Anteiso Fatty Acids Research Articles

Grouping of Xanthomonas campestris pathovars of cereals and grasses by fatty acid profiling1

Fatty acid profiles were prepared for a range of strains representing all 14 Xanthomonas campestris pathovars from the Gramineae. Profiles were complex, containing up to 40 acids, most of which were iso‐ and anteiso‐branched acids. Grouping of profile types generally correlated with pathovar, although pvs translucens, hordei, cerealis, secalis and undulosa could not be differentiated. Pvs graminis, arrhenatheri, poae and phlei formed another profile type although there were some differences between the pathovars. These graminis and translucens groups had similar profiles but could usually be differentiated by the ratios of 15:0 iso/16:0 iso and 15:0 iso/15:0 anteiso fatty acid methyl esters. The other pathovars each had a very different profile type. Pvs oryzae and oryzicola had profiles which were very different from all others. Pv. vasculorum comprised at least two distinct profile types. This did not correlate with host species or geographic distribution. Fatty acid profiling can be used to identify strains of X. campestris pathovars from Gramineae.

The application of isotopic and biogeochemical markers to the study of the biochemistry of organic matter in a macrotidal estuary, the Loire, France

The biogeochemistry of organic matter in a macrotidal estuary, the Loire, France, has been studied for two years during different seasons. Both particulate matter and sediment have been sampled in the riverine zone, in the maximum turbidity zone and in the ocean near the river mouth. Two techniques have been used: carbon isotopic ratio determination and analysis of lipid-marker signatures in the n-alkane, n-alkene and fatty acid series. For the period corresponding to the output of the maximum turbidity zone in the ocean, the complete change of organic matter, continental in nature in the inner estuary, pure marine in the outer estuary is well illustrated by the decrease of δ 13C values and of carbon preference index of n-alkanes. Input sources of organic matter by continental plants, plankton and micro-organisms are discussed from biogeochemical-marker analyses data along with the processes of accumulation of particles and their evolution with the season. Some criteria for evidencing the nature of various organic-matter pools are assessed and compared in different chemical-marker series as follows: high molecular weight n-alkanes and fatty acids, perylene for continental imprints, polyunsaturated 18-, 20- and 22-carbon fatty acids, n-C 17, n-alkenes and squalene for algae imprints, branched iso and anteiso fatty acids, Δ11-C 18:1 for microbial imprints.

Stereoselectivity in the 2-methylbutyrate incorporation into anteiso fatty acids in Bacillus subtilis mutants

Two Bacillus subtilis mutants defective in branched-chain α-ketoacid dehydrogenase can grow when 2-methylbutyrate is provided in trypticase soy medium. Both enantiomers of the acid supported growth of the mutants but the ( S)-(+)-isomer (natural) was more active than the ( R)-(−)-isomer (unnatural). The mutants utilized these isomers as primer to specifically synthesize either enantiomer of anteiso fatty acids. No racemization of the isomer primers was observed during the synthesis. Thus, cells grown with (−)-isomer possessed anteiso fatty acids (over 80%) of the total fatty acids, being entirely the unnatural enantiomer. The stereospecific synthesis was found to be controlled at the step of 2-methylbutyryl-CoA synthesis. In a wild strain, only (+)-specific acyl-CoA synthetase was detected. In the mutants, either enantiomer of 2-methylbutyrate could simultaneously induce both types, (+)-specific and (−)-specific, of acyl-CoA synthetase. (+)-Specific synthetase had a higher activity and affinity towards substrate than (−)-specific synthetase. The detailed preparative procedures for ( R)-(−)- and 2-[3,4- 3 H]methylbutyric acid are described.

Difference in packing properties between iso and anteiso methyl-branched fatty acids as revealed by incorporation into the membrane lipids of Acholeplasma laidlawii strain A

Acholeplasma laidlawii strain A was grown on the long-chain, branched, saturated fatty acids 12-methyltetradecanoic acid (anteiso-C 15), 14-methylhexadecanoic acid (anteiso-C 17), 13-methyltetradecanoic acid (iso-C 15) and 15-methylhexadecanoic acid (iso-C 17), and on the branched-chain fatty acid precursors 2-methylbutanoic acid (anteiso-C 5) and 3-methylbutanoic acid (iso-C 5). The membrane lipid composition as a function of the fatty acid supplement and the growth temperature was determined: (1) The ratio between the two dominating lipids, monoglucosyldiacylglycerol and diglucosyldiacylglycerol, is decreased when anteiso acyl chains replace iso acyl chains in the lipids, and when the acyl chains are elongated from 15 to 17 carbon atoms; (2) the ratio iso / anteiso acyl chains is reduced when the growth temperature is decreased; (3) the average length of the de novo synthesized branched fatty acids is decreased when the growth temperature is lowered, and when anteiso-C 5 is exchanged for iso-C 5 in the growth medium. The lipid regulation mechanisms are interpreted in terms of lipid molecular geometry and self-assembly of lipid molecules. It is concluded that iso and anteiso fatty acids have distinctively different packing properties in a biological membrane, and they mimic straight-chain saturated and cis-monounsaturated fatty acids, respectively, as seen by the way they affect the physicochemical properties of membrane lipids and by the way they are used in lipid regulation mechanisms.

