scholarly journals Antimicrobial Susceptibility of Lactic Acid Bacteria Strains of Potential Use as Feed Additives - The Basic Safety and Usefulness Criterion

2021 ◽  
Vol 8 ◽  
Author(s):  
Ilona Stefańska ◽  
Ewelina Kwiecień ◽  
Katarzyna Jóźwiak-Piasecka ◽  
Monika Garbowska ◽  
Marian Binek ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Resistance Genes ◽  
Pathogenic Bacteria ◽  
Feed Additives ◽  
Health Concern ◽  
Resistant Bacteria ◽  
Safety Criterion ◽  
Phenotypic Resistance

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.

scholarly journals Prevalence And Characterization Of Plasmid-Mediated Quinolone Resistance In Various Aquatic Sources

2021 ◽  
Author(s):  
Farhan Yusuf ◽  
Kimberley Gilbride
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Antibiotic Resistance Genes ◽  
Quinolone Resistance ◽  
Resistant Bacteria ◽  
Rrna Gene ◽  
Environmental Isolates ◽  
Topoisomerase Iv ◽  
Phenotypic Resistance ◽  
Ciprofloxacin Resistance

Bacterial isolates found in aquatic ecosystems often carry antibiotic resistance genes (ARGs). These ARGs are often found on plasmids and transposons, which allows them to be proliferate throughout bacterial communities via horizontal gene transfer (HGT) causing dissemination of multidrug resistance. The increase in antibiotic resistance has raised concerns about the ability to continue to use these drugs to fight infectious diseases. Novel synthetic antibiotics like ciprofloxacin that are not naturally found in the environment were developed to prevent resistances. However, ciprofloxacin resistance has occurred through chromosomal gene mutations of type 2 topoisomerases or by the acquisition of plasmid-mediated quinolone resistances (PMQR). A particular PMQR, qnr genes, encoding for pentapeptide repeat proteins that confer low levels of quinolone resistance and protect DNA gyrase and topoisomerase IV from antibacterial activity. These qnr genes have been identified globally in both clinical and environmental isolates. The aim of this study was to determine the prevalence of ciprofloxacin-resistant bacteria in aquatic environments in the Greater Toronto Area and the potential dissemination of ciprofloxacin resistance. With the selective pressure of ciprofloxacin, we hypothesize that ciprofloxacin-resistant bacteria (CipR) in the environment may carry PMQR mechanisms while the sensitive population (CipS) would not carry PMQR genes. Isolates were tested for resistance to an additional 12 different antibiotics and identified using Sanger sequencing PCR products of the 16S rRNA gene. To determine which genes are responsible for ciprofloxacin resistance, multiplex PCR of associated qnr genes, qnrA, qnrB, and qnrS, was carried out on 202 environmental isolates. Our data demonstrate a similar prevalence of qnr genes was found in CipR (19%) and CipS (14%) populations suggesting that the presence of these genes was not necessarily correlated with the phenotypic resistance to the antibiotic. Furthermore, ciprofloxacinresistant bacteria were found in all locations at similar frequencies suggesting that resistance genes are widespread and could possibly arise through HGT events. Overall, determining the underlying cause and prevalence of ciprofloxacin resistance could help re-establish the effectiveness of these antimicrobial compounds.

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

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.

Metagenomic analysis of effects of oxytetracycline and copper on antibiotic resistance genes and associated pathogenic hosts in swine manure compost

2020 ◽  
Author(s):  
Honghong Guo ◽  
jie gu ◽  
Xiaojuan Wang ◽  
Zilin Song ◽  
Xun Qian ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Pathogenic Bacteria ◽  
Swine Manure ◽  
Antibiotic Resistance Genes ◽  
Feed Additives ◽  
Poultry Feed ◽  
Risk Scores ◽  
Composting Process ◽  
Positive Effects

