Fig 3.
Complementation of argJ in strain DGI2, which requires arginine, hypoxanthine, and uracil for growth. DGI2 was transformed with pMR90 to generate strain MR574, which expresses the wild-type argJ under the control of Ptet at the iga-trpB locus. Strain MR574 was grown in liquid gonococcal genetic medium (GGM) containing arginine or in medium without added arginine. ArgJ production was induced during growth in GGM lacking arginine by the addition of 0.2 ng/ml or 2 ng/ml ATc. The mean ± standard deviation of three independent experiments is shown. *, growth of MR574 in the presence of ATc inducer was not significantly different from growth in the presence of arginine (Student's two-tailed t test, P > 0.05), but growth under both conditions was significantly different from growth in the absence of both arginine and ATc (Student's two-tailed t test, P < 0.05).