Involvement of thioredoxin on the scaffold activity of NifU in heterocyst cells of the diazotrophic cyanobacterium Anabaena sp. strain PCC 7120

In this study, we investigated thioredoxin (Trx) networks in Anabaena using TrxM, and identified 16 and 38 candidate target proteins in heterocysts and vegetative cells, respectively, by Trx affinity chromatography (Motohashi et al. (Comprehensive survey of proteins targeted by chloroplast thioredoxin. Proc Natl Acad Sci USA, 2001;98, 11224–11229)). Among these, the Fe–S cluster scaffold protein NifU that facilitates functional expression of nitrogenase in heterocysts was found to be a potential TrxM target. Subsequently, we observed that the scaffold activity of N-terminal catalytic domain of NifU is enhanced in the presence of Trx-system, suggesting that TrxM is involved in the Fe–S cluster biogenesis.

Source: Journal of Biochemistry - August 29, 2015 Category: Biochemistry Authors: Nomata, J., Maeda, M., Isu, A., Inoue, K., Hisabori, T. Tags: Regular Papers Source Type: research