Premium
Effect of culture conditions on the isocitrate dehydrogenase and isocitrate lyase activities in Chlamydomonas reinhardtii
Author(s) -
MartínezRivas José M.,
Vega José M.
Publication year - 1993
Publication title -
physiologia plantarum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.351
H-Index - 146
eISSN - 1399-3054
pISSN - 0031-9317
DOI - 10.1111/j.1399-3054.1993.tb01377.x
Subject(s) - isocitrate lyase , chlamydomonas reinhardtii , isocitrate dehydrogenase , idh1 , biochemistry , chlamydomonas , biology , chemistry , enzyme , glyoxylate cycle , gene , mutation , mutant
In the green alga Chlamydomonas reinhardtii , nitrogen staravation induced a reversible increase (2‐fold) in NAD‐isocitrate dehydrogenase (NAD‐IDH; EC 1.1.1.41) and NADP‐isocitrate dehydrogenase (NADP‐IDH; EC 1.1.1.42) activities. Both enzymes were not affected by the concentration of CO 2 , the dark or the nature of the nitrogen source (nitrate, nitrite, or ammonium). When cells growing autotrophically were transferred to heterotrophic conditions, a 40% reduction of the NAD‐IDH activity was detected, a 2‐fold increase of NADP‐IDH was observed and isocitrate lyase (ICL; EC 4.1.3.1) activity was induced. The replacement of autotrophic conditions led to the initial activity levels. NAD‐ and NADP‐IDH activities showed markedly different patterns of increase in synchronous cultures of this alga obtained by 12 h light/12 h dark transitions. While NAD‐IDH increased in the last 4 h of the dark period, NADP‐IDH increased during the last 4 h of the light period, remaining constant for the rest of the cycle.