Total Cellular Fatty Acids Research Articles

Decreased Erythrocyte and Platelet Phospholipids and Fatty Acids in Juvenile Neuronal Ceroid-Lipofuscinosis (Batten Disease)

Total cellular and phospholipid fatty acids were analyzed in erythrocytes and platelets from six patients with juvenile neuronal ceroid-lipofuscinosis (Spielmeyer-Vogt, Batten disease, JNCL). The results were compared to those of age-matched controls. The amounts of total fatty acid and the phospholipid classes, phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylserine (PS) were significantly decreased in patients when related to cellular protein. The reductions in total fatty acids were 27% in erythrocytes and 50% in platelets. Erythrocyte PC reduction was 36%, PE was 44% and PS 27%. There were no major qualitative differences in the phospholipid fatty acids, suggesting that the fatty acid composition of the reduced phospholipid was normal, and that there is a generalized phospholipid deficiency in these cells in JNCL. This was not related to nutritional status. The pathogenesis of Batten disease may be related to abnormal membrane function resulting from this marked phospholipid deficiency.

Fatty acid composition and primer specificity of de novo fatty acid synthetase in Bacillus globispores, Bacillus insolitus, and Bacillus psychrophilus.

The fatty acid compositions of three psychrophilic species of Bacillus were determined by gas--liquid chromatography. The proportions of straight-chain fatty acids, branched-chain fatty acids, and unsaturated fatty acids were found to be 13.3, 86.7, and 26.1% of the total cellular fatty acids for Bacillus globispores, 36.6, 63.4, and 25.1% for Bacillus insolitus, and 6.9, 93.1, and 18.4% for Bacillus psychrophilus, respectively. In all three organisms the de novo fatty acid synthetase specificity towards acyl-CoA primers was butyryl-CoA greater than propionyl-CoA much greater than acetyl-CoA. This shows that B. insolitus, which has an unusually large proportion of straight-chain fatty acids for Bacillus, does not possess a different de novo fatty acid synthetase than the other two organisms. Therefore, the greater proportion of straight-chain fatty acids in B. insolitus may be explained by a large supply of straight-chain primer.

Stereoselective synthesis of chaulmoogric acid and related fatty acid from 2-(±)-cyclopentenecarboxylic acid by Bacillus subtilis (ATCC 7059)

2-(±)-Cyclopentenecarboxylic acid added to the culture medium is incorporated into two new fatty acids by the growing cells of Bacillus subtilis (ATCC 7059). The new fatty acids, amounting to 24% of the total cellular fatty acids, are identified as hydrocarpic [11-(2′-cyclopentenyl)-hendecanoic] and chaulmoogric [13-(2′-cyclopentenyl)-tridecanoic] by gas-liquid chromatography and mass spectrometry. These C 16 and C 18 fatty acids are optically active, levorotatory, with the specific rotation of −50.4° as mixture, thus the optical purity of approximately 80%. This indicates that the optical rotation of these bacterial fatty acids are opposite with that of the fatty acids from plant oils.

Cellular distribution and linkage of D-(-)-3-hydroxy fatty acids in Bacteroides species.

Two strains of Bacteroides asaccharolyticus and two strains of Bacteroides fragilis were analyzed for total fatty acid, total lipid fatty acid, and total bound fatty acid profiles. Extracted lipids and defatted cell residues were subjected to sequential alkaline and acid methanolyses to distinguish ester- and amide-linked fatty acids in each fraction. In the lipid fractions, all the ester-linked fatty acids were nonhydroxylated, whereas all of the amide-linked fatty acids were hydroxylated. In the nonextractable fractions, both hydroxy and nonhydroxy fatty acids were found in both ester and amide linkage, although hydroxy acids predominated. The fatty acid profiles of the bound fractions differed widely from those of the lipid fractions. Bound fatty acid represented approximately 10% of the total cellular fatty acids.

