Submitted to: DNA and Cell Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 1, 2003
Publication Date: November 1, 2003
Citation: Davis, R.E., Jomantiene, R., Zhao, Y., Dally, E.L. 2003. Folate biosynthesis pseudogenes, folp and folk, and an o-sialoglycoprotein endopeptidase gene homolog in the phytoplasma genome. DNA and Cell Biology. 22(11):697-706. Interpretive Summary: Phytoplasmas are tiny bacteria that cause many serious diseases in plants around the world. Each phytoplasma cell is surrounded by a single membrane. In this way, they are like mycoplasmas-their relatives that cause diseases of animals, and spiroplasmas-relatives that include pathogens of plants. Phytoplasma cells are among the smallest cells known. In addition, phytoplasmas have some of the smallest known genomes, that is, they possess a very small number of genes. To understand how phytoplasmas survive inside their plant and insect hosts and also cause diseases in spite of their small gene complement, we are comparing genes in phytoplasma with genes in other bacteria, including mycoplasma and spiroplasma. We have found that genes needed for the synthesis of an essential vitamin were present in ancestors of phytoplasma but have been destroyed in phytoplasma. We have also found that phytoplasma contains a gene for a protein-digesting enzyme that may aid the phytoplasma to invade its hosts. These findings will be of interest to scientists who wish to understand the evolution of phytoplasmas and the mechanisms by which phytopalsmas cause disease.