title: Phytoplasmas and their interactions with hosts.
abstract: Phytoplasmas are bacteria without cell walls and are responsible for plant diseases that have large economic impacts. Knowledge of their biology is limited because they are uncultivable and experimentally inaccessible in their hosts. It is a mystery how these bacteria use the sugar-rich phloem sap in which they live and how they interact with the host. This makes it difficult to develop means to control them. Recently, the full genomes of two phytoplasmas have been sequenced, allowing new insights into their requirements. Phytoplasmas contain a minimal genome and lack genes coding for ATP synthases and sugar uptake and use, making them dependent on their host. This dependency can be exploited to elucidate the particular physiology of the phloem.
authors.affiliation: Department of Plant Biology, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Copenhagen, Denmark.
authors.forename: Nynne M
authors.initials: NM
authors.lastname: Christensen
authors.forename: Kristian B
authors.initials: KB
authors.lastname: Axelsen
authors.forename: Mogens
authors.initials: M
authors.lastname: Nicolaisen
authors.forename: Alexander
authors.initials: A
authors.lastname: Schulz
mesh_terms: D016680:Genome, Bacterial; D008564:Membrane Potentials; D010802:Phylogeny; D045582:Phytoplasma / Q000235:genetics / Q000472:pathogenicity / Q000502:physiology*; D010935:Plant Diseases / Q000382:microbiology*; D010944:Plants / Q000382:microbiology*