FIG. 1.

Effect of the nanA mutation on the Neu5Ac lyase activity and colony morphotypes. Cultures of the wild type (WT) and the nanA mutant HG072 (nanA) were grown in modified M9 broth (A) or on a plate (B) containing 10 mM d-xylose, 10 mM l-proline, and 5 mM Neu5Ac. (A) Relative activities of Neu5Ac lyase were determined from samples removed at an A₆₀₀ of 0.5 as described in the text. Error bars represent the SEM. *, P ≤ 0.01; **, P ≤ 0.005. (B) Colony morphotypes of the strains after 24 h of growth. Complementation of the mutant with a functional nanA (pHG0704) is also presented as indicated.