Raymond Jason, Zhaxybayeva Olga, Gogarten J Peter, Gerdes Sveta Y, Blankenship Robert E
Department of Chemistry and Biochemistry, Arizona State University (ASU), Tempe, AZ 85287-1604, USA.
Science. 2002 Nov 22;298(5598):1616-20. doi: 10.1126/science.1075558.
The process of photosynthesis has had profound global-scale effects on Earth; however, its origin and evolution remain enigmatic. Here we report a whole-genome comparison of representatives from all five groups of photosynthetic prokaryotes and show that horizontal gene transfer has been pivotal in their evolution. Excluding a small number of orthologs that show congruent phylogenies, the genomes of these organisms represent mosaics of genes with very different evolutionary histories. We have also analyzed a subset of "photosynthesis-specific" genes that were elucidated through a differential genome comparison. Our results explain incoherencies in previous data-limited phylogenetic analyses of phototrophic bacteria and indicate that the core components of photosynthesis have been subject to lateral transfer.
光合作用过程对地球产生了深远的全球范围影响；然而，其起源和演化仍然是个谜。在此，我们报告了对所有五组光合原核生物代表进行的全基因组比较，并表明水平基因转移在它们的演化过程中起到了关键作用。除了少数显示一致系统发育关系的直系同源基因外，这些生物的基因组代表了具有非常不同演化历史的基因镶嵌体。我们还分析了通过差异基因组比较阐明的一组“光合作用特异性”基因。我们的结果解释了先前对光合细菌进行的数据有限的系统发育分析中的不一致性，并表明光合作用的核心成分经历了横向转移。
