基因转移因子———一类在海洋中广泛存在的介导水平基因转移的新型生物因子

Gene Transfer Agent—a novel and widespread occurrence mechanism of gene exchange in ocean—A review

摘要:

摘要:基因转移因子(Gene Transfer Agent，GTA)是一种由细菌释放的、形态和有尾病毒类似的生物颗粒。GTA 颗粒携带的遗传物质是宿主基因组的随机小片段而不包含编码GTA 自身的基因或病毒基因组。根据4个模式菌株释放的GTA 的研究，GTA具有高效的，种间介导基因水平转移的功能。近年来大规模细菌基因组测序，发现编码GTA 的基因簇广泛存在于海洋细菌基因组上，GTA 是在海洋环境中发生水平基因转移的重要模式。本文在总结4 个模式菌株释放的GTA 的认识的基础上，着重描述海洋主要类群的细菌释放的GTA 的特征，讨论在海洋生态系统中，GTA 对水平基因转移的贡献，并对未来的研究进行了展望。

Abstract:

Abstract:Gene Transfer Agent (GTA) particles are released by bacteria and resemble small，tailed bacteriophages．GTA particles contain small，random pieces of host DNA rather than GTA structural genes or a phage genome．Gene transfer mediated by GTA is efficient and species specific based on knowledge of currently best studied GTAs produced by 4 anaerobes．Genome sequencing projects have revealed a remarkable distribution of GTA gene clusters in the genomes of marine bacterioplankton，implying GTA may be an important mechanism for horizontal gene transfer in ocean．On basis of characterization of the 4 best studied GTAs，this review described GTAs released by numerically dominant marine bacteria，discussed their properties that were important for horizontal gene transfer in ocean，and gave future perspectives to advance GTA research．