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1.
The phospholipids of Methylococcus capsulatus, Methylosinus trichosporium, La Paz, and OBT were examined in relation to their qualitative and quantitative composition. M. capsulatus exhibited a phospholipid composition consisting of phosphatidylethanolamine, phosphatidylglycerol, cardiolipin, and phosphatidyl-choline. The esterified fatty acids were predominantly C16:0 and C16:1. M. trichosporium, La Paz, and OBT exhibited an essentially identical phospholipid composition consisting of phosphatidylmonomethylethanolamine, phosphatidyl-dimethylethanolamine, phosphatidylcholine, and phosphatidylglycerol. Only trace amounts (less than 1%) of cardiolipin were found in these organisms. The major esterified fatty acid in these organisms was C18:1 (87 to 90%). The monounsaturated fatty acids from all four organisms consisted of both cis and trans isomers, each of which contained delta8, delta9, delta10, and delta11 double-bond positional isomers.  相似文献   

2.
The galactolipid, phospholipid, and fatty acid composition of chloroplast envelope membrane fractions isolated from leaves of Vicia faba L. has been determined. The major lipids in this fraction are: monogalactosyldiglyceride, 29%; digalactosyldiglyceride, 32%; phosphatidylcholine, 30%; and phosphatidylglycerol 9%. The lipid composition of the chloroplast envelope membranes is qualitatively similar to that of the lamellar membranes isolated from the same plastids, but the proportion of each lipid present is very different. The total galactolipid to total phospholipid ratio was 1.6: 1 in the envelope and 11.1: 1 in the lamellae. The monogalactosyldiglyceride-digalactosyl-diglyceride ratio was 0.9: 1 in the envelope and 2.4: 1 in the lamellae. Both membranes lack phosphatidylethanolamine.  相似文献   

3.
Phospholipids and fatty acids of Neisseria gonorrhoeae.   总被引:9,自引:4,他引:5       下载免费PDF全文
The phospholipids and fatty acids of two strains of Neisseria gonorrhoeae of different penicillin susceptibilities were examined. The phospholipids, which comprise about 8% of the dry weight of the cells, consisted of phosphatidylethanolamine (70%) and phosphatidylglycerol (20%); small amounts of phosphatidylcholine and traces of cardiolipin were also present. Growing and stationary-phase cells were similar in content and composition of phospholipids except for phosphatidylcholine, which increased two- to fivefold in the stationary-phase cells. The fatty acids of the phospholipids were characterized by two major acids, palmitic and a C16:1, with myristic and a C18:1 acid present in smaller amounts. The fatty acids present in purified phospholipid fractions varied considerably in relative proportions from fraction to fraction. No significant difference in the composition of phospholipids from the two strains was evident. Large amounts of beta-hydroxy lauric acid were detected only after saponification of the organisms. Differences in the lipid composition between the gonococcus and other gram-negative bacteria are discussed.  相似文献   

4.
Lipid analysis of immature pig oocytes   总被引:3,自引:0,他引:3  
The detailed analysis of the lipid composition of immature pig oocytes represents the first such study carried out on mammalian eggs. In order to undertake a large scale lipid analysis using conventional extraction and chromatographic techniques a procedure for mass harvesting relatively large numbers of pig oocytes (200-300 oocytes/ovary) was developed. The study revealed that triacylglycerol was the major lipid component (100.71 nmol/mg protein) followed by cholesterol (32.71 nmol/mg protein). Phosphatidylcholine constituted the major phospholipid component (27.83 nmol/mg protein). Pig oocytes contained relatively low proportions of phosphatidylethanolamine (16.41% total phospholipid) and relatively high proportions of lysophosphatidylcholine (4.68% total phospholipid). The free fatty acid pattern was strikingly similar to the fatty acid composition of phosphatidylcholine. This observation, in conjunction with the observed high levels of lysophosphatidylcholine and the low ratio of phosphatidylethanolamine to phosphatidylcholine, suggests a fast rate of phospholipid turnover in the immature pig oocyte. Analysis of fatty acids esterified to the individual phospholipids and neutral lipids has shown that in all the classes examined, particularly in the neutral lipid fractions, there are high levels of the saturated fatty acid palmitic acid (16:0) and the monounsaturated fatty acid oleic acid (18:1). Triacylglycerol, free fatty acids and most of the phospholipids, particularly phosphatidylethanolamine, are considerably enriched in n-6 polyunsaturated fatty acids, specifically linoleic (18:2), arachidonic (20:4) and adrenic (22:4) acids. This may indicate an ability of oocytes to synthesize prostaglandins and leukotrienes. The results show that the lipid environment of the immature pig oocyte may be adapted to the highly specialized requirements of the cell, promoting growth and development with a potential role in the regulation of maturation.  相似文献   

