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.
Zadvorny
O A
OA
Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Moscow Region, Russia. olegz@issp.serpukhov.su
Zorin
N A
NA
Gogotov
I N
IN
Gorlenko
V M
VM
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