title: Defining the plant disulfide proteome.
abstract: There is considerable interest in redox regulation and new targets for thioredoxin and glutaredoxin are now being identified. It would be of great benefit to the field to have a list of all possible candidates for redox regulation--that is all disulfide proteins in plant. We developed a simple and very powerful method for identifying proteins with disulfide bonds in vivo. In this method, free thiols in proteins are fully blocked by alkylation, following which disulfide cysteines are converted to sulfhydryl groups by reduction. Finally, proteins with sulfhydryls are isolated by thiol affinity chromatography. Our method is unique in that membrane proteins as well as water-soluble proteins are examined for their disulfide nature. By applying this method to Arabidopsis thaliana we identified 65 putative disulfide proteins, including 20 that had not previously been demonstrated to be regulated by redox state. The newly identified, possibly redox-regulated proteins include: violaxanthin de-epoxidase, two oxygen-evolving enhancer proteins, carbonic anhydrase, photosystem I reaction center subunit N, photosystem I subunit III, S-adenosyl-L-methionine carboxyl methyltransferase, guanylate kinase, and bacterial mutT homolog. Possible functions of disulfide bonding in these proteins are discussed.
authors.affiliation: Division of Applied Life Science, Gyeongsang National University, Chinju, Korea.
authors.forename: Kyunghee
authors.initials: K
authors.lastname: Lee
authors.forename: Jungwha
authors.initials: J
authors.lastname: Lee
authors.forename: Youngmin
authors.initials: Y
authors.lastname: Kim
authors.forename: Dongwon
authors.initials: D
authors.lastname: Bae
authors.forename: Kyu Young
authors.initials: KY
authors.lastname: Kang
authors.forename: Sung C
authors.initials: SC
authors.lastname: Yoon
authors.forename: Dongbin
authors.initials: D
authors.lastname: Lim
mesh_terms: D017360:Arabidopsis / Q000737:chemistry; D002846:Chromatography, Affinity; D004220:Disulfides; D010084:Oxidation-Reduction; D010940:Plant Proteins / Q000302:isolation & purification*; D011506:Proteins / Q000737:chemistry / Q000302:isolation & purification*; D020543:Proteome / Q000302:isolation & purification*; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D004220:Disulfides; D010940:Plant Proteins; D011506:Proteins; D020543:Proteome; D013438:Sulfhydryl Compounds