5.
The free fatty acid and phospholipid composition of 4 psychrophilic marineVibrio spp. have been determined in chemostat culture with glucose as the limiting substrate over a temperature range 0–20°C. All the isolates show maximum glucose and lactose uptake at 0°C and this correlates with maximum cell yield. None of the isolates contain fatty acids with a chain length exceeding 17 carbon atoms.Vibrio AF-1 andVibrio AM-1 respond to decreased growth temperatures by synthesizing increased proportions of unsaturated fatty acids (C15:1, C16:1 and C17:1) whereas inVibrio BM-2 the fatty acids undergo chain length shortening. The fourth isolate (Vibrio BM-4) contains high levels (60%) of hexadecenoic acid at all growth temperatures and the fatty acid composition changes little with decreasing temperature. The principal phospholipid components of the four psychrophilic vibrios were phosphatidylserine, phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. Lyso-phosphatidylethanolamine and 2 unknown phospholipids were additionally found inVibrio AF-1. The most profound effect of temperature on the phospholipid composition of these organisms was the marked increase in the total quantities synthesized at 0°C. At 15°C phosphatidylglycerol accumulated in the isolates as diphosphatidylglycerol levels decreased. Additionally inVibrio BM-2 andVibro BM-4 phosphatidylserine accumulates as phosphatidylethanolamine biosynthesis was similarly impaired. The observed changes in fatty acid and phospholipid composition in these organisms at 0°C may explain how solute transport is maintained at low temperature.Abbreviations PS Phosphatidylserine - PE phosphatidylethanolamine - PG phosphatidylglycerol - DPG diphosphatidylglycerol - lyso PE lysophosphatidylethanolamine  相似文献   

6.
Qualitative and quantitative profiles of phospholipids, neutral lipids, and fatty acid composition in Cr. neoformans during the growth phase were investigated in relation to pyrophosphatidic acid. A marked increase of the total lipid content, which depended on the accumulation of triglyceride in yeast cells with the growth, was observed. The total phospholipid contents in yeast cells remained almostly constant during the exponential phase and slightly decreased in the stationary phase. The major phospholipids of this yeast were phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, and cardiolipin, the next groups being pyrophosphatidic acid, phosphatidic acid, lysophos-phatidylcholine, and unidentified components. The amounts of phosphatidylcholine, phosphatidylinositol, and cardiolipin were fairly constant throughout the growth phase, but the amount of phosphatidylethanolamine increased and that of phosphatidylserine decreased with progressive growth. The pyrophosphatidic acid contents were 0.9~0.7% for total phospholipid during the growth phase. The major fatty acids of pyrophosphatidic acid were C16:0, C18:1, and C18:2 acids. The changing patterns of fatty acid composition in pyrophosphatidic acid through the growth phase closely resembled that of phosphatidic acid, which contained larger amounts of C18:1 acid (35~45%) than C16:0 acid (30~25%) and C18:2 acid (30~25%). Phosphatidylserine and phosphatidylinositol contained considerable amounts of saturated fatty acid (C16:0 acid, more than 55%). On the other hand, phosphatidylcholine, phosphatidylethanolamine, and cardiolipin contained extremely large amounts of unsaturated fatty acid (C18:1 and C18:2 acid, 85ç90%).  相似文献   

7.
Isolated hepatocytes in suspension or in primary culture were incubated with different phospholipid bases and the effects on the synthesis and composition of phospholipids were studied. After incubation in the presence of 1 mM diethylethanolamine for three days, an unnatural phospholipid, phosphatidyl-diethylethanolamine, constituted more than 20% of total phospholipids. Its fatty acid composition differed from that of other phospholipids. Incubation of hepatocytes with ethanolamine gave smaller effects and in this case the increased synthesis of phosphatidylethanolamine was compensated for by methylation to phosphatidylcholine. This system can be used for studies on the functional significance of phospholipid polar headgroups in a specialized type of cell.  相似文献   

8.
The phospholipid composition of Rhodopseudomonas acidophila strain 10050 grown aerobically or anaerobically in the light was determined. The major phospholipids present in the aerobic cells were phosphatidylethanolamine (PE; 54%), phosphatidylglycerol (PG; 24%) and cardiolipin (diphosphatidylglycerol, DPG) (14%), together with phosphatidylcholine (PC; 5%). On moving the cells to anaerobic photosynthetic growth in the light PE remained the major phospholipid (37-49%), but there was a major change in the proportion of PC, which increased to 31-33%, and corresponding reductions in the contents of PG to 11-16% and DPG to 4-5%. The fatty acid composition of the phospholipids was unusual, compared with other purple non-sulfur photosynthetic bacteria, in that it contained 16:0 (29%), 17:1 (20%) and 19:1 (9%) plus several mainly unsaturated 2-OH fatty acids (9% total) as major components, when grown aerobically in the dark. In contrast when grown photosynthetically under anaerobic conditions there was <2% 17:1 or 19:1 present, while the amounts of 16:1 and 18:1 increased, and 16:0 decreased. The phospholipid composition of the purified light-harvesting complex 2 (LH2) complex was PE (43%), PC (42%) and DPG (15%). Unexpectedly, there was no PG associated with the purified LH2. These findings contrast with previous studies on several other photosynthetic bacteria, which had shown an increase in PG upon photosynthetic growth [Biochem. J. 181 (1979) 339]. The prior hypothesis that phosphatidylglycerol has some specific role to play in the function of light-harvesting complexes cannot be true for Rps. acidophila. It is suggested that specific integral membrane proteins may strongly influence the phospholipid content of the host membranes into which they are inserted.  相似文献   

9.
The phospholipid composition and fatty acid composition of the individual phospholipids were determined in erythrocyte membrane of wild Japanese serow, Capricornis crispus, and compared with those of Japanese cattle. Sphingomyelin (SM) contributed more than 50% to the total phospholipids, with only 3% phosphatidylcholine, 30% phosphatidylethanolamine and 11% phosphatidylserine. This phospholipid composition and ratio of phospholipid to protein in erythrocyte membrane of wild serow were quite similar to those of Japanese cattle. However, marked differences in fatty acid composition were found, especially in lignoceric acid 24:0 and nervonic acid 24:1 of sphingomyelin which were major constituents (approximately 60%) of that phospholipid.  相似文献   

10.
Summary The composition of phospholipids and phospholipid fatty acids in isolated rat serous fluid mast cells was analyzed by thin layer chromatography, gas-liquid chromatography and mass spectrometry. The phospholipids constituted about 50% of the mast cell lipids and phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, phosphatidylcholine, sphingomyelin and lysophosphatidylcholine were identified. The phosphatidylethanolamine fraction contained aldehydes and the highest proportion of unsaturated fatty acids. Sphingomyelin contained predominantly saturated fatty acids whereas the ratio unsaturated fatty acids: saturated fatty acids for the other phospholipids was more close to 1.  相似文献   

