Kinetic aspects of glucose oxidation by Gluconobacter oxydans cells immobilized in calcium alginate

1983 ◽  
Vol 17 (1) ◽  
pp. 13-18 ◽  
Author(s):  
J. Tramper ◽  
K. Ch. A. M. Luyben ◽  
W. J. J. Tweel
Keyword(s):  
Calcium Alginate ◽  
Glucose Oxidation ◽  
Gluconobacter Oxydans

Characterization of Gluconobacter oxydans immobilized in calcium alginate

1985 ◽  
Vol 22 (1) ◽  
Author(s):  
Patrick Adlercreutz ◽  
Olle Holst ◽  
Bo Mattiasson
Keyword(s):  
Calcium Alginate ◽  
Gluconobacter Oxydans

Glucose Oxidation and PQQ-Dependent Dehydrogenases in Gluconobacter oxydans

2009 ◽  
Vol 16 (1-2) ◽  
pp. 6-13 ◽  
Author(s):  
Tina Hölscher ◽  
Ute Schleyer ◽  
Marcel Merfort ◽  
Stephanie Bringer-Meyer ◽  
Helmut Görisch ◽  
...  
Keyword(s):  
Glucose Oxidation ◽  
Gluconobacter Oxydans

Plasmid-mediated direct-glucose oxidation in Gluconobacter oxydans

1989 ◽  
Vol 10 (1) ◽  
pp. 85-88 ◽  
Author(s):  
G.N. Qazi ◽  
V. Verma ◽  
R. Parshad ◽  
C.L. Chopra
Keyword(s):  
Glucose Oxidation ◽  
Gluconobacter Oxydans

scholarly journals The Auxiliary NADH Dehydrogenase Plays a Crucial Role in Redox Homeostasis of Nicotinamide Cofactors in the Absence of the Periplasmic Oxidation System in Gluconobacter oxydans NBRC3293

2020 ◽  
Vol 87 (2) ◽  
Author(s):  
Feronika Heppy Sriherfyna ◽  
Minenosuke Matsutani ◽  
Kensuke Hirano ◽  
Hisashi Koike ◽  
Naoya Kataoka ◽  
...  
Keyword(s):  
Glucose Oxidation ◽  
Nadh Dehydrogenase ◽  
Redox Homeostasis ◽  
Gluconobacter Oxydans ◽  
Wild Type ◽  
Content Type ◽  
Substrate Specificities ◽  
Cell Biomass ◽  
Oxidation Of Glucose ◽  
Oxidation System

ABSTRACT Gluconobacter oxydans has the unique property of a glucose oxidation system in the periplasmic space, where glucose is oxidized incompletely to ketogluconic acids in a nicotinamide cofactor-independent manner. Elimination of the gdhM gene for membrane-bound glucose dehydrogenase, the first enzyme for the periplasmic glucose oxidation system, induces a metabolic change whereby glucose is oxidized in the cytoplasm to acetic acid. G. oxydans strain NBRC3293 possesses two molecular species of type II NADH dehydrogenase (NDH), the primary and auxiliary NDHs that oxidize NAD(P)H by reducing ubiquinone in the cell membrane. The substrate specificities of the two NDHs are different from each other: primary NDH (p-NDH) oxidizes NADH specifically but auxiliary NDH (a-NDH) oxidizes both NADH and NADPH. We constructed G. oxydans NBRC3293 derivatives defective in the ndhA gene for a-NDH, in the gdhM gene, and in both. Our ΔgdhM derivative yielded higher cell biomass on glucose, as reported previously, but grew at a lower rate than the wild-type strain. The ΔndhA derivative showed growth behavior on glucose similar to that of the wild type. The ΔgdhM ΔndhA double mutant showed greatly delayed growth on glucose, but its cell biomass was similar to that of the ΔgdhM strain. The double mutant accumulated intracellular levels of NAD(P)H and thus shifted the redox balance to reduction. Accumulated NAD(P)H levels might repress growth on glucose by limiting oxidative metabolisms in the cytoplasm. We suggest that a-NDH plays a crucial role in redox homeostasis of nicotinamide cofactors in the absence of the periplasmic oxidation system in G. oxydans. IMPORTANCE Nicotinamide cofactors NAD+ and NADP+ mediate redox reactions in metabolism. Gluconobacter oxydans, a member of the acetic acid bacteria, oxidizes glucose incompletely in the periplasmic space—outside the cell. This incomplete oxidation of glucose is independent of nicotinamide cofactors. However, if the periplasmic oxidation of glucose is abolished, the cells oxidize glucose in the cytoplasm by reducing nicotinamide cofactors. Reduced forms of nicotinamide cofactors are reoxidized by NADH dehydrogenase (NDH) on the cell membrane. We found that two kinds of NDH in G. oxydans have different substrate specificities: the primary enzyme is NADH specific, and the auxiliary one oxidizes both NADH and NADPH. Inactivation of the latter enzyme in G. oxydans cells in which we had induced cytoplasmic glucose oxidation resulted in elevated intracellular levels of NAD(P)H, limiting cell growth on glucose. We suggest that the auxiliary enzyme is important if G. oxydans grows independently of the periplasmic oxidation system.

Sign in / Sign up

Export Citation Format

Share Document