Survival of enterococci and Tn916-like conjugative transposons in soil.

The persistence of Enterococcus faecalis, fecal enterococci from swine waste, and Tn916-like elements was determined following inoculation into autoclaved and native soil microcosms. When cells of E. faecalis CG110 (Tn916) were inoculated into native microcosms, enterococcal viability in the soil decreased approximately 5 orders of magnitude (4.

Identification of Mycobacterium paratuberculosis gene expression signals.

Mycobacterium paratuberculosis promoter-containing clones were isolated from a genomic DNA library constructed in the transcriptional-translational fusion vector pYUB76. The promoter-containing DNA fragments were identified in the surrogate host Mycobacterium smegmatis by expression of the promoterless lacZ reporter gene of pYUB76. The expression signals exhibited a wide range of strengths, as indicated by their corresponding beta-galactosidase activities.