11.
The principal lipids associated with the electron transport membrane of Haemophilus parainfluenzae are phosphatidylethanolamine (78%), phosphatidylmonomethylethanolamine (0.4%), phosphatidylglycerol (18%), phosphatidylcholine (0.4%), phosphatidylserine (0.4%), phosphatidic acid (0.2%), and cardiolipin (3.0%). Phospholipids account for 98.4% of the extractible fatty acids. There are no glycolipids, plasmalogens, alkyl ethers, or lipo amino acid esters in the membrane lipids. Glycerol phosphate esters derived from the phospholipids by mild alkaline methanolysis were identified by their staining reactions, mobility on paper and ion-exchange column chromatography, and by the molar glycerol to phosphate ratios. Eleven diacyl phospholipids can be separated by two-dimensional thin-layer chromatography. Each lipid served as a substrate for phospholipase D, and had a fatty acid to phosphate ratio of 2:1. Each separated diacyl phospholipid was deacylated and the glycerol phosphate ester was identified by paper chromatography in four solvent systems. Of the 11 separated phospholipids, 3 were phosphatidylethanolamines, 2 were phosphatidylserines, and 2 were phosphatidylglycerols. Phosphatidylcholine, cardiolipin, and phosphatidic acid were found at a single location. Phosphatidylmonomethylethanolamine was found with the major phosphatidylethanolamine. Three distinct classes of phospholipids are separable according to their relative fatty acid compositions. (i) The trace lipids consist of two phosphatidylethanolamines, two phosphatidylserines, phosphatidylcholine, phosphatidic acid, and a phosphatidylglycerol. Each lipid represents less than 0.3% of the total lipid phosphate. These lipids are characterized by high proportions of the short (C(10) to C(14)) and long (C(19) to C(22)) fatty acids with practically no palmitoleic acid. (ii) The major phospholipids (93% of the lipid phosphate) are phosphatidylethanolamine, phosphatidylmonomethylethanolamine, and phosphatidylglycerol. These lipids contain a low proportion of the short (C(19)) fatty acids. Palmitic and palmitoleic acids represent over 80% of the total fatty acids. (iii) The fatty acid composition of the cardiolipin is intermediate between the other two classes. Both palmitoleic and the longer fatty acids represent a significant proportion of the total fatty acid.  相似文献   

12.
The lipid composition of Sendai virus, propagated in chicken eggs, was analyzed by high performance liquid chromatography (HPLC), thin-layer chromatography (TLC), and gas-liquid chromatography (GLC). Phosphatidylcholine was found to be the dominant phospholipid (37.3%) with phosphatidylethanolamine (26.8%) and phosphatidylserine (12.0%) also present in significant amounts. Analysis of the fatty acid methyl esters revealed that the dominant fatty acids in total phospholipid were: C16:0 (17.6%), C18:0 (15.4%), C18:1 (n-9) (22.0%), and C24:0 (6.0%). Cardiolipin, phosphatidylserine, and sphingomyelin contained higher levels of saturated fatty acids relative to phosphatidylinositol, phosphatidylethanolamine, and phosphatidylcholine.  相似文献   

13.
A study was carried out to determine the lipid composition of the blood-stream form of the African trypanosome. Trypanosoma vivax. Data from thin layer chromatography showed that the major polar lipids were lysophosphatidylcholine, sphingomyelin, phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and diphosphatidylglycerol. The major neutral lipids were sterol, monoacylglycerol, diacylglycerol, free fatty acid and triacyglycerol. 16:0, 18:0, 18:1 and 18:2 constituted the major fatty acids of both the polar and neutral lipid fractions. The work constituted the first detailed study on the fatty acid composition of this African trypanosome.  相似文献   

14.
The free fatty acid and phospholipid composition of 5 psychrotrophic marine Pseudomonas spp. have been determined in chemostat culture with glucose as the limiting substrate over the range 0–20°C. The predominant fatty acid present in all the isolates was hexadecenoic acid (C16:1) together with lesser quantities of octadecenoic acid (C 18:1) whilst none contained acids with chain lengths exceeding 18 carbon atoms. Decreasing the growth temperature from 20°C to 0°C resulted in little significant change in fatty acid composition. The principal phospholipid components of the five psychrotrophic pseudomonads have been identified as phosphatidylserine, phosphatidylglycerol, phosphatidylethanolamine and diphosphatidylglycerol. Decreasing the growth temperature did not elicit significant changes either in the total quantities of phospholipid synthesized or in the concentration of individual phospholipid components in any of the isolates. All the psychrotrophs showed maximum glucose uptake between 15°C and 20°C and the rate decreased rapidly as the temperature was decreased towards 0°C.Abbreviations PS Phosphatidylserine - PE phosphatidylethanolamine - PG phosphatidylglycerol - DPG diphosphatidylglycerol  相似文献   

