Small-angle X-ray scattering studies of the oligomeric state and quaternary structure of the trifunctional proline utilization A (PutA) flavoprotein from Escherichia coli.

ABSTRACT: The trifunctional flavoprotein proline utilization A (PutA) links metabolism and gene regulation in Gram-negative bacteria by catalyzing the two-step oxidation of proline to glutamate and repressing transcription of the proline utilization regulon. Small-angle x-ray scattering (SAXS) and domain deletion analysis were used to obtain solution structural information for the 1320-residue PutA from Escherichia coli. Shape reconstructions show that PutA is a symmetric V-shaped dimer having dimensions of 205 × 85 × 55 Å. The particle consists of two large lobes connected by a 30-Å diameter cylinder. Domain deletion analysis shows that the N-terminal DNA-binding domain mediates dimerization. Rigid body modeling was performed using the crystal structure of the DNA-binding domain and a hybrid x-ray/

SUBMITTER: Singh RK 

PROVIDER: S-EPMC3234867 | biostudies-literature | 2011 Dec

REPOSITORIES: biostudies-literature