Structure and mechanism of the bifunctional CinA enzyme from Thermus thermophilus.

ABSTRACT: CinA is a widely distributed protein in Gram-positive and Gram-negative bacteria. It is associated with natural competence and is proposed to have a function as an enzyme participating in the pyridine nucleotide cycle, which recycles products formed by non-redox uses of NAD. Here we report the determination of the crystal structure of CinA from Thermus thermophilus, in complex with several ligands. CinA was shown to have both nicotinamide mononucleotide deamidase and ADP-ribose pyrophosphatase activities. The crystal structure shows an unusual asymmetric dimer, with three domains for each chain; the C-terminal domain harbors the nicotinamide mononucleotide deamidase activity, and the structure of a complex with the product nicotinate mononucleotide suggests a mechanism for deamidation. The

SUBMITTER: Karuppiah V 

PROVIDER: S-EPMC4246079 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature