FIG. 2.

Without surface disinfection, GFP-expressing M. marinum were observed on the embryo chorion (A) after 24 h and in the larval zebrafish gut (arrowhead in C) after 6 days. GFP-expressing mycobacteria were present on the chorion (B) after 24 h, but absent in the larval zebrafish gut (D) after 6 days when the chorion was surface disinfected using 30 ppm sodium hypochlorite for 10 min. Larvae are positioned anterior to the left, dorsal up. GFP, green fluorescent protein. Color images available online at www.liebertpub.com/zeb