Journal Article

Isolation of a Novel NAD(P)H-Quinone Oxidoreductase from the Cyanobacterium <i>Synechocystis</i> PCC6803

Michinori Matsuo, Tsuyoshi Endo and Kozi Asada

in Plant and Cell Physiology

Published on behalf of Japanese Society of Plant Physiologists

Volume 39, issue 7, pages 751-755
Published in print July 1998 | ISSN: 0032-0781
Published online July 1998 | e-ISSN: 1471-9053 | DOI: http://dx.doi.org/10.1093/oxfordjournals.pcp.a029430
Isolation of a Novel NAD(P)H-Quinone Oxidoreductase from the Cyanobacterium Synechocystis PCC6803

More Like This

Show all results sharing these subjects:

  • Biochemistry
  • Molecular and Cell Biology
  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

A novel NAD(P)H-quinone oxidoreductase (NQR) was isolated from the cyanobacterium Synechocystis PCC6803 by ion-exchange, affinity and gel-filtration chro-matographies. Isolated NQR was found to be a drgA gene product that was a homodimer composed of 23-kDa sub-units. It showed NAD(P)H-plastoquinone oxidoreductase activity with Km values for NADPH and NADH of 12 and 48 μM respectively. The activity was inhibited by thiol-modifying reagents, but not by rotenone, amobarbital, salicylhydroxamic acid, dicumarol, flavone, or diphenylene-iodonium chloride. Therefore, the Cys-147 residue is probably involved in the catalytic reaction. The amino acid sequence of the purified NQR had some homology with those of NADH oxidase, NAD(P)H-flavin oxidoreductase, and nitroreductase but did not contain either an adenine-bind-ing motif or a phosphate-binding motif, thus, it is a new type of NQR.

Keywords: drgA; NAD(P)H-quinone oxidoreductase (NQR, EC 1.6.99.2); Respiratory electron transport; Synechocystis PCC6803

Journal Article.  0 words. 

Subjects: Biochemistry ; Molecular and Cell Biology ; Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.