ATYPICAL LEGIONELLA-LIKE ORGANISMS: FASTIDIOUS WATER-ASSOCIATED BACTERIA PATHOGENIC FOR MAN

A group of related bacteria designated atypical Legionella-like organisms (ALLO) has been identified. ALLO, like L. pneumophila, are fastidious gram-negative rods that grow well on charcoal yeast extract (CYE) agar and produce ground glass colonies and browning of modified yeast extract agar. Unlike L. pneumophila, ALLO do not grow well on Feeley-Gorman (FG) agar, and on CYE agar they fluoresce under longwave ultraviolet light. ALLO and L. pneumophila have a similar predominance of branched-chain forms among total cellular fatty acids but have distinctive fatty-acid profiles. 2 patients with culture-verified ALLO pneumonia and 10 with pneumonia of uncertain ætiology who seroconverted to ALLO offer evidence that ALLO may be a cause of community-acquired pneumonia. Like L. pneumophila,ALLO appear to be water-associated; both persons with culture-verified ALLO infection were exposed to fresh water or its contents before becoming ill, and two strains of ALLO were isolated from water or wet environments.

Differences in cellular fatty acids and lipid composition inClostridium pasteurianum under nitrogen-and non-nitrogen-fixing conditions

Clostridium pasteurianum total cellular saturated fatty acids increased through its growth cycle from 81% to 91% but varied significantly in the composition under nitrogen- and non-nitrogen-fixing conditions. During ammonia-assimilating growth, palmitic acid decreased from 67.7% to 43.5% by late log while marked increases in shorter chain saturated fatty acids (C15:0 and below) and a long chain saturated C22:0 occured. In contrast, under N2-fixing growth conditions, palmitic acid increased from 45.5% to 84.3% by late log, representing nearly the total amound of saturated fatty acids found inC. pasteurianum. The total cellular lipid concentration decreased as the culture aged. irrespective of the nitrogen sources; however, the phospholipid concentration increased significantly during N2-fixing growth as compared with a 50% decrease during ammonia-assimilating conditions. The implication of these differences and possible role of palmitic acid and phospholipids inC. pasteurianum nitrogen fixation process are discussed.

Delta 15,18-tetracosadienoic acid content of sphingolipids from platelets and erythrocytes of animals fed diets high in saturated or polyunsaturated fats.

AbstractThe effect of diets high (15%) in saturated (beef tallow) or polyunsaturated (corn or cottonseed oil) fatty acids on the fatty acid composition of sphingomyelin from canine erythrocytes and platelets and sphingomyelin and neutral glycosphingolipids of swine erythrocytes was determined. Sphingolipids of platelets and erythrocytes from animals fed high levels of corn or cottonseed oil exhibited a dramatic alteration in their fatty acid composition, most notable of which was a 50% reduction in nervonic acid (24∶1ω9) as compared to levels observed in control or tallow fed animals. This decrease was compensated for by a quantitatively similar increase in a C24 dienoic acid. The long chain dienoic acid was isolated by silver nitrate thin layer chromatography and determined by analysis of its oxidation products to be Δ15, 18‐tetracosadienoic acid (24∶2ω6). When the animals were fed the diets high in polyunsaturates, the 24∶2ω6 represented 13, 20, and 9% of the sphingomyelin fatty acids from canine erythrocytes, platelets, and swine erythrocytes, respectively, and 5% of the neutral glycosphingolipid fatty acids of swine erythrocytes. In contrast, the 24∶2ω6 represented less than 4% of the total cellular sphingolipid fatty acids in animals fed the control or high beef tallow diets. The 24∶1ω9 in the sphingolipids of the animals fed the polyunsaturated diet was roughly equal to that of 24∶2ω6, whereas in the sphingolipids of animals fed the control or saturated fat (beef tallow) diet, the 24∶1ω9 was twice these values. Since sphingomyelin is a membrane component, the increase in unsaturation (24∶2ω6) in its fatty acid moiety induced by dietary polyunsaturates may affect membrane fluidity and may alter membrane properties.

