Safety Evaluation of Oral Care Probiotics Weissella cibaria CMU and CMS1 by Phenotypic and Genotypic Analysis

Weissella cibaria CMU and CMS1 are known to exert beneficial effects on the oral cavity but have not yet been determined to be generally recognized as safe (GRAS), although they are used as commercial strains in Korea. We aimed to verify the safety of W. cibaria CMU and CMS1 strains through phenotypic and genotypic analyses. Their safety was evaluated by a minimum inhibitory concentration assay for 14 antibiotics, DNA analysis for 28 antibiotic resistance genes (ARGs) and one conjugative element, antibiotic resistance gene transferability, virulence gene analysis, hemolysis, mucin degradation, toxic metabolite production, and platelet aggregation reaction. W. cibaria CMU showed higher kanamycin resistance than the European Food Safety Authority (EFSA) cut-off, but this resistance was not transferred to the recipient strain. W. cibaria CMU and CMS1 lacked ARGs in chromosomes and plasmids, and genetic analysis confirmed that antibiotic resistance of kanamycin was an intrinsic characteristic of W. cibaria. Additionally, these strains did not harbor virulence genes associated with pathogenic bacteria and lacked toxic metabolite production, β-hemolysis, mucin degradation, bile salt deconjugation, β-glucuronidase, nitroreductase activity, gelatin liquefaction, phenylalanine degradation, and platelet aggregation. Our findings demonstrate that W. cibaria CMU and CMS1 can achieve the GRAS status in future.

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Safety Evaluation of Weissella cibaria JW15 by Phenotypic and Genotypic Property Analysis

Microorganisms ◽

10.3390/microorganisms9122450 ◽

2021 ◽

Vol 9 (12) ◽

pp. 2450

Author(s):

Ye-Ji Jang ◽

Hee-Min Gwon ◽

Woo-Soo Jeong ◽

Soo-Hwan Yeo ◽

So-Young Kim

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Virulence Genes ◽

Antioxidant Activities ◽

Antibiotic Resistance Genes ◽

International Standards ◽

Toxic Metabolite ◽

Food Ingredient ◽

Weissella Cibaria ◽

Genotypic Analysis

Weissella cibaria is one of the bacteria in charge of the initial fermentation of kimchi and has beneficial effects such as immune-modulating, antagonistic, and antioxidant activities. In our study, we aimed to estimate the safety of W. cibaria JW15 for the use of probiotics according to international standards based on phenotypic (antibiotic resistance, hemolysis, and toxic metabolite production) and genotypic analysis (virulence genes including antibiotic resistance genes). The results of the safety assessment on W. cibaria JW15 were as follows; (1) antibiotic resistance genes (ARGs) (kanamycin and vancomycin etc.) were intrinsic characteristics; (2) There were no acquired virulence genes including Cytolysin (cylA), aggregation substance (asa1), Hyaluronidase (hyl), and Gelatinase (gelE); (3) this strain also lacked β-hemolysis and the production of toxic metabolites (D-lactate and bile salt deconjugation). Consequently, W. cibaria JW15 is expected to be applied as a functional food ingredient in the food market.

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Longitudinal assessment of antibiotic resistance gene profiles in gut microbiomes of infants at risk of eczema

10.21203/rs.2.18486/v2 ◽

2020 ◽

Author(s):

Evelyn Loo ◽

Amanda Zain ◽

Gaik Chin Yap ◽

Rikky W Purbojati ◽

Daniela I Drautz-Moses ◽

...

Keyword(s):

