Characterization of the active site of a hydrogen sensor from Alcaligenes eutrophus

FEBS Letters

Lenz, Oliver²  Albracht, Simon P.J¹  Friedrich, Bärbel²  Pierik, Antonio J¹  Schmelz, Milena² 

[1] E.C. Slater Institute, Biochemistry, University of Amsterdam, Plantage Muidergracht 12, NL-1018 TV Amsterdam, The Netherlands;Institut für Biologie/Mikrobiologie, Humboldt-Universität zu Berlin, Chausseestrasse 117, D-10115 Berlin, Germany

关键词: Hydrogen;    Sensor;    Active site;    Hydrogenase;    Electron paramagnetic resonance;    Fourier transform infrared spectroscopy;    SH;    soluble (cytoplasmic) hydrogenase;    MBH;    membrane-bound hydrogenase;    RH;    regulatory hydrogenase from A. eutrophus;    RH+;    cells deficient in both the SH and the MBH;    in which the RH was overproduced from the vector pGE378;    RH−;    cells deficient in both the SH and the MBH;    containing the vector control pEDY309;   

DOI  :  10.1016/S0014-5793(98)01306-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A third hydrogenase was recently identified in the proteobacterium Alcaligenes eutrophus as a constituent of a novel H₂-sensing multicomponent regulatory system. This regulatory hydrogenase (RH) has been overexpressed in cells deficient in both the NAD⁺-reducing [NiFe]-hydrogenase and the membrane-bound [NiFe]-hydrogenase. EPR, FTIR and activity studies of membrane-free extracts revealed that the RH has an active site much like that of standard [NiFe]-hydrogenases, i.e. a Ni-Fe site with two CN⁻ groups and one CO molecule. Its catalytic power is low, but the RH is always active, insensitive to oxygen, and occurs in only two redox states.

【 授权许可】

Unknown