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Title: Cylindrospermopsis raciborskii Virus and host: genomic characterization and ecological relevance
Summary

Cylindrospermopsis (Raphidiopsis) raciborskiiis an invasive, filamentous, nitrogen‐fixing cyanobacterium that forms frequent blooms in freshwater habitats. While viruses play key roles in regulating the abundance, production and diversity of their hosts in aquatic ecosystems, the role(s) of viruses in the ecology ofC. raciborskiiis almost unexplored. Progress in this field has been hindered by the absence of a characterized virus–host system inC. raciborskii. To bridge this gap, we sequenced the genome of CrV‐01T, a previously isolated cyanosiphovirus, and its host,C. raciborskiistrain Cr2010. Analyses suggest that CrV‐01T represents a distinct clade of siphoviruses infecting, and perhaps lysogenizing, filamentous cyanobacteria. Its genome contains unique features that include an intact CRISPR array and a 12 kb inverted duplication. Evidence suggests CrV‐01T recently gained the ability to infect Cr2010 and recently lost the ability to form lysogens. The cyanobacterial host contains a CRISPR‐Cas system with CRISPR spacers matching protospacers within the inverted duplication of the CrV‐01T genome. Examination of metagenomes demonstrates that viruses with high genetic identity to CrV‐01T, but lacking the inverted duplication, are present inC. raciborskiiblooms in Australia. The unique genomic features of the CrV/Cr2010 system offers opportunities to investigate in more detail virus–host interactions in an ecologically important bloom‐forming cyanobacterium.

 
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NSF-PAR ID:
10077984
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Environmental Microbiology
Volume:
21
Issue:
6
ISSN:
1462-2912
Page Range / eLocation ID:
p. 1942-1956
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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