Title : Refined structures of placental alkaline
phosphatase show a consistent pattern of interactions at the peripheral
site
Abstract :
- In order to gain deeper insights into the functional sites of human placental alkaline phosphatase , the structures of the enzyme with the putative regulators L- Phe , pNPP and 5'-AMP [Llinas et al. (2005), J. Mol
- Biol
- 350, 441-451] were re-refined
- Significant variations in ligand position ing and identity were found compared with the previous report
- The multiple corrections to the model improved the phases and the electron-density maps, allowing the modeling of omitted side chains and multiple disordered residues
- These improvements led to a change in the position of L- Phe at the peripheral binding site , which appeared to be reversed
- The structure with pNPP contained only p-nitrophenol in three distinct sites , while the structure with 5'-AMP contained the p-nitrophenyl group in two of the sites instead of 5'-AMP
- Comparison of the re-refined models shows a consistent pattern of interactions at the peripheral site