Biosynthesis of branched-chain fatty acids in Bacillus subtilis. A decarboxylase is essential for branched-chain fatty acid synthetase.

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 > propionyl-CoA [Formula: see text] 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.

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A lipA (yutB) Mutant, Encoding Lipoic Acid Synthase, Provides Insight into the Interplay between Branched-Chain and Unsaturated Fatty Acid Biosynthesis in Bacillus subtilis

Journal of Bacteriology ◽

10.1128/jb.01160-09 ◽

2009 ◽

Vol 191 (24) ◽

pp. 7447-7455 ◽

Cited By ~ 17

Author(s):

Natalia Martin ◽

Esteban Lombardía ◽

Silvia G. Altabe ◽

Diego de Mendoza ◽

María C. Mansilla

Keyword(s):

Fatty Acids ◽

Bacillus Subtilis ◽

Fatty Acid ◽

Lipoic Acid ◽

Unsaturated Fatty Acids ◽

Membrane Properties ◽

Δ5 Desaturase ◽

Branched Chain Fatty Acids ◽

Branched Chain ◽

Chain Fatty Acids

ABSTRACT Lipoic acid is an essential cofactor required for the function of key metabolic pathways in most organisms. We report the characterization of a Bacillus subtilis mutant obtained by disruption of the lipA (yutB) gene, which encodes lipoyl synthase (LipA), the enzyme that catalyzes the final step in the de novo biosynthesis of this cofactor. The function of lipA was inferred from the results of genetic and physiological experiments, and this study investigated its role in B. subtilis fatty acid metabolism. Interrupting lipoate-dependent reactions strongly inhibits growth in minimal medium, impairing the generation of branched-chain fatty acids and leading to accumulation of copious amounts of straight-chain saturated fatty acids in B. subtilis membranes. Although depletion of LipA induces the expression of the Δ5 desaturase, controlled by a two-component system that senses changes in membrane properties, the synthesis of unsaturated fatty acids is insufficient to support growth in the absence of precursors for branched-chain fatty acids. However, unsaturated fatty acids generated by deregulated overexpression of the Δ5 desaturase functionally replaces lipoic acid-dependent synthesis of branched-chain fatty acids. Furthermore, we show that the cold-sensitive phenotype of a B. subtilis strain deficient in Δ5 desaturase is suppressed by isoleucine only if LipA is present.

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Properties of Acetate Kinase Isozymes and a Branched-Chain Fatty Acid Kinase from a Spirochete

Journal of Bacteriology ◽

10.1128/jb.152.1.246-254.1982 ◽

1982 ◽

Vol 152 (1) ◽

pp. 246-254

Author(s):

Caroline S. Harwood ◽

Ercole Canale-Parola

Keyword(s):

Amino Acids ◽

Fatty Acids ◽

Molecular Weight ◽

Fatty Acid ◽

Branched Chain Amino Acids ◽

Chain Fatty Acid ◽

Acetate Kinase ◽

Nucleoside Triphosphate ◽

Branched Chain ◽

Chain Fatty Acids

Spirochete MA-2, which is anaerobic, ferments glucose, forming acetate as a major product. The spirochete also ferments (but does not utilize as growth substrates) small amounts of l -leucine, l -isoleucine, and l -valine, forming the branched-chain fatty acids isovalerate, 2-methylbutyrate, and isobutyrate, respectively, as end products. Energy generated through the fermentation of these amino acids is utilized to prolong cell survival under conditions of growth substrate starvation. A branched-chain fatty acid kinase and two acetate kinase isozymes were resolved from spirochete MA-2 cell extracts. Kinase activity was followed by measuring the formation of acyl phosphate from fatty acid and ATP. The branched-chain fatty acid kinase was active with isobutyrate, 2-methylbutyrate, isovalerate, butyrate, valerate, or propionate as a substrate but not with acetate as a substrate. The acetate kinase isozymes were active with acetate and propionate as substrates but not with longer-chain fatty acids as substrates. The acetate kinase isozymes and the branched-chain fatty acid kinase differed in nucleoside triphosphate and cation specificities. Each acetate kinase isozyme had an apparent molecular weight of approximately 125,000, whereas the branched-chain fatty acid kinase had a molecular weight of approximately 76,000. These results show that spirochete MA-2 synthesizes a branched-chain fatty acid kinase specific for leucine, isoleucine, and valine fermentation. It is likely that a phosphate branched-chain amino acids is also synthesized by spirochete MA-2. Thus, in spirochete MA-2, physiological mechanisms have evolved which serve specifically to generate maintenance energy from branched-chain amino acids.

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Effect of Rearing System on the Straight and Branched Fatty Acids of Goat Milk and Meat of Suckling Kids

Foods ◽

10.3390/foods9040471 ◽

2020 ◽

Vol 9 (4) ◽

pp. 471

Author(s):

