Structure and Genetic Content of the Megaplasmids of Neurotoxigenic Clostridium butyricum Type E Strains from Italy

• DOI: 10.1371/journal.pone.0071324
• Publication Date: 2013-08-16T04:20:18Z
• Authors: Angelo Iacobino; Concetta Scalfaro; Giovanna Franciosa
• Keywords: Prophage; Clostridium butyricum

We determined the genetic maps of megaplasmids six neutoroxigenic Clostridium butyricum type E strains from Italy using molecular and bioinformatics techniques. The are circular, not linear as we had previously proposed. differently-sized share a region that includes structural, metabolic regulatory genes. In addition, found 168 kb is present only in larger two tested strains, whereas it absent smaller four remaining strains. unique to contains, among other features, locus for clustered regularly interspaced short palindromic repeats (CRISPR) CRISPR associated (cas) genes, i.e. bacterial adaptive immune system providing sequence-specific protection invading elements. Some spacer sequences neurotoxigenic C. showed homology prophage, phage plasmid closely related clostridia species or distant species, all sharing intestinal habitat, suggesting might be involved microorganism adaptation human animal environment. Besides, report here each distinct spacers partially matched DNA different prophages phages, at identical nucleotide locations. This suggests that, least E, potentially able recognize same conserved sequence elements, besides targeting encountered DNA, currently predicted locus. Thus, results this study introduce possibility loci can provide resistance wider range elements than appreciated. Whether more advantageous peculiar maintain lose CRISPR-cas remains an open question.