Westbye Alexander B, O'Neill Zoe, Schellenberg-Beaver Tegan, Beatty J Thomas
Department of Microbiology and Immunology, The University of British Columbia, Vancouver, BC, Canada.
Present address: Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, 't Horntje (Texel), Netherlands.
Microbiology (Reading). 2017 Sep;163(9):1355-1363. doi: 10.1099/mic.0.000519. Epub 2017 Sep 4.
Small bacteriophage-like particles called gene transfer agents (GTAs) that mediate DNA transfer between cells are produced by a variety of prokaryotes. The model GTA, produced by the alphaproteobacterium Rhodobacter capsulatus (RcGTA), is controlled by several cellular regulators, and production is induced upon entry into the stationary phase. We report that RcGTA production and gene transfer are stimulated by nutrient depletion. Cells depleted of organic carbon or blocked for amino acid biosynthesis increased RcGTA production and release from cells. Furthermore, cells lacking the sole RelA-SpoT homologue produced decreased levels of RcGTA, and the RNA polymerase omega (ω) subunit was required for appreciable production of RcGTA.
一种名为基因转移因子（GTA）的类似噬菌体的小颗粒可介导细胞间的DNA转移，多种原核生物均可产生这种颗粒。由α-变形菌荚膜红细菌（RcGTA）产生的典型GTA受多种细胞调节因子的控制，进入稳定期后会诱导其产生。我们报告称，营养物质耗竭会刺激RcGTA的产生和基因转移。缺乏有机碳或氨基酸生物合成受阻的细胞会增加RcGTA的产生并从细胞中释放出来。此外，缺乏唯一的RelA-SpoT同源物的细胞产生的RcGTA水平降低，而RNA聚合酶ω（ω）亚基是RcGTA大量产生所必需的。
