The role of conserved residues of chagasin in the inhibition of cysteine peptidases.
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ABSTRACT:
SUBMITTER: dos Reis FC
PROVIDER: S-EPMC2607524 | biostudies-literature | 2008 Feb
REPOSITORIES: biostudies-literature
Publications
The role of conserved residues of chagasin in the inhibition of cysteine peptidases.
dos Reis Flavia C G FC Smith Brian O BO Santos Camila C CC Costa Tatiana F R TF Scharfstein Julio J Coombs Graham H GH Mottram Jeremy C JC Lima Ana Paula C A AP
FEBS letters 20080115 4
We have evaluated the roles of key amino acids to the action of the natural inhibitor chagasin of papain-family cysteine peptidases. A W93A substitution decreased inhibitor affinity for human cathepsin L 100-fold, while substitutions of T31 resulted in 10-100-fold increases in the K(i) for cruzipain of Trypanosoma cruzi. A T31A/T32A double mutant had increased affinity for cathepsin L but not for cruzipain, while the T31-T32 deletion drastically affected inhibition of both human and parasite pep ...[more]
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