ABCG2 and infection: KEGG enrichment analysis also revealed that several pathways were specifically affected at the later stage of infection; these included secondary metabolic pathways such as “tropane, piperidine and pyridine alkaloid biosynthesis,” “steroid biosynthesis,” “ABC transporters,” “biotin metabolism,” “sphingolipid metabolism,” “glycosaminoglycan metabolism,” “folate biosynthesis,” “alpha-linolenic acid metabolism,” “regulation of autophagy,” “ubiquinone and other terpenoid-quinone biosyntheses,” and some “amino acid metabolism” pathways.