Transcription regulation by CavA cyclase in Acinetobacter baumannii AB5075
We perform RNA-seq for comparison of deleted cavA wiht empty vector and complemented strains in A. baumannii AB5075 in order to assess the transcription regulation uder the control of this cyclase. A. baumannii AB5075 ?cavA EV and ?cavA+cavA cultures were grown in LB medium with 1mM IPTG (3 biological replicates per strain) until reaching mid-exponential phase. At this point, cells were harvested, treated with RNAlate for preservation of total RNA and stored at -80 C. After that, total RNA was extracted from each sample. The results showed 234 differentially expressed genes of which 143 were upregulated and 91 were downregulated in the ?cavA+cavA complemented strain compared to the deleted cavA mutant harbouring empty vector (?cavA EV). The gene functional groups showing the strongest transcriptional alterations were those related to twitching motility (upregulation of genes involves in biogenesis and control of Type IV pili and com genes) as well as biofilm formation, exopolysaccharides production and fimbriae biogenesis (downregulation of csu operon, pga operon and ABUW_2052-2055). Also, genes related to inter- and intracellular signalling were differentially expressed. Cyclic AMP response regulator vfr and genes involved in c-di-GMP synthesis (ABUW_2135) and degradation (ABUW_1138) were upregulated while another gene linked to c-di-GMP degradation (ABUW_2631) and autoinducer synthase encoding gene abaI (part of the quorum sensing signalling system) were downregulated. Overall design: Three independent replicates of A. baumannii AB5075 ?cavA EV and ?cavA+cavA cultures were grown in LB medium with 1mM IPTG (3 biological replicates per strain) until reaching mid-exponential phase. At this point, cells were harvested, treated with RNAlate for preservation of total RNA and stored at -80°C. After that, total RNA was extracted from each sample.