title: Analysis by limited proteolysis of domain organization and GSH-site arrangement of bacterial glutathione transferase B1-1.
abstract: Limited proteolysis method has been used to study the structure-function relationship of bacterial glutathione transferase (GSTB1-1). In absence of three-dimensional structural data of prokaryote GST, the results represent the first information concerning the G-site and domains organization of GSTB1-1. The tryptic cleavages occur mainly at the peptide bonds Lys35-Lys36 and Phe43-Leu44, generating two major molecular species of 20-kDa, 3-kDa and traces of 10-kDa. 1-chloro-2,4-dinitrobenzene favoured the proteolysis of the 20-kDa fragment markedly enhancing the production of the 10-kDa peptide by cleaving the chemical bonds Lys87-Ala88 and Arg91-Tyr92. The tryptic cleavage sites of GSTB1-1 was found to be located close to those previously found for the mammalian GSTP1-1 isozyme. It was concluded that despite their low sequence homology (18%), GSTB1-1 and GSTP1-1 displayed similar structural features in their G-site regions and probably a common organization in structural domains.
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D005075:Biological Evolution; D002918:Chymotrypsin; D002942:Circular Dichroism; D004137:Dinitrochlorobenzene / Q000378:metabolism / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005978:Glutathione / Q000031:analogs & derivatives / Q000494:pharmacology; D005982:Glutathione Transferase / Q000737:chemistry* / Q000378:metabolism; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism; D017433:Protein Structure, Secondary; D011513:Proteus mirabilis / Q000201:enzymology*; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D014357:Trypsin
chemical_list: D004137:Dinitrochlorobenzene; D010446:Peptide Fragments; D005982:Glutathione Transferase; D002918:Chymotrypsin; D014357:Trypsin; D005978:Glutathione; C017514:S-methyl glutathione