Redesign of cosubstrate specificity and identification of important residues for substrate binding to hChAT.


:In eukaryotes, choline acetyltransferase (ChAT) catalyzes the reversible formation of the neurotransmitter acetylcholine from choline and acetyl-CoA. ChAT belongs to a family of CoA-dependent enzymes that also includes the carnitine acyltransferases CrAT, CrOT, and CPTs. In contrast to CrOT and CPTs that are very active toward medium- and long-chain acyl-CoAs, respectively, CrAT and ChAT display activity toward only short-chain acyl-CoAs. We recently demonstrated the substrate and cosubstrate promiscuity of the wild-type human ChAT (hChAT). To extend the flexibility of this enzyme, we have generated a series of single, double, and triple hChAT mutants. Here we report the conversion of hChAT into choline octanoyltransferase (ChOT) and choline palmitoyltransferase (ChPT). The E337 and C550 residues (numbering from hChAT) were previously shown to dictate the acyl-CoA cosubstrate specificity in the carnitine series. Here we identify and demonstrate the importance of C551, in addition to E337 and C550, in contributing to the acyl-CoA specificity of hChAT. We also show that either C550 or C551 needs to be present for the transfer of medium- and long-chain acyl-CoAs by hChAT. By exploring the potential expansion of the tunnel on the substrate side, we demonstrate that residues M84, Y436, and Y552 play a critical role in binding and holding the choline substrate in the ChAT active site.






Green KD,Porter VR,Zhang Y,Garneau-Tsodikova S




Has Abstract


2010-07-27 00:00:00












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    pub_type: 杂志文章


    authors: Butcher DJ,Nedved ML,Neiss TG,Moe GR

    更新日期:1996-01-23 00:00:00

  • DNA damage and cytotoxicity induced by minor groove binding methyl sulfonate esters.

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    pub_type: 杂志文章


    authors: Varadarajan S,Shah D,Dande P,Settles S,Chen FX,Fronza G,Gold B

    更新日期:2003-12-09 00:00:00

  • Structure of human transferrin receptor oligosaccharides: conservation of site-specific processing.

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    pub_type: 杂志文章


    authors: Hayes GR,Williams AM,Lucas JJ,Enns CA

    更新日期:1997-04-29 00:00:00

  • Specific interaction of wild-type and truncated mouse N-methylpurine-DNA glycosylase with ethenoadenine-containing DNA.

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    pub_type: 杂志文章


    authors: Roy R,Biswas T,Hazra TK,Roy G,Grabowski DT,Izumi T,Srinivasan G,Mitra S

    更新日期:1998-01-13 00:00:00

  • Identification of the catalytic residue of Thermococcus litoralis 4-alpha-glucanotransferase through mechanism-based labeling.

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    pub_type: 杂志文章


    authors: Imamura H,Fushinobu S,Jeon BS,Wakagi T,Matsuzawa H

    更新日期:2001-10-16 00:00:00

  • Energy dependent hydrogen ion accumulation in submitochondrial particles.

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    pub_type: 杂志文章


    authors: Rottenberg H,Lee CP

    更新日期:1975-06-17 00:00:00

  • Effects of pH and iminosugar pharmacological chaperones on lysosomal glycosidase structure and stability.

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    pub_type: 杂志文章


    authors: Lieberman RL,D'aquino JA,Ringe D,Petsko GA

    更新日期:2009-06-09 00:00:00

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    pub_type: 杂志文章


    authors: Gibbs CS,Zoller MJ

    更新日期:1991-06-04 00:00:00

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    pub_type: 杂志文章,评审


    authors: Li D,Liu C

    更新日期:2020-02-11 00:00:00

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    pub_type: 杂志文章


    authors: Dills WL Jr,Meyer WL

    更新日期:1976-10-05 00:00:00

  • Complementary DNA cloning and kinetic characterization of a novel intracellular serine proteinase inhibitor: mechanism of action with trypsin and factor Xa as model proteinases.

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    pub_type: 杂志文章


    authors: Morgenstern KA,Sprecher C,Holth L,Foster D,Grant FJ,Ching A,Kisiel W

    更新日期:1994-03-22 00:00:00

  • Beta-tubulin isotypes purified from bovine brain have different relative stabilities.

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    pub_type: 杂志文章


    authors: Schwarz PM,Liggins JR,Ludueña RF

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    pub_type: 杂志文章


    authors: Chang FY,Kawashima SA,Brady SF

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    pub_type: 杂志文章


    authors: Negash S,Huang S,Squier TC

    更新日期:1999-06-22 00:00:00

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    pub_type: 杂志文章


    authors: Pulliam DL,Sawyna V,Levine RJ

    更新日期:1983-05-10 00:00:00

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    authors: Zhu J,Lippa GM,Gulick AM,Tipton PA

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    pub_type: 杂志文章


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    pub_type: 杂志文章


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    pub_type: 杂志文章


    authors: Oliveira EB,Martins AR,Camargo AC

    更新日期:1976-05-04 00:00:00

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    pub_type: 杂志文章


    authors: Xu T,Zhou CZ,Xiao J,Liu J

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    pub_type: 杂志文章


    authors: Ho D,Merrill AR

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    pub_type: 杂志文章


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    pub_type: 杂志文章


    authors: Iakoucheva LM,Walker RK,van Houten B,Ackerman EJ

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    pub_type: 杂志文章


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    pub_type: 杂志文章


    authors: Brown KR,Keller GL,Pickering IJ,Harris HH,George GN,Winge DR

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    pub_type: 杂志文章


    authors: Sridevi K,Udgaonkar JB

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    pub_type: 杂志文章


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    pub_type: 杂志文章


    authors: Essodaigui M,Broxterman HJ,Garnier-Suillerot A

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    pub_type: 杂志文章


    authors: Ezratty A,Simon DI,Loscalzo J

    更新日期:1993-05-04 00:00:00