Takaya N, Suzuki S, Matsuo M, Shoun H
Institute of Applied Biochemistry, University of Tsukuba, Japan.
FEBS Lett. 1997 Sep 15;414(3):545-8. doi: 10.1016/s0014-5793(97)01069-7.
A flavohemoprotein was purified to homogeneity from the denitrifying fungus Fusarium oxysporum. The purified protein existed as a monomer with a molecular weight of 44 kDa. It was purified in an oxidized form and exhibited the absorption maxima at 401, 540 and 643 nm in its resting form, and at 434 and 555 nm upon reduction with dithionite, respectively. The protein contained 0.5 mol protoheme/mol and 1.1 mol FAD/mol, respectively. When the resting flavohemoprotein was aerobically incubated with NAD(P)H, it was converted to a spectral species that is spectrally very similar to oxyhemoglobins. These properties are characteristics of flavohemoglobins (FHb) of Alcaligenes eutrophus, Escherichia coli, and baker's yeast. Further the amino terminal amino acid sequence of the protein of F. oxysporum was similar to those of these FHbs. These results suggest that the isolated flavohemoprotein of F. oxysporum would be a counterpart of the proteins in the FHb family.
从反硝化真菌尖孢镰刀菌中纯化出一种黄素血红蛋白，使其达到同质。纯化后的蛋白质以单体形式存在，分子量为44 kDa。它以氧化形式纯化，在静止状态下其吸收峰分别位于401、540和643 nm，用连二亚硫酸盐还原后，吸收峰分别位于434和555 nm。该蛋白质分别含有0.5 mol原血红素/mol和1.1 mol FAD/mol。当静止的黄素血红蛋白与NAD(P)H进行需氧孵育时，它会转化为一种光谱特性与氧合血红蛋白非常相似的光谱物种。这些特性是嗜碱产碱菌、大肠杆菌和面包酵母中黄素血红蛋白（FHb）的特征。此外，尖孢镰刀菌蛋白质的氨基末端氨基酸序列与这些FHb的相似。这些结果表明，分离出的尖孢镰刀菌黄素血红蛋白可能是FHb家族中蛋白质的对应物。
