The two divergent PEP-carboxylase catalytic subunits in the green microalga Chlamydomonas reinhardtii respond reversibly to inorganic-N supply and co-exist in the high-molecular-mass, hetero-oligomeric class-2 PEPC complex

Moellering E. R., Ouyang Y., Mamedov T., Chollet R.

FEBS LETTERS, cilt.581, sa.25, ss.4871-4876, 2007 (SCI-Expanded)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 581 Sayı: 25
  • Basım Tarihi: 2007
  • Doi Numarası: 10.1016/j.febslet.2007.09.015
  • Dergi Adı: FEBS LETTERS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.4871-4876
  • Anahtar Kelimeler: PEP carboxylase, green microalgae, UN-assimilation, anaplerosis, chlamydomonas reinhardtii, ALGA SELENASTRUM-MINUTUM, PHOSPHOENOLPYRUVATE CARBOXYLASE, UNRELATED POLYPEPTIDES, GEL-ELECTROPHORESIS, KINETIC-PROPERTIES, PROTEIN COMPLEXES, ISOFORMS, ENZYME, CARBON, IDENTIFICATION
  • Akdeniz Üniversitesi Adresli: Hayır

Özet

Our recent molecular studies revealed two divergent PEP-carboxylase (PEPC vertical bar Ppe vertical bar) encoding genes in the green microalga Chlantydomonas reinhardtii, CrPpc1 and CrPpc2, which are coordinately responsive to changes in inorganic-N and -C supply at the transcript level vertical bar Mamedov, T.G., Moellering, E.R. and Chollet, R. (2005) Identification and expression analysis of two inorganic C- and N-responsive genes encoding novel and distinct molecular forms of eukaryotic phosphoenolpyruvate carboxylase in the green microalga C. reinhardtii, Plant J. 42, 832-843 vertical bar. Here, we report the distribution of these two encoded catalytic subunits in the minor Class-1 and predominant Class-2 PEPC enzyme-forms, the latter of which is a novel high-molecular-mass, hetero-oligomeric complex containing both CrPpc1 (p109) and CrPpc2 (p131) polypeptides. The Class-1 enzyme, however, is a typical PEPC homotetramer comprised solely of p109. We also document that the amount of both CrPpc1/2 catalytic subunits is up-/down-regulated by varying levels of NH4+ supplied to the culture medium. (c) 2007 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.