Characterization of the PduS cobalamin reductase of Salmonella enterica and its role in the Pdu microcompartment.

ABSTRACT: Salmonella enterica degrades 1,2-propanediol (1,2-PD) in a coenzyme B12 (adenosylcobalamin, AdoCbl)-dependent fashion. Salmonella obtains AdoCbl by assimilation of complex precursors, such as vitamin B12 and hydroxocobalamin. Assimilation of these compounds requires reduction of their central cobalt atom from Co3+ to Co2+ to Co+, followed by adenosylation to AdoCbl. In this work, the His6-tagged PduS cobalamin reductase from S. enterica was produced at high levels in Escherichia coli, purified, and characterized. The anaerobically purified enzyme reduced cob(III)alamin to cob(II)alamin at a rate of 42.3±3.2 μmol min(-1) mg(-1), and it reduced cob(II)alamin to cob(I)alamin at a rate of 54.5±4.2 nmol min(-1) mg(-1) protein. The apparent Km values of PduS-His6 were 10.1±0.7 μM for NADH and 67

SUBMITTER: Cheng S 

PROVIDER: S-EPMC2944522 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature