Carboxypeptidase Y stability.

W S Lewis; S M Schuster

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PubMed · 1939132

Carboxypeptidase Y stability.

W S Lewis·S M Schuster

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Abstract

The stability of carboxypeptidase Y under different reaction conditions and in the presence various cosolvents was investigated. Loss of both hydrolysis and transpeptidation activities was monitored. Incubation of the enzyme at high temperatures or high pH resulted in the loss of both activities at the same rate. Addition of ammonium sulfate resulted in loss of transpeptidation activity but not hydrolysis activity. Addition of some organic solvents or Triton X-100 to the incubation mixture resulted in loss of both activities with transpeptidation being lost more rapidly than hydrolysis activity, while other organic solvents were observed to eliminate both activities entirely. Incubation of the enzyme in the presence of sodium dodecyl sulfate resulted in a decrease in both activities but hydrolysis was lost more rapidly than the transpeptidase activity. Implications of the observed preferential loss of activities to the labeling of peptides and proteins is discussed.

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Ammonium Sulfate Carboxypeptidases Detergents Hydrogen-Ion Concentration Hydrolysis In Vitro Techniques Peptidyl Transferases Protein Denaturation Solvents Temperature Time Factors Journal Article Research Support, Non-U.S. Gov't

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W S Lewis, S M Schuster. 1991-11-05. Carboxypeptidase Y stability.. https://pubmed.ncbi.nlm.nih.gov/1939132/

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