Project description:Ammonia-oxidizing archaea (AOA) are among the most abundant microorganisms and key players in the global nitrogen and carbon cycles. They share a common energy metabolism but represent a heterogeneous group with respect to their environmental distri- bution and adaptions, growth requirements, and genome contents. We report here the genome and proteome of Nitrososphaera viennensis EN76, the type species of the archaeal class Nitrososphaeria of the phylum Thaumarchaeota encompassing all known AOA. N. viennensis is a soil organism with a 2.52-Mb genome and 3,123 predicted protein-coding genes. Proteomic analysis revealed that nearly 50% of the predicted genes were translated under standard laboratory growth conditions. Comparison with genomes of closely related species of the predominantly terrestrial Nitrososphaerales as well as the more streamlined marine Nitrosopumilales (Candidatus order) and the acidophile Nitrosotalea devanaterra revealed a core genome of AOA comprising 860 genes, which allowed for the reconstruction of central metabolic pathways common to all known AOA and expressed in the N. viennensis and Nitrosopelagicus brevis proteomes. Concomitantly, we were able to identify candidate proteins for as yet unidentified crucial steps in central metabolisms. In addition to unraveling aspects of core AOA metabolism, we identified specific metabolic innovations associated with the Nitrososphaerales mediating growth and survival in the soil milieu, including the capacity for biofilm formation, cell surface modifications and cell adhesion, and carbohydrate conversions as well as detoxification of aromatic compounds and drugs.
Project description:This study evaluated the transcriptional reprogramming of a susceptible genotype (Pera sweet orange) challenged with the pathogenic bacteria Candidatus Liberibacter americanus (CaLam), using a customized 385K microarray containing about 32,000 unigene transcripts. For the microarray experiment were used symptomatic leaves from two Pera sweet orange plants inoculated with either bark or bud pieces infected with Candidatus Liberibacter americanus and two non-infected control plants.
Project description:We seqeunced mRNA from the bacterial pathogen 'Candidatus Liberibacter solanacearum" during its association with the psyllid vector Bactericera cockerelli.
Project description:HLB is suggested to be caused by the phloem-limited fastidious prokaryotic α-proteobacterium “Candidatus Liberibacter spp.” Previous studies focused on the proteome and transcriptome analyses of citrus 5 to 35-week-after “Ca. L. spp.” inoculation. In this study, gene expression profiles was analyzed using mandarin of Citrus reticulate Blanco cv. jiaogan leaves after 2-year infection with “Ca. L. asiaticus”. The Affymetrix GeneChip® citrus genome were applied to study the molecular pathways mediated by “Ca. L. asiaticus” inoculated 3-year-old jiaogan seedlings. Each of them was graft-inoculated with one sweet orange scions with or without “Ca. L. asiaticus” in Dectember, 2009. RNA samples from three mandarin trees infected with 'Candidatus Liberibacter asiaticus' and three uninfected trees were used for affymatrix genochip
