Differential expression of glycerol catabolism genes. Designations: glpF, glycerol permease; glpK, glycerol kinase; glpO, alpha-glycerophosphate oxidase; gpsA, glycerol-3-phosphate dehydrogenase; dhaMLK, PTS-dependent dihydroxyacetone kinase; yloV, putative dihydroxyacetone kinase. Abbreviations: DHA, dihydroxyacetone; out, outside the cell; in, inside the cell. The direction of the arrows adjacent to the enzyme names indicates up- or downregulation.