Abstract: With the wide use of antibiotics in veterinary clinic, the number of drug-resistant strains is increasing year by year, so the research on the mechanism of drug resistance has become a hot spot. Resistance gene cfr (chloramphenicol-florfenicol resistance) can encode to synthesize 23S rRNA methylation enzyme of bacteria. This enzyme can affect the combination of antimicrobial agents with transpeptidase and make bacteria resistant. The strains carrying cfr gene were resistant to chloramphenicol, linamide, truncated pleurodin, streptavidin A and oxazolidinone, which resulted in multidrug resistance to bacteria. Therefore, the study on the mechanism of action and transmission of drug resistance gene cfr is the key point for the backerial resistance research. In this paper, the discovery, harm, drug resistance mechanism, transmission mechanism and prevalence of multidrug resistance gene cfr in different types of bacteria were reviewed. The problems existing in present research, and suggestions for future development prospects were discussed. It provided reference and basis for the further establishment of cfr gene detection network, the development of new drugs and blocking the transmission of cfr gene.

Key words: cfr gene, gram-positive bacteria, gram-negative bacteria, resistance mechanism, transmission mechanism

摘要： 随着抗菌药物在兽医临床的广泛使用，耐药菌株数量逐年上升，使耐药机制成为研究热点。耐药基因cfr（chloramphenicol-florfenicol resistance）可编码合成细菌的23S rRNA甲基化酶，该酶可影响抗菌药物与转肽酶结合，使细菌产生耐药性。而携带cfr基因的菌株可对氯霉素类、林可酰胺类、截短侧耳素、链阳菌素A和恶唑烷酮类五大类常用抗菌药物耐药，使细菌产生多药耐药。因此耐药基因cfr的作用机理和传播机制的研究是细菌耐药性研究的关键。对多重耐药基因cfr的发现、危害、耐药机制及其在不同类型菌体中的传播机制和流行情况进行综述，讨论了目前研究中存在的问题，并对未来的发展提出建议，可为进一步建立cfr基因检测网、新药研制和阻断cfr基因的传播提供参考和依据。

关键词: cfr基因, 革兰氏阳性菌, 革兰氏阴性菌, 耐药机制, 传播机制