Sabehi Gazalah, Loy Alexander, Jung Kwang-Hwan, Partha Ranga, Spudich John L, Isaacson Tal, Hirschberg Joseph, Wagner Michael, Béjà Oded
Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
PLoS Biol. 2005 Aug;3(8):e273. doi: 10.1371/journal.pbio.0030273. Epub 2005 Jul 19.
Proteorhodopsin phototrophy was recently discovered in oceanic surface waters. In an effort to characterize uncultured proteorhodopsin-exploiting bacteria, large-insert bacterial artificial chromosome (BAC) libraries from the Mediterranean Sea and Red Sea were analyzed. Fifty-five BACs carried diverse proteorhodopsin genes, and we confirmed the function of five. We calculate that proteorhodopsin-exploiting bacteria account for 13% of microorganisms in the photic zone. We further show that some proteorhodopsin-containing bacteria possess a retinal biosynthetic pathway and a reverse sulfite reductase operon, employed by prokaryotes oxidizing sulfur compounds. Thus, these novel phototrophs are an unexpectedly large and metabolically diverse component of the marine microbial surface water.
视紫质光养作用最近在海洋表层水域被发现。为了对未培养的利用视紫质的细菌进行特性描述，分析了来自地中海和红海的大插入片段细菌人工染色体（BAC）文库。55个BAC携带了不同的视紫质基因，我们证实了其中5个的功能。我们计算出利用视紫质的细菌占光合层微生物的13%。我们进一步表明，一些含视紫质的细菌拥有视网膜生物合成途径和一个由氧化硫化合物的原核生物所使用的反向亚硫酸盐还原酶操纵子。因此，这些新型光养生物是海洋微生物表层水一个出人意料的庞大且代谢多样的组成部分。
