|Lee, Ing ming|
Submitted to: Phytopathology
Publication Type: Abstract only
Publication Acceptance Date: 3/11/2006
Publication Date: 4/12/2006
Citation: Davis, R.E., Jomantiene, R., Lee, I., Zhao, Y., Hammond, R., Shao, J.Y., Dally, E.L., Dawe, A., Davis, K., Nuss, D. 2006. An acholeplasma genome encodes enzymes with the potential to degrade and utilize plant cell wall components. Phytopathology. Interpretive Summary:
Technical Abstract: Phytoplasmas and Acholeplasma spp. are wall-less bacteria classified in class Mollicutes. Phylogenetic analyses based on ribosomal RNA have indicated that phytoplasmas descended from acholeplasma-like ancestors. Yet, little is known concerning genes that were lost and genes that were retained during the divergence of phytoplasmas and acholeplasmas from their last common ancestor (LCA). Whereas, phytoplasmas are obligately parasitic phytopathogens, known Acholeplasma spp. are apparently not obligate parasites in nature and have not been described as phytopathogenic. In silico reconstruction of the genome of their LCA could aid understanding of both Acholeplasma and phytoplasma evolution. Acholeplasma palmae was originally isolated from rotting tissues of a coconut palm (Cocos nucifera), but the precise nature of the association of this or other Acholeplasma spp. with plants has remained undetermined. We now report that the A. palmae genome contains nucleotide sequences potentially encoding putative enzymes involved in plant cell wall degradation and product assimilation, genes not previously found in the genomes of other members of class Mollicutes, including phytoplasmas. The results suggest that such genes were present in the phytoplasma-acholeplasma LCA genome and were lost in phytoplasma evolution. They further point to utilization of plant products by A. palmae and support the hypothesis that this acholeplasma may be capable of penetrating plant tissues as a secondary invader.