15.
The utilization of n-hexadecane by Candida lipolytica (stain 10) was studied with respect to the lipid content, phospholipid and fatty acid profiles resulting at various growth times. Thin layer chromatography of the lipid extracts showed quantitative changes in the different lipid classes. The phospholipid fraction obtained at each growth time was separated into 8 classes: lysophosphatidylcholine, sphingomyelin, phosphatidylcholine, phosphatidylethanolamine, glycophospholipid, phosphatidylglycerol, cardiolopin, and phosphatidic acid. Differences in the percentage fatty acid composition of the lipid extracts were observed at various stages of growth. The cellular fatty acids included palmitic, palmitoleic (35-52%), stearic, oleic, linoleic (26-39%), and pentadecanoic (2-12%) as major components. This indicates that fatty acid(s) of the same length as that of the substrate was the most abundant component, thus showing intact incorporation mechaism. Fatty acids having longer chain lengths were also formed in substantial amounts indicating C2 addition and beta-oxidation of the fatty acids formed in the yeast.  相似文献   

16.
A barotolerant member of the genus Pseudomonas was isolated from deep-sea sediment obtained from the Japan Trench, at a depth of 4418 m. The growth temperature was found to affect the hydrostatic pressure range in which the bacterium could grow; the optimum hydrostatic pressure for growth shifted to a higher pressure with increasing temperature. We examined the lipid composition of the inner membrane of cells grown at various hydrostatic pressures and temperatures. The fatty acid components of the inner membrane lipids were C16:0, C16:1, C18:0, and C18:1. The phospholipid components of the inner membrane were phosphatidylethanolamine, cardiolipin, phosphatidylglycerol, and phosphatidylserine. It is evident that the effects of elevated hydrostatic pressure are comparable to the effects of low temperature on both the fatty acid composition of the inner membrane lipids and the phospholipid composition of the inner membrane of this bacterium.  相似文献   

17.
Male weanling rats were fed diets containing 20% (w/w) fat differing in fatty acid composition for 24 days. Synaptic plasma membranes were isolated from the brain and the fatty acid composition of phosphatidylethanolamine and phosphatidylcholine was determined. In vitro assays of phosphatidylethanolamine methyl-transferase activity were performed on fresh membrane samples to assess effect of dietary fat on the rate of phosphatidylethanolamine methylation for phosphatidylcholine synthesis via the phosphatidylethanolamine methyltransferase pathway. Dietary level of n-6 and ratio of n-6 to n-3 fatty acids influenced membrane phospholipid fatty acid composition and activity of the lipid-dependent phosphatidylethanolamine methyltransferase pathway. Rats fed a diet rich in n-6 fatty acids produced a high ratio of n-6/n-3 fatty acids in synaptosomal membrane phosphatidylethanolamine, and elevated rates of methylation of phosphatidylethanolamine to phosphatidylcholine by phosphatidylethanolamine methyltransferases, suggesting that the pathway exhibits substrate selectivity for individual species of phosphatidylethanolamine containing long-chain homologues of dietary n-6 and n-3 fatty acids (20:4(n-6), 22:4(n-6), 22:5(n-6) and 22:6(n-3). It may be concluded that diet alters the membrane content of n-6, n-3 and monounsaturated fatty acids, and that change in phosphatidylethanolamine species available for methylation to phosphatidylcholine alters the rate of product synthesis in vivo by the phosphatidylethanolamine methyltransferase pathway.  相似文献   

