I have a gene list with different expression values, I would like to know if there is any method based on a gene list that I can trace the affected metabolic pathways.
If you are starting with just genes, then you should perform a standard gene enrichment analysis; however, only enrich the genes for KEGG pathways. Then, using the Pathway Analysis feature of MetaboAnalyst, you can input your statistically significantly enriched KEGG pathway IDs in order to further enrich metabolic pathways.
You should also explore the other functions of MetaboAnalyst - it is very popular in the World of metabolomics.
I really liked the MetaboAnalyst, I found a tab to put gene list with optional fold changes, it's very interesting.
How to do protein pathway analysis rna-seq?
How To Compare Metabolic Pathways?
To compare gene expression profiles.