Eschenbrenner M, Covès J, Fontecave M
Laboratoire d'Etudes Dynamiques et Structurales de la Sélectivité, Unité de Recherche Associée au Centre National de la Recherche Scientifique no. 332, Université Joseph Fourier, Grenoble, France.
FEBS Lett. 1995 Oct 23;374(1):82-4. doi: 10.1016/0014-5793(95)01081-o.
The flavoprotein component (SiR-FP) of the sulfite reductase of E. coli is an octamer of the 66 kDa alpha subunit. It was shown to be cleaved in two peptide fragments. The 23 kDa fragment has been purified as a polymer of 8-10 subunits. It corresponds to the N-terminal part of the native protein and was shown to contain essentially FMN as cofactor. The 43 kDa fragment is monomeric. It contains exclusively FAD and remains able to catalyze efficiently NADPH-dependent reductions. One can conclude that each alpha-chain of SiR-FP is composed of two distinct domains, one binding FAD and the other FMN and that the FMN-binding domains cooperate for a head-to-head subunit interaction.
大肠杆菌亚硫酸盐还原酶的黄素蛋白组分（SiR-FP）是由66 kDaα亚基组成的八聚体。它被证明可裂解为两个肽片段。23 kDa的片段已被纯化，为8 - 10个亚基的聚合物。它对应于天然蛋白质的N端部分，并且已证明主要含有FMN作为辅因子。43 kDa的片段是单体。它仅含有FAD，并且仍然能够高效催化依赖NADPH的还原反应。可以得出结论，SiR-FP的每个α链由两个不同的结构域组成，一个结合FAD，另一个结合FMN，并且FMN结合结构域通过头对头的亚基相互作用进行协作。
