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本文综述了超广谱 β 内酰胺酶 (extended spectrum β lactamases ,ESBLs)的分类研究进展以及ESBLs分子进化研究进展。ESBLs可分为TEM族、SHV族、CTX M族、OXA族及一些不属于上述任何一个家族的类型 ,其中以TEM族及SHV族ESBLs的种类最多 ,CTX M族、OXA族ESBLs的种类也在迅速增多。TEM族、SHV族ESBLs通常由其亲代广谱酶发生氨基酸取代衍生而来 ,氨基酸的插入和缺失也可使酶具有ESBLs活性。ESBLs的中性或近中性突变可能在其它突变的特定背景下发挥潜在作用 ,分析这类突变对ESBLs的分子进化及分子流行病学研究有重要意义。ESBLs进化的选择压力通常归因于氧亚胺 β 内酰胺类抗生素的使用强度 ,这类抗生素的选择压力还对启动子、拷贝数及其它基因起作用
This review summarizes the progress in the classification of extended spectrum β lactamases (ESBLs) and the molecular evolution of ESBLs. ESBLs can be divided into TEM family, SHV family, CTX M family, OXA family and some not belong to any of the above types of family, of which the most family of TEM and SHV ESBLs species, CTX M family, OXA family ESBLs species Rapid increase. The TEM family and SHV family ESBLs are usually derived from the substitution of amino acids by their parental broad-spectrum enzymes. The insertion and deletion of amino acids also allow the enzyme to have ESBLs activity. Neutral or near-neutral mutations in ESBLs may play a potential role in specific contexts of other mutations, and analysis of these mutations is of great importance for the molecular evolution and molecular epidemiology of ESBLs. The pressure of choice for evolution of ESBLs is usually attributed to the strength of use of oxyimine beta lactam antibiotics and the selective pressure of such antibiotics also affects promoters, copy numbers and other genes