Phosphatidic acid synthesis in castor bean endosperm

Journal Article · Mon Feb 28 23:00:00 EST 1977 · Plant Physiol.; (United States)

DOI:https://doi.org/10.1104/pp.59.3.459· OSTI ID:7256604

Vick, B; Beevers, H

Enzyme assays on organelles isolated from the endosperm of castor bean (Ricinus communis var. Hale) by sucrose density gradient centrifugation showed that palmitoyl-CoA:sn-glycerol 3-phosphate acyltransferase (EC 2.3.1.15) was localized in the membranes of the endoplasmic reticulum. Mn/sup 2 +/ was required for activity, but Ca/sup 2 +/ and Mg/sup 2 +/ could substitute for Mn/sup 2 +/ at higher concentrations. The apparent Km was 170 ..mu..M for sn-glycerol 3-phosphate and approximately 8 ..mu..M for palmitoyl-CoA. The optimum pH range was 7 to 7.5 and the principal reaction product was diacyl-sn-glycerol 3-phosphate (phosphatidic acid). Monoacyl-sn-glycerol 3-phosphate (lysophosphatidic acid) was not released as a free intermediate in the reaction. The maximum activity of the enzyme occurred immediately after imbibition, preceding the development of mitochondria and glyoxysomes.

• Research Organization: Univ. of California, Santa Cruz
• OSTI ID: 7256604
• Journal Information: Plant Physiol.; (United States), Journal Name: Plant Physiol.; (United States) Vol. 59:3; ISSN PLPHA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
59 BASIC BIOLOGICAL SCIENCES
ATOMIC IONS
BIOASSAY
BIOMASS
BIOSYNTHESIS
CALCIUM IONS
CASTOR
CATALYSIS
CELL CONSTITUENTS
CHARGED PARTICLES
ENDOPLASMIC RETICULUM
ENDOSPERM
ENERGY SOURCES
ENZYMES
IONS
MAGNESIUM IONS
MANGANESE IONS
MEDICINAL PLANTS
MEMBRANES
METABOLISM
MITOCHONDRIA
ORGANOIDS
OXYGEN COMPOUNDS
PHOSPHATES
PHOSPHORUS COMPOUNDS
PLANT TISSUES
PLANTS
RENEWABLE ENERGY SOURCES
SYNTHESIS