Genomics and genetics of Sulfolobus islandicus LAL14/1, a model hyperthermophilic archaeon. Issue 4 (April 2013)

• Record Type: Journal Article
• Authors: Jaubert, Carole; Danioux, Chloë; Oberto, Jacques; Cortez, Diego; Bize, Ariane; Krupovic, Mart; She, Qunxin; Forterre, Patrick; Prangishvili, David; Sezonov, Guennadi
• Is Part Of: Open biology. Volume 3:Issue 4(2013)
• Publication Date: 2013-04
• Subjects: Archaea -- Sulfolobus islandicus LAL14/1 -- genome analysis -- genetics -- CRISPR; Biology -- Periodicals; 570
• DOI: 10.1098/rsob.130010
• Languages: English
• ISSNs: 2046-2441

Abstract

Abstract : The 2 465 177 bp genome of Sulfolobus islandicus LAL14/1, host of the model rudivirus SIRV2, was sequenced. Exhaustive comparative genomic analysis of S. islandicus LAL14/1 and the nine other completely sequenced S. islandicus strains isolated from Iceland, Russia and USA revealed a highly syntenic common core genome of approximately 2 Mb and a long hyperplastic region containing most of the strain-specific genes. In LAL14/1, the latter region is enriched in insertion sequences, CRISPR (clustered regularly interspaced short palindromic repeats), glycosyl transferase genes, toxin–antitoxin genes and MITE (miniature inverted-repeat transposable elements). The tRNA genes of LAL14/1 are preferential targets for the integration of mobile elements but clusters of atypical genes (CAG) are also integrated elsewhere in the genome. LAL14/1 carries five CRISPR loci with 10 per cent of spacers matching perfectly or imperfectly the genomes of archaeal viruses and plasmids found in the Icelandic hot springs. Strikingly, the CRISPR_2 region of LAL14/1 carries an unusually long 1.9 kb spacer interspersed between two repeat regions and displays a high similarity to pING1-like conjugative plasmids. Finally, we have developed a genetic system for S. islandicus LAL14/1 and created Δ pyrEF and Δ CRISPR_1 mutants using double cross-over and pop-in/pop-out approaches, respectively. Thus, LAL14/1 is a promising model to study virus–host interactions and the CRISPR/Cas defence mechanism in Archaea.