1. NCBI: Basic Local Alignment Search Tool, http://blast.ncbi.nlm.nih.gov/Blast.cgi
2. Invitrogen Corporation: Vector NTI Software, http://www.invitrogen.com/site/us/en/home/Applications/Cloning/Vector-Design-Software.html
3. National Institute of General Medical Sciences: MetaCyc Encyclopedia of Metabolic Pathways, http://www.metacyc.org/
4. University of Minnesota: University of Minnesota Biocatalysis/Biodegradation Database, http://umbbd.msi.umn.edu/
5. Kanehisa Laboratories: KEGG Pathways Database, http://www.genome.ad.jp/kegg/pathway.html