Antibiotic Resistance ◽

Cohort Study ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

First Year ◽

Beta Lactam ◽

First Year Of Life

Abstract Background While there is increasing knowledge about the gut microbiome, the factors influencing and the significance of the gut resistome are still not well understood. Infant gut commensals risk transferring multidrug-resistant antibiotic resistance genes (ARGs) to pathogenic bacteria. The rapid spread of multidrug-resistant pathogenic bacteria is a worldwide public health concern. Better understanding the naïve infant gut resistome may build the evidence base for antimicrobial stewardship in both humans and in the food industry. Given the high carriage rate of extended spectrum beta-lactamase (ESBL)- producing Enterobacteriaceae in Asia, we aimed to evaluate community prevalence, dynamics, and longitudinal changes in antibiotic resistance gene (ARG) profiles and prevalence of ESBL-producing .E coli and K. pneumoniae in the intestinal microbiome of infants participating in the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) study, a longitudinal cohort study of pregnant women and their infants. Methods We analysed ARGs in the first year of life among 75 infants who had stool samples collected at multiple timepoints using metagenomics. Results The mean number of ARGs per infant increased with age. The most common ARGs identified confer resistance to aminoglycoside, beta-lactam, macrolide and tetracycline antibiotics; all infants harboured these antibiotic resistance genes at some point in the first year of life. Few ARGs persisted throughout the first year of life. Beta-lactam resistant Escherichia coli and Klebsiella pneumoniae were detected in 4 (5.3%) and 32 (42.7%) of subjects respectively. Conclusion In this longitudinal cohort study of infants living in a region with high endemic antibacterial resistance, we demonstrate that the majority of the infants harboured several antibiotic resistance genes in their gut and showed that the infant gut resistome is diverse and dynamic over the first year of life.

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Longitudinal assessment of antibiotic resistance gene profiles in gut microbiomes of infants at risk of eczema

10.21203/rs.2.18486/v3 ◽

2020 ◽

Author(s):

Evelyn Loo(Former Corresponding Author) ◽

Amanda Zain ◽

Gaik Chin Yap ◽

Rikky W Purbojati ◽

Daniela I Drautz-Moses ◽

...

Keyword(s):

Antibiotic Resistance ◽

Cohort Study ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Multidrug Resistant ◽

First Year ◽

Beta Lactam ◽

First Year Of Life

Abstract Background While there is increasing knowledge about the gut microbiome, the factors influencing and the significance of the gut resistome are still not well understood. Infant gut commensals risk transferring multidrug-resistant antibiotic resistance genes (ARGs) to pathogenic bacteria. The rapid spread of multidrug-resistant pathogenic bacteria is a worldwide public health concern. Better understanding the naïve infant gut resistome may build the evidence base for antimicrobial stewardship in both humans and in the food industry. Given the high carriage rate of extended spectrum beta-lactamase (ESBL)- producing Enterobacteriaceae in Asia, we aimed to evaluate community prevalence, dynamics, and longitudinal changes in antibiotic resistance gene (ARG) profiles and prevalence of ESBL-producing E. coli and K. pneumoniae in the intestinal microbiome of infants participating in the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) study, a longitudinal cohort study of pregnant women and their infants. Methods: We analysed ARGs in the first year of life among 75 infants at risk of eczema who had stool samples collected at multiple timepoints using metagenomics. Results: The mean number of ARGs per infant increased with age. The most common ARGs identified confer resistance to aminoglycoside, beta-lactam, macrolide and tetracycline antibiotics; all infants harboured these antibiotic resistance genes at some point in the first year of life. Few ARGs persisted throughout the first year of life. Beta-lactam resistant Escherichia coli and Klebsiella pneumoniae were detected in 4 (5.3%) and 32 (42.7%) of subjects respectively. Conclusion: In this longitudinal cohort study of infants living in a region with high endemic antibacterial resistance, we demonstrate that majority of the infants harboured several antibiotic resistance genes in their gut and showed that the infant gut resistome is diverse and dynamic over the first year of life.

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Identification and characterization of colistin-resistant E. coli and K. pneumoniae isolated from Lower Himalayan Region of India

SN Applied Sciences ◽

10.1007/s42452-021-04596-3 ◽

2021 ◽

Vol 3 (6) ◽

Author(s):

Avinash Singh ◽

Anand Kumar Keshri ◽

Suraj Singh Rawat ◽

Deepak Swami ◽

Kala Venkata Uday ◽

...

Keyword(s):

Antibiotic Resistance ◽

Pathogenic Bacteria ◽

Health Workers ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Phenotypic Characterization ◽

