89157-28-8 Cholera toxin, B subunit (50-64) Ctp3 peptide L-Alanine, L-valyl-L-alpha-glutamyl-L-valyl-L-prolylglycyl-L-seryl-L-glutaminyl-L-histidyl-L-isoleucyl-L-alpha-aspartyl-L-seryl-L-glutaminyl-L-lysyl-L-lysyl-