Publications

• Structure of E. coli ketopantoate hydroxymethyl transferase complexed with ketopantoate and Mg2+, solved by locating 160 selenomethionine sites.

  von Delft F., Inoue T., Saldanha S.A., Ottenhof H.H., Schmitzberger F., Birch L.M., Dhanaraj V., Witty M., Smith A.G., Blundell T.L., Abell C.

  We report the crystal structure of E. coli ketopantoate hydroxymethyltransferase (KPHMT) at 1.9 A resolution, in complex with its product, ketopantoate. KPHMT catalyzes the first step in the biosynthesis of pantothenate (vitamin B(5)), the precursor of coenzyme A and the acyl carrier protein cofac ... >> More

  We report the crystal structure of E. coli ketopantoate hydroxymethyltransferase (KPHMT) at 1.9 A resolution, in complex with its product, ketopantoate. KPHMT catalyzes the first step in the biosynthesis of pantothenate (vitamin B(5)), the precursor of coenzyme A and the acyl carrier protein cofactor. The structure of the decameric enzyme was solved by multiwavelength anomalous dispersion to locate 160 selenomethionine sites and phase 560 kDa of protein, making it the largest structure solved by this approach. KPHMT adopts the (betaalpha)(8) barrel fold and is a member of the phosphoenolpyruvate/pyruvate superfamily. The active site contains a ketopantoate bidentately coordinated to Mg(2+). Similar binding is likely for the substrate, alpha-ketoisovalerate, orienting the C3 for deprotonation. << Less

  Structure 11:985-996(2003) [PubMed] [EuropePMC]

• Cloning and sequencing of the Escherichia coli panB gene, which encodes ketopantoate hydroxymethyltransferase, and overexpression of the enzyme.

  Jones C.E., Brook J.M., Buck D., Abell C., Smith A.G.

  The panB gene from Escherichia coli, encoding the first enzyme of the pantothenate biosynthesis pathway, ketopantoate hydroxymethyltransferase (KPHMT), has been isolated by functional complementation of a panB mutant strain with an E. coli genomic library. The gene is 792 bp long, encoding a prote ... >> More

  The panB gene from Escherichia coli, encoding the first enzyme of the pantothenate biosynthesis pathway, ketopantoate hydroxymethyltransferase (KPHMT), has been isolated by functional complementation of a panB mutant strain with an E. coli genomic library. The gene is 792 bp long, encoding a protein of 264 amino acids with a predicted M(r) of 28,179. The identity of the gene product as ketopantoate hydroxymethyltransferase was confirmed by purification of the enzyme protein, which was overexpressed approximately 50-fold in the mutant harboring the gene on a high-copy-number plasmid. The N-terminal amino acid sequence of the purified protein was found to be identical to that predicted from the gene sequence, as was its mass, determined by electrospray mass spectrometry. Upstream of the panB gene is an incomplete open reading frame encoding a protein of 220 amino acids, which shares sequence similarity to fimbrial precursor proteins from other bacteria. Northern (RNA) analysis showed that the panB gene is likely to be cotranscribed with at least one other gene but that this is not the putative fimbrial protein, since no transcripts for this gene could be detected. << Less

  J. Bacteriol. 175:2125-2130(1993) [PubMed] [EuropePMC]

• Comparative analysis of the Escherichia coli ketopantoate hydroxymethyltransferase crystal structure confirms that it is a member of the (betaalpha)8 phosphoenolpyruvate/pyruvate superfamily.

  Schmitzberger F., Smith A.G., Abell C., Blundell T.L.

  Escherichia coli ketopantoate hydroxymethyltransferase (KPHMT) catalyzes the first step in the biosynthesis pathway of pantothenate (vitamin B(5)), the transfer of a hydroxymethyl group onto alpha-ketoisovalerate. Here we describe a detailed comparative analysis of the KPHMT crystal structure and ... >> More

  Escherichia coli ketopantoate hydroxymethyltransferase (KPHMT) catalyzes the first step in the biosynthesis pathway of pantothenate (vitamin B(5)), the transfer of a hydroxymethyl group onto alpha-ketoisovalerate. Here we describe a detailed comparative analysis of the KPHMT crystal structure and the identification of structural homologues, some of which have remarkable similarities in their active sites, modes of binding to substrates, and mechanisms. We show that KPHMT forms a family within the phosphoenolpyruvate/pyruvate superfamily. Based on the analysis, we propose that in this superfamily there should be a subdivision into two groups. This paper completes our structural analysis of the E. coli enzymes in the pantothenate pathway. << Less

  J Bacteriol 185:4163-4171(2003) [PubMed] [EuropePMC]