A Screen Reveals Bexarotene, Sorafenib and Certain of its Analogues as Common and Effective Inhibitors of Growth of Bacteria that Grow on LB but not on McConkey Agar.

Abstract

A screen of 61 compounds identified bexarotene and sorafenib as inhibitors of bacterial isolates that grew on LB agar but not on McConkey agar. The effect of bexarotene was durable, whereas sorafenib simply retarded growth. Two sorafenib analogues, previously not described, dubbed JSR-A40 and JSR-N42, displayed durable effects. Upon extending this to a larger group of bacteria from different sources it was found that both bexarotene and JSR-N42 were active in concentrations from between 1.25-10 {micro}M in 42 of bacteria growing in LB but not McConkey medium, whereas bacteria growing on McConkey agar were all found to be insensitive at that concentration. Both bexarotene and N42 displayed rather broad characteristics similar to clindamycin, however non-overlapping. Sensitivity to clindamycin, if observed, was generally higher. It was found that the urea type compound N42 at 5 {micro}M was broader active than clindamycin at 5 {micro}M in this set of isolates.