1763-10-6Relevant academic research and scientific papers
Substrate Recognition and Catalytic Mechanism of the Phosphate Acyltransferase PlsX from Bacillus subtilis
Jiang, Yiping,Qin, Mingming,Guo, Zhihong
, p. 2019 - 2028 (2020)
Phosphate: acyl-acyl carrier protein (ACP) acyltransferase PlsX is a peripheral enzyme catalysing acyl transfer to orthophosphate in phospholipid synthesis. Little is known about how it recognises substrates and catalyses the acyl transfer. Here we show that its active site includes many residues lining a long, narrow gorge at the dimeric interface, two positive residues forming a positive ACP docking pad next to the interfacial gorge, and a number of strictly conserved residues significantly contributing to the catalytic activity. These findings suggest a substrate recognition mode and a catalytic mechanism that are different from those of phosphotransacetylases catalysing a similar acyl transfer reaction. The catalytic mechanism involves substrate activation and transition-state stabilization by two strictly conserved residues, Lys184 and Asn229. Another noticeable feature of the catalysis is the release of the acyl phosphate product near the membrane, which might facilitate its membrane insertion.
PROCESS FOR ACYL-TRANSFER ENZYME REACTIONS WITH ACYL- COENZYME A
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, (2016/07/27)
The present invention relates to a method for acyltransferase reaction in which an acyl group of acyl coenzyme A is transferred to an acyl group receptor characterized in that the reaction is carried out by production and/or reproduction of acyl coenzyme A from coenzyme A in a reaction system by a chemical thioester exchange reaction with acylthioester. The present invention, wherein expensive acyl CoA is reproduced nonenzymatically in a reaction system, enables to continuously carry out acyltransferase reaction only by putting a small amount of acyl CoA with a donor and a receptor of an acyl group into a system. Accordingly, the method of the present invention can be applied to an industrial production method of various kinds of compounds including useful biological molecules and synthesis of polymers such as polyester.
Effect of carbon chain length in acyl coenzyme A on the efficiency of enzymatic transformation of okadaic acid to 7-O-acyl okadaic acid
Furumochi, Sachie,Onoda, Tatsuya,Cho, Yuko,Fuwa, Haruhiko,Sasaki, Makoto,Yotsu-Yamashita, Mari,Konoki, Keiichi
supporting information, p. 2992 - 2996 (2016/06/13)
Okadaic acid (OA), a product of dinoflagellate Prorocentrum spp., is transformed into 7-O-acyl OA in various bivalve species. The structural transformation proceeds enzymatically in vitro in the presence of the microsomal fraction from the digestive gland of bivalves. We have been using LC-MS/MS to identify OA-transforming enzymes by detecting 7-O-acyl OA, also known as dinophysistoxin 3 (DTX3). However, an alternative assay for DTX3 is required because the OA-transforming enzyme is a membrane protein, and surfactants for solubilizing membrane proteins decrease the sensitivity of LC-MS/MS. The present study examined saturated fatty acyl CoAs with a carbon chain length of 10 (decanoyl), 12 (dodecanoyl), 14 (tetradecanoyl), 16 (hexadecanoyl) and 18 (octadecanoyl) as the substrate for the in vitro acylation reaction. Saturated fatty acyl CoAs with a carbon chain length of 14, 16 and 18 exhibited higher yields than those with a carbon chain length of 10 or 12. Acyl CoAs with carbon chain lengths from 14 to 18 and containing either a diene unit, an alkyne unit, or an azide unit in the carbon chain were synthesized and shown to provide the corresponding DTX3 with a yield comparable to that of hexadecanoyl CoA. The three functional units can be conjugated with fluorescent reagents and are applicable to the development of a novel assay for DTX3.
Enantiodifferentiation of ketoprofen by Japanese firefly luciferase from Luciola lateralis
Kato, Dai-Ichiro,Tatsumi, Tomohiro,Bansho, Asami,Teruya, Keisuke,Yoshida, Hiromitsu,Takeo, Masahiro,Negoro, Seiji
experimental part, p. 140 - 146 (2012/01/19)
Recently, we found that firefly luciferase exhibited (R)-enantioselective thioesterification activity toward 2-arylpropanoic acids. In the case of Japanese firefly luciferase from Luciola lateralis (LUC-H), the E-value for ketoprofen was approximately 20. In this study, we used a spectrophotometric method to measure the catalytic activity of LUC-H. Using this method allowed us to judge the reaction efficiency easily. Our results confirmed that LUC-H exhibits enantioselective thioesterification activity toward a series of 2-arylpropanoic acids. The highest activity was observed with ketoprofen. We also observed high enzymatic activity of LUC-H toward long-chain fatty acids. These results were reasonable because LUC-H is homologous with long-chain acyl-CoA synthetase. To obtain further information about the enantiodifferentiation mechanism of the LUC-H catalyzed thioesterification of ketoprofen, we determined the kinetic parameters of the reaction relative to each of its three substrates: ketoprofen, ATP, and coenzyme A (CoASH). We found that whereas the affinities of each compound are not affected by the chirality of ketoprofen, enantiodifferentiation is achieved by a chirality-dependent difference in the kcat parameter.
Comparison of acyl-CoA synthetic activities and enantioselectivity toward 2-arylpropanoic acids in firefly luciferases
Kato, Dai-Ichiro,Yokoyama, Keisuke,Hiraishi, Yoshihiro,Takeo, Masahiro,Negoro, Seiji
experimental part, p. 1758 - 1762 (2012/02/02)
Measurement of thioesterification activities for dodecanoic acid (C12) and ketoprofen was done using five firefly luciferases, from Pyrocoelia miyako (PmL), Photinus pyralis (PpL), Luciola cruciata (LcL), Hotaria parvura (HpL), and Luciola mingrelica (LmL). Among these, PmL, PpL, and LcL showed the expected thioesterification activities toward both substrates. All the enzymes exhibited (R)-enantioselectivity toward ketoprofen, which had same tendency as firefly luciferase from Luciola lateralis (LUC-H). HpL and LmL, however, did not accept ketoprofen, although they had thioesterification activity toward C12. These results indicate that the substrate acceptance of luciferases for the thioesterification reaction varies dramatically relying on the origin of firefly. Hence we focused primarily on PmL and investigated the effect of pH on enzymatic activity. In addition, by determining the kinetic parameters at various pH values, we verified that the kcat parameter contributed to the preferential enantioselectivity of this enzyme.
