Communication between mother cell and isolated forespore involves a specialised connection system that allows nurturing of the forespore and continued macromolecular synthesis, required to finalise spore maturation. Here,
we review current understanding of this feeding channel formed by a forespore protein, SpoIIQ, and a mother cell protein, SpoIIIAH, in the GSK3 inhibitor model organism Bacillus subtilis and the important human pathogen Clostridium difficile. We also analyse the presence of this channel across endospore-forming bacteria and highlight the main questions still remaining. “
“Streptococcus suis 2 (SS2) is a zoonotic pathogen that can participate in biofilm formation to survive in hostile environments. In this study, virulent SS2 strains HA9801 and ZY05719 displayed increased biofilm formation compared with SS2 avirulent strain T15. In addition, a 58% reduction in adherence to HEp-2 cells was observed
for HA9801 biofilm cells, compared with HA9801 planktonic cells. The 50% lethal dose (LD50) of biofilm cells was 40-fold greater than that of planktonic cells. Quantification of expression levels of known virulence genes by real-time PCR revealed that the transcription levels of the gdh, cps2 and mrp genes in biofilm cells were downregulated, while the sly and gapdh genes were upregulated. HA9801 biofilm and planktonic vaccines LY2835219 mouse provided 60% and 46% protection, respectively, when challenged with 50 times the LD50 of the HA9801 strain. These results suggest a possible connection between virulence and the ability of biofilm formation; cell adhesion, transcription levels and virulence properties are different between biofilm cells and planktonic cells. Furthermore, this work offers a novel insight into bacterium infection mechanisms, which suggests that a virulent strain may be able to decrease its virulence
by forming a biofilm so that it can achieve persistent infection in vivo. Streptococcus suis (SS) is a major pathogen of pigs worldwide and causes septicemia, meningitis, and endocarditis (Gottschalk et al., 1999), which colonizes the respiratory tract, particularly mafosfamide the tonsils and nasal cavities, as well as the genitals (Gottschalk et al., 2010). Among the 35 different serotypes, SS2 is known to be the most virulent and frequently isolated serotype (Principi & Marchisio, 1999). In addition, SS is believed to be a normal inhabitant of a variety of ruminants (Staats et al., 1997). The pig carrier rate is nearly 100%; however, mortality rates can reach 20% (Cloutier et al., 2003). SS binds to extracellular matrix proteins, including fibronectin and collagen (Esgleas et al., 2005), as well as to endothelial and epithelial cells (Charland et al., 2000; Benga et al., 2004), but the mechanisms by which the bacterium invades, infects, and incubates the host are unclear.