Studies on the biochemistry and physiology of inositol phospholipids in Dunaliella salina

Thesis/Dissertation · Thu Dec 31 23:00:00 EST 1987

OSTI ID:7105637

Einspahr, K J

In the unicellular alga, Dunaliella salina, phosphatidylinositol, phosphatidylinositol 4-phosphate (PIP), and phosphatidylinositol 4,5-bisphosphate (PIP{sub 2}) comprise 14.8, 1.2, and 0.3 mol %, respectively, of cellular phospholipids. In isolated plasma membrane fractions, PIP and PIP{sub 2} are highly concentrated, together comprising 9.5 mol % of plasmalemma phospholipids. The metabolism of these inositol phospholipids and phosphatidic acid (PA) is very rapid under normal growth conditions, as illustrated by the fact that within 5 minutes after introduction of {sup 32}P{sub i} into the growth medium over 75% of lipid-bound label was found in these quantitatively minor phospholipids. Within 2 minutes after a sudden hypoosmotic shock, the levels of PIP{sub 2} and PIP dropped to 65 and 79%, respectively, of controls. Within the same time frame PA rose to 141% of control values. These data suggest that a rapid breakdown of the polyphosphoinositides may mediate the profound morphological and physiological changes which allow this organism to survive drastic hypoosmotic stress.

• Research Organization: Texas Univ., Austin, TX (USA)
• OSTI ID: 7105637
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
550501 -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALGAE
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMISTRY
BIOLOGICAL STRESS
CARBOHYDRATES
CHEMISTRY
DAYS LIVING RADIOISOTOPES
ESTERS
GROWTH
INOSITOL
INOSITOLS
ISOTOPE APPLICATIONS
ISOTOPES
LIGHT NUCLEI
LIPIDS
METABOLISM
MONOSACCHARIDES
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PHYSIOLOGY
PLANTS
RADIOISOTOPES
SACCHARIDES
TRACER TECHNIQUES