Project description:Background: The human pathogen Arcobacter butzleri is a member of the epsilon subdivision of the Proteobacteria and a close taxonomic relative of other established pathogens, such as Campylobacter jejuni and Helicobacter pylori. Here we present the complete genome sequence of the human clinical isolate, A. butzleri strain RM4018. Results: Arcobacter butzleri is a member of the Campylobacteraceae, but the majority of its proteome is most similar to those of Thiomicrospira denitrificans and Wolinella succinogenes, both members of the Helicobacteraceae. In addition, many of the genes and pathways described here, e.g. those involved in signal transduction and sulfur metabolism, have been identified previously within the epsilon subdivision only in T. denitrificans and/or W. succinogenes, or are unique to the subdivision. The analyses indicated also that a large proportion of the A. butzleri genome is devoted to growth and survival under diverse environmental conditions, with a large number of respiration-associated proteins, signal transduction and chemotaxis proteins and proteins involved in DNA repair and adaptation. To investigate the genomic diversity of A. butzleri strains, we constructed an A. butzleri DNA microarray comprising 2238 genes from strain RM4018. Comparative genomic indexing analysis of 12 additional A. butzleri strains identified both the core genes of A. butzleri and intraspecies hypervariable regions, where < 70% of the genes were present in at least two strains. Conclusion: The presence of environmentally-associated pathways and loci, as well as genes associated with virulence indicates that this free-living, water-borne organism A. butzleri can be classified rightfully as an emerging pathogen. Keywords: comparative genomic hybridization
Project description:The Breviatea form a lineage of free-living protists that emerged over 800 million years ago as a sister clade to opistokonta, comprising animals and fungi. Breviates conserved the ability to thrive in absence of oxygen which was an important adaptation to the low oceanic oxygen-levels that prevailed by that time. We previously found that the novel breviate, Lenisia limosa, gen. et sp. nov., was opportunistically colonized by relatives of animal-associated Arcobacter. Here we used differential proteomics to investigate how the presence/absence of symbiotic Arcobacter is manifested in Lenisia limosa's proteome. Vice versa, we also measured how symbiosis is reflected in Arcobacter's proteome. The results provide a resource to characterize the molecular underpinnings of a novel protist-prokaryote symbiosis.
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.
