High impact information on Phytoplasma

• The infection by phytoplasma in C. roseus leaves causes an increase of metabolites related to the biosynthetic pathways of phenylpropanoids or terpenoid indole alkaloids: chlorogenic acid, loganic acid, secologanin, and vindoline [1].
• In situ RNA hybridization analyses revealed that TAG1 transcripts were restricted to the same floral meristem territories in healthy and infected tomatoes, indicating that tissue-specific expression of TAG1 was not affected by the stolbur phytoplasma infection [2].
• The first group comprises genes that are up-regulated by phytoplasma presence: in particular, a gene encoding the heat-shock protein HSP-70, a gene encoding a metallothionein (MT) and another homologous to the EST 673 cDNA clone of P. armeniaca, whose function was unknown [3].
• Genes coding for elongation factors G (fus) and Tu (tuf) of the non-culturable apple proliferation (AP) phytoplasma were cloned and sequenced [4].
• This study suggests that the Sec system operates in this phytoplasma to export OY Amp [5].

Chemical compound and disease context of Phytoplasma

• The findings suggest that the phytoplasma lacks capacity for de novo folate biosynthesis and possesses a transport system for absorption of preformed folate from host cells [6].
• Since no KPA precipitates were visible in the phloem and on phytoplasma cells, it is likely that Ca(2+) ions are not directly involved in phytoplasma replication, but, in infected cells is a response to the pathogen indicative of a higher Ca(2+) in the plasmalemma [7].
• The transformants were assayed for chloramphenicol acetyltransferase activity, showing that the phytoplasma promoter is efficiently expressed in a B. subtilis background [8].
• The potassium pyroantimonate (KPA) Ca(2+) precipitation technique, X-ray microanalysis and Electron Energy Loss Spectroscopy carried out by transmission electron microscopy were used to analyze the Ca(2+) distribution in Catharanthus roseus L. leaves infected with phytoplasmas belonging to different taxonomic groups, and in phytoplasma cells [7].

Biological context of Phytoplasma

• Two different thymidylate kinase gene homologues, including one that has catalytic activity, are encoded in the onion yellows phytoplasma genome [9].
• Two homologues of bacterial thymidylate kinase genes were identified in a genomic library of the onion yellows (OY) phytoplasma, a plant pathogen that inhabits both plant phloem and the organs of insects [9].
• One study found pseudogene homologs of folP and folK, obviating folate synthesis in "Candidatus Phytoplasma asteris"-related strain CPh, whereas, a separate study found intact genes encoding a complete folate biosynthesis pathway in "Ca. Phytoplasma asteris"-related strain OY [10].
• Restriction fragment length polymorphism (RFLP) and sequence analysis indicated that PPT phytoplasma belongs to the 16SrI group and PHS phytoplasma fits in the 16SrII group [11].

Gene context of Phytoplasma

• Phylogenetic analysis of representative genes showed that the TBB phytoplasma grouped with the mycoplasmas with the exception of the TBB phytoplasma secA gene, which grouped with the onion yellows phytoplasma [12].
• Relative quantification of chrysanthemum yellows (16Sr I) phytoplasma in its plant and insect host using real-time polymerase chain reaction [13].
• We report the sequence and catalytic properties of RNase P RNA from the phytoplasma causing apple proliferation disease [14].
• Two most important diseases associated with parthenium were a rust disease, caused by Puccinia abrupta var. partheniicola, and a phyllody disease, caused by a phytoplasma of fababean phyllody (PBP) phytoplasma group [15].

References