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1.
The fatty acid composition of five strains ofCorallococcus coralloides and three reference species ofMyxococcus were determined by gas-liquid chromatography. Methyl esters of fatty acid containing from 12 to 22 carbon atoms were identified. The major fatty acids present were C15 and C17 saturated branched chain, and both C16 saturated and unsaturated straight chain acids. The C17 saturated branched and straight chain acids, which were in valuable concentration in species ofMyxococcus, were not, however, detected in all strains ofC. coralloides. The application of these results in the distinction ofC. coralloides from the genusMyxococcus is discussed.  相似文献   

2.
Under the action of the sub-bacteriostatic concentration (0.02 microgram/ml) of antibiotic AL-87 there formed in all the fractions of phospholipids and neutral lipids of S. aureus 209P unsaturated branched fatty acids not detected in the control and the content of shorter chain saturated branched fatty acids increased. This means that there were changes leading to increased lipid fluidity. The findings showed that fatty acids of the neutral lipids and phospholipids were involved in regulation of the bacterial cell functional state and participated in this case in providing increased membrane fluidity and permeability.  相似文献   

3.
The stability of fatty acid composition of total extractable lipids was studied in Streptomyces cultures. The type of fatty acid composition typical of the Streptomyces genus remains stable when the actinomycetes were grown as submerged cultures in various synthetic media: saturated fatty acids with methyl branching in the chain predominated in all of the cases, and fatty acids with an uneven number of carbon atoms in the chain prevailed in most of the cases. Fatty acids with the anteiso structure predominated among the acids with a branched chain, amounting to more than a half of the latter and reaching sometimes 50% of the total fatty acid content. Methyl branchings were located in the anteiso position in fatty acids with an uneven number of carbon atoms, and in the iso position in fatty acids with an even number of carbons. Unsaturated fatty acids were found as a minor component.  相似文献   

4.
Fatty acid composition of the phospholipids of mouse LM cells grown in suspension culture in serum-free chemically defined medium was modified by supplementing the medium with various fatty acids bound to bovine serum albumin.Following supplementation with saturated fatty acids of longer than 15 carbons (100 μM) profound inhibition of cell growth occurred; this inhibitory effect was completely abolished when unsaturated fatty acids were added at the same concentration. Supplementing with unsaturated fatty acids such as linoleic acid, linolenic acid or arachidonic acid had no effect on the cell growth.Fatty acid composition of membrane phospholipids could be manipulated by addition of different fatty acids. The normal percentage of unsaturated fatty acids in LM cell membrane phospholipids (63%) was reduced to 35–41% following incorporation of saturated fatty acids longer than 15 carbon atoms and increased to 72–82% after addition of unsaturated fatty acids.A good correlation was found between the unsaturated fatty acid content of membrane phospholipids and cell growth. When incorporated saturated fatty acids reduced the percentage of unsaturated fatty acids in membrane phospholipids to less than 50%, severe inhibition of the cell growth was found. Simultaneous addition of an unsaturated fatty acid completely abolished this effect of saturated fatty acids.  相似文献   

5.
Total and individual phospholipids ofStreptomyces griseus exhibit a predominance of iso and anteiso fatty acids. The ratio of saturated straight chain fatty acids to branched chain plus unsaturated fatty acids remained unchanged during growth.  相似文献   

6.
Injections of albino rats with antioxidants of the ionol group cause cyclic changes in the energy state of liver mitochondria which are correlated with changes in the fatty acid composition of mitochondrial membranes. The increase in the degree of coupling between oxidation and phosphorylation coincides in time with the increment in the content of saturated fatty acids and a decrease in the unsaturated fatty acid content in the total fraction of mitochondrial membrane lipids. Conversely, the activation of the external pathway of NADH oxidation and a decrease of the respiratory control are correlated with the diminution of the saturated fatty acid content and an increased percentage of unsaturated fatty acids. These changes are especially well pronounced in the case of fatty acids carrying 18 carbon atoms.  相似文献   

7.
An analysis of the phospholipid ester-linked and the lipopolysaccharide (LPS) fatty acids and hydroxy fatty acids of six lactate-utilizing Desulfovibrio-type sulfate-reducing bacteria (SRB) has been performed using capillary gas-liquid chromatography-mass spectrometry (GLC-MS). The concentrations of normal fatty acids were essentially similar, with the possible exception of a high content of normal fatty acids in the LPS of Desulfovibrio gigas. Determination of monounsaturated acid double bond configuration was performed by GLC-MS analysis of the derivatized fatty acids. A total of nine branched chain and eight straight chain monounsaturated fatty acids was detected in the Desulfovibrio species analyzed. The major component detected in five Desulfovibrio was the 17-carbon iso-branched monoenoic acid which showed cis unsaturation [i17:1(n-7)c] seven carbons from the terminal methyl group of the fatty acid chain. D. gigas, in contrast, contained almost no unsaturated fatty acids and was greatly enriched in iso-branched 15:0. Major differences between strains were found in the phospholipid and LPS hydroxy fatty acids. These components, in addition to the i17:1(n-7)c and other characteristic branched chain unsaturated acids, can possibly be utilized as signatures of the lactate-utilizing SRB.  相似文献   

