Malate synthase a membrane protein
Malate synthase (MS) is generally regarded as a peripheral membrane protein, and believed by some to be ontogenetically associated with ER. However, immuno- and cyto-chemical in situ localizations show MS throughout the matrix of cotton (and cucumber) glyoxysomes, not specifically near their boundary membranes, nor in ER. Only a maximum of 50% MS can be solubilized from cotton glyoxysomes with 1% Triton X-100, 2mM Zwittergen 14, or 10mM DOC +/- salts. Cotton MS does not incorporate /sup 3/H-glucosamine in vivo, nor does it react with Con A on columns or blots. Cotton MS banded with ER in sucrose gradients (20-40%) in Tricine after 3h, but not after 22h in Tricine or Hepes, or after 3h in Hepes or K-phosphate. Collectively the authors data are inconsistent with physiologically meaningful MS-membrane associations in ER or glyoxysomes. It appears that experimentally-induced aggregates of MS migrate in ER gradients and occur in isolated glyoxysomes. These data indicate that ER is not involved in synthesis or modification of cottonseed MS prior to its import into the glyoxysomal matrix.
- Research Organization:
- Arizona State Univ., Tempe
- OSTI ID:
- 6073154
- Report Number(s):
- CONF-8707108-; TRN: 87-037216
- Journal Information:
- Plant Physiol., Suppl.; (United States), Vol. 83:4; Conference: Annual meeting of the American Society of Plant Physiologists, St. Louis, MO, USA, 19 Jul 1987
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ENDOPLASMIC RETICULUM
BIOLOGICAL FUNCTIONS
LIGASES
BIOSYNTHESIS
SUBCELLULAR DISTRIBUTION
CELL MEMBRANES
CENTRIFUGATION
COTTON PLANTS
DETERGENTS
GLUCOSAMINE
ORGANOIDS
PLANT CELLS
PROTEINS
SEDIMENTATION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ADDITIVES
AMINES
CARBOHYDRATES
CELL CONSTITUENTS
DISTRIBUTION
EMULSIFIERS
ENZYMES
FUNCTIONS
HEXOSAMINES
HEXOSES
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MEMBRANES
MONOSACCHARIDES
ORGANIC COMPOUNDS
PLANTS
SACCHARIDES
SEPARATION PROCESSES
SURFACTANTS
SYNTHESIS
WETTING AGENTS
550201* - Biochemistry- Tracer Techniques