Localization and orientation of heavy-atom cluster compounds in protein crystals using molecular replacement.

ABSTRACT: Heavy-atom clusters (HA clusters) containing a large number of specifically arranged electron-dense scatterers are especially useful for experimental phase determination of large complex structures, weakly diffracting crystals or structures with large unit cells. Often, the determination of the exact orientation of the HA cluster and hence of the individual heavy-atom positions proves to be the critical step in successful phasing and subsequent structure solution. Here, it is demonstrated that molecular replacement (MR) with either anomalous or isomorphous differences is a useful strategy for the correct placement of HA cluster compounds. The polyoxometallate cluster hexasodium α-metatungstate (HMT) was applied in phasing the structure of death receptor 6. Even though the HA cluster is bou

SUBMITTER: Dahms SO 

PROVIDER: S-EPMC3565441 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature