FIG 5.

EMSA analysis on CRP2 binding to the promoter sequence of nirK. (a) Multiple alignment and sequence logo analyses of promoter sequences upstream of nirK in S. loihica PV-4, S. denitrificans, S. amazonensis, Marinobacter psychrophilus, Marinobacter sp. BSs20148, Pseudomonas sp. CCOS 191, and Pseudomonas aeruginosa LESB58. The conserved motifs are highlighted. The consensus sequence is TTGA(N)₆TCAATT. (b) The binding of CRP2 with the nirK promoter sequence was observed in the presence of increasing levels of cyclic AMP. (c) Induced transcription of the plasmid-borne crp2 upregulated the expression of nirK in the in-frame deletion mutant Δcrp2, as revealed by reverse transcription-PCR (RT-PCR) (upper) and real-time PCR analyses (lower).