FATTY ACID DYNAMICS IN THALASSIOSIRA PSEUDONANA (BACILLARIOPHYCEAE): IMPLICATIONS FOR P HYSIOLOGICAL ECOLOGY1,2,3

ABSTRACT The growth dry weight, fatty acid weight and fatty acid composition of two clones of Thalassiosira pseudonana Hasle & Heimdal were measured under several growth conditions. Determinations of total cellular fatty acids were made using chemical ionization mass spectrometry. Both clones had the same fatty acids, dominated by C14:0, C16:0, C16:1, C16:3, C16:4, C18:4 and C20:5, though in different relative amounts. Fatty acids typically represented 5–10% the dry weight of a cell during log Phase growth and up to 22% during stationary Phase. The C16 fatty acids of both clones changed as the cultures aged, though much more markedly in the Sargasso Sea done (13–1) than in the estuarine one (3H). The C16:0 and C16:1 acids of both clones declined sharply in the dark and were replenished in the light. Cells maintained in constant illumination, but with no cell division. produced large quantities of these acids. Cells of done 13–1 treated with polychlorinated biphenyl (PCB) initially grew more slowly than control cells, weighed more, and had higher relative amounts of C16:0 and C16:1. Fatty acid studies may provide useful indicators of ecologically important energy reserves and membrane adaptations in the algae.

Comparative Study of the Total Cellular Fatty Acids of Staphylococcus Species of Human Origin

The cellular fatty acid compositions of 100 strains representing 10 different species of Staphylococcus were analyzed by gas-liquid chromatography. Results indicated that the fatty acid compositions of the various species were qualitatively similar with the exception of that of S. warneri, which contained a C22 fatty acid component. The species differed quantitatively with respect to relative percentages of fatty acid components. The major fatty acids were C15Br, C17Br, C16, C18, and C20. S. warneri and S. saprophyticus can be differentiated in most cases from all of the other species studied by the presence of significantly higher percentages of C20 and C16 fatty acids, respectively. Other species or groups of related species could also be separated on the basis of combinations of fatty acid components. These findings corroborate the newly proposed scheme of classification of the staphylococci, but the particular usefulness of gas-liquid chromatography of fatty acids for the identification of clinically significant, coagulase-negative staphylococci from humans is primarily limited to S. saprophyticus and possibly S. haemolyticus. However, application of the method may be useful in clarifying further the phenetic relationships of certain species and may have some ecological value.

Rapid determination of the molecular weight distribution of total cellular fatty acids using chemical ionization mass spectrometry

A new method for the qualitative and quantitative determination of the molecular weight distribution of total cellular fatty acids is described. The method includes a simple extraction-saponification followed by chemical ionization-mass spectrometric analysis of the saponifiable matter. This technique requires small quantities of cell material which, combined with the rapidity and precision of the analysis, makes it attractive to the biologist interested in changes in the fatty acid composition of growing cells. As an example, an application of this method to the fatty acid determination of marine diatoms at different growth stages is presented.

Candida lipolytica mutants defective in an acyl-CoA synthetase

Mutant strains of Candida lipolytica NRRL Y-6795, which are defective in ‘fatty acyl-CoA synthetase I’ linking to the system incorporating the fatty acyl moiety into cellular lipids (Kamiryo, et al., 1977), were cultivated on various carbon sources including odd-chain n-alkanes (C11 to C17) and their fatty acid compositions were examined. In the case of the wild-type strain grown on odd-chain n-alkanes (from C13 to C17), the proportions of odd-chain cellular fatty acids to total cellular fatty acids were markedly high, reaching 98–99% in the n-pentadecane- and n-heptadecane-grown cells. Those of the mutant strains, however, were drastically low, being at most 12–13% even in the n-heptadecane-grown cells. The total fatty acid contents in the mutant cells were 4–5% in dry weight, being slightly lower than those of the wild strain (4–7% in dry weight). The growth rates of the mutants on glucose, n-undecane and n-tridecane were comparable to those of the wild strain. When n-pentadecane, n-heptadecane, or oleic acid was used as carbon source, the mutants had lower, but still practicable, growth rates. The results obtained indicate that these mutant strains of Candida lipolytica will be useful as sources of biomass with low content of nonnatural odd-chain fatty acids.

Membrane lipid biosynthesis in Acholeplasma laidlawii B: de novo biosynthesis of saturated fatty acids by growing cells.

