Plays an essential role in assembly and/or stability of the bacterial microcompartment (BMC) dedicated to 1,2-propanediol (1,2-PD) degradation. Overexpression impairs BMC formation. 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. Polyol metabolism; 1,2-propanediol degradation. Interacts with shell protein PduK. BMC production is induced by growth on 1,2-PD vitamin B12 medium. Impaired for BMC assembly, with a disrupted, unstable BMC shell. Bacterial microcompartments (BMC) 100-200 nm in cross section are formed during aerobic growth on minimal 1,2-PD-B12 or anaerobic growth on 1,2-PD-tetrathionate medium, but not during aerobic growth on glucose, anerobic growth on glucose or pyruvate-tetrathionate (PubMed:10498708). BMCs can constitute up to 10% of total cell protein (PubMed:12923081). Belongs to the PduM family.