Escherichia coli, wanda aka fi sani da E. coli, wani nau'in kwayoyin cuta ne na gram-negative, mai siffar sanda da aka fi samu a cikin ƙananan hanji na kwayoyin jini mai dumi. Yayin da yawancin nau'ikan E. coli ba su da lahani kuma suna taka muhimmiyar rawa wajen kiyaye lafiyar hanji, wasu nau'ikan na iya haifar da rashin lafiya, ciki har da cututtukan da ke haifar da abinci, cututtukan urinary, da kuma wasu lokuta mafi muni irin su sepsis. Ana amfani da E. coli a matsayin abin koyi a cikin ilmin halitta na kwayoyin halitta da binciken kwayoyin halitta saboda saurin girma da sauƙi na al'ada a cikin dakin gwaje-gwaje.