Mutant strains of Escherichia coli which expressed different levels of hydrogenase activity when grown anaerobically under a variety of conditions were obtained by mutagenesis and selective growth and screening procedures. Four classes of mutants were isolated, ranging from those devoid of enzyme activity to those expressing maximal activity under all growth conditions. One class of mutants (A) could not grow on fumarate plus H2 in the presence of active fumarate reductase. Since hydrogenase is essential for growth under these conditions some of these strains may be hydrogenase-negative. Three other classes of mutants were isolated which were all hydrogenase-positive and fully expressed this activity when grown on fumarate plus H2. They differed in the level of expression of hydrogenase activity when grown anaerobically on glucose, conditions which do not require hydrogenase for growth. Class B mutants expressed less activity, while class C mutants expressed more activity than the parental strain. Class D mutants fully expressed hydrogenase activity and were dependent on the enzyme for growth. The different strains were also assayed for reduction of dyes by hydrogen and for evolution of hydrogen from reduced methyl viologen. Some of the hydrogenase-positive strains showed altered activities in these assays suggesting that mutations may have occurred either in enzymes or proteins required for reaction with dyes or in the hydrogenase enzyme itself.
ChippauxM., CasseF., PascalM.-C.1972; Isolation and phenotypes of mutants from Salmonella typhimurium defective in formate hydrogenlyase activity. Journal of Bacteriology 110:776–778
ChippauxM., GuidiciD., Abou-JaoudeA., CasseF., PascalM.-C.1978; A mutation leading to the total lack of nitrite reductase activity in Escherichia coli K12. Molecular and General Genetics 160:225–229
ColeJ. A., WimpennyJ.W.T.1966; The interrelationships of low redox potential cytochrome c5S2 and hydrogenase in facultative anaerobes. Biochimica et biophysica acta 128:419–425
GlickB. R., WangP. Y., SchneiderH., MartinW. G.1980; Identification and partial character-ization of an Escherichia coli mutant with altered hydrogenase activity. Canadian Journal of Biochemistry 58:361–367
GuestJ. R.1979; Anaerobic growth of Escherichia coli K12 with fumarate as terminal electron acceptor. Genetic studies with menaquinone and fluoroacetate-resistant mutants. Journal of General Microbiology 115:259–271
LambdenP. R., GuestJ. R.1976; Mutants of Escherichia coli K12 unable to use fumarate as an anaerobic electron acceptor. Journal of General Microbiology 97:145–160
Mandrand-BerthelotM.-A., WeeM.Y.K., HaddockB. A.1978; An improved method for the identification and characterization of mutants of Escherichia coli deficient in formate dehydrogenase activity. FEMS Microbiology Letters 41:37–40
PascalM.-C., CasseF., ChippauxM., LepelletierM.1975; Genetic analysis of mutants of Escherichia coli K12 and Salmonella typhimurium LT2 deficient in hydrogenase activity. Molecular and General Genetics 141:173–179
PurecL., KrasnaA. I.1967; The activation of the hydrogenase of Proteus vulgaris by visible light. Proceedings of the National Academy of Sciences of the United States of America 57:1416–1421
PurecL., KrasnaA. I., RittenbergD.1962; The inhibition of hydrogenase by carbon monoxide and the reversal of this inhibition by light. Biochemistry 1:270–275
WimpennyJ.W.T., NecklenD. K.1971; The redox environment and microbial physiology. I. The transition from anaerobiosis to aerobiosis in continuous cultures of facultative anaerobes. Biochimica et biophysica acta 253:352–359
YamamotoI., IshimotoM.1978; Hydrogen- dependent growth of Escherichia coli in anaerobic respiration and the presence of hydrogenases with different functions. Journal of Biochemistry (Tokyo): 84:673–679