Bacterial glycerol uptake and catabolism through glycerol 3-phosphate

A reusable bacterial module for channel-mediated glycerol uptake followed by conversion to dihydroxyacetone phosphate. GlpF facilitates glycerol movement across the cytoplasmic membrane, GlpK traps intracellular glycerol as sn-glycerol 3-phosphate, and FAD-dependent GlpD oxidizes that intermediate to dihydroxyacetone phosphate while reducing the respiratory quinone pool.

The module starts with extracellular glycerol and ends with dihydroxyacetone phosphate plus reduced quinone. Passive channel transport does not itself consume ATP; phosphorylation by GlpK provides metabolic trapping. Alternative active glycerol transporters, glycerol dehydrogenase routes, phospholipid-derived glycerol 3-phosphate, quinol reoxidation, and downstream glycolysis are outside the boundary. PSEPK-specific transcription and regulation at the glp locus are supporting context, not required parts.