Abstract Background: The proliferation of antibiotic resistance genes (ARGs) in compost and their horizontal transfer to human pathogenic bacteria (HPB) may lead to the failure of human antibiotics. However, the antibiotic resistome in compost has not been comprehensively characterized. This study used a metagenomic approach to obtain new insights into the effects of oxytetracycline (OTC) and copper (Cu) on the antibiotic resistome during swine manure composting and the risks posed to human health. Results: The results showed that composting reduced the abundances and diversity of ARGs and HPB in swine manure. In total, 289 ARG subtypes and 19 ARG types were detected in the samples with abundances ranging from 1.08 ´ 10 –1 to 9.39 ´ 10 –1 copies/16S rRNA, which mainly encoded tetracycline, aminoglycoside, and macrolide–lincosamide–streptogramin (MLS) resistance genes. The application of OTC and Cu, especially the combined application, exacerbated the compost resistome risk scores and specific ARG subtypes responded differently. Tetracycline, multidrug, and MLS resistance genes mainly affected resistance profiles of HPB throughout the composting process. HPB and intI1 had significant positive effects on determining the ARG profiles during the composting process, and the co-selective effect of heavy metals may increase the abundances of ARGs via strong positive effects on intI1 . In addition, the effect of mobile genetic elements on the horizontal gene transfer of ARGs should not be ignored. Conclusions: This study of the antibiotic resistome in compost indicates the need for effective regulation of the misuse of livestock and poultry feed additives in order to minimize the spread of the antibiotic resistome in agro-ecosystems and decrease the potential risk to public health. Keywords: Antibiotic resistome; Composting; Metagenome; Pathogenic host; Swine manure

scholarly journals Occurrence of Bacterial Markers and Antibiotic Resistance Genes in Sub-Saharan Rivers Receiving Animal Farm Wastewaters

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Dhafer Mohammed M. Al Salah ◽  
Amandine Laffite ◽  
John Poté
Keyword(s):  
Developing Countries ◽  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Bacterial Load ◽  
Antibiotic Resistance Genes ◽  
Health Concern ◽  
Resistant Bacteria ◽  
P Value ◽  
Animal Farm ◽  
Sources Of Contamination

Abstract Antibiotic resistant bacteria and genes which confer resistance to antibiotics from human/animal sources are currently considered a serious environmental and a public health concern. This problem is still little investigated in aquatic environment of developing countries according to the different climatic conditions. In this research, the total bacterial load, the abundance of relevant bacteria (Escherichia coli (E. coli), Enterococcus (Ent), and Pseudomonas), and antibiotic resistance genes (ARGs: blaOXA-48, blaCTX-M, sul1, sul2, sul3, and tet(B)) were quantified using Quantitative Polymerase Chain Reaction (qPCR) in sediments from two rivers receiving animal farming wastewaters under tropical conditions in Kinshasa, capital city of the Democratic Republic of the Congo. Human and pig host-specific markers were exploited to examine the sources of contamination. The total bacterial load correlated with relevant bacteria and genes blaOXA-48, sul3, and tet(B) (P value < 0.01). E. coli strongly correlated with 16s rDNA, Enterococcus, Pseudomonas spp., blaOXA-48, sul3, and tet(B) (P value < 0.01) and with blaCTX-M, sul1, and sul2 at a lower magnitude (P value < 0.05). The most abundant and most commonly detected ARGs were sul1, and sul2. Our findings confirmed at least two sources of contamination originating from pigs and anthropogenic activities and that animal farm wastewaters didn’t exclusively contribute to antibiotic resistance profile. Moreover, our analysis sheds the light on developing countries where less than adequate infrastructure or lack of it adds to the complexity of antibiotic resistance proliferation with potential risks to the human exposure and aquatic living organisms. This research presents useful tools for the evaluation of emerging microbial contaminants in aquatic ecosystems which can be applied in the similar environment.