The biosynthesis of n‐[2H7] fatty acids byArthrobacter globiformis from [U‐2H15] octanoic acid

The principal fatty acids present whenArthrobacter globiformis is grown on a glycine medium free of normal fatty acids were found to be the C15 and C16 anteiso fatty acids; only a small amount of the normal fatty acids (C14 and C16) were present. Cells grown on the same medium but supplemented mented with 0.1 mg/ml [U-(2)H(15)]octanoic acid were found to contain an increased amount of the normal fatty acids and these fatty acids were found to be labeled with 7 deuteriums. I concluded that the octanoic acid is degraded by β-oxidation in these cells to [U-(2)H(7)] butyryl-CoA, which then competes with 2-methylbutyryl-CoA for the initiation of fatty acid biosynthesis.

Lipid composition and protoplast-forming capacity of Streptomyces antibioticus.

The lipid and fatty acid composition of a strain of Streptomyces antibioticus has been studied as a function of culture age and glycine concentration in the growth medium. Under all conditions, the main polar lipids were phosphatidylethanolamine, cardiolipin and phosphomannoinositides in order of decreasing abundance; no ornithinolipids were detected. Acylglucoses and menaquinones were found among the nonpolar lipids. The main fatty acids present were anteiso 15:0 and anteiso 17:0. The lipid composition of the cells varied with the age of the culture, but no uniform pattern of variation was found in the cultures grown on different amounts of glycine. Among the cells harvested at the end of the exponential phase of growth, those grown on 2% glycine give the highest yield of protoplast formation. These cells were found to contain low amounts of nonpolar lipids and of phosphatidylethanolamine, and high proportions of anteiso fatty acids. We propose that the membrane bilayer of these cells, because of its peculiar lipid composition, is particularly stable and fluid. As a consequence, the yield and stability of derived protoplasts should be increased.

Sources of cyclopropanoid fatty acids in the mummichog Fundulus heteroclitus

The saturated fatty acids in lipids of the mummichog Fundulus heteroclitus (L.) contain the characteristic bacterial cis-9,10-methylenehexadecanoic and cis-9,10-methyleneoctadecanoic acids in addition to straight-chain, iso, anteiso and multi-branched fatty acids. To ascertain whether the cyclopropanoid fatty acids (CFA) might be used as a marker for bacterial components in the mummichog diet, the saturated fatty acids of detritus were compared with those of fish intestines and their contents, and with those of eviscerated fish. The relative amounts of individual fatty acids in each sample indicated that microorganisms or invertebrate animals that consume microorganisms constitute a part of the mummichog's diet. A similar analysis of anterior and posterior sections of the fish intestines showed a higher concentration of CFA in the posterior section, suggesting that at least some of the cyclic acids might originate from the resident bacterial gut population. When a group of mummichogs was maintained on a beef-liver diet devoid of cyclic acids, carcass lipids were not depleted of CFA. Instead, an increase in concentration was observed. It was concluded that the intestinal microflora have a role in supplying CFA to mummichog lipids. Since the overall results indicate that these acids are derived from commensal bacteria as well as from bacteria associated with the diet, it is not possible to use such compounds as food-chain markers.

The Cellular Fatty Acids of the Sulphate-reducing Bacteria, Desulfobacter sp., Desulfobulbus sp. and Desulfovibrio desulfuricans

Summary: The fatty acid profiles of Desulfobacter sp. grown on acetate and Desulfobulbus sp. grown on propionate, lactate and H2/CO2 were analysed. Desulfobacter sp. grown on acetate and Desulfobulbus sp. grown on H2/CO2 gave mainly even numbered straight chain acids but odd numbered acids predominated in Desulfobulbus sp. grown on propionate, reflecting the use of the growth substrates provided as chain initiators for fatty acid biosynthesis. The cellular fatty acids of Desulfobulbus sp. grown on lactate were distributed approximately evenly between even and odd straight chain acids. In contrast those of Desulfovibrio desulfuricans, were dominated by branched chain iso and anteiso fatty acids, when grown on either lactate or H2/CO2. On the basis of the fatty acid biosynthetic pathways these sulphate-reducing bacteria could be separated into two groups, one comprising Desulfobacter sp. and Desulfobulbus sp. and the other more primitive Desulfovibrio desulfuricans.

