NMR Assignment of 2H, 13C and 15N Labeled Amino-Terminal Domain of Apo-Pantothenate Synthetase from E. coli

Abstract

Pantothenate (vitamin $b_5$) is an essential precursor for the biosynthesis of coenzyme A (CoA), an essential metabolite for many important cellular processes (Brown et al., 1987). Pantothenate Synthetase (PS) catalyzes the ATP dependent condensation of D-pantoate with $_\beta$-alanine to give rise to pantothenate. Our interest lies in studying the solution-state inter-domain interactions in E. coli PS that results in formation of the catalytic site. As a first step we have cloned and over-expressed an isotopically enriched sample of the dimeric amino-terminal domain (residues 1–176) of E. coli PS. Here we report the backbone and side-chain assignments for HN, $^{13}C (C^a, C^\beta & CO)$ and $^{15}N$ nuclei of the protein, obtained using triple resonance NMR experiments (Yamazaki et al., 1994). CSI and NOE data indicates that the protein is well folded containing both \alpha-helices and $_\beta$-sheet. Assignment for \sim 95% of backbone and side-chain resonances for the catalytic domain has been obtained and deposited in BMRB (accession # 6940).