The periodontopathogen Aggregatibacter actinomycetemcomitans synthesizes several virulence factors, including cytolethal distending toxin (CDT). We identified an A. actinomycetemcomitans strain isolated from two patients with advance chronic periodontitis that has a regular cdtABC operon, which, however, codes for a unique, shorter, variant of the CdtB subunit.
COBISS.SI-ID: 3944783
We demonstrated that a large AsnC nucleosome-like structure, in conjunction with two LexA molecules, prevent cea8 transcription initiation and that AsnC binding activity is directly modulated by L asparagine. We show that L-asparagine is an environmental factor that has a marked impact on cea8 promoter regulation. Our results show that AsnC also modulates the expression of several other DNase and RNase colicin genes but does not substantially affect pore-forming colicin K gene expression. We propose that selection pressure has “chosen” highly conserved regulators to control colicin expression in E. coli strains, enabling similar colicin gene silencing among bacteria upon exchange of colicinogenic plasmids.
COBISS.SI-ID: 3511887
Protein Usp is a virulence factor that induces genome damage/fragmentation, rearrangement of the cytoskeleton as well as apoptosis of cells of human cell lines. Due to its genotoxic activity, usp could involved in chronic inflammatory disease of the gastrointestinal tract and in cancer.
COBISS.SI-ID: 2871119
All species require DNA repair pathways to maintain the integrity of their genomes. However, the bacterial SOS response has a broader role as it also regulates virulence.
COBISS.SI-ID: 2968911
The population of Halobacterium walsbyi was in the studied saltern brine composed of numerous clonal lineages that differd in surface structures including the cell wall. This type of variation probably reflects a number of mechanisms that minimize the infection rate of predating viruses.
COBISS.SI-ID: 3556687