 0.5%), and erm(T) (1/193, 0.5%) genes. The integrative conjugative elements (ICEs) carrying these genes were occasionally found in combination with high gentamicin resistance mediating genes aac(6′)-aph(2″), aminoglycoside resistance genes (ant(6-Ia), aph(3′-III), and/or aad(E)), alternative tetracycline resistance genes (tet(O) and tet(S)), and/or chloramphenicol resistance gene cat(Q), mediating resistance to multiple classes of antibiotics. This study provides evidence of the retention of previously reported ICESag37 (n = 4), ICESag236 (n = 2), and ICESpy009 (n = 3), as well as the definition of sixteen novel ICEs and three novel transposons within the GBS lineage, with no evidence of horizontal transfer. Full article
(This article belongs to the Section Mechanism and Evolution of Antibiotic Resistance)
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41 pages, 1705 KiB  
Review
Green Synthesis of Bioinspired Nanoparticles Mediated from Plant Extracts of Asteraceae Family for Potential Biological Applications
by Juhi Puthukulangara Jaison 1,†, Balamuralikrishnan Balasubramanian 2,†, Jaya Gangwar 1, Nilina James 1, Manikantan Pappuswamy 1, Arumugam Vijaya Anand 3, Naif Abdullah Al-Dhabi 4, Mariadhas Valan Arasu 4, Wen-Chao Liu 5,* and Joseph Kadanthottu Sebastian 1,*
1 Department of Life Sciences, School of Sciences, Christ University, Bangalore 560029, India
2 Department of Food Science and Biotechnology, College of Life Science, Sejong University, Seoul 05006, Republic of Korea
3 Department of Human Genetics and Molecular Biology, Bharathiar University, Coimbatore 641046, India
4 Department of Botany and Microbiology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia
5 Department of Animal Science, College of Coastal Agricultural Sciences, Guangdong Ocean University, Zhanjiang 524088, China
These authors contributed equally to this work.
Antibiotics 2023, 12(3), 543; https://doi.org/10.3390/antibiotics12030543 - 8 Mar 2023
Cited by 34 | Viewed by 6724
Abstract
The Asteraceae family is one of the largest families in the plant kingdom with many of them extensively used for significant traditional and medicinal values. Being a rich source of various phytochemicals, they have found numerous applications in various biological fields and have [...] Read more.
The Asteraceae family is one of the largest families in the plant kingdom with many of them extensively used for significant traditional and medicinal values. Being a rich source of various phytochemicals, they have found numerous applications in various biological fields and have been extensively used for therapeutic purposes. Owing to its potential phytochemicals present and biological activity, these plants have found their way into pharmaceutical industry as well as in various aspects of nanotechnology such as green synthesis of metal oxide nanoparticles. The nanoparticles developed from the plants of Asteraceae family are highly stable, less expensive, non-toxic, and eco-friendly. Synthesized Asteraceae-mediated nanoparticles have extensive applications in antibacterial, antifungal, antioxidant, anticancer, antidiabetic, and photocatalytic degradation activities. This current review provides an opportunity to understand the recent trend to design and develop strategies for advanced nanoparticles through green synthesis. Here, the review discussed about the plant parts, extraction methods, synthesis, solvents utilized, phytochemicals involved optimization conditions, characterization techniques, and toxicity of nanoparticles using species of Asteraceae and their potential applications for human welfare. Constraints and future prospects for green synthesis of nanoparticles from members of the Asteraceae family are summarized. Full article
(This article belongs to the Special Issue Nanoparticles as Antibacterial/Antibiofilm Agents)
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20 pages, 3293 KiB  
Article
Knowledge and Attitudes of Small Animal Veterinarians on Antimicrobial Use Practices Impacting the Selection of Antimicrobial Resistance in Dogs and Cats in Illinois, United States: A Spatial Epidemiological Approach
by Setyo Yudhanto 1 and Csaba Varga 1,2,*
1 Department of Pathobiology, University of Illinois Urbana Champaign, Urbana, IL 61802, USA
2 Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urbana, IL 61802, USA
Antibiotics 2023, 12(3), 542; https://doi.org/10.3390/antibiotics12030542 - 8 Mar 2023
Cited by 8 | Viewed by 3481
Abstract
Inappropriate antimicrobial use in animals and humans has been associated with the emergence of antimicrobial resistance, which has become a global public health concern. Veterinarians’ practice locations and their knowledge and opinions on antimicrobial resistance may influence their antimicrobial prescription practices, which could [...] Read more.
