AUTHOR=Peng Qi , Wu Jianbo , Chen Xiaomin , Qiu Lili , Zhang Jie , Tian Hongtao , Song Fuping 

TITLE=Disruption of Two-component System LytSR Affects Forespore Engulfment in Bacillus thuringiensis

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=7

YEAR=2017

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2017.00468

DOI=10.3389/fcimb.2017.00468

ISSN=2235-2988

ABSTRACT=<p>Two-component regulatory systems (TCSs) play pivotal roles in bacteria sensing many different stimuli from environment. Here, we investigated the role of the LytSR TCS in spore formation in <italic>Bacillus thuringiensis</italic> (<italic>Bt</italic>) subsp. <italic>kurstaki</italic> HD73. <italic>lacZ</italic> gene fusions revealed that the transcription of the downstream genes, <italic>lrgAB</italic>, encoding two putative membrane-associated proteins, is regulated by LytSR. The sporulation efficiency of a <italic>lytSR</italic> mutant was significantly lower than that of wild-type HD73. A confocal microscopic analysis demonstrated that LytSR modulates the process of forespore engulfment. Moreover, the transcription of the <italic>lytSR</italic> operon is regulated by the mother-cell transcription factor SigE, whereas the transcription of the sporulation gene <italic>spoIIP</italic> was reduced in the <italic>lytSR</italic> mutant, as demonstrated with a β-galactosidase activity assay. These results suggest that LytSR modulates forespore engulfment by affecting the transcription of the <italic>spoIIP</italic> gene in <italic>Bt</italic>.</p>