Propionate for Fatty Acid Synthesis by the Mammary Gland of the Lactating Goat

Isolated mammary glands of lactating goats were perfused with heparinized and oxygenated blood for 8 to 15h. Adequate quantities of glucose, acetate, and amino acids were added to the perfusate. After addition of propionate to the perfusion blood, concentrations of odd-numbered and of monomethyl-substituted fatty acids other than those with iso and anteiso configuration increased in the milk fat. These acids seem to be synthesized de novo in the mammary gland. The increase of C17.0 concentration was weak and problematic. We suggest that propionate is acting as a precursor for monomethyl-substituted fatty acids by way of methylmalonyl-CoA. The activating effect of propionate administration upon milk fatty acid production was largest for odd-numbered followed by monomethyl-substituted fatty acids. No increase of iso acids was observed in milk fat in the propionate-infused glands whereas the increase of anteiso acids was extremely small. This agrees with the conception that iso and anteiso fatty acids are synthesized by rumen bacteria.

Étude comparative de la composition en lipides de sept espèces de Micromonospora

Analysis of the lipids of seven species of Micromonospora showed the constant presence of five phospholipids and three glycolipids. The phospholipids were identified as cardiolipids, phosphatidylethanolamine, phosphatidyl-inositol, mannosides of phosphatidyl-inositol, and possibly lysocardiolipids. The glycolipids were monoglucosyl-diglycerides, diglucosyldiglycerides (with a small amount of galactosyl-glucosyl-diglycerides) and esters of fatty acids and trehalose. The simultaneous presence of glucosyldiglycerides and trehalose esters might be specific of the genus Micromonospora . In the seven species studied, a large amount of the total fatty acids(obtained by direct saponification of the cells) consisted of iso and anteiso fatty acids. Three groups could be distinguished, having respectively iso -C 15 , iso -C 16 and n -C 17 fatty acids as the main members. A monounsaturated C 17 acid has been identified as hepatadec-9,10-enoic acid. L'analyse chromatographique des lipides de 7 espèces de Micromonospora montre la présence constante de cinq phospholipides (cardiolipides, phosphatidyl-éthanolamine, phosphatidyl-inositol et mannosides de phosphatidyl-inositol, et probablement lyso-cardiolipides), et de trois glycolipides. Ces derniers consistent en monoglucosyl-diglycérides, diglucosyl-diglycérides (avec un peu de galactosyl-glucosyl-diglycérides) et esters de tréhalose et d'acides gras. La présence simultanée de glucosides, de diglycérides et d'esters de tréhalose semble spécifique du genre Micromonospora . Les sept espèces de Micromonospora étudiées contiennent des acides gras iso et anteiso en forte proportion. Trois groupes peuvent être distingués, ayant respectivement les acides iso -C 15 , iso -C 16 et n -C 17 comme termes prépondérants. Un acide C 17 monoinsaturé a été identifié à l'acide heptadécène-9,10-oïque.

Study on neutral lipid composition of malagasy zebu fats: I. Quantitative analysis of fatty acids and sterols

AbstractThe fatty acid and sterol compositions of different parts of Malagasy zebu(Bos indicus) were evaluated. Investigation by gas liquid chromatography using Carbowax 20 M revealed 35 fatty acids, mainly palmitic (24‐27%), stearic (13‐24%), and oleic (25‐37%) acids. Odd‐numbered, iso and anteiso fatty acids were also detected. Small differences in composition were observed between the hump and the kidney fats ofB. indicus. Comparison between industrial tallow ofB. indicus andB. taurus revealed slight differences in the stearic/ oleic acid ratio (0.83 and 0.46, respectively). An OV 17 column was used to separate 9 sterols, mainly cholesterol (89‐98%).β‐Sitosterol was also found at lower concentrations in all the samples.

Acyl chains of phospholipids and their variation with age in Streptomyces griseus.

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.

The screening of beta-lactamase inhibitors: inhibition by fatty acids produced by bacteria.

An active principle inhibiting beta-lactamases, which was found in the culture of a bacillus strain was a mixture of known C14-C17 fatty acids. The mixture was separated into five components by high-performance liquid chromatography. Among these components, 12-methyltetradecanoic acid showed the strongest activity (I50: 20-146 microM). The anteiso fatty acids having the 1-methylpropyl group exhibited an interesting activity inhibiting beta-lactamases.

