Localization of the enzymes involved in the photoevolution of H sub 2 from acetate in Chlamydomonas reinhardtii

Journal Article · Sat Jul 01 00:00:00 EDT 1989 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.90.3.788· OSTI ID:7194707

Willeford, K O; Gibbs, M ^[1]

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1. Brandeis Univ., Waltham, MA (USA)

The localization of a series of enzymes involved in the anaerobic photodissimilation of acetate in Chlamydomonas reinhardtii F-60 adapted to a hydrogen metabolism was determined through the enzymatic analyses of the chloroplastic, cytoplasmic, and mitochondrial fractions obtained with a cellular fractionation procedure that incorporated cell wall removal by treatment with autolysine, digestion of the plasmalemma with the detergent digitonin, and fractionation by differential centrifugation on a Percoll step gradient. The sequence of events leading to the photoevolution of H{sub 2} from acetate includes the conversion of acetate into succinate via the extraplastidic glyoxylate cycle, the oxidation of succinate to fumarate by chloroplastic succinate dehydrogenase, and the oxidation of malate to oxaloacetate in the chloroplast by NAD dependent malate dehydrogenase. The level of potential activity for the enzymes assayed were sufficient to accommodate the observed rate of the photoanaerobic dissimilation of acetate and the photoevolution of H{sub 2}.

• DOE Contract Number: AC02-76ER03231
• OSTI ID: 7194707
• Journal Information: Plant Physiology; (USA), Vol. 90:3; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CHLAMYDOMONAS
ENZYME ACTIVITY
ACETATES
ANAEROBIC CONDITIONS
BIOLOGICAL PATHWAYS
CHLOROPLASTS
HYDROGEN
METABOLISM
OXIDOREDUCTASES
PHOTOCHEMICAL REACTIONS
ALGAE
CARBOXYLIC ACID SALTS
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHLOROPHYCOTA
ELEMENTS
ENZYMES
MICROORGANISMS
NONMETALS
PLANTS
UNICELLULAR ALGAE
551000* - Physiological Systems