Biochemical and immunologic verification of <i>E. coli</i> Group 2 capsule inhibition through small molecules.

<p><b>A</b>) Orcinol reactivity of capsular material released by mild acid treatment of cultures grown with 1% DMSO vehicle (UTI89 and genetic capsule mutants) or 100 µM C7, DU001, DU003, DU005, DU007, DU008, or DU011. Data represent independent experiments performed in duplicate. Treatment of K1 strain UTI89 with compounds reduces amount of orcinol-reactive polysaccharides on surface of bacteria by ∼80%. <b>B</b>) Whole-cell anti-K1 dot blots of cultures of UTI89 or indicated genetic capsule mutants treated with 1% DMSO or 100 µM DU001, DU003, DU005, DU007, DU008, or DU011 indicate that treatment of cultures with compounds reduces K1 reactive material to levels comparable to those of genetic capsule mutants. ΔRI and ΔRII indicate a complete deletion of Region I of the capsule <i>kps</i> and Region II capsule <i>neu</i> loci, respectively.