Guillermo Ripoll ◽

María Jesús Alcalde ◽

Anastasio Argüello ◽

María de Guía Córdoba ◽

Begoña Panea

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Goat Milk ◽

Lower Percentage ◽

Dairy Goat ◽

Branched Chain Fatty Acids ◽

Branched Chain ◽

Milk Replacers ◽

Fatty Acid Compositions ◽

Chain Fatty Acids

Goat meat is considered healthy because it has fewer calories and fat than meat from other traditional meat species. It is also rich in branched chain fatty acids that have health advantages when consumed. We studied the effects of maternal milk and milk replacers fed to suckling kids of four breeds on the straight and branched fatty acid compositions of their muscle. In addition, the proximal and fatty acid compositions of colostrum and milk were studied. Goat colostrum had more protein and fat and less lactose than milk. Goat milk is an important source of healthy fatty acids such as C18:1 c9 and C18:2 n–6. Suckling kid meat was also an important source of C18:1c9. Dairy goat breeds had higher percentages of trans monounsaturated fatty acids (MUFAs) and most of the C18:1 isomers but lower amounts of total MUFAs than meat breeds. However, these dairy kids had meat with a lower percentage of conjugated linoleic acid (CLA) than meat kids. The meat of kids fed natural milk had higher amounts of CLA and branched chain fatty acids (BCFAs) and lower amounts of n–6 fatty acids than kids fed milk replacers. Both milk and meat are a source of linoleic, α-linolenic, docosahexaenoic, eicosapentaenoic and arachidonic fatty acids, which are essential fatty acids and healthy long-chain fatty acids.

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Incorporation of branched-chain C6-fatty acid isomers into the related long-chain fatty acids by growing cells of Bacillus subtilis

Biochemistry ◽

10.1021/bi00778a022 ◽

1971 ◽

Vol 10 (2) ◽

pp. 340-347 ◽

Cited By ~ 15

Author(s):

Toshi Kaneda

Keyword(s):

Fatty Acids ◽

Bacillus Subtilis ◽

Fatty Acid ◽

Long Chain Fatty Acids ◽

Branched Chain ◽

Long Chain ◽

Chain Fatty Acids

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Relationship of primer specificity of fatty acid de novo synthetase to fatty acid composition in 10 species of bacteria and yeasts

Canadian Journal of Microbiology ◽

10.1139/m80-155 ◽

1980 ◽

Vol 26 (8) ◽

pp. 893-898 ◽

Cited By ~ 27

Author(s):

Toshi Kaneda ◽

E. J. Smith

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Chain Length ◽

De Novo ◽

Micrococcus Luteus ◽

Straight Chain ◽

Acetyl Coa ◽

Branched Chain Fatty Acids ◽

Branched Chain ◽

Chain Fatty Acids

Fatty acid compositions of lipids from six bacteria and four yeasts were determined. Fatty acid de novo synthetases were investigated with respect to chain length specificity towards acyl-CoA primers of various chain lengths.Four species of bacteria (Bacillus subtilis, Corynebacterium cyclohexanicum, Micrococcus luteus, and Pseudomonas maltophilia) possess branched-chain fatty acids of the iso and anteiso series as the major acids. De novo synthetases from these organisms exhibited specificity towards the chain length of the primer in the order butyrl-CoA > propionyl-CoA [Formula: see text] acetyl-CoA. The remainder, two bacteria and all four yeasts, have the straight-chain type of fatty acids only and fall into two groups: (1) Eschericia coli B, Pseudomonas fluorescens, and Saccharomyces cerevisiae, which utilize the primers in the order acetyl-CoA > propionyl-CoA [Formula: see text] butyryl-CoA; and (2) Candida sake, Candida tropicalis, and Rhodolorula glutinis, which show the order propionyl-CoA > acetyl-CoA [Formula: see text] butyryl-CoA.L-α-Keto-β-methylvalerate, a precursor of the branched-chain primers, can be used as a source of primer for fatty acid synthesis by the organisms with branched-chain acids but not by those with the straight-chain type.The results indicate that organisms having straight-chain fatty acids lack the branched-chain equivalents for two reasons: first, their enzymes are not active toward primers with more than three carbons, and second, they lack a system of supplying suitable branched-chain primers.It appears that activities of de novo synthetases from the organisms having straight-chain fatty acids generally have much higher activities than those from the organisms possessing branched-chain fatty acids.

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Variation of Branched-Chain Fatty Acids Marks the Normal Physiological Range for Growth in Listeria monocytogenes

Applied and Environmental Microbiology ◽

10.1128/aem.68.6.2809-2813.2002 ◽

2002 ◽

Vol 68 (6) ◽

pp. 2809-2813 ◽

Cited By ~ 30

Author(s):

David S. Nichols ◽

Kirsty A. Presser ◽

June Olley ◽

Tom Ross ◽

Tom A. McMeekin

Keyword(s):

Fatty Acids ◽

Fatty Acid Composition ◽

Fatty Acid ◽

Listeria Monocytogenes ◽

Acid Composition ◽

Physiological Range ◽

Branched Chain Fatty Acids ◽

Branched Chain ◽

High Degree ◽

Chain Fatty Acids

ABSTRACT The fatty acid composition of Listeria monocytogenes Scott A was determined by close-interval sampling over the entire biokinetic temperature range. There was a high degree of variation in the percentage of branched-chain fatty acids at any given temperature. The percentage of branched C17 components increased with growth temperature in a linear manner. However, the percentages of iso-C15:0 (i15:0) and anteiso-C15:0 (a15:0) were well described by third-order and second-order polynomial curves, respectively. There were specific temperature regions where the proportion of branched-chain fatty acids deviated significantly from the trend established over the entire growth range. In the region from 12 to 13°C there were significant deviations in the percentages of both i15:0 and a15:0 together with a suggested deviation in a17:0, resulting in a significant change in the total branched-chain fatty acids. In the 31 to 33°C region the percentage of total branched-chain components exhibited a significant deviation. The observed perturbations in fatty acid composition occurred near the estimated boundaries of the normal physiological range for growth.

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