1s5o
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Structural and Mutational Characterization of L-carnitine Binding to Human carnitine Acetyltransferase
OverviewOverview
We report the crystal structure of a binary complex of human peroxisomal carnitine acetyltransferase and the substrate l-carnitine, refined to a resolution of 1.8 Angstrom with an R(factor) value of 18.9% (R(free)=22.3%). L-carnitine binds to a preformed pocket in the active site tunnel of carnitine acetyltransferase aligned with His(322). The quaternary nitrogen of carnitine forms a pi-cation interaction with Phe(545), while Arg(497) forms an electrostatic interaction with the negatively charged carboxylate group. An extensive hydrogen bond network also occurs between the carboxylate group and Tyr(431), Thr(444), and a bound water molecule. Site-directed mutagenesis and kinetic characterization reveals that Tyr(431), Thr(444), Arg(497), and Phe(545) are essential for high affinity binding of L-carnitine.
DiseaseDisease
Known disease associated with this structure: Carnitine acetyltransferase deficiency (1) OMIM:[600184]
About this StructureAbout this Structure
1S5O is a Single protein structure of sequence from Homo sapiens with as ligand. Active as Carnitine O-acetyltransferase, with EC number 2.3.1.7 Full crystallographic information is available from OCA.
ReferenceReference
Structural and mutational characterization of L-carnitine binding to human carnitine acetyltransferase., Govindasamy L, Kukar T, Lian W, Pedersen B, Gu Y, Agbandje-McKenna M, Jin S, McKenna R, Wu D, J Struct Biol. 2004 Jun;146(3):416-24. PMID:15099582
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