Crystal structure of the CN-hydrolase SA0302 from the pathogenic bacteriumStaphylococcus aureusbelonging to the Nit and NitFhit Branch of the nitrilase superfamily

Cyanide bioremediation: the potential of engineered nitrilases

The cyanide-degrading nitrilases are of notable interest for their potential to remediate cyanide contaminated waste streams, especially as generated in the gold mining, pharmaceutical, and electroplating industries. This review provides a brief overview of cyanide remediation in general but with a particular focus on the cyanide-degrading nitrilases. These are of special interest as the hydrolysis reaction does not require secondary substrates or cofactors, making these enzymes particularly good candidates for industrial remediation processes. The genetic approaches that have been used to date for engineering improved enzymes are described; however, recent structural insights provide a promising new approach.

The structure of SAV1646 from Staphylococcus aureus belonging to a new `ribosome-associated' subfamily of bacterial proteins

The crystal structure of the SAV1646 protein from the pathogenic microorganism Staphylococcus aureus has been determined at 1.7 Å resolution. The 106-amino-acid protein forms a two-layer sandwich with α/β topology. The protein molecules associate as dimers in the crystal and in solution, with the monomers related by a pseudo-twofold rotation axis. A sequence-homology search identified the protein as a member of a new subfamily of yet uncharacterized bacterial `ribosome-associated' proteins with at least 13 members to date. A detailed analysis of the crystal protein structure along with the genomic structure of the operon containing the sav1646 gene allowed a tentative functional model of this protein to be proposed. The SAV1646 dimer is assumed to form a complex with ribosomal proteins L21 and L27 which could help to complete the assembly of the large subunit of the ribosome.