Single mutation at the intersubunit interface confers extra efficiency to Cu,Zn superoxide dismutase

FEBS Letters

Falconi, Mattia²  Stroppolo, Maria Elena²  Pesce, Alessandra¹  Desideri, Alessandro²  Bolognesi, Martino¹  O'Neill, Peter³ 

[1] INFM, Dipartimento di Fisica and Centro Biotecnologie Avanzate, Universita’ di Genova, Largo Giovanna Benzi, 16150 Genoa, Italy;INFM, Dipartimento di Biologia, Universita’ di Roma, Tor Vergata, Via della Ricerca Scientifica snc, 00133 Rome, Italy;Radiation and Genome Stability Unit, Medical Research Council, Harwell, Didcot, Oxon OX11 0RD, UK

关键词: Superoxide dismutase;    Intersubunit contact;    Extra efficient enzyme;    Dynamical property;    Cu;    Zn SOD;    Cu;    Zn superoxide dismutase;    PSOD;    Cu;    Zn superoxide dismutase from Photobacterium leiognathi;   

DOI  :  10.1016/S0014-5793(00)01967-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The Val28→Gly single mutant at the subunit interface of Cu,Zn superoxide dismutase from Photobacterium leiognathi displays a k _cat/K _M value of 1.7×10¹⁰ M⁻¹ s⁻¹, twice that of the native enzyme. Analysis of the three-dimensional structure indicates that the active site Cu,Zn center is not perturbed, slight structural deviations being only localized in proximity of the mutation site. The enzyme–substrate association rate, calculated by Brownian dynamics simulation, is identical for both enzymes, indicating that the higher catalytic efficiency of the Val28→Gly mutant is not due to a more favorable electrostatic potential distribution. This result demonstrates the occurrence of an intramolecular communication between the mutation site and the catalytic center, about 18 Å away and indicates a new strategy to encode extra efficiency within other members of this enzymatic family.

【 授权许可】

Unknown