RRC ID 21087
著者 Kuno S, Yoshida T, Kaneko T, Sako Y.
タイトル Intricate interactions between the bloom-forming cyanobacterium Microcystis aeruginosa and foreign genetic elements, revealed by diversified clustered regularly interspaced short palindromic repeat (CRISPR) signatures.
ジャーナル Appl Environ Microbiol
Abstract Clustered regularly interspaced short palindromic repeats (CRISPR) confer sequence-dependent, adaptive resistance in prokaryotes against viruses and plasmids via incorporation of short sequences, called spacers, derived from foreign genetic elements. CRISPR loci are thus considered to provide records of past infections. To describe the host-parasite (i.e., cyanophages and plasmids) interactions involving the bloom-forming freshwater cyanobacterium Microcystis aeruginosa, we investigated CRISPR in four M. aeruginosa strains and in two previously sequenced genomes. The number of spacers in each locus was larger than the average among prokaryotes. All spacers were strain specific, except for a string of 11 spacers shared in two closely related strains, suggesting diversification of the loci. Using CRISPR repeat-based PCR, 24 CRISPR genotypes were identified in a natural cyanobacterial community. Among 995 unique spacers obtained, only 10 sequences showed similarity to M. aeruginosa phage Ma-LMM01. Of these, six spacers showed only silent or conservative nucleotide mutations compared to Ma-LMM01 sequences, suggesting a strategy by the cyanophage to avert CRISPR immunity dependent on nucleotide identity. These results imply that host-phage interactions can be divided into M. aeruginosa-cyanophage combinations rather than pandemics of population-wide infectious cyanophages. Spacer similarity also showed frequent exposure of M. aeruginosa to small cryptic plasmids that were observed only in a few strains. Thus, the diversification of CRISPR implies that M. aeruginosa has been challenged by diverse communities (almost entirely uncharacterized) of cyanophages and plasmids.
巻・号 78(15)
ページ 5353-60
公開日 2012-8-1
DOI 10.1128/AEM.00626-12
PII AEM.00626-12
PMID 22636003
PMC PMC3416447
MeSH Bacteriophages / genetics* Base Sequence Computational Biology DNA, Intergenic / genetics* Genotype Host-Pathogen Interactions Inverted Repeat Sequences / genetics* Japan Microcystis / genetics* Microcystis / metabolism Microcystis / virology* Molecular Sequence Data Multilocus Sequence Typing Plasmids / genetics Polymerase Chain Reaction / methods Sequence Analysis, DNA Species Specificity
IF 4.016
引用数 30
WOS 分野 BIOTECHNOLOGY & APPLIED MICROBIOLOGY MICROBIOLOGY
リソース情報
藻類 NIES-87 NIES-102 NIES-298