Functional insights from the structural modelling of a small Fe-hydrogenase.
Recently, a novel Fe-hydrogenase from a high rate of hydrogen producing Enterobacter cloacae strain IIT-BT08 was identified and partially characterized. This 147 residue protein was found to be much smaller than previously known Fe-hydrogenases, yet retaining a high catalytic activity. We predicted the structure of this protein and found it to be structurally similar to one of the two sub-domains containing the catalytic H-cluster so far jointly present in all other Fe-hydrogenases. This novel architecture allows a tentative explanation of protein function with the high rate of catalytic activity being due to a missing regulatory sub-domain, presumably allowing higher enzymatic activity at the cost of greater exposure to oxygen inactivation. This new insight may improve our understanding of the molecular and functional organization of other, more complex Fe-hydrogenases.
Tosatto
Silvio C E
SC
Department of Biology, University of Padova, Viale G.Colombo 3, 35131 Padova, Italy.
Giacometti
Giorgio M
GM
Valle
Giorgio
G
Costantini
Paola
P
D000595:Amino Acid Sequence; D020134:Catalytic Domain; D019295:Computational Biology; D003198:Computer Simulation; D016972:Enterobacter cloacae / Q000201:enzymology*; D006864:Hydrogenase / Q000737:chemistry*; D007506:Iron-Sulfur Proteins / Q000737:chemistry*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
D007506:Iron-Sulfur Proteins; C118830:iron hydrogenase; D006864:Hydrogenase