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Frequency of morphological phage descriptions

H W Ackermann1

  • 1Department of Microbiology, Faculty of Medicine, Laval University, Quebec, Canada.

Archives of Virology
|January 1, 1992
PubMed

Insights

Bacteriophages, viruses infecting bacteria, are diverse, with 96% being tailed. Their widespread presence across bacterial genera suggests a deep evolutionary connection.

Area of Science:

  • Microbiology
  • Virology
  • Bioinformatics

Background:

  • Bacteriophages (phages) are viruses that infect bacteria and archaea.
  • Over 4,000 phages have been described since 1960, classified by morphology and host range.
  • Phage diversity is extensive, encompassing 13 virus families and over 100 bacterial genera.

Purpose of the Study:

  • To catalog and analyze the diversity of described bacteriophages.
  • To understand the distribution patterns of phages across bacterial hosts.
  • To explore the evolutionary implications of phage-host relationships.

Main Methods:

  • Literature review and data compilation of described bacteriophages.
  • Classification of phages based on morphotype (e.g., tailed, cubic, filamentous, pleomorphic).
  • Analysis of phage host ranges, including bacterial and archaeal genera.

Main Results:

  • A total of 4,007 phages have been described, belonging to 13 virus families.
  • Approximately 96% of described phages possess tails, with Siphoviridae (long, noncontractile tails) comprising 60% of these.
  • Phages infect over 100 bacterial genera, exhibiting uneven distribution.
  • Tailed phages are the predominant morphotype, highlighting a conserved structural feature.

Conclusions:

  • Bacteriophage diversity is substantial, dominated by tailed morphotypes.
  • The broad host range and uneven distribution of phages suggest co-evolution with bacteria.
  • Phage classification and distribution data provide insights into microbial evolution and ecology.

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