Redesigned purification yields a fully functional PutA protein dimer from Escherichia coli.

Proline utilization by Escherichia coli and Salmonella typhimurium requires expression of genes putP (encoding a proline transporter) and putA. Genetic data indicate that the PutA protein is both put repressor and a respiratory chain-linked dehydrogenase. We report a redesigned purification procedure as well as the physical characteristics and biological activities of the PutA protein purified from E. coli. The purified protein was homogeneous …