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L M van Golde

Publications and source records attributed to L M van Golde.

At least 145 records · Page 8Linked to original sources
PubMed1976

Selective utilization of endogenous unsaturated phosphatidylcholines and diacylglycerols by cholinephosphotransferase of mouse lung microsomes.

In the presence of CMP, cholinephosphotransferase of mouse lung microsomes catalyzes the conversion of endogenous phosphatidylcholines into 1,2-diacyl-sn-glycerols and CDPcholine. 2. In this conversion cholinephosphotransferase shows a distinct preference for those molecular species of phosphatidylcholine which contain an unsaturated fatty acid. The enzyme hardly utilizes endogenous depalmitoylglycerophosphocholine as a substrate. 3. Membrane-bound 1,2-diacyl-sn-glycerols were also prepared by treatment of mouse lung microsomes with a pure phospholipase C from Bacillus cereus. These 1,2-diacyl-sn-glycerols were subsequently utilized as substrate by cholinephosphotransferase in the formation of phosphatidylcholine. In the latter reaction, cholinephosphotransferase exhibited a pronounced preference for unsaturated 1,2-diacyl-sn-glycerols and hardly utilized the endogenous 1,2-depalmitoyl-sn-glycerol. 4. The low affinity of cholinephosphotransferase for either dipalmitoylglycerophosphocholine or 1,2-dip

Animals↗
PubMed1976

Activity of cholinephosphotransferase, lysolecithin: lysolecithin acyltransferase and lysolecithin acyltransferase in the developing mouse lung.

1. The present study presents the activity profiles of cholinephosphotransferase, lysolecithin:lysolecithin acyltransferase and lysolecithin acyltransferase at different stages of development of the mouse lung. 2. The specific activity of cholinephosphotransferase, a key enzyme in the de novo synthesis of phosphatidylcholine, increases during the later stages of fetal development until it reaches a maximal value at a gestational age of 17 days, i.e. 2 days before term. Thereafter, the activity of the enzyme declines again until around term. 2. The specific activity of lysolecithin:lysolecithin acyltransferase which catalyzes the transesterification between two molecules of 1-acyl-sn-glycero-3-phosphocholine, appears to be much lower than that of cholinephosphotransferase at gestational ages below 18 days. However, around day 18, the specific activity of lysolecithin:lysolecithin acyltransferase increases dramatically until it almost equals the maximal activity of cholinephosphotransferase measured on day 17. 4. The specific activity of lysolecithin acyltransferase, which catalyzes the direct acylation of 1-acyl-sn-glycero-3-phosphocholine, does not change significantly during the prenatal development and is lower than that of either lysolecithin:lysolecithin acyltransferase or cholinephosphotransferase at all stages of development. 5. These results are discussed in view of the possible role of these enzymes in the biosynthesis of pulmonary 1,2-dipalmitoyl-sn-glycero-3-phosphocholine.

1-Acylglycerophosphocholine O-Acyltransferase↗
PubMed1975

Lipid-phase transitions of the strictly anaerobic bacteria Veillonella parvula and Anaerovibrio lipolytica.

As a basis for physicochemical studies on the membranes of the strictly anaerobic bacteria Veillonella parvula, Anaerovibrio lipolytica, and Megasphaera elsdenii, the fatty acyl and alk-1-enyl moieties on the phosphoglycerides of these organism were characterized. Uncommon is the high proportion of a heptadecenoic acyl and alk-1-enyl moiety in these three lactate-fermenting bacteria. In contrast to V. parvula and A. lipolytica, M. elsdenii contains high amounts of branched-chain acyl and alk-1-enyl moieties. Freeze-etching electron microscopy showed that the lipids of the plasma membranes of V. parvula and A. lipolytica go from the liquid crystalline to the gel state upon lowering of the temperature, indicating that the membrane lipids are predominantly in the fluid state. No lipid-protein segregation could be detected in the plasma membrane of M. elsdenii. This can be explained by the abundance of branched-chain fatty acyl and alk-1-enyl residues in the membranes of this organism which may prevent lipid-protein segregation during the lipid-phase transition.

Anaerobiosis↗
PubMed1973

Metabolism of membrane phospholipids and its relation to a novel class of oligosaccharides in Escherichia coli.

Phosphatidylethanolamine is metabolically stable in exponentially growing cells of Escherichia coli, whereas phosphatidylglycerol and cardiolipin (diphosphatidylglycerol), labeled by growth in the presence of sn-[2-(3)H]glycero-3-(32)P, lose their radioactivity during subsequent growth on unlabeled medium. We have found that the loss of label from the lipid fraction is accompanied by its appearance in a novel type of cell constituent of E. coli, a closely related group of oligosaccharides, each containing glycerol and phosphoric acid in equimolar proportions, probably derived as intact glycerophosphate units from phosphatidylglycerol and/or cardiolipin. Glucose is the sole detectable sugar. The glycerophosphate-containing oligosaccharides may be fractionated by ion-exchange chromatography into several subfractions, some of which contain succinic acid in ester linkage. Although apparently derived from membrane phospholipids, the newly discovered substances contain no fatty acids, are soluble in water, and are insoluble in organic solvents such as chloroform. They comprise about 0.5-1% of the dry weight of growing cells.

Cardiolipins↗