Genetic environment of the multi-resistance gene cfr in methicillin-resistant coagulase-negative staphylococci from chickens, ducks, and pigs in China.
The present study focussed on the analysis of the genetic environment of the multi-resistance gene cfr detected among 21, mostly methicillin-resistant, coagulase-negative Staphylococcus (CoNS) isolates obtained from chickens, ducks and pigs in China. It included sequencing of the regions up- and downstream of the cfr gene on various plasmid types in 13 isolates, such as pSS-02 and pSS-02-like (n=7), pSS-03-like (n=1), pJP1-like (n=3), pSS-04 (n=1) and pJP2 (n=1). This analysis revealed that insertion sequences (IS21-558, IS256, IS257, or IS1216E) and other resistance genes (aacA-aphD and aadD for aminoglycoside resistance, ble for bleomycin resistance, fosD for fosfomycin resistance, erm(B) and erm(C) for macrolide-lincosamide-streptogramin B resistance, or fexA for phenicol resistance) coexisted on the respective plasmids. In the chromosomal copies of cfr identified in eight S. lentus isolates, the cfr gene was found to be bracketed by insertion sequences, such as IS256 or ISEnfa5. Stability tests confirmed that all chromosomal cfr-containing regions could be looped out via IS-mediated recombination. The observations made in this study extend the rather rudimentary knowledge about the genetic environment of cfr in staphylococci from chickens and ducks and confirmed that insertion sequences play an important role in the dissemination of cfr, not only among different types of plasmids, but also for the integration in the chromosomal DNA.
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China.
Tao
T
He
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China.
Yang
Y
Wang
Institute of Farm Animal Genetics, Friedrich-Loeffler-Institut (FLI), Höltystr. 10, 31535 Neustadt-Mariensee, Germany.
Stefan
S
Schwarz
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China.
Qin
Q
Zhao
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China.
Jianzhong
J
Shen
Beijing Key Laboratory of Detection Technology for Animal-Derived Food Safety, College of Veterinary Medicine, China Agricultural University, Beijing 100193, PR China. Electronic address: wucm@cau.edu.cn.
Congming
C
Wu
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D002645:Chickens; D002681:China; D002876:Chromosomes, Bacterial; D003030:Coagulase / Q000172:deficiency*; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024881:Drug Resistance, Bacterial; D004372:Ducks; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010957:Plasmids; D017422:Sequence Analysis, DNA; D013203:Staphylococcal Infections / Q000382:microbiology / Q000662:veterinary; D013210:Staphylococcus / Q000235:genetics* / Q000302:isolation & purification*; D013552:Swine
D001426:Bacterial Proteins; D003030:Coagulase; D004251:DNA Transposable Elements; D004269:DNA, Bacterial
IS256; ISEnfa5; Linezolid; Poultry; Recombination