In addition, the ssg mutation also significantly altered the exopolysaccharide composition devoid of fucose

and mannose. Based on the results of our analysis of sugar composition of exopolysaccharide, we speculate that the product Idelalisib cell line of ssg might be involved in the transfer of a specific sugar residue from its nucleotide-activated sugar precursor to the growing chain of exopolysaccharide as proposed above for the role of Ssg protein in lipopolysaccharide biosynthesis. The precise mechanism by which Ssg acts on O-antigen and exopolysaccharide biosynthesis deserves further study. Mutations that alter the lipopolysaccharide biosynthesis have been shown to affect motility and biofilm formation in many bacteria including P. aeruginosa and Stenotrophomonas maltophilia (Huang et al., 2006; Lindhout et al., 2009). As expected, the mutant SGI-1776 KL28Δssg exhibited many defects, especially in adhesion-related properties such as surface motility, circular pellicles, biofilm and aerial structure formation. The observed defects in the mutant strain are probably due to the cumulative effect of lipopolysaccharide truncation and altered exopolysaccharide composition. Thus, the ssg gene has important

relevance in the ecological fitness of this bacterium. Although homologs of Ssg are found in many plant and animal pathogenic Pseudomonas species, the reaction catalyzed by members of this glycosyltransferase family remains unknown at present (King et al., 2009). In conclusion, we have shown that the product encoded by ssg plays a critical role in lipopolysaccharide and exopolysaccharide biosynthesis in strain KL28. More work is required

before we can fully understand the biochemical activities of Ssg in lipopolysaccharide and/or exopolysaccharide biosynthesis pathways in Pseudomonas. PIK3C2G This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) grant funded by the Ministry of Education, Science and Technology (No. 2009-0073913 and 2007-0055799) and by Changwon National University in 2009–2010. Work in the lab of J.S.L. is funded by the Canadian Cystic Fibrosis Foundation, and J.S.L. is a holder of a Canada Research Chair award. “
“The thermophilic bacterium Thermus thermophilus HB27 is known for its highly efficient natural transformation system, which has become a model system to study the structure and function of DNA transporter in thermophilic bacteria. The DNA transporter is functionally linked to type IV pili (T4P), which are essential for twitching motility and adhesion to solid surfaces. However, the pilus structures themselves are dispensable for natural transformation. Here, we report that the cellular mRNA levels of the major structural subunit of the T4P, PilA4, are regulated by environmental factors. Growth of T. thermophilus in minimal medium or low temperature (55 °C) leads to a significant increase in pilA4 transcripts.