The Refined Three-Dimensional Structure of Pectate Lyase C from Erwinia chrysanthemi at 2.2 Angstrom Resolution (Implications for an Enzymatic Mechanism).
The crystal structure of pectate lyase C (EC 4.2.2.2) from the enterobacterium Erwinia chrysanthemi (PelC) has been refined by molecular dynamics techniques to a resolution of 2.2 A to an R factor of 17.97%. The final model consists of 352 of the total 353 amino acids and 114 solvent molecules. The root-mean-square deviation from ideality is 0.009 A for bond lengths and 1.768[deg] for bond angles. The structure of PelC bound to the lanthanide ion lutetium, used as a calcium analog, has also been refined. Lutetium inhibits the enzymatic activity of the protein, and in the PelC-lutetium structure, the ion binds in the putative calcium-binding site. Five side-chain atoms form ligands to the lutetium ion. An analysis of the atomic-level model of the two protein structures reveals possible implications for the enzymatic mechanism of the enzyme.
Yoder
M. D.
MD
School of Biological Sciences, Division of Cell Biology and Biophysics, University of Missouri, Kansas City, Missouri 64110 (M.D.Y.).
Jurnak
F.
F