title: Transglutaminase-catalysed incorporation of putrescine into denatured cytochrome. Preparation of a mono-substituted derivative reactive with cytochrome c oxidase.
abstract: Guinea pig liver transglutaminase has been used to incorporate putrescine into horse heart cytochrome c. The native protein showed essentially no incorporation, while ethanol-denatured cytochrome c incorporated almost 1 mol putrescine per mol protein. No increase in this level of modification was obtained when maleylated cytochrome c and the tryptic peptides of cytochrome c were used as substrates. Analysis of the modified ethanol-denatured cytochrome c by tryptic cleavage and peptide isolation showed that glutamine-42 of the intact protein is the site of incorporation of radioactively labelled putrescine. Ethanol-denatured cytochrome c that was specifically modified at glutamine-42 by incorporated of putrescine could be readily renatured. The renatured modified protein showed reactivity with cytochrome c oxidase comparable to that of the original native protein.
mesh_terms: D000818:Animals; D002850:Chromatography, Gel; D003574:Cytochrome c Group / Q000378:metabolism*; D003576:Electron Transport Complex IV / Q000378:metabolism*; D000431:Ethanol; D005973:Glutamine / Q000378:metabolism; D006168:Guinea Pigs; D007700:Kinetics; D008099:Liver / Q000201:enzymology; D011489:Protein Denaturation; D011700:Putrescine / Q000378:metabolism*; D014357:Trypsin; D005723:gamma-Glutamyltransferase / Q000378:metabolism*
chemical_list: D003574:Cytochrome c Group; D005973:Glutamine; D000431:Ethanol; D003576:Electron Transport Complex IV; D005723:gamma-Glutamyltransferase; D014357:Trypsin; D011700:Putrescine