8.
Growth and sporulation of a Bacillus subtilis mutant deficient in branched fatty acid synthesis (gene symbol bfmB) were examined. The mutant, which produces an acyl-coenzyme A:acyl carrier protein transacylase with reduced affinity for branched fatty acid primers, could grow in media containing any one of a wide range of low-molecular-weight fatty acids having branched, cyclic, saturated, or unsaturated carbon chains. The fatty acid composition of cellular lipids depended on the compound used to support growth. Cultures of the bfmB mutant grown in the presence of 3-methylcrotonate contained an unusually high fraction (73%) of straight-chain fatty acids in the cellular lipids. The mutant sporulated with any one of the precursors of branched fatty acids in the medium; isolated spores contained mainly this branched fatty acid and only 10% or less straight-chain fatty acids regardless of the straight-chain fatty acid content of vegetative cells. Exceptional were spores grown in the presence of cyclobutane-carboxylic acid, which contained 28% straight-chain fatty acids. The branched fatty acid composition of spores could be modified greatly by changing the supply of precursors in the medium.  相似文献   

9.
Seven strains of Arthrobacter globiformis , and one each of A. crystallopoietes and A. nicotianae , isolated from the water fern Azolla, were cultured for 2–3 d at 30 °C on Pseudomonas Agar F to obtain rods and for 5 d to obtain cocci, then analysed for total cellular fatty acids. In rods, saturated iso - and anteiso -branched 13–19 carbon fatty acids averaged 85% of the total in A. globiformis , 81% in A. crystallopoietes , and 97% in A. nicotianae . Minor components included unsaturated branched chains, hydroxy and cyclopropane fatty acids. Fatty acid composition of A. globiformis was similar to that of A. crystallopoietes but different from that of A. nicotianae . Saturated straight chains in A. nicotianae averaged 1·5% of the total compared with 14–16% in A. globiformis/crystallopoietes , and anteiso -15:0 constituted 73% of the total in A. nicotianae compared with 18–19% in the other species. Composition of cocci was different from that of rods in A. globiformis and A. crystallopoietes. As cells changed from rods to cocci, percentages of saturated and unsaturated straight chains decreased and saturated iso - and anteiso -branched chains increased. In A. nicotianae there were no significant differences in the fatty acids between rods and cocci.  相似文献   

10.
The composition of fatty acids of methicillin-resistant (MR) and methicillin-sensitive (MS) strains of Staph. aureus and Staph. epidermidis was determined with the method of reactive gas liquid chromatography. The MS staphylococci of the above species differed by the content of acids with branched chains of iso- and anteisostructures and straight chains. Anteisoacids in the cells of Staph. epidermidis amounted almost to 80 per cent of the total number of the acids, while in the cells of Staph. aureus, their total number amounted only to a half of the fatty acid pool. Comparison of the composition of the fatty acids of the MS and MR strains of Staph. aureus revealed differences in the proportions of the anteiso- and isoacids. The total number of the long-chain C20.0 acid in the cells of Staph. epidermidis resistant to methicillin was lower as compared to that in the sensitive cells.  相似文献   

11.
The possibility was considered that the sleep-like state seen after injection of short chain fatty acids salts into animals is a result of inhibition of the sodium-potassium activated ATPase. Tris salts of short chain fatty acids inhibited brain Na-K ATPase activity in vitro at concentrations similar to intravenous levels causing narcosis in vivo. The inhibition depended on the logarithm of the concentration of a given acid. The concentration of acid anion which caused 50 per cent inhibition of the enzyme system (I50) was determined for straight and branched chain acids with 4-12 carbon atoms per molecule. The log of I50 concentrations plotted against the number of carbon atoms in the molecule gave a straight line; the inhibitory capacity of an acid increased by a factor of 2.3 for each--CH2--added to the carbon chain. It is suggested that both fatty acid narcosis and the enzyme inhibition result from fatty acid molecules forming an ordered array along the membrane in association with membrane lipids.  相似文献   

12.
It is found out that the content of lipids in the biomass of the studied populations of Eisenia foetida is rather high: 2.5-5.2% of the wet mass. The content of phospholipids is 40-55%, C27-sterols--1.5-3.4% of the mass of coarse extracts of lipids. Lipids of tissues contain also 47-54% of saturated (C10-C24) fatty acids as well as to 23% of monoene and to 13% of polyene unsaturated (C14-C22) fatty acids. The acids with the odd number of carbon atoms compose about 25% and acids with a branched carbon chain about 23% of the above percentage. Considerable content of lipids and biologically active fatty acids in tissues of the studied object permits considering it as a promising source of raw materials for production of valuable pharmacological preparations.  相似文献   

