Fig. 4.   Putative catabolism pathway of propanoate in the KEGG database. The blue and red lines are the possible catabolic pathway I and II, respectively.
Fig. 5.   The transition of different carbon atoms from propanol (or propanoate) in the two possible catabolic pathways. The blue hexagon denotes the coenzyme A groups. The colored circles denote carbon atoms of different position in the carbon backbone. The red, yellow and purple circles denote the carbon atoms from the first, second and third atom of the propanoate carbon backbone, respectively. Green atoms denote the carbon atoms from intracellular carbon dioxide.