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. 1992 Aug;174(16):5295–5301. doi: 10.1128/jb.174.16.5295-5301.1992

The hoxZ gene of the Azotobacter vinelandii hydrogenase operon is required for activation of hydrogenase.

L A Sayavedra-Soto 1, D J Arp 1
PMCID: PMC206365  PMID: 1644756

Abstract

The roles of the product of the hoxZ gene immediately downstream of the hydrogenase gene (hoxKG) in Azotobacter vinelandii were investigated by constructing and characterizing a mutant with the center of the hoxZ gene deleted. The strain lacking the functional hoxZ gene product exhibited a low rate of H2 oxidation with O2 as the electron acceptor relative to that of the wild-type strain. Nevertheless, when the enzyme was exogenously activated and methylene blue was used as the electron acceptor from hydrogenase, rates of H2 oxidation comparable to those in the wild-type strain were observed. These results suggest that the gene product of hoxZ plays a role in activating and maintaining hydrogenase in a reduced active state. The product of hoxZ could also be the linkage necessary for transfer of electrons from H2 to the electron transport chain.

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Selected References

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