Mass Spectrometric Evidence for an Alternate Disulfide Bond in Chloroplast Fructose Bisphosphatase.
Mass mapping analysis based on cyanylation (CN) of the protein and CN-induced cleavage indicates that all three cysteine residues in the insertion into the light-activated pea leaf chloroplast fructose bisphosphatase (E.C. 3.1.3.11) are able to participate in disulfide bond formation. There is a major peak in the mass spectrum of the cleavage products indicating that Cys173 forms a disulfide bond with Cys153, consistent with the structure of the oxidized enzyme in PDB files 1d9q and 1dcu, and a minor peak indicating that Cys173 forms an alternate disulfide bond with Cys178. The Cys173-Cys178 disulfide bond was not apparent in the available crystal structures.
Wu
Wei
W
Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA.
Watson
J Throck
JT
Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA.
Stevens
Fred J
FJ
Biosciences Division, Argonne National Laboratory, Argonne, IL, 60439, USA.
Yousefzai
Ryan
R
Department of Biological Sciences, University of Illinois-Chicago, 845 West Taylor, Chicago, IL, 60680, USA.|Department of Chemistry, University of Illinois-Chicago, 845 West Taylor, Chicago, IL, 60680, USA.
Anderson
Louise E
LE
Department of Biological Sciences, University of Illinois-Chicago, 845 West Taylor, Chicago, IL, 60680, USA.|Department of Chemistry, University of Illinois-Chicago, 845 West Taylor, Chicago, IL, 60680, USA.