title: Structure requirements for disulfide bridge sulfitolysis of oxidized Escherichia coli thioredoxin studied by fluorescence spectroscopy.
abstract: Sulfitolysis of wild-type and four mutated Escherichia coli thioredoxins ([D26A]thioredoxin, [P34H]thioredoxin, [K36E]thioredoxin and endo-Arg33a-thioredoxin) has been investigated at millimolar concentrations of sulfite in the absence of protein-denaturing agents by fluorescence spectroscopy. Sulfitolysis of the single disulfide bridge of these proteins is associated with an increase in fluorescence emissions at 345 nm. Evaluation of the fluorescence emission spectra revealed that sulfitolysis of thioredoxins is a homogenous process. The reactivities of the thioredoxins are determined by negatively charged (Asp26) or positively charged (Lys36) amino acid residues near the active site disulfide bridge.
authors.affiliation: Fachbereich Biologie-Chemie, Universität Kassel, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Häberlein
mesh_terms: D000595:Amino Acid Sequence; D001216:Asparagine / Q000378:metabolism; D004220:Disulfides / Q000737:chemistry; D004926:Escherichia coli / Q000737:chemistry*; D008239:Lysine / Q000378:metabolism; D008969:Molecular Sequence Data; D015394:Molecular Structure; D009154:Mutation; D013050:Spectrometry, Fluorescence; D013447:Sulfites / Q000378:metabolism; D013879:Thioredoxins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D004220:Disulfides; D013447:Sulfites; D013879:Thioredoxins; D001216:Asparagine; D008239:Lysine