FIG 5.

Expression (A) and activity (B) of the thermonuclease NucI is unchanged. (A) nucI gene expression was measured during the mid-logarithmic (3 h) and stationary (6 h) phases of growth or in 24-h-grown biofilms. The mRNA levels were quantified by real-time PCR and normalized against the relative quantities of the aroE and gyrB housekeeping gene transcripts. The data were analyzed with one-way ANOVA and a Bonferroni's posttest. (B) NucI activity, observed as clearing zones around bacterial growth on DNase agar, was similar among wild-type w701(pRB473) (2), Mut12(pRB473) (1), and the complemented mutants Mut12(pRBcomEB) (3) and Mut12(pRBcomEB/EC) (4). S. aureus SA113(pCU1) (6) and S. epidermidis O-47(pCU1) (5) served as positive and negative controls, respectively.