Converts cob(I)alamin to adenosylcobalamin (adenosylcob(III)alamin), the cofactor for propanediol dehydratase. Found in the bacterial microcompartment (BMC) dedicated to 1,2-propanediol (1,2-PD) degradation. PduS and PduO allow regeneration of the adenosylcobalamin cofactor within the BMC. Expression of a cosmid containing the full 21-gene pdu operon in E.coli allows E.coli to grow on 1,2-propanediol (1,2-PD) with the appearance of bacterial microcompartments (BMC) in its cytoplasm. The 1,2-PD-specific bacterial microcompartment (BMC) concentrates low levels of 1,2-PD catabolic enzymes, concentrates volatile reaction intermediates thus enhancing pathway flux and keeps the level of toxic, mutagenic propionaldehyde low. ATP + cob(I)alamin-[corrinoid adenosyltransferase] = adenosylcob(III)alamin + apo-[corrinoid adenosyltransferase] + triphosphate Polyol metabolism; 1,2-propanediol degradation. Cofactor biosynthesis; adenosylcobalamin biosynthesis. Forms a complex with PduS. Belongs to the Cob(I)alamin adenosyltransferase family. PduO subfamily.