mycobacterium tuberculosis causing infection of an implantable biventricular defibrillator mycobacterial infection of implantable cardiac devices is rare and infection of pacing system components with m tuberculosis has been reported on only three previous occasions involving epicardial pacing systems in two cases we report here a pocket infection with m tuberculosis in a transvenous biventricular defibrillator cyclic amp directly activates nasp an nacyl amino acid antibiotic biosynthetic enzyme cloned from an uncultured betaproteobacterium the cyclic amp campdependent biosynthesis of nacylphenylalanine antibiotics by nasp an environmental dnaderived nacyl amino acid synthase is controlled by an naspassociated cyclic nucleotidebinding domain and is independent of the global camp signal transducer camp receptor protein a 16s rrna gene sequence found on the same environmental dna cosmid as nasp is most closely related to 16s sequences from betaproteobacteria