Impact of polymorphisms in blaZ, blaR1 and blaI genes and their relationship with β-lactam resistance in S. aureus strains isolated from bovine mastitis

Rocha, Gabriela Dias; Nogueira, Joel Fonseca; Santos, Marion Venâncio Gomes dos; Boaventura, Joanna Adrielly; Soares, Riani Ananda Nunes; Gouveia, João José de Simoni; Costa, Mateus Matiuzzi da; Gouveia, Gisele Veneroni

doi:10.1016/j.micpath.2022.105453

Cited by 11 publications

(14 citation statements)

References 38 publications

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“…Most of these genes are located on plasmids but are also present on chromosomes. 87 When β-lactam antibiotics lacks, BlaI binds to the conserved sequence TACA/TGTA of blaZ promoter, which inhibits blaZ transcription and thus inhibits the production of β-lactamase. However, when β-lactam antibiotics exists, the antibiotics can bind with blaR1 to remove the inhibitory effect of blaI-blaZ and then produce β-lactamase.…”

Section: Resistance Mechanisms Of Mrsamentioning

confidence: 99%

Progress in the Prevalence, Classification and Drug Resistance Mechanisms of Methicillin-Resistant Staphylococcus aureus

Hou¹,

Liu²,

Wei³

et al. 2023

IDR

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Staphylococcus aureus is a common human pathogen with a variety of virulence factors, which can cause multiple infectious diseases. In recent decades, due to the constant evolution and the abuse of antibiotics, Staphylococcus aureus was becoming more resistant, the infection rate of MRSA remained high, and clinical treatment of MRSA became more difficult. The genetic diversity of MRSA was mainly represented by the continuous emergence of epidemic strains, resulting in the constant changes of epidemic clones. Different classes of MRSA resulted in different epidemics and resistance characteristics, which could affect the clinical symptoms and treatments. MRSA had also spread from traditional hospitals to community and livestock environments, and the new clones established a relationship between animals and humans, promoting further evolution of MRSA. Since the resistance mechanism of MRSA is very complex, it is important to clarify these resistance mechanisms at the molecular level for the treatment of infectious diseases. We firstly described the diversity of SCC mec elements, and discussed the types of SCC mec , its drug resistance mechanisms and expression regulations. Then, we described how the vanA operon makes Staphylococcus aureus resistant to vancomycin and its expression regulation. Finally, a brief introduction was given to the drug resistance mechanisms of biofilms and efflux pump systems. Analyzing the resistance mechanism of MRSA can help study new anti-infective drugs and alleviate the evolution of MRSA. At the end of the review, we summarized the treatment strategies for MRSA infection, including antibiotics, anti-biofilm agents and efflux pump inhibitors. To sum up, here we reviewed the epidemic characteristics of Staphylococcus aureus , summarized its classifications, drug resistance mechanisms of MRSA (SCC mec element, vanA operon, biofilm and active efflux pump system) and novel therapy strategies, so as to provide a theoretical basis for the treatment of MRSA infection.

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Section: Resistance Mechanisms Of Mrsamentioning

confidence: 99%

Progress in the Prevalence, Classification and Drug Resistance Mechanisms of Methicillin-Resistant Staphylococcus aureus

Hou¹,

Liu²,

Wei³

et al. 2023

IDR

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“…This is most likely driven by the different bacteria that were present in contaminated samples contrasted to controls. Genes involved in macrolide resistance were seen in contaminated kibble as well as beta-lactam genes bla R1 and bla I, which influence expression of bla Z and penicillin binding protein 2a (PBP 2a) and contribute to methicillin resistance ( 35 , 36 ). The bla 1 gene was observed in control samples, typically associated with ampicillin resistance.…”

Section: Resultsmentioning

confidence: 99%

Paired metagenomic and chemical evaluation of aflatoxin-contaminated dog kibble

Ottesen,

Kocurek,

Reed

et al. 2024

Front. Vet. Sci.

