Properties of stable hydrogenase from the purple sulfur bacterium Lamprobacter modestohalophilus.
Some properties of a hydrogenase from the recently isolated phototrophic sulfur bacterium Lamprobacter modestohalophilus strain Syvash and its resistance to a number of inactivating factors have been investigated. The enzyme consists of two subunits, 64 and 30 kD; pI = 4.5. The optimal pH was 8.5-9.5 for hydrogen uptake and 4.0 for H2 evolution. Hydrogenase preparations were resistant to the effects of O2, CO, and temperature, revealing high stability under storage. A considerable inactivation of the enzyme was observed at temperatures above 80 degrees C; the temperature optimum of methyl viologen reduction by H2 was 85 degrees C. Inhibitory effects of Ni2+, Cd2+, and Mg2+ on the hydrogenase activity were shown to be reversible and competitive with respect to methyl viologen in the hydrogen oxidation reaction.
Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia. olegz@issp.serpukhov.su
O A
OA
Zadvorny
N A
NA
Zorin
I N
IN
Gogotov
V M
VM
Gorlenko
D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D002248:Carbon Monoxide / Q000737:chemistry; D004795:Enzyme Stability; D006094:Gram-Positive Bacteria / Q000201:enzymology*; D006859:Hydrogen / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006864:Hydrogenase / Q000737:chemistry* / Q000302:isolation & purification; D008670:Metals / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen; D010269:Paraquat / Q000737:chemistry*; D021122:Protein Subunits / Q000737:chemistry
D001426:Bacterial Proteins; D008670:Metals; D021122:Protein Subunits; D002248:Carbon Monoxide; D006859:Hydrogen; D006864:Hydrogenase; D010269:Paraquat; D010100:Oxygen