Rapid detection of antibiotic resistance genes in lactic acid bacteria using PMMA-based microreactor arrays

2020 ◽  
Vol 104 (14) ◽  
pp. 6375-6383
Author(s):  
Zengjun Jin ◽  
Guotao Ding ◽  
Guoxing Yang ◽  
Guiying Li ◽  
Wei Zhang ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Resistance Genes ◽  
Rapid Detection ◽  
Antibiotic Resistance Genes

scholarly journals Fecal pollution explains antibiotic resistance gene abundances in anthropogenically impacted environments

2018 ◽  
Author(s):  
Karkman Antti ◽  
Pärnänen Katariina ◽  
Larsson D.G. Joakim
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Gene ◽  
Resistance Genes ◽  
Selection Pressure ◽  
Pathogenic Bacteria ◽  
Antibiotic Resistance Gene ◽  
Fecal Pollution ◽  
Metagenomic Data ◽  
Resistant Bacteria ◽  
Environmental Selection

AbstractDischarge of treated sewage leads to release of antibiotic resistant bacteria, resistance genes and antibiotic residues to the environment. Such pollution can directly contribute to increased morbidity caused by the transmission of resistant fecal pathogens. Residual antibiotics in wastewaters have been speculated to select for resistant bacteria and thereby promote the evolution and emergence of new resistance factors. Increased abundance of antibiotic resistance genes in sewage and sewage-impacted environments may, however, simply be a result of fecal contamination with resistant bacteria rather than caused by an on-site selection pressure. In this study we have disentangled these two alternative scenarios by relating the relative resistance gene abundance to the accompanying extent of fecal pollution in publicly available metagenomic data. This was possible by analyzing the abundance of a newly discovered phage which is exceptionally abundant in, and specific to, human feces. The presence of resistance genes could largely be explained by fecal pollution, with no clear signs of selection in the environment, the only exception being environments polluted by very high levels of antibiotics from manufacturing where selection is evident. Our results demonstrate the necessity to take in to account the fecal pollution levels to avoid making erroneous assumptions regarding environmental selection of antibiotic resistance. The presence or absence of selection pressure has major implications for what the risk scenarios are (transmission versus evolution) and for what mitigations (reducing pathogenic bacteria or selective agents) should be prioritized to reduce health risks related to antibiotic resistance in the environment.

scholarly journals Determination of Antimicrobial Effects of Probiotic Lactic Acid Bacteria and Garlic Extract Against Some Foodborn Pathogenic Bacteria

2017 ◽  
Vol 5 (2) ◽  
pp. 125 ◽  
Author(s):  
Selin Kalkan ◽  
Elçin Taş ◽  
Zerrin Erginkaya ◽  
Emel Ünal Turhan
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Bacillus Cereus ◽  
Pathogenic Bacteria ◽  
Meat Product ◽  
Starter Cultures ◽  
Garlic Extract ◽  
Resistant Bacteria

In this study, it was investigated that the inhibition effect of some lactic acid bacteria (Lactobacillus acidophilus NCC68, Lactobacillus casei Shirota, Lactobacillus rhamnosus (Ezal, commercial starter cultures)) which possessed with probiotic characteristics, against Bacillus cereus, Salmonella Enteritidis, Escherichia coli, Escherichia coli 0157:H7 ATCC 35150 and Staphylococcus aureus ATCC 25923. Besides, the inhibitory effect of probiotic cultures which used with meat and meat product additives that garlic extract over the antagonistic effects of sensitive pathogens were investigated in vitro. Consequently, the whole of lactic acid bacteria and garlic extract which were used in this study, showed inhibition effects against all selected pathogenic bacteria. Staphylococcus aureus ATCC 25923 was determined as the most sensitive pathogenic bacteria while Bacillus cereus was the most resistant bacteria against lactic acid bacteria and garlic extract. There was a distinctive increase in inhibition effects were observed by used of a combination with lactic acid bacteria and garlic extract.

scholarly journals Characterization of Erythromycin and Tetracycline Resistance in Lactobacillus fermentum Strains

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Elizaveta Anisimova ◽  
Dina Yarullina
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Pathogenic Bacteria ◽  
Tetracycline Resistance ◽  
Lactobacillus Fermentum ◽  
Monitoring And Control ◽  
Erythromycin Resistance ◽  
Phenotypic Resistance ◽  
Tetracycline Resistance Genes ◽  
Resistance Determinants