Metabolism of branched-chain fatty acids in Tetrahymena pyriformis W

Cultures of Tetrahymena pyriformis W were supplemented with the branched short-chain acids, isobutyrate and α-methyl- n-butyrate. Growth inhibition occurred which was directly related to the concentration of the supplement. Growth of the cells with isobutyrate resulted in an enhancement in the levels of even iso and normal fatty acids, a decrease in odd iso fatty acids, and an elevation in fatty acids less than 18 carbons in chain length. The data indicate a reduction in overall cellular branched-chain synthesis. Polyunsaturated, long-chain iso acids were not detected. Addition of α-methyl- n-butyrate led to minimal incorporation (2%) of saturated long-chain anteiso fatty acids and to a marked increase in odd normal acids at the expense of odd iso and even normal acids in the glycerophospholipids and in neutral lipids. An elevation of odd normal α-hydroxy acids in the sphingolipids was observed. The metabolism of α-methyl- n-butyrate to propionyl-CoA which serves as a primer for odd normal acids would account for the observed changes. Unsaturated anteiso components were not detected. Enhancement of the amount of anteiso acids occurred when the cells were grown at low temperature with α-methyl- n-butyrate. Long-chain anteiso acids (C 15, C 17 and C 19) were incorporated extensively into the glycerophospholipids at the expense of odd iso, odd normal and even normal acids. Anteiso unsaturates were not detected. Elongation of 15 : 0( ai) and 17 : 0(ai) occurred. Retroconversion of 17 : 0(af) and 19 : 0(ai) was observed. Growth with 17 : 0( ai) and 19 : 0( ai) but not 15 : 0( ai) led to the appearance of 19 : 0( ai, α-OH) in the sphingolipid fraction. The fact that addition of these long-chain anteiso saturates led to an enhanced incorporation into the glycerophospholipids compared to supplementation with α-methyl- n-butyrate indicates that a defect in the synthesis of long-chain acids occurs and that acyltransferase activity is not limiting in anteiso acid incorporation. A proposal is made to account for the low levels of unsaturated even iso acids and the lack of unsaturated anteiso acids based on Δ 9 desaturase specificity toward carbon chain length and the position of the methyl substituent in the fatty acid.

Lipid composition and chemotaxonomy of Pseudomonas putrefaciens (Alteromonas putrefaciens).

The major polar lipids in cells of Pseudomonas putrefaciens NCIB 10472 grown on nutrient agar were phosphatidylethanolamine, phoisphatidylglycerol, a glucosyldiacylglycerol, a glucuronosyldiacylglycerol and an ornithine amide lipid. An additional phospholipid, tentatively identified as acyl phosphatidylglycerol or bis-phosphatidic acid, was a trace component of the wall lipids from broth cultures, which lacked the glycolipids and the ornithine amide lipid. The wall lipids from broth cultures of three further strains of P. putrefaciens (NCIB 10471, NCIB 11156 and NCTC 10737) contained all of the above lipids, and in two cases (strains NCIB 10471 and NCIB 11156) had an unusually high content of free fatty acid. Fatty acid compositions of the extractable lipids were qualitatively similar for all four strains: the major components were iso-pentadecanoic acid, pentadecanoic acid, a cis-heptadecenoic acid and a cis-hexadecenoic acid. Anteiso fatty acids were minor components in strain NCIB 10472. Lipid mixtures in which the ornithine amide lipid was present also contained small amounts of beta-hydroxy fatty acids: in strain NCIB 10472 the major ones were the straight-chain and iso-branched C16 acids. Lipopolysaccharides from all four strains had similar, complex fatty acid compositions. The major non-hydroxy acids were the straight-chain and iso-branched C13 acids. beta-Hydroxy acids common to all strains included the straight-chain C11, C12, C13, C14 and C15 acids, together with branched-chain C13 and C15 acids probably belonging to the iso series. The lipopolysaccharide from strains NCIB 10472 also contained C12 and C14 hydroxy acids of the same series, and small amounts of C13 and C15 beta-hydroxy acids probably belonging to the anteiso series. The close resemblance in both polar lipid and fatty acid compositions between strains of P. putrefaciens and Pseudomonas rubescens is further evidence that these species are synonymous. Significant differences between the lipids and fatty acids of P. putrefaciens and those reported for a strain of Alteromonas haloplanktis do not harmonize with a proposal to transfer the former organism to the genus Alteromonas.

