细菌整合子——基因盒系统综述

Integrons and Gene Cassettes in the Bacteria

整合子是一个能够通过自身编码的整合酶来获取保外游离基因或基因片段并使之表达的遗传元件系统。根据整合子整合酶基因及其所捕获的基因盒功能的不同,整合子有两大类:抗性整合子和超级整合子。基因盒是能被整合酶整合到整合子上或是从整合子上切除的移动元件。基因盒一般包括2个功能性成分,即一个占该序列绝大部分的基因和另一个位于其下游的重组位点,其功能绝大多数是抗生素抗性基因,少数的是编码产物功能不甚清楚的ORF。整合子-基因盒系统在细菌抗生素抗性的获得、细菌基因组进化方面可能发挥着重要作用。

Integron, a mobile DNA element that can capture ,and carry genes based upon which integrase gene they contain, particularly those responsible for antibiotic resistance. It is the simplest mobile DNA element ever know and contains two parts which are gene cassettes and a recombined site called 59-base element. It has been divided two class, Resistant Integron and Super lntegron, based on integrase genes it contained and the difference of gene cassette＇s function it captured. Gene cassettes are the mobile element which can be integtated into or cutted out from integron by the integrases. Gene cassettes always have two functional parts including a gene which inhabited the most sequences and a recombined site downstream the gene. Most of gene cassettes are antibiotics-resistant gene, and others are the function-unknown ORE lntegron and gene cassettes are possibly important in the capture of antibiotics-resistant and evolution of bacteria genome.