Temperature endopeptidases

Lipinska, B., Zylicz, M., and Georgopoulos, C. The Htra (Degp) Protein, Essential For Escherichia-Coli Survival At High-Temperatures, Is an Endopeptidase. /. Bacteriol. 1990, 172, 1791-1797. 

The bitterness of hydrolysates can be reduced considerably by the plastein reaction. Under certain conditions (temperature, pH, peptidase concentration and other factors) proteases (such as endopeptidases) can synthesise new larger peptides from undesirable bitter peptides these larger peptides are known as plasteins and are not bitter. The plastein reaction involves a transpeptidation and/or condensation mechanism. The plastein synthesis can also... 

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