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IntroductionIdentification of chemical toxins from complex or highly processed foods can present ‘needle in the haystack’ challenges for chemists. Metagenomic data can be used to guide chemical toxicity evaluations by providing DNA-based description of the wholistic composition (eukaryotic, bacterial, protozoal, viral, and antimicrobial resistance) of foods suspected to harbor toxins, allergens, or pathogens. This type of information can focus chemistry-based diagnostics, improve hazard characterization and risk assessment, and address data gaps. Additionally, there is increasing recognition that simultaneously co-occurring mycotoxins, either from single or multiple species, can impact dietary toxicity exposure. Metagenomic data provides a way to address data gaps related to co-occurrence of multiple fungal species.MethodsPaired metagenomic and chemical data were used to evaluate aflatoxin-contaminated kibble with known levels of specific mycotoxins. Kibble was ground to a fine powder for both chemical and molecular analyses. Chemical analyses were performed with Liquid Chromatography Mass Spectrometry (LCMS) and according to the AOAC Official method 2005.08: Aflatoxins in Corn, Raw Peanuts, and Peanut Butter using Liquid Chromatography with Post-Column Photochemical Derivatization. Metagenomes were created from DNA extracted from ground kibble and sequenced on an Illumina NextSeq 2000 with an average sequence depth of 180 million reads per replicate.Results and discussionMetagenomic data demonstrated that the abundance of DNA from putative aflatoxigenic Aspergillus spp. correlated with the levels of aflatoxin quantified by LCMS. Metagenomic data also identified an expansive range of co-occurring fungal taxa which may produce additional mycotoxins. DNA data paired with chemical data provides a novel modality to address current data gaps surrounding dietary mycotoxin exposure, toxigenic fungal taxonomy, and mycotoxins of emerging concern.

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“…By means of milk inflammation indicators, i.e., SCC and DSCC, samples were grouped as depicted in Figure 4. [20] were used: group 1 (SCC < 200,000 cells/mL and DSCC < 65%), group 2 (SCC < 200,000 cells/mL and DSCC ≥ 65%), group 3 (SCC ≥ 200,000 cells/mL and DSCC ≥ 65%), and group 4 (SCC ≥ 200,000 cells/mL and DSCC < 65%).…”

Section: Pathogens and Udder Healthmentioning

confidence: 99%

“…In group 4, where only SCC was high, pathogen DNA was detected in 42.93% and 58.62% of STER and DHI samples, respectively. In both the sets, the group with the greatest number of samples free of pathogens was group 1, where both SCC and DSCC were low (35.28% for STER and [20] were used: group 1 (SCC < 200,000 cells/mL and DSCC < 65%), group 2 (SCC < 200,000 cells/mL and DSCC ≥ 65%), group 3 (SCC ≥ 200,000 cells/mL and DSCC ≥ 65%), and group 4 (SCC ≥ 200,000 cells/mL and DSCC < 65%).…”

Section: Pathogens and Udder Healthmentioning

confidence: 99%

Pathogen Detection via Quantitative PCR in Milk of Healthy Cows Collected Using Different Sampling Protocols

et al. 2023

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In this study we evaluated the prevalence of pathogens detected via quantitative PCR (qPCR) in milk from apparently healthy cows to identify the most common etiological agents present in Italian dairy farms. Milk samples were collected using a sterile protocol at quarter-level (3239 samples, 822 cows) and a conventional protocol at udder level as composite milk from the functional quarters of each cow (5464 samples, 5464 cows). The qPCR commercial kit detected Mycoplasma bovis, Mycoplasma spp., Staphylococcus aureus, coagulase-negative staphylococci (CNS), Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis, Prototheca spp., Escherichia coli, Klebsiella spp., Enterococcus spp. and Lactococcus lactis ssp. lactis as well as DNA from the penicillin resistance β-lactamase gene from staphylococci. The prevalence of specific DNA was calculated based on its presence or absence in the samples, factoring in both the sampling protocols and herds. Regardless of the sampling protocol used, the most frequently detected pathogens were CNS (26.6% in sterile and 13.9% in conventional protocol) and Streptococcus uberis (9.6% and 16.5%, respectively). These results underscore the necessity for pathogen-specific interventions at the farm level to enhance the udder health of dairy cows via management recommendations.

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Impact of polymorphisms in blaZ, blaR1 and blaI genes and their relationship with β-lactam resistance in S. aureus strains isolated from bovine mastitis

Cited by 11 publications

References 38 publications

Progress in the Prevalence, Classification and Drug Resistance Mechanisms of Methicillin-Resistant Staphylococcus aureus

Progress in the Prevalence, Classification and Drug Resistance Mechanisms of Methicillin-Resistant Staphylococcus aureus

Paired metagenomic and chemical evaluation of aflatoxin-contaminated dog kibble

Pathogen Detection via Quantitative PCR in Milk of Healthy Cows Collected Using Different Sampling Protocols

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