Characterisation and transferability of antibiotic resistance genes from lactic acid bacteria isolated from Irish pork and beef abattoirs

The spread of resistance to antibiotics is a major health concern worldwide due to the increasing rate of isolation of multidrug resistant pathogens hampering the treatment of infections. The food chain has been recognized as one of the key routes of antibiotic resistant bacteria transmission between animals and humans. Considering that lactic acid bacteria (LAB) could act as a reservoir of transferable antibiotic resistance genes, LAB strains intended to be used as feed additives should be monitored for their safety. Sixty-five LAB strains which might be potentially used as probiotic feed additives or silage inoculants, were assessed for susceptibility to eight clinically relevant antimicrobials by a minimum inhibitory concentration determination. Among antimicrobial resistant strains, a prevalence of selected genes associated with the acquired resistance was investigated. Nineteen LAB strains displayed phenotypic resistance to one antibiotic, and 15 strains were resistant to more than one of the tested antibiotics. The resistance to aminoglycosides and tetracyclines were the most prevalent and were found in 37 and 26% of the studied strains, respectively. Phenotypic resistance to other antimicrobials was found in single strains. Determinants related to resistance phenotypes were detected in 15 strains as follows, the aph(3″)-IIIa gene in 9 strains, the lnu(A) gene in three strains, the str(A)-str(B), erm(B), msr(C), and tet(M) genes in two strains and the tet(K) gene in one strain. The nucleotide sequences of the detected genes revealed homology to the sequences of the transmissible resistance genes found in lactic acid bacteria as well as pathogenic bacteria. Our study highlights that LAB may be a reservoir of antimicrobial resistance determinants, thus, the first and key step in considering the usefulness of LAB strains as feed additives should be an assessment of their antibiotic resistance. This safety criterion should always precede more complex studies, such as an assessment of adaptability of a strain or its beneficial effect on a host. These results would help in the selection of the best LAB strains for use as feed additives. Importantly, presented data can be useful for revising the current microbiological cut-off values within the genus Lactobacillus and Pediococcus.

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Characterization of bacteria and antibiotic resistance in commercially-produced cheeses sold in China

Journal of Food Protection ◽

10.4315/jfp-21-198 ◽

2021 ◽

Author(s):

Jinghui Yao ◽

Jing Gao ◽

Jianming Guo ◽

Hengan Wang ◽

En Zhang ◽

...

Keyword(s):

Antibiotic Resistance ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Acquired Resistance ◽

Antibiotic Resistance Genes ◽

16S Rrna Gene Sequencing ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Rrna Gene ◽

Rrna Gene Sequencing

The consumption of cheese in China is increasing rapidly. Little is known about the microbiota, the presence of antibiotic-resistant bacteria, or the distribution of antibiotic resistance genes (ARGs) in commercially-produced cheeses sold in China. These are important criteria for evaluating quality and safety. Thus, this study assessed the metagenomics of fifteen types of cheese using 16S rRNA gene sequencing. Fourteen bacterial genera were detected. Lactococcus , Lactobacillus , and Streptococcus were dominant based on numbers of sequence reads. Multidrug-resistant lactic acid bacteria were isolated from most of the types of cheese. The isolates showed 100% and 91.7% resistance to streptomycin and sulfamethoxazole, respectively, and genes involved in acquired resistance to streptomycin ( strB) and sulfonamides ( sul2) were detected with high frequency. To analyze the distribution of ARGs in the cheeses in overall, 309 ARGs from eight categories of ARG and nine transposase genes were profiled. A total of 169 ARGs were detected in the 15 cheeses; their occurrence and abundance varied significantly between cheeses. Our study demonstrates that there is various diversity of the bacteria and ARGs in cheeses sold in China. The risks associated with multidrug resistance of dominant lactic acid bacteria are of great concern.