Lactobacillus fermentum colonizing gastrointestinal and urogenital tracts of humans and animals is widely used in manufacturing of fermented products and as probiotics. These bacteria may function as vehicles of antibiotic resistance genes, which can be transferred to pathogenic bacteria. Therefore, monitoring and control of transmissible antibiotic resistance determinants in these microorganisms is necessary to approve their safety status. The aim of this study was to characterize erythromycin and tetracycline resistance of L. fermentum isolates and to estimate the potential transfer of resistance genes from lactobacilli to the other Gram-positive and Gram-negative bacteria. Among six L. fermentum strains isolated from human feces and commercial dairy products, five strains demonstrated phenotypic resistance to tetracycline. PCR screening for antibiotic resistance determinants revealed plasmid-located tetracycline resistance genes tet(K) and tet(M) in all strains and erythromycin resistance genes erm(B) in the chromosome of L. fermentum 5-1 and erm(C) in the plasmid of L. fermentum 3-4. All tested lactobacilli lacked conjugative transposon Tn916 and were not able to transfer tetracycline resistance genes to Staphylococcus aureus, Staphylococcus epidermidis, Listeria monocytogenes, Acinetobacter baumannii, Citrobacter freundii, and Escherichia coli by filter mating. Staphylococcus haemolyticus did not accept erythromycin resistance genes from corresponding Lactobacillus strains. Thus, in the present study, L. fermentum was not implicated in the spread of erythromycin and tetracycline resistance, but still these strains pose the threat to the environment and human health because they harbored erythromycin and tetracycline resistance genes in their plasmids and therefore should not be used in foods and probiotics.

scholarly journals Antibiotic-Resistant Bacteria in Aquaculture and Climate Change: A Challenge for Health in the Mediterranean Area

2021 ◽  
Vol 18 (11) ◽  
pp. 5723
Author(s):  
Milva Pepi ◽  
Silvano Focardi
Keyword(s):  
Climate Change ◽  
Antibiotic Resistance ◽  
Human Health ◽  
Resistance Genes ◽  
Pathogenic Bacteria ◽  
Hot Spot ◽  
Mediterranean Area ◽  
Resistant Bacteria ◽  
Cell Physiology ◽  
The Mediterranean

Aquaculture is the productive activity that will play a crucial role in the challenges of the millennium, such as the need for proteins that support humans and the respect for the environment. Aquaculture is an important economic activity in the Mediterranean basin. A great impact is presented, however, by aquaculture practices as they involve the use of antibiotics for treatment and prophylaxis. As a consequence of the use of antibiotics in aquaculture, antibiotic resistance is induced in the surrounding bacteria in the column water, sediment, and fish-associated bacterial strains. Through horizontal gene transfer, bacteria can diffuse antibiotic-resistance genes and mobile resistance genes further spreading genetic determinants. Once triggered, antibiotic resistance easily spreads among aquatic microbial communities and, from there, can reach human pathogenic bacteria, making vain the use of antibiotics for human health. Climate change claims a significant role in this context, as rising temperatures can affect cell physiology in bacteria in the same way as antibiotics, causing antibiotic resistance to begin with. The Mediterranean Sea represents a ‘hot spot’ in terms of climate change and aspects of antibiotic resistance in aquaculture in this area can be significantly amplified, thus increasing threats to human health. Practices must be adopted to counteract negative impacts on human health, with a reduction in the use of antibiotics as a pivotal point. In the meantime, it is necessary to act against climate change by reducing anthropogenic impacts, for example by reducing CO2 emissions into the atmosphere. The One Health type approach, which involves the intervention of different skills, such as veterinary, ecology, and medicine in compliance with the principles of sustainability, is necessary and strongly recommended to face these important challenges for human and animal health, and for environmental safety in the Mediterranean area.

Sign in / Sign up

Export Citation Format

Share Document