Rapidly metabolizing pool of phosphatidylglycerol as a precursor for phosphatidylethanolamine and diglyceride in Bacillus megaterium

Journal Article · Fri Feb 01 04:00:00 EST 1980 · J. Bacteriol.; (United States)

OSTI ID:5370524

Lombardi, F J; Chen, S L; Fulco, A J

Pulse-chase experiments in Bacillus megaterium ATCC 14581 with (U-/sup 14/C)-palmitate, L-(U-/sup 14/C)serine, and (U-/sup 14/C)glycerol showed that a large pool of phosphatidylglycerol (PG) which exhibited rapid turnover in the phosphate moiety (PG/sub t/) underwent very rapid interconversion with the large diglyceride (DG) pool. Kinetics of DG labeling indicated that the fatty acyl and diacylated glycerol moieties of PG/sub t/ were also utilized as precursors for net DG formation. The (U-/sup 14/C)glycerol pulse-chase results also confirmed the presence of a second, metabolically stable pool of PG (PG/sub s/), which was deduced from (/sup 32/P)phosphate studies. The other major phospholipid, phosphatidylethanolamine (PE), exhibited pronounced lags relative to PG and DG in /sup 14/C-fatty acid, (/sup 14/C)glycerol, and (/sup 32/P)-phosphate incorporation, but not for incorporation of L-(U-/sup 14/C)serine into the ethanolamine group of PE or into the serine moiety of the small phosphatidylserine (PS) pool. Furthermore, initial rates of L-(U-/sup 14/C)serine incorporation into the serine and ethanolamine moieties of PS and PE were unaffected by cerulenin. The results provided compelling in vivo evidence that de novo PG/sub t/, PS, and PE syntheses in this organism proceed for the most part sequentially in the order PG/sub t/ ..-->.. PS ..-->.. PE rather than via branching pathways from a common intermediate and that the phosphatidyl moiety in PS and PE is derived largely from the corresponding moiety in PG/sub t/, whereas the DG pool indirectly provides an additional source for this conversion by way of the facile PG/sub t/ in equilibrium DG interconversion.

• Research Organization: Univ. of California Medical School, Los Angeles
• DOE Contract Number: EY-76-C-03-0012
• OSTI ID: 5370524
• Journal Information: J. Bacteriol.; (United States), Journal Name: J. Bacteriol.; (United States) Vol. 141:2; ISSN JOBAA
• Country of Publication: United States
• Language: English

Related Subjects

550200 -- Biochemistry
550700* -- Microbiology
59 BASIC BIOLOGICAL SCIENCES
ALCOHOLS
AMINO ACIDS
BACILLUS
BACILLUS MEGATERIUM
BACTERIA
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL PATHWAYS
BIOSYNTHESIS
CARBON 14
CARBON ISOTOPES
CARBOXYLIC ACIDS
CELL CULTURES
DATA
DATA FORMS
DAYS LIVING RADIOISOTOPES
ESTERS
EVEN-EVEN NUCLEI
EXPERIMENTAL DATA
GLYCEROL
GRAPHS
HEXADECANOIC ACID
HYDROXY ACIDS
HYDROXY COMPOUNDS
INFORMATION
INHIBITION
ISOTOPES
KINETICS
LIGHT NUCLEI
LIPIDS
MEMBRANES
METABOLISM
MICROORGANISMS
MONOCARBOXYLIC ACIDS
NUCLEI
NUMERICAL DATA
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHOLIPIDS
PHOSPHORIC ACID ESTERS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
RADIOISOTOPES
REACTION KINETICS
SERINE
SYNTHESIS
TIME DEPENDENCE
YEARS LIVING RADIOISOTOPES