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Compartmentalisation of metabolic activities in cells is crucial for enhancing and regulating energy and metabolism. While eukaryotes employ membrane-bound organelles, many bacteria generate protein-based and self-assembled metabolic organelles, called bacterial microcompartments (BMCs), to enhance or protect key metabolic pathways inside the cell. BMCs consist of a single-layer proteinaceous shell encapsulating internal enzymes and metabolites from the relative degradation pathway. BMCs play central roles in a range of biological processes, including CO2 fixation, pathogenesis, and microbial ecology, across diverse bacterial species. A typical example of a BMC is the 1,2-propanediol (1,2-PD) utilisation microcompartment (Pdu MCP) in Salmonella enterica serovar Typhimurium (S. Typhimurium) and other enteric bacteria, which participates in 1,2-PD degradation in enteric pathogenesis. We still have limited knowledge of the structure, composition, organisation, and self-assembly of Pdu MCPs. In this work, I seek a comprehensive understanding of the stoichiometric composition and organisation of Pdu MCPs in S. Typhimurium LT2. I obtain accurate stoichiometry of shell proteins and internal enzymes of the natural Pdu MCP by QconCAT-driven quantitative mass spectrometry. Genetic deletion of the major shell protein and absolute stoichiometry analysis reveal the stoichiometric and structural remodelling of metabolically functional Pdu MCPs. The obtained knowledge about the protein stoichiometry leads me to propose a model of the Pdu MCP structure. Moreover, I determine the role of individual shell proteins and unravel the biogenesis pathway of Pdu MCPs. I identify the proteins that bind the shell and cargo, and the gene product that distributes the Pdu MCP. I find the Pdu MCP undertakes a concomitant assembly process in which the shell and cargo assemble independently. In addition, I investigate the diffusion dynamics of Pdu MCPs. I find that Pdu MCPs are highly dynamic in S. Typhimurium LT2, but show a confined movement. The shell and enzymatic core of Pdu MCPs have distinctly different motions in which the enzyme core possesses a dynamic liquidlike nature. The findings in this thesis provide insights into the organisation and assembly principles of Pdu MCPs, and may inform strategies for repurposing natural microcompartments using synthetic biology for biotechnological applications.