In conclusion, our findings support the hypothesis of the acquisition of genomic find more regions from other
pathogenic bacteria (E. coli or others) by horizontal transfers and reflect the genomic plasticity of EHEC or even E. coli strains. This variation in the genome contents of E. coli, suggested as a evolutionary strategy to better survive by Mokady et al. (2005), could lead to serious problems in public health and to the emergence of highly virulent new strains if one strain could acquire several strong virulence systems from different pathogenic bacteria, as it was dramatically illustrated by the 2011 Shiga toxin–producing E. coli O104:H4 German outbreak (Denamur, 2011; Rasko et al., 2011). During this study, Marjorie Bardiau was a PhD fellow of the ‘Fonds pour
la formation à la Recherche dans l’Industrie et dans l’Agriculture’ (FRIA). This study was funded by the Federal http://www.selleckchem.com/products/mitomycin-c.html Public Service of Health, Food Chain Safety and Environment (contract RF 6172), the European Network of Excellence EADGENE (European Animal Disease Genomics Network of Excellence for Animal Health and Food Safety) for the sequencing, and a grant ‘Crédits aux chercheurs’ FNRS (Fonds de Recherche Scientifique) 2008, no. 1363. “
“In silico analyses of several laccase promoter sequences have shown the presence of many different responsive elements differentially distributed along the promoter sequences. Analysis of Pleurotus ostreatus laccase promoter poxa1b extending around 1400-bp upstream of the start codon showed the presence of several putative response elements, such as 10 metal-responsive elements. Development of a system for in vivo analysis of P. ostreatus laccase promoter poxa1b by enhanced green fluorescent protein expression all was carried out, based on a polyethylene glycol–mediated procedure for fungal transformation.
Quantitative measurement of fluorescence expressed in P. ostreatus transformants grown in the presence and in the absence of copper sulfate was performed, demonstrating an increase in expression level induced by the metal. Twelve putative laccase genes have been identified in the recently sequenced Pleurotus ostreatus genome (http://www.jgi.doe.gov/sequencing/why/50009.html), one of which is annotated as a ferroxidase-like. The promoter regions of all the 11 P. ostreatus laccase genes, extending 500-bp upstream of the start codon, have been analyzed, revealing the presence of several putative response elements, differentially distributed along the promoter sequences (Piscitelli et al., 2011). All the analyzed P. ostreatus laccase promoters contain putative metal-responsive elements (MREs) with sequence homology to those reported in ascomycetous yeast.