The hydrogenase enzyme catalytically converts protons to hydrogen. The hydrogenase enzyme contains a number of [Fe₄S₄] clusters that act as an electron transport chain, shuttling electrons to the active site. To replicate this, [FeFe]hydrogenase mimics featuring redox active quinone moieties annealed onto an Fe₂S₂(CO)₆ core were synthesized. EPR of these compounds revealed significant communication between the quinone ligand and the Fe₂S₂(CO)₆ core upon one electron reduction. Mimics featuring the redox active 2-phenylazopyridine ligand annealed onto [μ-1,3-propanedithiolato]bis(tricarbonyliron) and [μ-1,2-benzenedithiolato]bis (tricarbonyliron) were also synthesized. UV-Visible spectroscopy showed that metal to ligand charge transfer was occurring in these complexes The hydrogenase enzyme also contains a proton transport chain. [μ-1,2-Benzenedithiolato]bis(tricarbonyliron) complexes substituted with hydrogen donating phosphines were synthesized to mimic this. Attempts to synthesize the thiol substituted phosphine complex were unsuccessful, so protection group chemistry was employed. Electrochemistry of the resulting complexes showed an increase in catalytic current as well as a decrease in overpotential, when compared to the triphenylphosphine substituted complex. Finally, an effort to combine a redox active and hydrogen donating moiety into a single complex using substituted 2-phenylazopyradine moieties was attempted without success.

In Azotobacter chroococcum the hydrogenase gene (hup) cluster spans about 14 kb of DNA. In this study about 12 kb of the hup region beginning immediately downstream of the structural genes (hupSL) were sequenced. This revealed 14 additional open reading frames (ORFs) which we designated hupZMNOQRTVABYCDE. All of them are transcribed from the same strand as hupSL and are closely linked. The polypeptides predicted from all these genes are homologous to products of the gene clusters of membrane-bound (NiFe) hydrogenases from other bacteria, including Azotobacter vinelandii, Alcaligenes eutrophus, Rhodobacter capsulatus, Rhizobium leguminosarum and Escherichia coli. The products of hupR and hupZ may be involved in hydrogenase-linked electron transport since they are similar to rubredoxins and b-type cytochromes, respectively. / Site-directed mutagenesis of hupB, hupY, hupD and hupE abolished Hup activity with either O$ sb2$ or methylene blue as the electron acceptor whereas two insertions downstream of the hupE gene had no effect on Hup activity. A 10.5 kb fragment of DNA beginning in hupR was able to complement hupD and hupE mutants, supporting earlier evidence for a promoter downstream of hupSL. / Mutations in hupB, hupY and hupD had little effect on $ beta$-galactosidase activity in a strain also carrying a hupL-lacZ fusion, indicating that hupB, hupY and hupD are probably not involved in regulating the transcription of hupSL. / Adding nickel to the medium restored wild-type Hup activity to a hupB mutant and about half of the activity in a hupA mutant, indicating that the hupB and hupA gene products may be involved in Ni metabolism.

Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

Thesis (Ph.D.)--Cleveland State University, 2008. / Title from PDF t.p. (viewed on Apr. 6, 2009). Abstract. Includes bibliographical references (p. 99-109). Available online via the OhioLINK ETD Center. Also available in print.

Thesis (Ph.D.)--Cleveland State University, 2008. / Abstract. Title from PDF t.p. (viewed on Apr. 13, 2009). Includes bibliographical references (p. 102-109). Available online via the OhioLINK ETD Center. Also available in print.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1952. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Bibliography: leaves 112-119.

Thesis (Ph. D.)--University of Wisconsin, 1964. / Typescript. Vita. Bibliography: leaves 125-139.

Berlin, Univ., Diss., 2001. / Computerdatei im Fernzugriff.

Berlin, Univ., Diss., 2001. / Computerdatei im Fernzugriff.