Inappropriate antimicrobial use in animals and humans has been associated with the emergence of antimicrobial resistance, which has become a global public health concern. Veterinarians’ practice locations and their knowledge and opinions on antimicrobial resistance may influence their antimicrobial prescription practices, which could impact the emergence of antimicrobial-resistant bacteria. This study used a spatial modeling approach to identify areas where veterinarians are knowledgeable about factors that impact the selection of antimicrobial resistance. In addition, we sought to identify regions with higher- and lower-than-expected response rates to our survey to aid future antimicrobial stewardship efforts. A total of 83 veterinarians who treated dogs and/or cats across 34 different Illinois counties responded to our online survey. Most of the responders (90.9%) considered that insufficient doses or duration of antibiotic treatments contribute the most to the selection of antimicrobial resistance. A high proportion of veterinarians (78.7%) attended educational programs on antimicrobial use and resistance; however, only 46.2% were knowledgeable about the current antimicrobial resistance profiles of prevalent bacteria in their area. A mean knowledge score for each county was calculated based on the responses of veterinarians to the survey questions. Local Moran’s I statistic was used to identify counties with high and low knowledge scores. A high knowledge score area in the northeast region and a low knowledge score area in the southeast of Illinois were identified. Using scan statistics with a Poisson model that accounted for the estimated number of veterinarians in a county, a higher-than-expected response rate area was identified in central-east Illinois and a lower-than-expected area in the northeast. This study showed the effectiveness of using geographic analysis and spatial statistics to identify locations where future antimicrobial stewardship programs should focus. Full article
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18 pages, 2043 KiB  
Review
Medicinal Plants as Therapeutic Alternatives to Combat Mycobacterium tuberculosis: A Comprehensive Review
by Silvi Gautam 1, Kamal A. Qureshi 2,*, Shabaaz Begum Jameel Pasha 1, Sugapriya Dhanasekaran 3, Ashok Aspatwar 4, Seppo Parkkila 4,5, Samyah Alanazi 6, Akhtar Atiya 7, Mohd Masih Uzzaman Khan 8 and Divya Venugopal 1,*
1 Department of Microbiology, Graphic Era Deemed to be University, Dehradun 248002, India
2 Department of Pharmaceutics, Unaizah College of Pharmacy, Qassim University, Unaizah 51911, Saudi Arabia
3 Department of Molecular Analytics, Institute of Bioinformatics, SSE-SIMATS, Chennai 602105, India
4 Faculty of Medicine and Health Technology, Tampere University, 33520 Tampere, Finland
5 Fimlab Ltd., Tampere University Hospital, 33520 Tampere, Finland
6 Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh 11362, Saudi Arabia
7 Department of Pharmacognosy, College of Pharmacy, King Khalid University (KKU), Guraiger, Abha 62529, Saudi Arabia
8 Department of Pharmaceutical Chemistry and Pharmacognosy, Unaizah College of Pharmacy, Qassim University, Unaizah 51911, Saudi Arabia
Antibiotics 2023, 12(3), 541; https://doi.org/10.3390/antibiotics12030541 - 8 Mar 2023
Cited by 29 | Viewed by 12278
Abstract
Tuberculosis (TB) is a serious infectious disease caused by Mycobacterium tuberculosis (MTB) and a significant health concern worldwide. The main threat to the elimination of TB is the development of resistance by MTB to the currently used antibiotics and more extended treatment methods, [...] Read more.
Tuberculosis (TB) is a serious infectious disease caused by Mycobacterium tuberculosis (MTB) and a significant health concern worldwide. The main threat to the elimination of TB is the development of resistance by MTB to the currently used antibiotics and more extended treatment methods, which is a massive burden on the health care system. As a result, there is an urgent need to identify new, effective therapeutic strategies with fewer adverse effects. The traditional medicines found in South Asia and Africa have a reservoir of medicinal plants and plant-based compounds that are considered another reliable option for human beings to treat various diseases. Abundant research is available for the biotherapeutic potential of naturally occurring compounds in various diseases but has been lagging in the area of TB. Plant-based compounds, or phytoproducts, are being investigated as potential anti-mycobacterial agents by reducing bacterial burden or modulating the immune system, thereby minimizing adverse effects. The efficacy of these phytochemicals has been evaluated through drug delivery using nanoformulations. This review aims to emphasize the value of anti-TB compounds derived from plants and provide a summary of current research on phytochemicals with potential anti-mycobacterial activity against MTB. This article aims to inform readers about the numerous potential herbal treatment options available for combatting TB. Full article
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31 pages, 4929 KiB  
Article
‘Brave Enough’: A Qualitative Study of Veterinary Decisions to Withhold or Delay Antimicrobial Treatment in Pets
by Ri O. Scarborough 1,2,*, Anna E. Sri 1,2, Glenn F. Browning 1,2, Laura Y. Hardefeldt 1,2 and Kirsten E. Bailey 1,2
1 Asia-Pacific Centre for Animal Health, Melbourne Veterinary School, University of Melbourne, Parkville, VIC 3010, Australia
2 National Centre for Antimicrobial Stewardship, Peter Doherty Institute, Parkville, VIC 3052, Australia
Antibiotics 2023, 12(3), 540; https://doi.org/10.3390/antibiotics12030540 - 8 Mar 2023
Cited by 16 | Viewed by 3887
Abstract
Veterinarians sometimes prescribe antimicrobials even when they know or suspect that they are unnecessary. The drivers of this behaviour must be understood to design effective antimicrobial stewardship interventions. Semi-structured interviews were conducted with 22 veterinarians who treated companion animals in Australia. The Theory [...] Read more.
Veterinarians sometimes prescribe antimicrobials even when they know or suspect that they are unnecessary. The drivers of this behaviour must be understood to design effective antimicrobial stewardship interventions. Semi-structured interviews were conducted with 22 veterinarians who treated companion animals in Australia. The Theory of Planned Behaviour was used to organise interview themes, focusing on a decision to withhold antimicrobial therapy in the absence of a clear indication. Many background factors influenced antimicrobial-withholding decisions, including the veterinarian’s communication skills, general attitudes towards antimicrobial resistance (AMR), habits and energy levels. Client awareness of AMR and the veterinarian–client relationship were also important. Beliefs about the consequences of withholding antimicrobials (behavioural beliefs) were dominated by fears of the animal’s condition deteriorating and of failing to meet client expectations. These fears, weighed against the seemingly distant consequences of AMR, were major barriers to withholding antimicrobials. Normative beliefs were primarily focused on the expected approval (or disapproval) of the client and of other veterinarians. Control beliefs about the difficulty of withholding antimicrobials centred around client factors, most importantly, their capacity to adequately monitor their animal, to pay for further investigations, or to undertake non-antimicrobial management, such as wound care, at home. The use of antimicrobials by companion animal veterinarians in the absence of a clear indication is often powerfully driven by behavioural beliefs, chiefly, fears of clinical deterioration and of failing to meet client expectations. Full article
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