13.
The gasochromatic method was applied to the study of the cellular fatty acids composition in diphtheria and nonpathogenic corynebacteria (diphtheroids and psendo diptheria bacillus). Marked differences in the content of unsaturated fatty acids were revealed in them. Thus, palmito leic acid served the preponderant unsaturated fatty acid in Corynebacteria diphtheriae, and unsaturated fatty acids with 18 carbon atoms (octadeconoic and linoleic)--in nonpathogenic corynebacteria. The mentioned changes permit use this sign as differential. When grown on Loeffler's medium all the corynebacteria under study had a similar fatty acid composition characterized by the prevalence of unsaturated fatty acids with 18 carbon atoms. On the basis of studying the fatty acid spectrum of the nutrient media used it is supposed that one of the factors determining the revealed dependence of the corynebacterial fatty acid composition on the culture medium was the fatty acid composition of the latter.  相似文献   

14.
A M Melin  M A Carbonneau  N Rebeyrotte 《Biochimie》1986,68(10-11):1201-1209
Fatty acid composition and lipidic carbohydrate to lipidic phosphorus molar ratio of yellow pigmented micrococci are compared to red pigmented ones and may be summarized by three indexes. These bacteria show wide differences in their fatty acid composition: three strains possess saturated branched chain fatty acids and one has unsaturated straight chain ones. A significant increase in 'anteiso/iso indexes' is observed between pink (M. roseus) and yellow colored bacteria (M. lysodeikticus, S. lutea). There is no significant difference (P greater than 0.05) between the 'unsaturation indexes' of the red pigmented parental D. radiodurans strain and its colorless mutant. Radioresistant strains exhibit a higher 'carbohydrate/phosphorus index' than other strains. There seems to be a relationship between a high carbohydrate-containing lipid content and a high resistance to physical and chemical agents, in particular to radiations. These differences observed in the lipid composition have implications in taxonomy and in establishing an evolutionary scheme.  相似文献   

15.
The fatty acid composition of cardiolipin from the Harderian gland of guinea pig was examined by gas chromatography and gas chromatography-mass spectrometry. At least 33 kinds of fatty acids were detected. Oleic acid was the most prominent component, accounting for 18.2 mol% of the total fatty acids. About 70.2 mol% of fatty acids had methyl branches. Ethyl branches were also detected (1.3 mol%). Straight chain saturated acids comprised only 10.3 mol%. On the other hand, linoleic, linolenic, and arachidonic acids were not found in this lipid. The 2-(2'-) acyl moieties contained larger amounts of oleic acid and smaller amounts of branched chain acids than the 1-(1'-)acyl moieties, but the saturated straight chain acids showed even distribution between the 1-(1'-) and 2-(2'-)positions. The fatty acids of cardiolipin from the liver of the same animal were also examined. Linoleic acid was the most abundant component (66.9 mol%), and saturated straight chain acids occupied 21.9 mol%. Branched chain acids were detected but comprised only 11.2 mol%.  相似文献   

16.
This study examines certain membrane-related aspects of oxygen poisoning in Escherichia coli K1060 (fabB fadE lacI) and its parent strain, K-12 Ymel. Cells were grown to exponential or stationary phase in a minimal medium and exposed to air plus 300 lb/in2 of O2 as a suspension in minimal salts. After an initial lag, both strains lost viability with apparent first-order kinetics. Hypebaric oxygen was more toxic to cells harvested during the exponential phase of growth than to cells harvested from the stationary phase of growth for both strains K-12 Ymel and K1060. Control suspensions exposed to air plus 300 lb/in2 of N2 did not lose viability during a 96-h exposure. The sensitivity of the unsaturated fatty acid auxotroph, strain K1060, to hyperbaric oxygen increased as the degree of unsaturation of the fatty acid supplement increased. Cells grown with a cyclopropane fatty acid (9,10=methylenoctadecanoate) were the most resistant; cells grown with a monounsaturated fatty acid (oleate) were intermediate; and those grown with polyunsaturated fatty acids (linoleate and linolenate) were most sensitive to hyperbaric oxygen. The parent strain, K-12 Ymel, lost viability in hyperbaric oxygen most similarly to strain K1060 supplemented with oleate. To determine the relative effect of hyperbaric oxygen on the survival of E. coli with saturated membranes, substrains of K1060 were selected for growth on 12-methyltetrade-canoate or on 9 or 10-monobromostearate. Substrains grown with a saturated fatty acid supplement were equally or more sensitive to hyperbaric oxygen than when the same substrains were grown with a cyclopropane fatty acid supplement. The lipid acyl chain composition was determined in E. coli K1060 before and after exposure to hyperbaric oxygen or hyperbaric nitrogen. The proportion of nonsaturated acyl chain lipid of either the oleate- or the 9,10-methyleneoctade-canoate-supplemented K1060 remained unchanged after hyperbaric gas exposure. In strain K1060 supplemented with linoleate and grown to stationary phase, however, the relative unsaturated acyl chain content after hyperbaric exposure decreased in both gases. This finding prompted an investigation of the role of lipid oxidation in hyperbaric oxygen toxicity. Assays of potential lipid oxidation products were performed with linoleate-grown cells. The lipid hydroperoxide and peroxide content of the lipid extract increased by 6.9 times after 48 h of air plus 300 lb/in2 of O2; malondialdehyde and fluorescent complex lipid oxidation products showed much smaller or no changes. Lipid extracts from hyperbaric oxygen-exposed cells were not toxic to viable E. coli K1060, nor did they increase the rate of loss of viability in cells simultaneously exposed to hyperbaric oxygen. Linoleic acid hydroperoxide at 1.0 mM had no effect on the viability of E. coli K-12 Ymel and only marginally decreased the viability of E. coli K1060 supplemented with linoleate. We conclude that the kinetics of oxygen toxicity in E...  相似文献   

