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H R WHITELEY

Publications and source records attributed to H R WHITELEY.

14 recordsLinked to original sources
PubMed1963

Degradation of pyruvate by Micrococcus lactilyticus. III. Properties and cofactor requirements of the carbon dioxide-exchange reaction.

Whiteley, H. R. (University of Washington, Seattle) and N. G. McCormick. Degradation of pyruvate by Micrococcus lactilyticus. III. Properties and cofactor requirements of the carbon dioxide-exchange reaction. J. Bacteriol. 85:382-393. 1963.-At an acid pH, extracts of Micrococcus lactilyticus (Veillonella alcalescens) catalyze the oxidative decarboxylation of pyruvate to carbon dioxide, hydrogen, and acetyl phosphate, and the rapid exchange of carbon dioxide into the carboxyl group of pyruvate. These reactions take place only under anaerobic conditions and require phosphate (or arsenate), a reducing agent, diphosphothiamine, coenzyme A, an electron acceptor (ferredoxin, flavins, dyes, or certain inorganic anions), and a divalent cation (Co(++)> Mn(++) > Mg(++) > Fe(++)). High concentrations of coenzyme A and electron acceptors stimulate pyruvate breakdown but inhibit CO(2) exchange. Exchange is also inhibited by p-chloromercuribenzoate but not by arsenite. Extracts rapidly lose the ability to mediate the exchange reaction after passage through diethylaminoethyl- or triethylaminoethyl-cellulose or Dowex-1; this loss in activity may be prevented by adding a reducing agent and the above cofactors. The exchange of CO(2) and formate by M. lactilyticus is compared.

Carbon Dioxide↗
PubMed1962

Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements.

Woolfolk, C. A. (University of Washington, Seattle) and H. R. Whiteley. Reduction of inorganic compounds with molecular hydrogen by Micrococcus lactilyticus. I. Stoichiometry with compounds of arsenic, selenium, tellurium, transition and other elements. J. Bacteriol. 84:647-658. 1962.-Extracts of Micrococcus lactilyticus (Veillonella alcalescens) oxidize molecular hydrogen at the expense of certain compounds of arsenic, bismuth, selenium, tellurium, lead, thallium, vanadium, manganese, iron, copper, molybdenum, tungsten, osmium, ruthenium, gold, silver, and uranium, as well as molecular oxygen. Chemical and manometric data indicate that the following reductions are essentially quantitative: arsenate to arsenite, pentavalent and trivalent bismuth to the free element, selenite via elemental selenium to selenide, tellurate and tellurite to tellurium, lead dioxide and manganese dioxide to the divalent state, ferric to ferrous iron, osmium tetroxide to osmate ion, osmium dioxide and trivalent osmium to the metal, uranyl uranium to the tetravalent state, vanadate to the level of vanadyl, and polymolybdate ions to molybdenum blues with an average valence for molybdenum of +5. The results of a study of certain other hydrogenase-containing bacteria with respect to their ability to carry out some of the same reactions are also presented.

Arsenic↗
PubMed1958

Folic acid coenzymes.

The above reactions involving "active formyl" and "active hydroxymethyl" groups, their interconversion, their connections with free HCOOH and HCHO, and their interdigitation with methyl groups are diagrammed in Fig. 1.

Coenzymes↗