Reverse Transcriptase PCR showing that bd1971, and control gene dnaK, are expressed throughout the predatory cycle of Bdellovibrio bacteriovorus. RNA was isolated at the time points indicated across the top of the gel during one round of synchronous Bdellovibrio infection of E. coli cells. Primers were designed to anneal specifically to the gene of interest. L = 100bp DNA ladder, AP = Attack Phase cells, 15-45 = 15-45 minutes respectively since infection, 1h-4h = hours respectively since infection. Ec = E. coli strain S17-1 RNA (negative control: no Bdellovibrio RNA); NT = control with no template RNA; gen = B. bacteriovorus HD100 genomic DNA (positive control). The cartoon above represents each stage in the predatory cycle. 