Wakabayashi S, Matsubara H, Webster D A
Nature. 1986;322(6078):481-3. doi: 10.1038/322481a0.
Vitreoscilla, a filamentous bacterium in the Beggiatoa family, synthesizes a soluble haem-protein which has two identical subunits of relative molecular mass 15,775 and two b haems per molecule. It is synthesized in relatively large quantities when the organism, a strict aerobe, is grown under hypoxic conditions. It forms a relatively stable oxygenated form which is spectrally similar to oxymyoglobin (oxyHb) and oxyhaemoglobin (oxyHb). The amino acid sequence of this protein has been determined and aligned to fit the helical regions of several animal and plant globins. This alignment is consistent with its being a structural homologue of the eucaryotic haemoglobins although it diverged from the others in the N-terminal region and may lack an A-helix. It showed the maximum sequence homology (24%) with lupin leghaemoglobin (Lb). Vitreoscilla Hb is the first bacterial haemoglobin to be sequenced. It may function to enable the organism to survive in oxygen-limited environments by acting as an oxygen storage-trap or to facilitate oxygen diffusion.
透明颤菌是贝日阿托氏菌科的一种丝状细菌，它能合成一种可溶性血红素蛋白，该蛋白有两个相对分子质量为15775的相同亚基，每个分子含有两个b型血红素。当这种严格需氧的生物体在缺氧条件下生长时，它会大量合成。它形成一种相对稳定的氧化形式，在光谱上与肌红蛋白（氧合肌红蛋白）和血红蛋白（氧合血红蛋白）相似。这种蛋白质的氨基酸序列已经确定，并进行了比对，以匹配几种动植物球蛋白的螺旋区域。这种比对与其作为真核血红蛋白的结构同源物是一致的，尽管它在N端区域与其他血红蛋白有所不同，可能缺少一个A螺旋。它与羽扇豆根瘤血红蛋白（Lb）的序列同源性最高（24%）。透明颤菌血红蛋白是第一个被测序的细菌血红蛋白。它的功能可能是通过充当氧气储存阱使生物体在氧气受限的环境中生存，或促进氧气扩散。
