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Anteiso-branched chain fatty acids

Fig. 21.15. Partial gas chromatogram of extracted lipids. Peaks Ci4 0 to Ci8 o> saturated straight fatty chain acids (FA) with 14 to 18 carbon atoms C45br and Ci7 r, iso- and anteiso- branched-chain fatty acids Ci8 i FA, mono-unsatu-rated CigtoOH-FA, hydroxylated form derived by bacterial hydration of the original oleic acid. (Reprinted/redrawn from Nature, 432, 35-36, Copyright 2004, Nature Publishing Group, with permission.)... Fig. 21.15. Partial gas chromatogram of extracted lipids. Peaks Ci4 0 to Ci8 o> saturated straight fatty chain acids (FA) with 14 to 18 carbon atoms C45br and Ci7 r, iso- and anteiso- branched-chain fatty acids Ci8 i FA, mono-unsatu-rated CigtoOH-FA, hydroxylated form derived by bacterial hydration of the original oleic acid. (Reprinted/redrawn from Nature, 432, 35-36, Copyright 2004, Nature Publishing Group, with permission.)...
Other bacteria use different systems to regulate fluidity. For example, gram-positive bacteria alter the ratio of iso- to anteiso-branched-chain fatty acids in response to temperature [20]. However, the biochemical mechanisms that govern this universal response to environmental temperature are largely unknown in most bacterial species. [Pg.87]

Compound C. The mass spectrum again showed the common anacardic acid ions, and a molecular ion of m/z 362, which suggested that Compound C was a C21 saturated anacardic acid. The nmr spectrum also indicated that C was saturated, and the terminal methyl signal at 80.85ppm was complexed and represented 6 protons. Hence C was identified as a C21 branched chain anacardic acid, and by comparison with the nmr spectra of iso and anteiso branched chain fatty acid standards, the terminal methyl signal was identical to the terminal methyl resonance of an anteiso group, thus C is in all probability the C21 anteiso saturated anacardic acid. [Pg.235]

Figure 3.8 Production of an anteiso branched chain fatty acid in bacteria. Figure 3.8 Production of an anteiso branched chain fatty acid in bacteria.
Massart-Leen et al. (1981) analyzed bovine milk fat and goat milk fat for branched chain fatty acids. They did not find the same diversity of fatty acids in bovine as in goat milk fat and as previously reported. The authors suggested that the difference—the absence of branched chain acids other than iso and anteiso in bovine milk fat—could be caused by the relative inefficiency of the incorporations of methylmalonic acid into the biosynthetic pathway. [Pg.191]

Branched-chain fatty acids (BrFAs) (iso- and anteiso) are believed to be primarily derived from sulfate-reducing bacteria (Perry et al., 1979 Cranwell, 1982 Canuel et al., 1995 table 9.5). However, it should be noted that BrFAs are not present in all sulfate-reducing bacteria or other heterotrophic bacteria (Kaneda, 1991 Kohring et al., 1994). The iso- and antesio- designation represents a branched fatty acid with the methyl group at the a>-l position and the methyl group at the a>-2 position, respectively. The odd number (C45, C17, branched and normal) are believed to be derived from phospholipids, components of bacterial cell membranes (Kaneda, 1991). Even-numbered iso-branched fatty acids (e.g., C12—Cig) are also found in algal sources (Schnitzer and Khan, 1972). [Pg.247]

Linear capsiacinoids with a C9/C12 chain are only trace constituents of capsicum oleoresin, which mainly contains branched capsaicinoids. The acyl moiety of these compounds is produced by the branched chain fatty acids pathway (Scheme 4.1) [30[. Depending on the nature of the amino acid that acts as the acyl starter precursor, different capsaicinoids are formed. Thus, capsaicinoids of the iso series such as CPS and homocapsaicin I are derived from valine and leucine via isobutyrylCoA and isovalerylCoA, respectively, while those from the anteiso series such as homocapsaicin II originate from isoleucine via 2-methylbutyrylCoA (Scheme 4.1) [31[. The polymethylene moiety of norcapsaicin has one less carbon than capsaicin. The... [Pg.80]

