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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
Current view on phytoplasma genomes and encoded metabolism
Michael Kube1, Jelena Mitrovic, Bojan Duduk
1Department of Crop and Animal Sciences, Humboldt-University of Berlin, Lentzeallee 55/57, 14195 Berlin, Germany. michael.kube@agrar.hu-berlin.de
Thescientificworldjournal
|May 3, 2012
Summary
Phytoplasmas, plant-infecting bacteria, have small genomes due to adaptation. Comparative genomics reveals genetic losses and gains, highlighting host specialization and potential alternative metabolic pathways.
Area of Science:
- Bacteriology
- Genomics
- Plant Pathology
Background:
- Phytoplasmas are specialized bacteria, obligate parasites of plant phloem and insects, notoriously difficult to cultivate in vitro.
- Understanding their genetic makeup is crucial due to their unique biology and impact on agriculture.
Purpose of the Study:
- To review and compare the gene content of four completely sequenced 'Candidatus Phytoplasma' genomes.
- To analyze evolutionary adaptations, genome organization, and functional differences among phytoplasma strains.
Main Methods:
- Comparative genomics of four 'Candidatus Phytoplasma' genomes: 'Ca. P. asteris' (OY-M, AY-WB), 'Ca. P. australiense,' and 'Ca. P. mali'.
- Analysis of genome size, G+C content, gene modules, and specific protein families.
Main Results:
- Phytoplasma genomes are small (<900 kb) with low G+C content (<28%), reflecting adaptation to nutrient-rich hosts.
- Genome reduction through gene loss is balanced by duplications and integrations, leading to instability.
- 'Ca. P. mali' exhibits distinct features, including chromosome organization and loss of glycolysis components, but shares a potential pyruvate/ATP generation pathway with others.
Conclusions:
- Comparative genomics highlights phytoplasma host adaptation via gene content variation, particularly in membrane and secreted proteins.
- Despite genome reduction and specialization, conserved pathways suggest resilience and adaptability.
- Further research into phytoplasma genomes can inform strategies for managing plant diseases caused by these pathogens.
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