Hase T, Wada K, Ohmiya M, Matsubara H
J Biochem. 1976 Nov;80(5):993-9. doi: 10.1093/oxfordjournals.jbchem.a131387.
The amino acid sequence of the major component of ferredoxin isolated from a blue-green alga, Nostoc muscorum, grown under N2 as the sole nitrogen source has been studied. The use of a combination of sequence analyzer, carboxypeptidases, and manual Edman degradations on tryptic and chymotryptic peptides of carboxymethylferredoxin has established the amino acid seuqence, which consists of 98 amino acid residues. Only four cysteine residues were present, located at positions 41, 46, 49, and 79. These residues must fulfil the minimum requirement in this ferredoxin for the chelation of two iron atoms, as postulated previously. The sequence is similar to those of Spirulina ferredoxins in having two extra residues at positions 10 and 14 compared with other chloroplast-type ferredoxins. Sequence comparison among blue-green algal ferredoxins suggests that Nostoc muscorum ferredoxin is more closely related to Spirulina ferredoxins than to Aphanothece major ferredoxin.
对从以氮气作为唯一氮源生长的蓝藻念珠藻中分离出的铁氧化还原蛋白主要成分的氨基酸序列进行了研究。通过对羧甲基铁氧化还原蛋白的胰蛋白酶和胰凝乳蛋白酶肽段结合序列分析仪、羧肽酶以及手动埃德曼降解法，确定了由98个氨基酸残基组成的氨基酸序列。仅存在四个半胱氨酸残基，位于第41、46、49和79位。如先前假设的那样，这些残基必须满足该铁氧化还原蛋白中螯合两个铁原子的最低要求。该序列与螺旋藻铁氧化还原蛋白的序列相似，与其他叶绿体型铁氧化还原蛋白相比，在第10和14位有两个额外的残基。蓝藻铁氧化还原蛋白之间的序列比较表明，念珠藻铁氧化还原蛋白与螺旋藻铁氧化还原蛋白的关系比与大鞘丝藻铁氧化还原蛋白的关系更为密切。
