Determination of d-alanine concentration needed to support growth of the Δ<i>bpsl2179/</i>Δ<i>bpss0711</i> alanine racemase deficient mutant of <i>B. pseudomallei</i> K96243 on LB agar medium.

<p>Overnight cultures of the wild type, Δ<i>bpsl2179/</i>Δ<i>bpss0711</i> mutant, and Δ<i>bpsl2179/</i>Δ<i>bpss0711</i> mutant complemented with pALR-comp were inoculated into LB broth containing 10 mM d-alanine. Cultures were grown to an OD_{600 nm} = 0.2 and plated onto LB agar without d-alanine (0 mM) or with d-alanine at concentrations from 1.25 mM to 10 mM as indicated. Panel A: <i>B. pseudomallei</i> K96243. Panel B: The Δ<i>bpsl2179/</i>Δ<i>bpss0711</i> mutant of <i>B. pseudomallei</i> K96243. Panel C.: The Δ<i>bpsl2179/</i>Δ<i>bpss0711</i> mutant of <i>B. pseudomallei</i> K96243 complemented with plasmid pAlr-comp. Comparable results were obtained with isogenic wild type, alanine racemase deficient, and complemented alanine racemase deficient strains of <i>B. pseudomallei</i> 1026b and <i>B. mallei</i> ATCC 23344 (data not shown).