L-threonine kinase that catalyzes the conversion of L-threonine to L-threonine-O-3-phosphate. Involved in the de novo synthesis of adenosylcobalamin (coenzyme B12) and the assimilation of cobyric acid. 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 (Probable). This gene probably benefits from its induction via the Pdu promoter, rather than a physical interaction with the BMC (By similarity). ATP + L-threonine = ADP + H(+) + O-phospho-L-threonine Cofactor biosynthesis; adenosylcobalamin biosynthesis. Polyol metabolism; 1,2-propanediol degradation. Belongs to the GHMP kinase family. PduX subfamily.