Publications

• An acyl-CoA synthetase in Mycobacterium tuberculosis involved in triacylglycerol accumulation during dormancy.

  Daniel J., Sirakova T., Kolattukudy P.

  Latent infection with dormant Mycobacterium tuberculosis is one of the major reasons behind the emergence of drug-resistant strains of the pathogen worldwide. In its dormant state, the pathogen accumulates lipid droplets containing triacylglycerol synthesized from fatty acids derived from host lip ... >> More

  Latent infection with dormant Mycobacterium tuberculosis is one of the major reasons behind the emergence of drug-resistant strains of the pathogen worldwide. In its dormant state, the pathogen accumulates lipid droplets containing triacylglycerol synthesized from fatty acids derived from host lipids. In this study, we show that Rv1206 (FACL6), which is annotated as an acyl-CoA synthetase and resembles eukaryotic fatty acid transport proteins, is able to stimulate fatty acid uptake in E. coli cells. We show that purified FACL6 displays acyl-coenzyme A synthetase activity with a preference towards oleic acid, which is one of the predominant fatty acids in host lipids. Our results indicate that the expression of FACL6 protein in Mycobacterium tuberculosis is significantly increased during in vitro dormancy. The facl6-deficient Mycobacterium tuberculosis mutant displayed a diminished ability to synthesize acyl-coenzyme A in cell-free extracts. Furthermore, during in vitro dormancy, the mutant synthesized lower levels of intracellular triacylglycerol from exogenous fatty acids. Complementation partially restored the lost function. Our results suggest that FACL6 modulates triacylglycerol accumulation as the pathogen enters dormancy by activating fatty acids. << Less

  PLoS ONE 9:e114877-e114877(2014) [PubMed] [EuropePMC]

  This publication is cited by 2 other entries.

• Jasmonates meet fatty acids: functional analysis of a new acyl-coenzyme A synthetase family from Arabidopsis thaliana.

  Kienow L., Schneider K., Bartsch M., Stuible H.-P., Weng H., Miersch O., Wasternack C., Kombrink E.

  Arabidopsis thaliana contains a large number of genes encoding carboxylic acid-activating enzymes, including long-chain fatty acyl-CoA synthetase (LACS), 4-coumarate:CoA ligases (4CL), and proteins closely related to 4CLs with unknown activities. The function of these 4CL-like proteins was systema ... >> More

  Arabidopsis thaliana contains a large number of genes encoding carboxylic acid-activating enzymes, including long-chain fatty acyl-CoA synthetase (LACS), 4-coumarate:CoA ligases (4CL), and proteins closely related to 4CLs with unknown activities. The function of these 4CL-like proteins was systematically explored by applying an extensive substrate screen, and it was uncovered that activation of fatty acids is the common feature of all active members of this protein family, thereby defining a new group of fatty acyl-CoA synthetase, which is distinct from the known LACS family. Significantly, four family members also displayed activity towards different biosynthetic precursors of jasmonic acid (JA), including 12-oxo-phytodienoic acid (OPDA), dinor-OPDA, 3-oxo-2(2'-[Z]-pentenyl)cyclopentane-1-octanoic acid (OPC-8), and OPC-6. Detailed analysis of in vitro properties uncovered significant differences in substrate specificity for individual enzymes, but only one protein (At1g20510) showed OPC-8:CoA ligase activity. Its in vivo function was analysed by transcript and jasmonate profiling of Arabidopsis insertion mutants for the gene. OPC-8:CoA ligase expression was activated in response to wounding or infection in the wild type but was undetectable in the mutants, which also exhibited OPC-8 accumulation and reduced levels of JA. In addition, the developmental, tissue- and cell-type specific expression pattern of the gene, and regulatory properties of its promoter were monitored by analysing promoter::GUS reporter lines. Collectively, the results demonstrate that OPC-8:CoA ligase catalyses an essential step in JA biosynthesis by initiating the beta-oxidative chain shortening of the carboxylic acid side chain of its precursors, and, in accordance with this function, the protein is localized in peroxisomes. << Less

  J. Exp. Bot. 59:403-419(2008) [PubMed] [EuropePMC]

  This publication is cited by 15 other entries.

• Human liver-specific very-long-chain acyl-coenzyme A synthetase: cDNA cloning and characterization of a second enzymatically active protein.

  Steinberg S.J., Wang S.J., McGuinness M.C., Watkins P.A.