The de novo biosynthesis of fatty acids of 12 to 18 carbons from precursors of 5 carbons or fewer has been demonstrated in Acholeplasma laidlawii B. Radiolabeling experiments indicated that the normal primers for the synthesis of the even- and odd-chain fatty acids are acetate and propionate or valerate, respectively. Saturated straight-chain monomethyl-branched fatty acids of up to five carbons were readily utilized as primers, wheras more highly branched species and those possessing halogen substituents or unsaturation were not utilized. At primer concentrations of 1 to 3 mM, up to 80% of the total cellular lipid fatty acids were derived from exogenous primer. The mean chain length of the exogenous primer-derived fatty acids rose with increasing primer incorporation for methyl-branched short-chain fatty acids but was invariant for propionate. The products of de novo biosynthesis varied only slightly with temperature or cholesterol supplementation, suggesting that de novo biosynthesis is not directly influenced by membrane fluidity. Cerulenin inhibited de novo biosynthesis in a fashion that suggests the presence of two beta-ketoacyl thioester synthetases, which differ in substrate chain length specificity and in susceptibility to inhibition by the antibiotic.

Isolation, characterization, and function of 6-mycolyl-6'-acetyltrehalose in the H37Ra strain of Myocobacterium tuberculosis.

The major mycolic acid containing extractable lipid of the H37Ra strain of Mycobacterium tuberculosis was established to be 6-mycolyl-6'-acetyltrehalose (MAT). This new glycolipid was extracted from harvested cells with chloroform-methanol (2:1, v/v) and initially precipitated out in acetone. A series of column (DEAE-cellulose, silicic acid, and Sephadex LH-20) and preparative thin-layer chromatography steps yielded a homogeneous preparation. A single sugar was released by saponification and it was identified to be trehalose by paper chromatography and gas-liquid chromatography of the trimethylsilyl derivative. The lipid moiety was determined to be exclusively mycolic acids. The major mycolic acid component of this glycolipid was isolated, purified as the methyl ester, and characterized to be methyl alpha-mycolate by nuclear magnetic resonance spectroscopy and mass spectrometry. The molar ratio of trehalose to mycolic acids was determined to be 1:1. The other acyl group in MAT was established to be acetate by gas-liquid chromatography. Methylation analysis showed the mycolate and acetate ester linkages to the 6 and 6' positions of trehalose. The time course of incorporation of 14C-labeled acetate into the mycolates of both MAT and total cellular fatty acids was followed. These results showed that the synthesis of MAT is rapid and linear for the initial 20 min of incubation whereas the curve for the total cellular mycolates minus MAT (an estimate of the cell wall mycolates) had a 25-30-min lag period. When the label in the lipids was chased out with an excess of unlabeled acetate, relatively rapid decline in the labeled MAT resulted with a corresponding rise in the level of radioactivity in the mycolates of the nonextractable cellular fraction (assumed to be the cell wall fraction). Thus mycolic acids are rapidly transferred from MAT to the cell wall of M. tuberculosis.

Lipoidal components of bacterial lipopolysaccharides: nature and distribution of fatty acids in Aerobacter aerogenes.

The fatty acid distribution of Aerobacter aerogenes was studied by comparing the fatty acid composition of the lipoidal component of the endotoxin (lipid A) with the fatty acids of the readily extractable native lipids and total cellular fatty acids. The results for total cellular fatty acids and readily extractable native lipids were generally similar, but both quantitative and qualitative differences exist. In addition, profound differences between these two fractions and lipid A were observed. These differences included fewer fatty acids and lower concentrations of unsaturated and cyclopropane fatty acids in the lipid A. Hydroxy fatty acids persisted in the lipid A. The significance of these differences with respect to mammalian toxicity of endotoxins is discussed.

Fatty acid concentrations in synchronous cultures ofChlorella pyrenoidosa, grown in the presence and absence of glucose

Total cellular fatty acids, of a high-temperature strain ofChlorella pyrenoidosa, were measured during a synchronous growth cycle in continuous light in the presence and absence of glucose.The fatty acid composition, consisting of saturated monoenoic, dienoic, and trienoic C(16) and C(18) fatty acids, remained essentially the same whether or not the cells were grown on glucose.Nearly all of the fatty acids increased irregularly in concentration during the growth cycle, showing a periodism during the prenuclear and cell-division stages of growth. Cultures exposed to glucose showed a more pronounced drop in the concentration of most of the fatty acids during both stages.None of the fatty acid concentrations, some of which have been implicated in the Hill reaction of a number of photosynthetic organisms, reflected the periodism in photosynthetic activity which was previously observed during the synchronous growth cycle of this organism.The changes in fatty acid concentration are discussed with relation to concurrent metabolic and cytological changes during cell maturation in this organism.