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Whole genome comparison of a large collection of mycobacteriophages reveals a continuum of phage genetic diversity.

ABSTRACT: The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences. However, amino acid sequence comparisons show pervasive genomic mosaicism, and quantification of inter-cluster and intra-cluster relatedness reveals a continuum of genetic diversity, albeit with uneven representation of different phages. Furthermore, rarefaction analysis shows that the mycobacteriophage population is not closed, and there is a constant influx of genes from other sources. Phage isolation and analysis was performed by a large consortium of academic institutions, illustrating the substantial benefits of a disseminated, structured program involving large numbers of freshman undergraduates in scientific discovery.

SUBMITTER: Pope WH

PROVIDER: S-EPMC4408529 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Whole genome comparison of a large collection of mycobacteriophages reveals a continuum of phage genetic diversity.

Pope Welkin H WH Bowman Charles A CA Russell Daniel A DA Jacobs-Sera Deborah D Asai David J DJ Cresawn Steven G SG Jacobs William R WR Hendrix Roger W RW Lawrence Jeffrey G JG Hatfull Graham F GF

eLife 20150428

The bacteriophage population is large, dynamic, ancient, and genetically diverse. Limited genomic information shows that phage genomes are mosaic, and the genetic architecture of phage populations remains ill-defined. To understand the population structure of phages infecting a single host strain, we isolated, sequenced, and compared 627 phages of Mycobacterium smegmatis. Their genetic diversity is considerable, and there are 28 distinct genomic types (clusters) with related nucleotide sequences ...[more]

PMID: 25919952

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Dataset Information

Whole genome comparison of a large collection of mycobacteriophages reveals a continuum of phage genetic diversity.

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Whole genome comparison of a large collection of mycobacteriophages reveals a continuum of phage genetic diversity.

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