Open AccessOccurrence of an NADH diaphorase activity associated with xanthine dehydrogenase in Chlamydomonas reinhardtii
Author(s) -
PérezVicente Rafael,
Pineda Manuel,
Cárdenas Jacobo
Publication year - 1987
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1987.tb02166.x
Subject(s) - chlamydomonas reinhardtii , xanthine dehydrogenase , diaphorase , biochemistry , xanthine , chemistry , chlamydomonas , enzyme , biology , mutant , xanthine oxidase , gene
Wild‐type Chlamydomonas reinhardtii cells exhibited a peculiar NADH‐nitrobluetetrazolium reductase (NADH diaphorase) activity when grown under conditions in which xanthine dehydrogenase (XDH) is present. This XDH‐coinduced diaphorase was electrophoretically distinguishable from constitutive diaphorases, showed the same mobility as XDH and could be assayed in vitro with dichlorophenol indophenol. Mutant strains 102, 104 and 307 of Chlamydomonas which lack XDH did not exhibit XDH‐coinduced diaphorase. Heat treatment of crude extracts or partial purification of XDH inactivated or removed all constitutive diaphorases and left significant levels of XDH‐coinduced diaphorase which remained always associated with XDH. These results demonstrate that XDH from C. reinhardtii , like other organisms, is also capable of catalyzing NADH oxidation.