Lag Phase ◽

Bacterial Strains ◽

E Coli

AbstractMultidrug resistance is one of the worldwide public health concerns. Water represents the most suitable environment, for the exchange of antibiotic resistance genes among pathogenic to non-pathogenic bacteria. Therefore, we aimed to screen the presence of blaNDM-1, blaTEM, blaSHV, blaCTX-M and mcr1–5 genes among water samples from different locations of Lower Himachal Pradesh. We examined the genotypic incidences of blaNDM-1, blaTEM, blaSHV, blaCTXM and mcr1–5 by polymerase chain reaction. Survivability assay, fitness cost assay and biofilm assay were performed for phenotypic characterization. The presence of blaNDM-1 and its related variants were analysed and confirmed by sequencing-based approaches. A total of 73 bacterial strains were identified on M-lauryl sulphate agar medium. Out of 73 colistin-resistant isolates, 34 were E. coli and 39 were K. pneumoniae. Out of 34 samples, 2 (5.8%), 2 (5.8%), 5 (14.7%), 5 (14.7%) and 4 (11.76%) E. coli were blaTEM, blaSHV,blaCTXM-1, blaCTXM-2 and blaCTXM-15 positive, respectively. Among 39 K. pneumoniae, 15 (38.4%), 6 (15.3%), 10 (25.6%), 9 (23.07%) and 10 (25.6%) were blaTEM, blaSHV, blaCTXM-1, blaCTXM-2 and blaCTXM-15 positive, respectively. Interestingly, we observed one E. coli (HG4) isolate with both blaNDM-1 and mcr-1 gene. Further analysis showed HG4 isolate has lesser survivability on the cotton swab, long lag phase and less biofilm production compared to colistin-sensitive isolates. Detection of E. coli with blaNDM-1 and mcr-1 in this geographical region is an alarming signal for tourists, community, health workers and policymakers. Hence, it is utmost important to take appropriate measures to control the dissemination of antibiotic resistance gene in such pristine locations.

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Metagenomics Analysis Reveals the Microbial Communities, Antimicrobial Resistance Gene Diversity and Potential Pathogen Transmission Risk of Two Different Landfills in China

Diversity ◽

10.3390/d13060230 ◽

2021 ◽

Vol 13 (6) ◽

pp. 230

Author(s):

Shan Wan ◽

Min Xia ◽

Jie Tao ◽

Yanjun Pang ◽

Fugen Yu ◽

...

Keyword(s):

Antibiotic Resistance ◽

Microbial Communities ◽

Resistance Gene ◽

Resistance Genes ◽

Gene Diversity ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Pathogen Transmission ◽

Transmission Risk ◽

Antimicrobial Resistance Gene

In this study, we used a metagenomic approach to analyze microbial communities, antibiotic resistance gene diversity, and human pathogenic bacterium composition in two typical landfills in China. Results showed that the phyla Proteobacteria, Bacteroidetes, and Actinobacteria were predominant in the two landfills, and archaea and fungi were also detected. The genera Methanoculleus, Lysobacter, and Pseudomonas were predominantly present in all samples. sul2, sul1, tetX, and adeF were the four most abundant antibiotic resistance genes. Sixty-nine bacterial pathogens were identified from the two landfills, with Klebsiella pneumoniae, Bordetella pertussis, Pseudomonas aeruginosa, and Bacillus cereus as the major pathogenic microorganisms, indicating the existence of potential environmental risk in landfills. In addition, KEGG pathway analysis indicated the presence of antibiotic resistance genes typically associated with human antibiotic resistance bacterial strains. These results provide insights into the risk of pathogens in landfills, which is important for controlling the potential secondary transmission of pathogens and reducing workers’ health risk during landfill excavation.

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Nitric oxide (NO) elicits aminoglycoside tolerance in Escherichia coli but antibiotic resistance gene carriage and NO sensitivity have not co-evolved

Archives of Microbiology ◽

10.1007/s00203-021-02245-2 ◽

2021 ◽

Author(s):

Cláudia A. Ribeiro ◽

Luke A. Rahman ◽

Louis G. Holmes ◽

Ayrianna M. Woody ◽

Calum M. Webster ◽

...

Keyword(s):

Nitric Oxide ◽

Antibiotic Resistance ◽

Antibiotic Susceptibility ◽

Bacterial Pathogens ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Resistance Mechanisms ◽

