Ancestral hemoglobins in Archaea
Ancestral hemoglobins in Archaea
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DOI：
10.1073/pnas.0308657101
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发表时间：
2004-04-27
影响因子：
11.1
通讯作者：
Alam, M
中科院分区：
文献类型：
--
作者：
Freitas, TAK;Hou, SB;Alam, M
血红蛋白在真核生物和细菌中普遍存在，但到目前为止，还没有在真核生物中发现。最近发现的微生物家族的球蛋白耦合血红素为基础的传感器的系统发育分析表明，这些传感器的后裔从一个古老的球蛋白只有祖细胞，或原球蛋白（PGB）。在这里，我们报告的发现和表征的两个Pgbs从的pestea：APPGB从专性好氧超嗜热Aeropyrum pernix，和MaPGB从严格厌氧产甲烷菌Methanosarcina acetivorans。ApPgb和MaPgb都通过血红素部分结合分子氧、一氧化氮和一氧化碳，血红素部分通过F8组氨酸（组氨酸120）与蛋白质配位。我们假设这些古球蛋白是当代血红蛋白的祖先。
Hemoglobins are ubiquitous in Eukarya and Bacteria but, until now, have not been found in Archaea. A phylogenetic analysis of the recently revealed microbial family of globin-coupled heme-based sensors suggests that these sensors descended from an ancient globin-only progenitor, or a protoglobin (Pgb). Here, we report the discovery and characterization of two Pgbs from the Archaea: ApPgb from the obligately aerobic hyperthermophile Aeropyrum pernix, and MaPgb from the strictly anaerobic methanogen Methanosarcina acetivorans. Both ApPgb and MaPgb bind molecular oxygen, nitric oxide, and carbon monoxide by means of a heme moiety that is coordinated to the protein through the F8 histidine (histidine 120). We postulate that these archaeal globins are the ancestors of contemporary hemoglobins.