18.
1. The amount and types of phospholipid and the fatty acid composition of the various phospholipids were examined in intact rat liver mitochondria, in mitochondria devoid of their outer membrane (preparation A) and in very small pieces derived from the disruption of the inner-membrane complexes (preparation B). The latter two preparations were obtained by digitonin treatment and carry out oxidative phosphorylation. 2. The ratio mug.atoms of phospholipid P/mg. of protein was 0.163 for intact mitochondria, decreased to 0.118 on removal of the outer membrane and increased markedly to 0.292 on disruption of the inner-membrane complex. 3. Examination of the various types of phospholipid present showed that the molar proportions cardiolipin:phosphatidylcholine:phosphatidylethanolamine were approx. 1:6:6 for intact mitochondria and 1:3:3 for preparations A and B. 4. There was a correlation between the recovery of cardiolipin and adenosine triphosphatase activity in the conversion of intact mitochondria into preparations A and B. 5. The fatty acid contents of the various types of phospholipid purified by thin-layer chromatography were identical in all three preparations. Our results show a considerably higher content of arachidonic acid and lower content of oleic acid for phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol than have previously been reported for mitochondrial phospholipids.  相似文献   

19.
Highly enriched plasma membrane fractions were isolated from leaves of nonacclimated (NA) and acclimated (ACC) rye (Secale cereale L. cv Puma) seedlings. Collectively, free sterols, steryl glucosides, and acylated steryl glucosides constituted >50 mole% of the total lipid in both NA and ACC plasma membrane fractions. Glucocerebrosides containing hydroxy fatty acids constituted the major glycolipid class of the plasma membrane, accounting for 16 mole% of the total lipid. Phospholipids, primarily phosphatidylcholine and phosphatidylethanolamine with lesser amounts of phosphatidylglycerol, phosphatidic acid, phosphatidylserine, and phosphatidylinositol, comprised only 32 mole% of the total lipid in NA samples. Following cold acclimation, free sterols increased from 33 to 44 mole%, while steryl glucosides and acylated steryl glucosides decreased from 15 to 6 mole% and 4 to 1 mole%, respectively. Sterol analyses of these lipid classes demonstrated that free β-sitosterol increased from 21 to 32 mole% (accounting for the increase in free sterols as a class) at the expense of sterol derivatives containing β-sitosterol. Glucocerebrosides decreased from 16 to 7 mole% of the total lipid following cold acclimation. In addition, the relative proportions of associated hydroxy fatty acids, including 22:0 (h), 24:0 (h), 22:1 (h), and 24:1 (h), were altered. The phospholipid content of the plasma membrane fraction increased to 42 mole% of the total lipid following cold acclimation. Although the relative proportions of the individual phospholipids did not change appreciably after cold acclimation, there were substantial differences in the molecular species. Di-unsaturated molecular species (18:2/18:2, 18:2/18:3, 18:3/18:3) of phosphatidylcholine and phosphatidylethanolamine increased following acclimation. These results demonstrate that cold acclimation results in substantial changes in the lipid composition of the plasma membrane.  相似文献   

20.
Changes in fatty acid, phospholipid and galactolipid contents during cellular and organ differentiation in Aegle marmelos have been described. Decrease in phosphatidylinositol content and presence of 3-trans-hexadecenoic acid in phosphatidylglycerol were related to greening and shoot buds differentiation. The galactolipids level, the monogalactosyl diglyceride/digalactosyl diglyceride ratio and the linolenic acid level (mainly in monogalactosyl diglyceride) increased with the degree of differentiation, indicating the possible biogenesis of functional chloroplasts.Abbreviations 2,4-D 2,4 dichlorophenoxyacetic acid - BA benzylaminopurine - DW dry weight - FW fresh weight - PC phosphatidylcholine - PE phosphatidylethanolamine - PI phosphatidylinositol - PG phosphatidylglycerol - PS phosphatidyl serine - MGDG monogalactosyl diglyceride - DGDG digalactosyl diglyceride - 16:0 palmatic acid - 18:0 stearic acid - 18:1 oleic acid - 18:2 linoleic acid - 18:3 linolenic acid - trans-16:1 3-trans-hexadecenoic acid  相似文献   

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