Current Work ◽

E Coli ◽

Respiratory Inhibitor

AbstractThe spread of multidrug-resistance in Gram-negative bacterial pathogens presents a major clinical challenge, and new approaches are required to combat these organisms. Nitric oxide (NO) is a well-known antimicrobial that is produced by the immune system in response to infection, and numerous studies have demonstrated that NO is a respiratory inhibitor with both bacteriostatic and bactericidal properties. However, given that loss of aerobic respiratory complexes is known to diminish antibiotic efficacy, it was hypothesised that the potent respiratory inhibitor NO would elicit similar effects. Indeed, the current work demonstrates that pre-exposure to NO-releasers elicits a > tenfold increase in IC50 for gentamicin against pathogenic E. coli (i.e. a huge decrease in lethality). It was therefore hypothesised that hyper-sensitivity to NO may have arisen in bacterial pathogens and that this trait could promote the acquisition of antibiotic-resistance mechanisms through enabling cells to persist in the presence of toxic levels of antibiotic. To test this hypothesis, genomics and microbiological approaches were used to screen a collection of E. coli clinical isolates for antibiotic susceptibility and NO tolerance, although the data did not support a correlation between increased carriage of antibiotic resistance genes and NO tolerance. However, the current work has important implications for how antibiotic susceptibility might be measured in future (i.e. ± NO) and underlines the evolutionary advantage for bacterial pathogens to maintain tolerance to toxic levels of NO.

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COVID-19 Lockdowns May Reduce Resistance Genes Diversity in the Human Microbiome and the Need for Antibiotics

International Journal of Molecular Sciences ◽

10.3390/ijms22136891 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6891

Author(s):

João S. Rebelo ◽

Célia P. F. Domingues ◽

Francisco Dionisio ◽

Manuel C. Gomes ◽

Ana Botelho ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Bacterial Resistance ◽

Human Microbiome ◽

Antibiotic Resistance Genes ◽

Public Health Problem ◽

Small World ◽

Physical Contact ◽

Hygiene Measures

Recently, much attention has been paid to the COVID-19 pandemic. Yet bacterial resistance to antibiotics remains a serious and unresolved public health problem that kills hundreds of thousands of people annually, being an insidious and silent pandemic. To contain the spreading of the SARS-CoV-2 virus, populations confined and tightened hygiene measures. We performed this study with computer simulations and by using mobility data of mobile phones from Google in the region of Lisbon, Portugal, comprising 3.7 million people during two different lockdown periods, scenarios of 40 and 60% mobility reduction. In the simulations, we assumed that the network of physical contact between people is that of a small world and computed the antibiotic resistance in human microbiomes after 180 days in the simulation. Our simulations show that reducing human contacts drives a reduction in the diversity of antibiotic resistance genes in human microbiomes. Kruskal–Wallis and Dunn’s pairwise tests show very strong evidence (p < 0.000, adjusted using the Bonferroni correction) of a difference between the four confinement regimes. The proportion of variability in the ranked dependent variable accounted for by the confinement variable was η2 = 0.148, indicating a large effect of confinement on the diversity of antibiotic resistance. We have shown that confinement and hygienic measures, in addition to reducing the spread of pathogenic bacteria in a human network, also reduce resistance and the need to use antibiotics.

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Antimicrobial Resistance and CRISPR Typing Among Salmonella Isolates From Poultry Farms in China

Frontiers in Microbiology ◽

10.3389/fmicb.2021.730046 ◽

2021 ◽

Vol 12 ◽

Author(s):

Cui Li ◽

Yulong Wang ◽

Yufeng Gao ◽

Chao Li ◽

Boheng Ma ◽

...

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Antibiotic Resistance Gene ◽

Antibiotic Resistance Genes ◽

Direct Repeat ◽

Epidemiological Data ◽

Multidrug Resistant ◽

Typing Method ◽

Crispr Locus ◽

Research Areas

Although knowledge of the clustered regularly interspaced short palindromic repeat (CRISPR)-Cas system has been applied in many research areas, comprehensive studies of this system in Salmonella, particularly in analysis of antibiotic resistance, have not been reported. In this work, 75 Salmonella isolates obtained from broilers or broilers products were characterized to determine their antimicrobial susceptibilities, antibiotic resistance gene profiles, and CRISPR array diversities, and genotyping was explored. In total, 80.00% (60/75) of the strains were multidrug resistant, and the main pattern observed in the isolates was CN-AZM-AMP-AMC-CAZ-CIP-ATM-TE-SXT-FOS-C. The resistance genes of streptomycin (aadA), phenicol (floR-like and catB3-like), β-lactams (blaTEM, blaOXA, and blaCTX), tetracycline [tet(A)-like], and sulfonamides (sul1 and sul2) appeared at higher frequencies among the corresponding resistant isolates. Subsequently, we analyzed the CRISPR arrays and found 517 unique spacer sequences and 31 unique direct repeat sequences. Based on the CRISPR spacer sequences, we developed a novel typing method, CRISPR locus three spacer sequences typing (CLTSST), to help identify sources of Salmonella outbreaks especially correlated with epidemiological data. Compared with multi-locus sequence typing (MLST), conventional CRISPR typing (CCT), and CRISPR locus spacer pair typing (CLSPT), discrimination using CLTSST was weaker than that using CCT but stronger than that using MLST and CLSPT. In addition, we also found that there were no close correlations between CRISPR loci and antibiotics but had close correlations between CRISPR loci and antibiotic resistance genes in Salmonella isolates.

