Mutation of Lys‐120 and Lys‐134 drastically reduces the catalytic rate of Cu,Zn superoxide dismutase

FEBS Letters

Battistoni, Andrea¹  Rotilio, Giuseppe¹  Bottaro, Grazia¹  Desideri, Alessandro²  Carri, Maria Teresa¹  O'Neill, Peter³  Polticelli, Fabio³ 

[1] Department of Biology, University of Rome ‘Tor Vergata’, Via della Ricerca Scientifica, 00133 Rome, Italy;Department of Organic and Biological Chemistry, University of Messina, Salita Sperone, 98100 Messina, Italy;MRC, Radiobiology Unit, Chilton, Didcot, Oxon OX11 0RD, UK

关键词: Superoxide dismutase;    Site-directed mutagenesis;    Pulse radiolysis;    Brownian dynamics;    Electrostatic interaction;   

DOI  :  10.1016/0014-5793(94)00885-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Lys-120 and Lys-134, located at the edge of the active site channel in most Cu,Zn superoxide dismutases, have been suggested to play a major role in steering the anionic substrate towards the catalytic copper ion. In this study, mutants of Xenopus laevis Cu,Zn superoxide dismutase have been engineered, with Lys-120 and Lys-134 changed into leucine and threonine, respectively, and their catalytic properties have been investigated by pulse radiolysis. Results obtained demonstrate that both residues decrease the catalytic rate by about 40%, in partial disagreement with previous brownian dynamics calculations, carried out on bovine Cu,Zn superoxide dismutase.

【 授权许可】

Unknown