The aim of the present study was to determine the rate and mechanisms of resistance to macrolides, lincosamides, and streptogramin B (MLSB) antibiotics of Staphylococcus aureus collected in Central Greece. Of the 2,893 S. aureus collected during 2012-2017, 1,161 isolates (40.2%) exhibited resistance to at least one of the MLSB agents. The rate of erythromycin resistance was statistically significantly higher in methicillin-resistant S. aureus (MRSA) (58.6%) than in methicillin-sensitive S. aureus (MSSA) isolates (20.7%) (p = 0.002). Two hundred seventy-five representative MLSB-resistant S. aureus, including 81 MSSA and 194 MRSA isolates, were further studied. Thirty-eight MSSA isolates carried ermC, 26 MSSA were positive for ermA, whereas 17 isolates carried msrA gene. Among MRSA, the ermA gene was identified in the majority of the isolates (n = 153). Thirty-seven MRSA isolates carried ermC; three isolates carried msrA, whereas the remaining MRSA was positive for two genes (ermA and ermC). Phylogenetic analysis showed that ST225, which belongs to CC5, was the most prevalent, accounting for 137 MRSA isolates. Higher genetic diversity was found in the group of MSSA isolates, which comprised of 13 sequence types. Whole-genome sequencing data showed that all ermA-positive S. aureus, with the exception of one ST398 isolate, harbored the ermA-carrying Tn554 transposon integrated into their chromosomes. Furthermore, Illumina sequencing followed by polymerase chain reaction screening identified that ermC, which was identified in a polyclonal population of MSSA and MRSA isolates, was carried by small plasmids, like pNE131. These findings highlighted the important role of high-risk clones and of mobile elements carrying resistance genes in the successful dissemination of MLSB-resistant staphylococci.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální proteiny genetika MeSH
- fylogeneze MeSH
- genotyp MeSH
- lidé MeSH
- linkosamidy farmakologie MeSH
- makrolidy farmakologie MeSH
- methicilin rezistentní Staphylococcus aureus účinky léků genetika MeSH
- mikrobiální testy citlivosti metody MeSH
- mnohočetná bakteriální léková rezistence genetika MeSH
- stafylokokové infekce farmakoterapie mikrobiologie MeSH
- streptogramin B farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Řecko MeSH
The influence of specific and non-specific antibiotic pressure on in vivo spread of macrolide-lincosamide-streptogramin B (MLSB) resistance was evaluated in this study. Chickens repeatedly inoculated with Enterococcus faecalis harbouring the plasmid pAMβ1 carrying the erm(B) gene were perorally treated for one week with tylosin, lincomycin (both specific antibiotic pressure) and chlortetracycline (non-specific antibiotic pressure). Antibiotic non-treated but E. faecalis inoculated chickens served as a control. To quantify the erm(B) gene and characterise intestinal microflora, faecal DNA was analysed by qPCR and 454-pyrosequencing. Under the pressure of antibiotics, a significant increase in erm(B) was observed by qPCR. However, at the final stage of the experiment, an increase in erm(B) was also observed in two out of five non-treated chickens. In chickens treated with tylosin and chlortetracycline, the increase in erm(B) was accompanied by an increase in enterococci. However, E. faecalis was at the limit of detection in all animals. This suggests that the erm(B) gene spread among the gut microbiota other than E. faecalis. Pyrosequencing results indicated that, depending on the particular antibiotic pressure, different bacteria could be responsible for the spread of MLSB resistance. Different species of MLSB-resistant enterococci and streptococci were isolated from cloacal swabs during and after the treatment. PFGE analysis of MLSB-resistant enterococci revealed four clones, all differing from the challenge strain. All of the MLSB-resistant isolates harboured a plasmid of the same size as pAMβ1. This study has shown that MLSB resistance may spread within the gut microbiota under specific and non-specific pressure and even in the absence of any antimicrobial pressure. Finally, depending on the particular antibiotic pressure, different bacterial species seems to be involved in the spread of MLSB resistance.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální léková rezistence genetika MeSH
- chlortetracyklin farmakologie MeSH
- DNA primery genetika MeSH
- druhová specificita MeSH
- Enterococcus faecalis účinky léků genetika MeSH
- feces mikrobiologie MeSH
- grampozitivní bakteriální infekce veterinární MeSH
- kur domácí * MeSH
- linkosamidy farmakologie MeSH
- makrolidy farmakologie MeSH
- methyltransferasy genetika MeSH
- mikrobiální testy citlivosti MeSH
- molekulární sekvence - údaje MeSH
- nemoci drůbeže mikrobiologie MeSH
- neparametrická statistika MeSH
- plazmidy genetika MeSH
- polymerázová řetězová reakce veterinární MeSH
- přenos genů horizontální genetika MeSH
- pulzní gelová elektroforéza veterinární MeSH
- sekvence nukleotidů MeSH
- sekvenční analýza DNA MeSH
- streptogramin B farmakologie MeSH
- tylosin farmakologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The occurrence of staphylococci and enterococci expressing increased resistance to erythromycin (ERY) and, in particular, to macrolide-lincosamide-streptogramin B (MLS(B) ) antibiotics was investigated in dairy cattle, pigs and turkeys. Three hundred rectal (cloacal) swabs of each animal species were examined. A total of 120 and 71 staphylococci and enterococci, respectively, with increased resistance to ERY were identified. These were most frequent in turkeys (42.3% of positive animals), followed by pigs and dairy cattle (6.7% and 6.0% of positive animals, respectively). Similarly, MLS(B) -resistant isolates colonized predominantly turkeys (29.7% of animals), while their occurrence in pigs and dairy cattle was only sporadic (0.8% of animals). At least one of the erm genes encoding for MLS(B) resistance was found in 56.7% and 69.0% of staphylococci and enterococci, respectively. The erm(C) gene prevailed in staphylococci while the erm(B) gene was predominant in enterococci. Macrolide efflux genes msr(A) and msr(C) were also frequent in staphylococci and enterococci, respectively. Macrolide inactivation gene mph(C) occurred mainly in staphylococci. In staphylococci, methicillin resistance was rarely detected (7.5% of isolates), but resistance to telithromycin (ketolides) was frequent in both staphylococci and enterococci (89.2% and 47.9% of isolates, respectively). This study showed that turkeys represent an important source of ERY (MLS(B) )-resistant cocci. In addition, resistance to ketolides was also frequent.
- MeSH
- antibakteriální látky farmakologie MeSH
- bakteriální geny účinky léků MeSH
- bakteriální léková rezistence genetika MeSH
- bakteriální proteiny genetika metabolismus MeSH
- Enterococcus účinky léků genetika izolace a purifikace MeSH
- erythromycin farmakologie MeSH
- fenotyp MeSH
- genotyp MeSH
- krocani MeSH
- linkosamidy farmakologie MeSH
- makrolidy farmakologie MeSH
- mikrobiální testy citlivosti MeSH
- nemoci drůbeže MeSH
- prasata MeSH
- prevalence MeSH
- skot MeSH
- stafylokokové infekce farmakoterapie epidemiologie MeSH
- Staphylococcus účinky léků genetika izolace a purifikace MeSH
- streptogramin B farmakologie MeSH
- zvířata MeSH
- Check Tag
- skot MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