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Monitoring and Evaluation of Antibiotic Resistance Genes in Three Rivers in Northeast China

10.21203/rs.3.rs-313046/v2 ◽

2021 ◽

Author(s):

Chen Zhao ◽

Chenyu Li ◽

Xiaoming Wang ◽

Zhuosong Cao ◽

Chao Gao ◽

...

Keyword(s):

Antibiotic Resistance ◽

River Water ◽

Resistance Genes ◽

Northeast China ◽

Pathogenic Bacteria ◽

Respiratory Infections ◽

Antibiotic Resistance Genes ◽

Distribution Characteristics ◽

Beta Lactam ◽

Three Rivers

Abstract Background: Antibiotic resistance genes (ARGs) have become an important public health problem. In this study, we used metagenomic sequencing to analyze the composition of ARGs in certain original habitats of northeast China, comprising three different rivers and riverbank soils of the Heilongjiang River, Tumen River, and Yalu River. Results: Twenty types of ARG were detected in every water sample. The major ARGs were multidrug resistance genes, at approximately 0.5 copies/16s rRNA, accounting for 57.5% of the total ARG abundance. The abundance of multidrug, bacitracin, beta-lactam, macrolide‑lincosamide‑streptogramin, sulfonamide, fosmidomycin, and polymyxin resistance genes covered 96.9% of the total ARG abundance. No significant ecological boundary of ARG diversity was observed. The compositions of the resistance genes in the three rivers were very similar to each other, and 92.1% of ARG subtypes were shared by all water samples. Except for vancomycin resistance genes, almost all ARGs in riverbank soils were detected in the river water. About 31.05% ARGs were carried by Pseudomonas. Opportunistic pathogenic bacteria carrying resistance genes were mainly related to diarrhea and respiratory infections. Multidrug and beta-lactam resistance genes correlated positively with mobile genetic elements (MGEs), indicating a potential risk of diffusion.Conclusions: The composition of ARGs in three different rivers was similar, indicating that climate played an important role in ARG occurrence. ARG subtypes in river water were almost completely the same as those in riverbank soil. ARGs had no significant geographical distribution characteristics. Many ARGs were carried by human pathogenic bacteria related to human diarrhea and respiratory infections, such as Pseudomonas aeruginosa and Aeromonas caviae. In general, our results provide a valuable dataset of river water ARG distribution in northeast China. The related ecological geography distribution characteristics should be further explored.

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Genome Assessment of Antibiotic Resistance Genes in Probiotic Bacteria and a Literature Review

10.21203/rs.3.rs-254514/v1 ◽

2021 ◽

Author(s):

Mehdi Fatahi-Bafghi ◽

Sara Naseri ◽

Ali Alizehi

Keyword(s):

Antibiotic Resistance ◽

Genome Sequence ◽

Resistance Genes ◽

Pathogenic Bacteria ◽

Antibiotic Resistance Genes ◽

Probiotic Bacteria ◽

Whole Genome Sequence ◽

Probiotic Properties ◽

Antibiotic Resistant ◽

To Come

Abstract Having various clinical applications, probiotic bacteria are currently used in the diet. There are reports of antibiotic resistance genes (ARGs) in these bacteria that can be transferred to other microflora and pathogenic bacteria. The aim of the study is to examine whole-genome sequence analysis in bacteria with probiotic properties. Moreover, this study follows existing issues about the importance and presence of ARGs in these bacteria the dangers of which may affect human health in the years to come. In the present study, 126 complete probiotic bacterial genomes were collected and analysed for ARGs. The results of the study shows there are various antibiotic resistant genes of in these bacteria some of which can be transmitted to other bacteria. We propose microorganisms be applied as a probiotic element in various types of products, antibiogram be conducted for a large number of antibiotics and analysis of complete genome sequence for ARGs prediction.

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