Significance and taxonomic value of iso and anteiso monoenoic fatty acids and branded beta-hydroxy acids in Desulfovibrio desulfuricans

The fatty acids obtained from extractable lipids of the anaerobic sulfate bacterium Desulfovibrio desulfuricans were identified. Saturated and monoenoic iso (C15-C19) and anteiso (C15, C17) fatty acids and saturated normal (C14-C18) and monoenoic normal (C16, C18) fatty acids were shown to be shown to be present by capillary gas chromatography-mass spectrometry. Iso and anteiso beta-hydroxy fatty acids were analyzed as trimethylsilyl ethers in the same way. The position of methyl branches in the monoenoic fatty acids was determined from characteristic fragment ions in the mass spectra of their methyl esters. Disilyloxy methyl esters, prepared by derivatization of the mono unsaturated methyl esters and analyzed by capillary gas chromatography-mass spectrometry, provided the position of double bonds. The monoenoic fatty acids identified in this way were normal (delta7-C16:1, delta9-C16:1, delta9-C18:1, delta11-C18:1), iso (delta7-C15:1, delta9-C16:1, delta9-C17:1, delta11-C18:1, delta11-C19:1), and anteiso (delta7-C15:1, delta9-C17:1). Iso delta9-C17:1 fatty acid is present as the major component. The occurrence of these monoenoic fatty acids in this bacterium is of taxonomical importance.

Mechanisms and regulation of biosynthesis of saturated fatty acids.

Mechanisms and regulation of biosynthesis of saturated fatty acids.

Analysis of fatty acid and alcoholic components of sebaceous lipid types.

Lipids were extracted from hair, scalp wipings, ovarian dermoid cysts, and vernix caseosa and submitted to alkaline hydrolysis. Alumina chromatography applied to the unsaponifiable portions allowed for the separation of hydrocarbons, alcohols, and sterols. The fatty acids from the saponifiable mixtures were converted to the methyl esters and analyzed by gas chromatography in conjunction with mass spectrometry. This technique permitted the identification of the even, odd, iso, and anteiso fatty acid levels of the various pools. Analysis of the alcohols was afforded by gas chromatography of the acetates. Ratios were determined among the acidic and alcoholic components of each lipid class and the alcoholic constituents of each pool appeared to be increased by two C2-fragments over the average carbon number of the corresponding acid fraction. Branched components ranged higher in all alcohol mixtures as compared to the respective acids and thus, indicative of a specificity for the synthesis of a specificity for the synthesis of alcohols.

The origin of fatty acids in the hydrocarbon-utilizing microorganism Mycobacterium vaccae.

The fatty acid pattern in Mycobacterium vaccae strain JOB5 was examined after growth on n-alkanes (C14-C18), 1-alkenes (C14-C18), 2- or 3-methyl octadecane, and 8-heptadecene. It was evident that monoterminal oxidation of n-alkanes was followed by beta-oxidation and that both parent fatty acid and products of beta-oxidation were incorporated into cellular lipids. Radioactive experiments demonstrated that there was desaturation of long-chain fatty acids. There was no evidence of chain elongation. Growth on 1-alkenes resulted in the incorporation of fatty acids that were products of two primary modes of oxidation: (1) methyl group attack resulting in omega-unsaturated fatty acids and (2) double-bond attack resulting in the removal of one carbon from the substrate. Cells of strain JOB5 grown on 2- and 3-methyl octadecane contained the corresponding iso- or anteiso-fatty acids in significant quantity. Cells cultured on 8-heptadecene contained 8- and 9-heptadecenoic acids, 6- and 7-pentadecenoic acids, 9- and 10-methyl heptadecanoic acids, and 7- and 8-methyl pentadecanoic acids. Fatty acid composition (C13 to C19) was affected by substrate chain length and was additionally modified by cellular control mechanisms.

Nutritional Alteration of the Fatty Acid Composition of a Thermophilic Bacillus Species

The fatty acid composition of a thermophilic Bacillus sp. was altered by the addition of isobutyrate, isovalerate, alpha-methylbutyrate, leucine, and isoleucine to the growth medium. With isobutyrate, 81% of the fatty acids had 16 carbon atoms and 79% were iso-fatty acids with an even number of carbon atoms. With leucine, 58% of the fatty acids had 15 carbon atoms and 86% were iso-fatty acids with an odd number of carbon atoms. With isoleucine, 72% of the fatty acids had 17 carbon atoms and 88% were anteiso-fatty acids with an odd number of carbon atoms. Thus, by altering the composition of the growth medium, cells were produced in which the majority of the fatty acids had either 15, 16, or 17 carbons and belonged to each of the three groups of branched-chain fatty acids. The wide variation observed in the fatty acid composition makes it unlikely that any specific branched-chain fatty acid is required for vital functions.