AUTHOR=Cao Zhang-lei , Tan Tong-tong , Zhang Yan-li , Han Lu , Hou Xiao-yue , Ma Hui-yong , Cai Jun 

TITLE=NagRBt Is a Pleiotropic and Dual Transcriptional Regulator in Bacillus thuringiensis

JOURNAL=Frontiers in Microbiology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2018.01899

DOI=10.3389/fmicb.2018.01899

ISSN=1664-302X

ABSTRACT=<p>NagR, belonging to the GntR/HutC family, is a negative regulator that directly represses the <italic>nagP</italic> and <italic>nagAB</italic> genes, which are involved in GlcNAc transport and utilization in <italic>Bacillus subtilis</italic>. Our previous work confirmed that the chitinase B gene (<italic>chiB</italic>) of <italic>Bacillus thuringiensis</italic> strain Bti75 is also negatively controlled by YvoA<sub>Bt</sub>, the ortholog of NagR from <italic>B. subtilis</italic>. In this work, we investigated its regulatory network in Bti75 and found that YvoA<sub>Bt</sub> is an N-acetylglucosamine utilization regulator primarily involved in GlcNAc catabolism; therefore YvoA<sub>Bt</sub> is renamed as NagR<sub>Bt</sub>. The RNA-seq data revealed that 27 genes were upregulated and 14 genes were downregulated in the Δ<italic>nagR</italic> mutant compared with the wild-type strain. The regulon (exponential phase) was characterized by RNA-seq, bioinformatics software, electrophoretic mobility shift assays, and quantitative real-time reverse transcription PCR. In the Bti75 genome, 19 genes that were directly regulated and 30 genes that were indirectly regulated by NagR<sub>Bt</sub> were identified. We compiled <italic>in silico, in vitro</italic>, and <italic>in vivo</italic> evidence that NagR<sub>Bt</sub> behaves as a repressor and activator to directly or indirectly influence major biological processes involved in amino sugar metabolism, nucleotide metabolism, fatty acid metabolism, phosphotransferase system, and the Embden–Meyerhof–Parnas pathway.</p>