The Role of the si-Face Tyrosine of a Homodimeric Ferredoxin-NADP⁺ Oxidoreductase from Bacillus subtilis during Complex Formation and Redox Equivalent Transfer with NADP⁺/H and Ferredoxin.

ABSTRACT: In the crystal structure of ferredoxin-NADP⁺ oxidoreductase from Bacillus subtilis (BsFNR), Tyr50 stacks on the si-face of the isoalloxazine ring portion of the FAD prosthetic group. This configuration is highly conserved among the homodimeric ferredoxin-NAD(P)⁺ oxidoreductases (FNR) from Gram-positive bacteria and photosynthetic bacteria. In this report, pre-steady state reactions of Tyr50 variants with NADP⁺/NADPH and ferredoxin from B. subtilis (BsFd) were examined with stopped-flow spectrophotometry to assess the effects of the mutation on the formation of FNR-substrate complexes and following redox equivalent transfer. Mixing oxidized BsFNRs with NADPH resulted in a rapid complex formation followed by a rate-li

SUBMITTER: Seo D 

PROVIDER: S-EPMC10526003 | biostudies-literature | 2023 Sep

REPOSITORIES: biostudies-literature