Husain M, Davidson V L
J Biol Chem. 1986 Jul 5;261(19):8577-80.
When grown on methanol or methylamine, Paracoccus denitrificans synthesized three periplasmic soluble c-type cytochromes, cytochrome c550 and two additional cytochromes which were not present during growth on succinate and have not previously been characterized. These cytochromes have been separated from each other and their physical properties have been determined. The inducible cytochromes, c551i and c553i, exhibit Mr and pI values of 22,000 and 3.5, and 30,000 and 3.8, respectively. Cytochrome c553i binds CO. None of these cytochromes accepted electrons directly from methylamine dehydrogenase, but each accepted electrons from amicyanin, the electron acceptor for methylamine dehydrogenase. Cytochrome c551i was the most efficient electron acceptor for amicyanin, exhibiting a half-time of reaction at least 6 and 15 times faster than those observed for cytochromes c553i and c550, respectively.
当在甲醇或甲胺上生长时，反硝化副球菌合成了三种周质可溶性c型细胞色素，即细胞色素c550以及另外两种细胞色素，这两种细胞色素在琥珀酸盐上生长时不存在，且此前未被鉴定过。这些细胞色素已被彼此分离，并测定了它们的物理性质。可诱导的细胞色素c551i和c553i的相对分子质量和等电点分别为22,000和3.5，以及30,000和3.8。细胞色素c553i能结合一氧化碳。这些细胞色素均不能直接从甲胺脱氢酶接受电子，但每种都能从甲胺脱氢酶的电子受体氨腈蛋白接受电子。细胞色素c551i是氨腈蛋白最有效的电子受体，其反应半衰期分别比细胞色素c553i和c550至少快6倍和15倍。
