1m33
Crystal Structure of BioH at 1.7 ACrystal Structure of BioH at 1.7 A
Structural highlights
FunctionBIOH_ECOLI The physiological role of BioH is to remove the methyl group introduced by BioC when the pimeloyl moiety is complete. It allows to synthesize pimeloyl-ACP via the fatty acid synthetic pathway through the hydrolysis of the ester bonds of pimeloyl-ACP esters. E.coli employs a methylation and demethylation strategy to allow elongation of a temporarily disguised malonate moiety to a pimelate moiety by the fatty acid synthetic enzymes. BioH shows a preference for short chain fatty acid esters (acyl chain length of up to 6 carbons) and short chain p-nitrophenyl esters. Also displays a weak thioesterase activity. Can form a complex with CoA, and may be involved in the condensation of CoA and pimelic acid into pimeloyl-CoA, a precursor in biotin biosynthesis.[1] [2] [3] [4] Catalyzes the hydrolysis of the methyl ester bond of dimethylbutyryl-S-methyl mercaptopropionate (DMB-S-MMP) to yield dimethylbutyryl mercaptopropionic acid (DMBS-MPA) during the biocatalytic conversion of simvastin acid from monacolin J acid. Can also use acyl carriers such as dimethylbutyryl-S-ethyl mercaptopropionate (DMB-S-EMP) and dimethylbutyryl-S-methyl thioglycolate (DMB-S-MTG) as the thioester substrates.[5] [6] [7] [8] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedStructural proteomics projects are generating three-dimensional structures of novel, uncharacterized proteins at an increasing rate. However, structure alone is often insufficient to deduce the specific biochemical function of a protein. Here we determined the function for a protein using a strategy that integrates structural and bioinformatics data with parallel experimental screening for enzymatic activity. BioH is involved in biotin biosynthesis in Escherichia coli and had no previously known biochemical function. The crystal structure of BioH was determined at 1.7 A resolution. An automated procedure was used to compare the structure of BioH with structural templates from a variety of different enzyme active sites. This screen identified a catalytic triad (Ser82, His235, and Asp207) with a configuration similar to that of the catalytic triad of hydrolases. Analysis of BioH with a panel of hydrolase assays revealed a carboxylesterase activity with a preference for short acyl chain substrates. The combined use of structural bioinformatics with experimental screens for detecting enzyme activity could greatly enhance the rate at which function is determined from structure. Integrating structure, bioinformatics, and enzymology to discover function: BioH, a new carboxylesterase from Escherichia coli.,Sanishvili R, Yakunin AF, Laskowski RA, Skarina T, Evdokimova E, Doherty-Kirby A, Lajoie GA, Thornton JM, Arrowsmith CH, Savchenko A, Joachimiak A, Edwards AM J Biol Chem. 2003 Jul 11;278(28):26039-45. Epub 2003 May 5. PMID:12732651[9] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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