Ducluzeau Anne-Lise, Ouchane Soufian, Nitschke Wolfgang
Laboratoire de Bioénergétique et Ingénierie des Protéines (UPR 9036), Institut de Biologie Structurale et Microbiologie, Centre National de la Recherche Scientifique, Marseille, France.
Mol Biol Evol. 2008 Jun;25(6):1158-66. doi: 10.1093/molbev/msn062. Epub 2008 Mar 18.
A survey of genomes for the presence of gene clusters related to cbb(3) oxidases detected bona fide members of the family in almost all phyla of the domain Bacteria. No archaeal representatives were found. The subunit composition was seen to vary substantially between clades observed on the phylogenetic tree of the catalytic subunit CcoN. The protein diade formed by CcoN and the monoheme cytochrome CcoO appears to constitute the functionally essential "core" of the enzyme conserved in all sampled cbb(3) gene clusters. The topology of the phylogenetic tree contradicts the scenario of a recent origin of cbb(3) oxidases and substantiates the status of this family as a phylogenetic entity on the same level as the other subgroups of the heme-copper superfamily (including nitric oxide reductase). This finding resuscitates and exacerbates the conundrum of the evolutionary origin of heme-copper oxidases.
一项关于基因组中与cbb(3)氧化酶相关基因簇存在情况的调查发现，在细菌域的几乎所有门中都检测到了该家族的真正成员。未发现古菌代表。在催化亚基CcoN的系统发育树上观察到的不同进化枝之间，亚基组成差异很大。由CcoN和单血红素细胞色素CcoO形成的蛋白质二联体似乎构成了在所有采样的cbb(3)基因簇中保守的该酶功能上必不可少的“核心”。系统发育树的拓扑结构与cbb(3)氧化酶近期起源的设想相矛盾，并证实了该家族作为一个系统发育实体的地位，与血红素-铜超家族的其他亚组（包括一氧化氮还原酶）处于同一水平。这一发现使血红素-铜氧化酶进化起源的难题再度出现且更加棘手。
