The relationships among growth in the presence of bile, deconjugation of sodium taurocholate, and assimilation of cholesterol by 19 cultures of Lactobacillus acidophilus were examined. Cultures of L. acidophilus were grown at 37-degrees-C in lactobacilli MRS broth supplemented with sodium thioglycollate, sodium taurocholate, and cholesterol (cholesterol phosphatidyl choline micelles). Deconjugation activity was maximum in the late exponential phase of growth, which also coincided with maximum assimilation of cholesterol. Considerable variation existed among cultures in their ability to grow in the presence of bile, to deconjugate sodium taurocholate, and to assimilate cholesterol. However, statistical analyses revealed no significant correlations.