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Production of Optically Pure d-Lactic Acid in Mineral Salts Medium by Metabolically Engineered Escherichia coli W3110

Applied and Environmental Microbiology ◽

10.1128/aem.69.1.399-407.2003 ◽

2003 ◽

Vol 69 (1) ◽

pp. 399-407 ◽

Cited By ~ 166

Author(s):

Shengde Zhou ◽

T. B. Causey ◽

A. Hasona ◽

K. T. Shanmugam ◽

L. O. Ingram

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Lactic Acid ◽

Resistance Genes ◽

Initial Period ◽

Maximum Yield ◽

Optical Purity ◽

Antibiotic Resistance Genes ◽

High Yield ◽

Mineral Salts

ABSTRACT The resistance of polylactide to biodegradation and the physical properties of this polymer can be controlled by adjusting the ratio of l-lactic acid to d-lactic acid. Although the largest demand is for the l enantiomer, substantial amounts of both enantiomers are required for bioplastics. We constructed derivatives of Escherichia coli W3110 (prototrophic) as new biocatalysts for the production of d-lactic acid. These strains (SZ40, SZ58, and SZ63) require only mineral salts as nutrients and lack all plasmids and antibiotic resistance genes used during construction. d-Lactic acid production by these new strains approached the theoretical maximum yield of two molecules per glucose molecule. The chemical purity of this d-lactic acid was ∼98% with respect to soluble organic compounds. The optical purity exceeded 99%. Competing pathways were eliminated by chromosomal inactivation of genes encoding fumarate reductase (frdABCD), alcohol/aldehyde dehydrogenase (adhE), and pyruvate formate lyase (pflB). The cell yield and lactate productivity were increased by a further mutation in the acetate kinase gene (ackA). Similar improvements could be achieved by addition of 10 mM acetate or by an initial period of aeration. All three approaches reduced the time required to complete the fermentation of 5% glucose. The use of mineral salts medium, the lack of antibiotic resistance genes or plasmids, the high yield of d-lactate, and the high product purity should reduce costs associated with nutrients, purification, containment, biological oxygen demand, and waste treatment.

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Role of Lactic Acid Bacteria from Animal Products in Human Health – One Health Perspective

10.20944/preprints202108.0174.v1 ◽

2021 ◽

Author(s):

Carla Miranda ◽

Diogo Contente ◽

Gilberto Igrejas ◽

Sandra Paula de Aguiar e Câmara ◽

Maria de Lurdes Enes Dapkevicius ◽

...

Keyword(s):

Antibiotic Resistance ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Foodborne Pathogens ◽

Food Chain ◽

Antimicrobial Properties ◽

Antibiotic Resistance Genes ◽

Health Impact ◽

Animal Products ◽

Beneficial Effects

Animal products, in particular dairy and fermented products, are natural, major sources of lactic acid bacteria (LAB). Due to their antimicrobial properties, LAB are used in humans and in animals, with beneficial effects, as probiotics or in the treatment of a variety of diseases. In livestock production, LAB contribute to animal performance, health, and productivity. In the food industry, LAB are applied as bioprotective and biopreservation agents, contributing to improve food safety and quality. However, some studies have described resistance to relevant antibiotics in LAB, with the concomitant risks associated to the transfer of antibiotic resistance genes to foodborne pathogens, their potential dissemination throughout the food chain, and the environment. Here, we summarize the application of LAB in livestock and animal products, as well as the health impact of LAB in animal food products. In general, the beneficial effects of LAB on the human food chain seem to outweigh the potential risks associated with their consumption as part of animal and human diets. However, further studies and continuous monitorization efforts are needed to ensure their safe application in animal products and in the control of pathogenic microorganisms, preventing the possible risks associated with antibiotic resistance and, thus, protecting public health.

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Role of Exposure to Lactic Acid Bacteria from Foods of Animal Origin in Human Health

Foods ◽

10.3390/foods10092092 ◽

2021 ◽

Vol 10 (9) ◽

pp. 2092

Author(s):

Carla Miranda ◽

Diogo Contente ◽

Gilberto Igrejas ◽

Sandra P. A. Câmara ◽

Maria de Lurdes Enes Dapkevicius ◽

...