One striking thing to note from the structures of the branched chain compounds is the fact that the C21, C23 and C25 branched chain anacardic acids are all anteiso, and the C22 and C24 branched compounds are iso. At this point in the work it is not clear why this should be the case, but the findings would suggest that odd chain length and even chain length branched chain fatty acids are synthesized from different precursors. [Pg.248]

It is relatively rare to find significant quantities of both odd chain length and branched chain fatty acids in biological systems. However such compounds have been Isolated and identified from the epicuticular wax from Brussels sprout leaves, with anteiso-C j and anteiso-C making up 36% of the total saturated fatty acid fraction (13). Similarly Radunz has isolated and identified iso and anteiso mono methyl branched fatty acids in phospholipids, contained in yellow-white leaves and petals of the plastome mutants "Prasinizans" of Antirrhinum majus and "Xanthr of Nicotiana tabacum M4T In addition small amounts of odd chain length fatty acids and alcohols have been found in the surface waxes of Zea mays husks (15). [Pg.248]

The fatty acid synthetase of Brevibacterium ammoniagenes has a high molecular weight (like Type I synthetases) but produces both saturated and unsaturated acids (like E, coli Type II synthetase). In most Gram-positive and some Gram-negative bacteria, branched-chain fatty acids predominate. These branched-chain acids are made by Type II synthetases that use short-chain branched acyl-CoA primers instead of acetyl-CoA and so produce iso or anteiso fatty acid products (Kaneda, 1977). [Pg.488]

In most bacterial species C15 fatty acids are present in trace amounts, so their elevated levels (2-3 times higher than any other fatty acid) in propionibacteria can serve as a diagnostic marker. However, this marker should be taken with caution, since the levels of free fatty acids in bacteria depend on media composition, age of culture and the level of vitamin B12 in the cells. Addition of isoleucine to die medium increases the synthesis of anteiso-C s acid by propionibacteria. In the presence of L-leucine they produce more / o-Ci5 acid by decreasing anteiso-C s acid (Moss et al., 1969). In the cells of young active cultures usually the level of straight-chain mono-unsaturated acids (Cie i, Cis i) is higher. The content of mono-unsaturated fatty acids is higher than the branched-chain fatty acids in cultures deficient in vitamin B12. With the cell free extract of C simplex it was shown that vitamin B12 deficit leads to a decrease in the activity of transmethylase system and in the rate of the transformation of mono-unsaturated acids to CHs-branched fatty acids (Fujii and Fukui, 1969). A distinct fatty acid composition was found (Kusano et al., 1997) in P. cyclohexanicum. The major fatty acid was o-cyclohexyl undecanoic acid, while iso- and anteiso-C s, C16, and Cn fatty acids were also present, but in a small amount. [Pg.22]

Branched-chain fatty acids occur widely in nature, but tend to be present as minor components except in bacteria, where they appear to replace unsaturated fatty acids functionaiiy. Usually, the branch consists of a single methyl group, either on the penultimate (/so) or antepenultimate (anteiso) carbon atoms (Figure 2.2). In the biosynthesis of these fatty acids, the primer molecules for chain-elongation by the fatty acid synthetase are 2-methylpropanoic and 2-methylbutanoic acids, respectively. Methyl branches can be found in other positions of the chain (on even-numbered carbon atoms), if methylmalonyl-coenzyme A rather than malonyl-coenzyme A is used in for chain extension this can occur in bacteria and in animal tissues, especially those of ruminant animals, where polymethyl-branched fatty acids even can be synthesised [275]. [Pg.9]

Mono-methyl branched fatty acids of the iso- and anteiso types with chain lengths of 12 to 22 carbon atoms were found in yellow-white leaves and petals of the plastome mutants "Prasinizans" of Antirrhinum majus and "Xanthi"ot Nicotiana tabacum. These branched chain fatty acids are preponderantly esterified in the sn-2 position of the glycerol backbone of the membrane phospholipids namely phosphatidylcholine, phosphatidyletha-nolamine and phosphatidylinositol. The phospholipids appear to contain 16-24 per cent iso- and anteiso fatty acids, 19-47 per cent unsaturated and 38-63 per cent saturated fatty acids. The methyl-branched chain fatty acids seem to take over the function of the unsaturated fatty acids. [Pg.197]