17.
The in vivo effects of ethanol on lipid synthesis in Escherichia coli have been examined. Under conditions which uncoupled fatty acid synthesis from phospholipid synthesis, ethanol decreased the amount of saturated fatty acids synthesized but had little effect on the selectivity of their incorporation into phospholipids. In the absence of fatty acid degradation and unsaturated fatty acid synthesis, E. coli was still able to adapt its membrane lipids to ethanol, while the inhibition of total fatty acid synthesis eliminated this response. During growth in the presence of ethanol, strain K1060 (an unsaturated fatty acid auxotroph) incorporated an increased amount of exogenous heptadecanoic acid (17:0) to compensate for the reduction in palmitic acid (16:0) available from biosynthesis. Thus, our results indicate that the reduced levels of saturated fatty acids observed in the phospholipids of E. coli following growth in the presence of ethanol result primarily from a decrease in the amounts of saturated fatty acids available for phospholipid synthesis.  相似文献   

18.
Actinomycetes belonging to the genus Nocardia were isolated from the surface horizon of 15 out of 46 soil samples examined. All the nocardiae strains isolated contained mycolic acids and saturated and unsaturated straight chain fatty acids (from 12 to 18 carbon atoms) and tuberculostearic acid and were biochemically identified as members of the Nocardia asteroides complex. Nocardiae were detected in alluvial, brown, and serosem great soil groups, but not in calcic brown, solontchack, and regosol great soil groups. Numbers of nocardiae isolated varied from 5.12 X 10(2) to 1.21 X 10(4) colony-forming units per gram of dry weight, and they were statistically correlated with the carbon content (percent C) of the soil. Soil samples were, in general, very dry.  相似文献   

19.
Whole cell acid methanolysates from corynebacteria of the D2 group were found to contain meso-diaminopimelic acid, arabinose and galactose. Among lipids of taxonomic value, saturated and unsaturated straight chain fatty acids (14 to 18 carbon atoms), tuberculostearic acid (10-methyl octadecanoic acid) and mycolic acids were present. The last compounds ranged from 26 to 36 carbon atoms, the predominant types being 28.2, 28.1, 30.3, 30.2, 32.3 and 32.2. By reverse phase thin-layer chromatography the major menaquinone was identified as MK-9(H2)-containing nine isoprene units with two additional hydrogens. Moreover, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol and phosphatidylinositol mannosides were detected among the phospholipids of these bacteria. Thus, on these bases, the D2 group appears to be closely related to the true corynebacteria.  相似文献   

20.
The fatty acid composition of lipids was compared among yeast cultures belonging to the genera Rhodotorula, Lipomyces, and Cryptococcus. These lipids contain C10--C26 fatty acids, mainly with the even number of carbon atoms. Palmitic acid (C16 : 0) and oleic acid (C18 : 0) predominate. In the majority of the strains, the sum of unsaturated acids exceeds the sum of saturated acids. The content of unsaturated acids in the lipids of the epiphytic yeast Rhodotorula is higher than in the soil yeast Lipomyces. Besides C12--C18 acids, C22--C26 acids were identified by GLC at preset temperatures. Lignoceric acid (C24 : 0) was found for the first time in the cultures of Rhodotorula, Lipomyces, and Cryptococcus, and cerotinic acid (C16 : 0) was also detected in the Rhodotorula yeast. Fatty acids with a long chain are registered in the strains of Rhodotorula more often than in the strains of Lipomyces and Cryptococcus.  相似文献   

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