Pressure Inactivation Kinetics of Microbial Transglutaminase from <i>Streptoverticillium mobaraense</i>

Abstract

ABSTRACT: Microbial transglutaminase (MTGase) forms nondisulfide covalent crosslinks in proteins. Changes in activity of MTGase from Streptoverticillium mobaraense after exposure to pressure (100 to 600 MPa for 10 to 60 min, respectively) were analyzed. MTGase activity increased linearly with enzyme concentration, regardless of pressures in the range examined. The Vmax value was changed by pressure while the Km value was independent of pressure. Sodium chloride (0 to 0.86 N) apparently caused MTGase destabilization under pressure. Oscillatory pressurization (400 to 600 MPa, 25°C, 10 min/cycle, 0 to 5 cycles) resulted in a higher degree of inactivation when pressures were greater than 500 MPa. MTGase maintained 60% of its initial activity even after pressurization at 600 MPa for 60 min, indicating that MTGase was pressure‐resistant as compared to other enzymes.