  Activation of fatty acids, catalyzed by acyl-coenzyme A (acyl-CoA) synthetases, is required for their subsequent metabolism. Peroxisomes and microsomes contain very-long-chain acyl-CoA synthetases (VLCSs) capable of activating fatty acids with a chain length of 22 or more carbons. Decreased peroxi ... >> More

  Activation of fatty acids, catalyzed by acyl-coenzyme A (acyl-CoA) synthetases, is required for their subsequent metabolism. Peroxisomes and microsomes contain very-long-chain acyl-CoA synthetases (VLCSs) capable of activating fatty acids with a chain length of 22 or more carbons. Decreased peroxisomal VLCS activity is, in part, responsible for the biochemical pathology in X-linked adrenoleukodystrophy (X-ALD), illustrating the importance of VLCSs in cellular fatty acid homeostasis. We previously cloned two human genes encoding proteins homologous to rat peroxisomal VLCS; one (hVLCS) is the human ortholog to the rat VLCS gene and another (hVLCS-H1) encodes a related heart-specific protein. Here, we report the cloning of a third gene (hVLCS-H2) and characterization of its protein product. The hVLCS-H2 gene is located on human chromosome 19 and encodes a 690-amino-acid protein. The amino acid sequence of hVLCS-H2 is 44-45% identical and 67-69% similar to those of both hVLCS and hVLCS-H1. COS-1 cells transiently overexpressing hVLCS-H2 activated the very-long-chain fatty acid lignocerate (C24:0) at a rate >1.5-fold higher than that of nontransfected cells (P < 0.002). The hVLCS-H2-dependent activation of long- and branched-chain fatty acids following transient transfection was less striking. However, hVLCS-H2-dependent acyl-CoA synthetase activity with long- and very-long-chain fatty acid substrates was detected in COS-1 cells stably expressing hVLCS-H2. For all substrates tested (C18:0, C20:0, C24:0, C26:0), the hVLCS-H2 catalyzed activity was significantly increased (P < 0.01 to P < 0.0001). By both Northern analysis and reverse transcription polymerase chain reaction, hVLCS-H2 is expressed primarily in liver. Indirect immunofluorescence of COS-1 cells or human hepatoma-derived HepG2 cells expressing epitope-tagged hVLCS-H2 revealed that the protein was associated with the endoplasmic reticulum but not with peroxisomes. Thus, the primary role of hVLCS-H2 is likely to be in fatty acid elongation or complex lipid synthesis rather than in degradation. << Less

  Mol. Genet. Metab. 68:32-42(1999) [PubMed] [EuropePMC]

  This publication is cited by 3 other entries.

• Biochemical studies of three Saccharomyces cerevisiae acyl-CoA synthetases, Faa1p, Faa2p, and Faa3p.

  Knoll L.J., Johnson D.R., Gordon J.I.

  The efficiency and specificity of protein N-myristoylation appear to be influenced by the availability of myristoyl-CoA and other potential acyl-CoA substrates of myristoyl-CoA:protein N-myristoyltransferase. Recent studies have revealed that Saccharomyces cerevisiae contains at least three acyl-C ... >> More

  The efficiency and specificity of protein N-myristoylation appear to be influenced by the availability of myristoyl-CoA and other potential acyl-CoA substrates of myristoyl-CoA:protein N-myristoyltransferase. Recent studies have revealed that Saccharomyces cerevisiae contains at least three acyl-CoA synthetase genes (FAA for fatty acid activation). We have expressed Faa1p, Faa2p, and Faa3p in a strain of Escherichia coli that lacks its own endogenous acyl-CoA synthetase (FadD). Each S. cerevisiae acyl-CoA synthetase contained a carboxyl-terminal His tag so that it could be purified to homogeneity in a single step using nickel chelate affinity chromatography. In vitro assays of C3:0-C24:0 fatty acids indicate that Faa1p prefers C12:0-C16:0, with myristic and pentadecanoic acid (C15:0) having the highest activities. Faa2p can accommodate a wider range of acyl chain lengths: C9:0-C13:0 are preferred and have equivalent activities, although C7:0-C17:0 fatty acids are tolerated as substrates with no greater than a 2-fold variation in specific activity. The myristoyl-CoA synthetase activities of Faa1p and Faa2p are 2 orders of magnitude greater than that of Faa3p in vitro. Faa3p has a preference for C16 and C18 fatty acids with a cis-double bond at C-9-C-10. The temperature optimum for Faa1p is 30 degrees C, while Faa2p and Faa3p have the greatest activities at 25 degrees C. These in vitro observations were confirmed using two in vivo assays: (i) measurement of the ability of each S. cerevisiae acyl-CoA synthetase to direct the incorporation of exogenously derived tritiated myristate, palmitate, or oleate into cellular phospholipids produced in a fadD-strain of E. coli during exponential growth at 24 or 37 degrees C and (ii) measurement of the incorporation of [3H]myristate into a yeast N-myristoylprotein coexpressed with Nmt1p and Faa1p, Faa2p, or Faa3p in the fadD-strain. << Less

  J. Biol. Chem. 269:16348-16356(1994) [PubMed] [EuropePMC]

  This publication is cited by 19 other entries.