I am trying to obtain the pathway information for synthesis of Lignin,GAX and Cellulose in Sorghum. I am quite new to biology and genetics (EE background). I would appreciate it if y'all can provide me with some websites or books where such info maybe available. I have already looked in KEGG. Thank you very much.
The other big metabolic database site besides Kegg is MetaCyc which certainly responds to searches for lignin and cellulose.
The problem with lignin is that it is a very complex molecule, so in both Kegg and MetaCyc there are a many reactions involved in its synthesis. Cellulose is less complex and I have no idea what GAX is, despite an internet search. If you are so new to biochemical reactions and metabolic pathways that you cannot handle the results of a MetaCyc search on lignin you should easily be able to find articles devoted specifically to cellulose and lignin, perhaps using Wikipedia as a start.