Many substituted, ie, branched, fatty acids, particularly methacryUc, 2-ethylhexanoic, and ricinoleic acids, are commercially significant. Several substituted fatty acids exist naturally (Table 5). Fatty acids with a methyl group in the penultimate position are called iso acids, and those with a methyl group in the antepenultimate position are called anteiso acids (1) (see Carboxylic acids, branched-CHAIN acids). However, the term iso is often used in a broader sense to mean branched or mixtures of branched-chain industrial acids. [Pg.80]

The basic fish oil (27) also included a generous amount of saturated fatty acids. As can be seen from Figure 5 and Table 1, the saturated fatty acids are dominated by the 16 0 (palmitic acid), usually accompanied by about half as much or less of 14 0 (myristic acid) and much less of 18 0 (stearic acid). Usually the saturated fatty acid totals are at least 20%, especially as the odd chain (15 0, 17 0) and methyl-branched (iso, anteiso, pristanic, phytanic) fatty acids (compare Figure 4) are sam-rated and will total around 2-3%. An unsaturated peak that is often observed is 17 ln-8, which is roughly equal to 17 0. The details of these peaks are discussed in other publications, but those researchers attempting modern open-tubular gas chromatography analyses should be aware of their presence and influence on peak identification and quantitation. As can be seen from Figure 6, there is an... [Pg.1650]

Two major types of BCFAs occur in nature iso series and anteiso series [2]. Anteiso-15 0, having methyl branching at antepenultimate positions (anteiso), showed cytotoxicity comparable to that of iso-15 0 [7]. Thus, the Djq of both iso-15 0 and anteiso-15 0 were lower than those of corresponding straight-chain fatty acids. [Pg.260]

Tetrahydrogenated menaquinones with nine isoprene units, i.e. MQ-9(H4) are the major respiratory quinones. Long-chain fatty acids are of the straight-chain saturated and iso- and anteiso-mQthyl branched-chain types (12- or 13-... [Pg.42]

The discovery of a novel pathway for biosynthesis of medium and short chain fatty acids in plants (a-keto acid elongation pathway, 1) raises the possibility (however unlikely) that medium-chain fatty acids (mcFAs) of certain oil seeds producing them may be derived by this pathway. Alternatively, these may be formed after release of elongating fatty acid chains from fatty acid synthase mediated biosynthesis (FAS) by specific medium chain thioesterases [2, 3,4]. Thus far the aKAE pathway is only known to occur in trichome glands of plants in the family Solanaceae. In the aKAE pathway, iso-, anteiso- or straight-chain keto acid products of branched-chain amino acid metabolism are elongated by one carbon (via acetate) per cycle. The final step is predicted to be oxidative decarboxylation to yield CoA activated acids. The mechanism that determines the chain length of aKAE products is not understood [1]. [Pg.54]

Marinobacter hydrocarbonoclasticus Sediment Mediterranean Sea Branched iso and anteiso P-hydroxy long-chain fatty acids Antibiotics Gauthier et a/., 1992 Lattuati etai, 2002 Aubert, Metzger, and Largeau, 2004 Soltani, Metzger, and Largeau, 2004... [Pg.116]

Chemical examination of the sea cucumber Holothuria leucospilota led to the isolation of a phytosphingosine-type glucocerebroside (40) with a 2-hydroxylated fatty acid of 22 carbons and an anteiso type side chain in the base moiety (Fig. 12) [55]. The absolute configuration of the branched methyl group was determined by release of a C13 fragment of the native cere-broside and further reduction to 10-methyl dodecanol. The absolute configuration of the natural alcohol was elucidated by comparison with synthetic optically active 10-methyl dodecanol synthesized from 1,4-butanediol [56]. [Pg.73]


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Anteiso-acids

Anteiso-branched fatty acids

Branched chain

Branched-chain acids

Branched-chain fatty acids

Chain branching

Fatty acid anteiso

Fatty acid branched

Fatty acid branches

Fatty acid chains

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