Sequence-specific 1H-NMR assignments and secondary structure of the lipoyl domain of the Bacillus stearothermophilus pyruvate dehydrogenase multienzyme complex.
The lipoyl domain (residues 1-85) of the lipoate-acetyltransferase polypeptide chain of the pyruvate dehydrogenase multienzyme complex of Bacillus stearothermophilus has been subjected to detailed structural analysis by means of two-dimensional (2D) 1H-NMR spectroscopy at 400 MHz. Sequence-specific proton resonance assignments were made, but at this field strength not all of the side-chain protons could be assigned, especially from complex spin systems like those of leucine, proline and lysine residues. Measurement of short-range interproton distances identified two extensive regions of beta-sheet, each containing four anti-parallel peptide strands. The lipoyl-lysine residue (Lys42) is located in a tight turn at a corner of one sheet, the N-terminal and C-terminal residues of the domain are close together in two adjacent beta-strands in the other. The lipoylated and unlipoylated forms of the domain have almost identical spectra, indicating that there is little, if any, conformational change in the protein as a result of the post-translational modification.
Cambridge Centre for Molecular Recognition, Department of Biochemistry, University of Cambridge, England.
F
F
Dardel
E D
ED
Laue
R N
RN
Perham
D000123:Acetyltransferases / Q000737:chemistry*; D000595:Amino Acid Sequence; D051047:Dihydrolipoyllysine-Residue Acetyltransferase; D001411:Geobacillus stearothermophilus / Q000201:enzymology*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D011487:Protein Conformation; D011768:Pyruvate Dehydrogenase Complex / Q000737:chemistry*
D011768:Pyruvate Dehydrogenase Complex; D000123:Acetyltransferases; D051047:Dihydrolipoyllysine-Residue Acetyltransferase