Inactivation of cellular caspases by peptide‐derived tryptophan and tyrosine peroxides

FEBS Letters

Hampton, Mark B¹  Morgan, Philip E²  Davies, Michael J² 

[1] Free Radical Research Group, Department of Pathology, Christchurch School of Medicine and Health Sciences, Christchurch, New Zealand;Free Radical Group, The Heart Research Institute, 145 Missenden Road, Camperdown, Sydney, NSW 2050, Australia

关键词: Caspase;    Peroxide;    Protein oxidation;    Apoptosis;    Singlet oxygen;    Photo-oxidation;    AMC;    7-amino-4-methylcoumarin;    DTT;    dithiothreitol;    GAPDH;    glyceraldehyde-3-phosphate dehydrogenase;    1O2;    singlet oxygen;   

DOI  :  10.1016/S0014-5793(02)03240-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Peroxides generated on peptides and proteins within cells, as a result of radical attack or reaction with singlet oxygen, are longer-lived than H₂O₂ due to their poor removal by protective enzymes. These peroxides readily oxidize cysteine residues and can inactivate thiol-dependent enzymes. We show here that Trp- and Tyr-derived peptide peroxides, generated by singlet oxygen, inhibit caspase activity in the lysates of apoptotic Jurkat cells. N-Ac-Trp-OMe peroxide was the most effective inhibitor, and was 30-fold more effective than H₂O₂ under identical conditions. As such, protein peroxides could modulate the progression of apoptosis in cells in which they are generated.

【 授权许可】

Unknown