Expression of guinea-pig liver transglutaminase cDNA in Escherichia coli

摘要: Transglutaminases (EC 2.3.2.13) catalyze the formation of g-(γ-glutamyl)lysine cross-links and substitution a variety primary amines for γ-carboxamide groups protein-bound glutamine residues. These enzymes are involved in many biological phenomena. Transglutaminase reactions also have been shown to be suitable applied enzymology. In this study, as first step studies elucidate structure/function relationship transglutaminase, we constructed an expression plasmid, pKTG1, containing cDNA guinea-pig liver transglutaminase between NcoI PstI sites vector, pKK233–2, produced unfused protein Escherichia coli. The purified recombinant enzyme was indistinguishable from natural some structural properties such molecular mass, amino acid composition, amino- carboxyl-terminal sequences. However, α-amino group amino-terminal alanine residue not acetylated that enzyme. Comparison with one did indicate significant differences specific activity apparent Km values substrates histamine incorporation into acetyl αs1-casein. sensitivity activation by Ca2+ rate catalyzed cross-linking were similar transglutaminases. results indicated Nα-acetyl has particular role catalytic function