Keyword(s):

Antibiotic Resistance ◽

Lactic Acid ◽

Lactic Acid Bacteria ◽

Food Chain ◽

Antimicrobial Properties ◽

Antibiotic Resistance Genes ◽

Nutrient Digestibility ◽

Animal Origin ◽

Animal Products ◽

Beneficial Effects

Animal products, in particular dairy and fermented products, are major natural sources of lactic acid bacteria (LAB). These are known for their antimicrobial properties, as well as for their roles in organoleptic changes, antioxidant activity, nutrient digestibility, the release of peptides and polysaccharides, amino acid decarboxylation, and biogenic amine production and degradation. Due to their antimicrobial properties, LAB are used in humans and in animals, with beneficial effects, as probiotics or in the treatment of a variety of diseases. In livestock production, LAB contribute to animal performance, health, and productivity. In the food industry, LAB are applied as bioprotective and biopreservation agents, contributing to improve food safety and quality. However, some studies have described resistance to relevant antibiotics in LAB, with the concomitant risks associated with the transfer of antibiotic resistance genes to foodborne pathogens and their potential dissemination throughout the food chain and the environment. Here, we summarize the application of LAB in livestock and animal products, as well as the health impact of LAB in animal food products. In general, the beneficial effects of LAB on the human food chain seem to outweigh the potential risks associated with their consumption as part of animal and human diets. However, further studies and continuous monitorization efforts are needed to ensure their safe application in animal products and in the control of pathogenic microorganisms, preventing the possible risks associated with antibiotic resistance and, thus, protecting public health.

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Association of nanoparticles with extracellular genetic material and implications for the fate of antibiotic resistance genes in environmental systems

10.1021/scimeetings.0c07368 ◽

2020 ◽

Author(s):

Nadrat Chowdhury

Keyword(s):

Antibiotic Resistance ◽

Resistance Genes ◽

Genetic Material ◽

Antibiotic Resistance Genes ◽

Environmental Systems

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Quintuplex PCR to Detect Antibiotic Resistance Genes in Streptococcus pneumoniae

Journal of Clinical and Health Sciences ◽

10.24191/jchs.v2i1.5861 ◽

2016 ◽

Vol 1 (2) ◽

pp. 22 ◽

Cited By ~ 2

Author(s):

Navindra Kumari Palanisamy ◽

Parasakthi Navaratnam ◽

Shamala Devi Sekaran

Keyword(s):

Antibiotic Resistance ◽

Streptococcus Pneumoniae ◽

Resistance Genes ◽

Bacterial Pathogen ◽

Antibiotic Resistance Genes ◽

Pcr Amplification ◽

Penicillin Resistance ◽

Penicillin Binding Proteins ◽

Efflux Mechanism ◽

Mic Value

Introduction: Streptococcus pneumoniae is an important bacterial pathogen, causing respiratory infection. Penicillin resistance in S. pneumoniae is associated with alterations in the penicillin binding proteins, while resistance to macrolides is conferred either by the modification of the ribosomal target site or efflux mechanism. This study aimed to characterize S. pneumoniae and its antibiotic resistance genes using 2 sets of multiplex PCRs. Methods: A quintuplex and triplex PCR was used to characterize the pbp1A, ermB, gyrA, ply, and the mefE genes. Fifty-eight penicillin sensitive strains (PSSP), 36 penicillin intermediate strains (PISP) and 26 penicillin resistance strains (PRSP) were used. Results: Alteration in pbp1A was only observed in PISP and PRSP strains, while PCR amplification of the ermB or mefE was observed only in strains with reduced susceptibility to erythromycin. The assay was found to be sensitive as simulated blood cultures showed the lowest level of detection to be 10cfu. Conclusions: As predicted, the assay was able to differentiate penicillin susceptible from the non-susceptible strains based on the detection of the pbp1A gene, which correlated with the MIC value of the strains.

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