Related Experiment Video

Updated: May 10, 2026

Multi-locus Variable-number Tandem-repeat Analysis of the Fish-pathogenic Bacterium Yersinia ruckeri by Multiplex PCR and Capillary Electrophoresis
10:33

Multi-locus Variable-number Tandem-repeat Analysis of the Fish-pathogenic Bacterium Yersinia ruckeri by Multiplex PCR and Capillary Electrophoresis

Published on: June 17, 2019

Ribosomal DNA analyses reveal greater sequence variation in Polymyxa species than previously thought and indicate the

Madeleine J Smith1, Michael J Adams, Elaine Ward

  • 1Department of Plant Pathology and Microbiology, Rothamsted Research, Harpenden, Hertfordshire AL5 2JQ, UK.

Environmental Microbiology Reports
|June 13, 2013
PubMed

Insights

Polymyxa graminis, a plant pathogen vector, exhibits greater genetic diversity than previously known, with new evidence suggesting it transmits important crop viruses. This finding impacts understanding of plant disease spread and management strategies.

Area of Science:

  • * Plant Pathology and Molecular Phylogenetics
  • * Study of obligate parasitic protozoa and their role in agriculture

Background:

  • * Polymyxa species are significant vectors of plant viruses affecting vital crops.
  • * These obligate parasites are not well-characterized, hindering disease spread assessment.
  • * Understanding Polymyxa diversity is crucial for managing virus transmission.

Purpose of the Study:

  • * To analyze ribosomal DNA of Polymyxa isolates to understand their diversity.
  • * To investigate geographical distribution, host range, and virus associations.
  • * To clarify the potential for spread of Polymyxa-vectored plant diseases.

Main Methods:

  • * Ribosomal DNA analysis of Polymyxa isolates from diverse locations, hosts, and virus associations.
  • * Internal Transcribed Spacer 2 (ITS2) structural analysis for species differentiation.
  • * Sequence variation analysis within known Polymyxa subgroups (ribotypes).

Main Results:

  • * Polymyxa graminis isolates display significant genetic variation, suggesting multiple species within known ribotypes.
  • * Ribotype I, previously not confirmed, was found to transmit Soil-borne wheat mosaic virus (SBWMV) and Soil-borne cereal mosaic virus (SBCMV), alongside Ribotype II.
  • * New host associations were identified, including Polymyxa betae in wheat, and tropical Ribotype III-like sequences were detected in US wheat.

Conclusions:

  • * Polymyxa diversity is underestimated, impacting disease vectoring potential.
  • * Ribotype I's role in transmitting SBWMV/SBCMV broadens the scope of potential disease spread.
  • * The limited variation in Polymyxa betae suggests other factors are responsible for sugar beet virus resistance changes.

More Related Videos

Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency18:10

Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency

Published on: June 16, 2011

Single Nucleotide Polymorphism-sensitive FISH Detection of Locus-specific Ribosomal RNA Transcription in Drosophila melanogaster04:59

Single Nucleotide Polymorphism-sensitive FISH Detection of Locus-specific Ribosomal RNA Transcription in Drosophila melanogaster

Published on: March 28, 2025

Related Concept Videos

Modern Molecular Taxonomy01:29

Modern Molecular Taxonomy

Advancements in molecular biology have revolutionized the identification and characterization of bacteria, with multiple methods leveraging DNA sequencing for enhanced precision. As sequencing technologies improve and costs decline, these approaches are increasingly used in clinical, environmental, and evolutionary studies.Multilocus Sequence Typing (MLST) examines several housekeeping genes, essential chromosomal genes encoding cellular functions, to distinguish strains. Approximately...
Viruses of Archaea01:29

Viruses of Archaea

Archaeal viruses play a crucial role in the ecosystems of extremophilic archaea, particularly those belonging to the phyla Euryarchaeota and Crenarchaeota. By shaping host evolution and facilitating gene transfer, these viruses influence microbial communities and contribute to genetic diversity in extreme environments. The archaea they infect thrive in acidic hot springs and hydrothermal vents characterized by high temperatures and low pH. Archaeal viruses exhibit remarkable structural...
Viral Mutations00:36

Viral Mutations

A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material for adaptive...
Applications of Molecular Taxonomy01:20

Applications of Molecular Taxonomy

Molecular taxonomy has revolutionized the understanding and classification of bacteria, providing precise insights into their diversity, evolutionary relationships, and ecological roles. By utilizing molecular techniques such as DNA sequencing and fingerprinting, researchers have made significant strides in various fields related to bacterial studies.Resolving Taxonomic AmbiguitiesMolecular taxonomy has been instrumental in distinguishing closely related bacterial species initially thought to...
Size and Structure of Viral Genomes01:26

Size and Structure of Viral Genomes

Viral genomes exhibit remarkable diversity in size, structure, and composition, influencing their replication strategies and interactions with host cells. These genomes consist of either DNA or RNA and may be linear or circular. Additionally, they can be single-stranded or double-stranded, with each configuration affecting how the virus propagates within a host. RNA viruses, for instance, generally have smaller genomes than DNA viruses, a factor that contributes to their high mutation rates and...
Viral Recombination00:57

Viral Recombination

Cells are sometimes infected by more than one virus at once. When two viruses disassemble to expose their genomes for replication in the same cell, similar regions of their genomes can pair together and exchange sequences in a process called recombination. Alternatively, viruses with segmented genomes can swap segments in a process called reassortment.