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In May of 2012, eggplant (Solanum melongena) plants in an experimental research plot located at Zamorano in the Department of Francisco Morazán, Honduras, were observed with symptoms that included leaf chlorosis and cupping, overall stunting, and production of small and malformed fruits. The research plot was planted next to a commercial tomato field heavily infested with the psyllid Bactericera cockerelli, a vector of ‘Candidatus Liberibacter solanacearum’ (1,2,3). This bacterium severely affects potato and other solanaceous species and is the putative causal agent of zebra chip disease (2,3). The plot was planted with the eggplant variety ‘China’ and about 25% of the plants were symptomatic. A total of 10 eggplant samples, including five symptomatic and five asymptomatic plants, were collected from the plot. Total DNA was extracted from the leaf tissue of each of the collected plants with the cetyltrimethylammonium bromide (CTAB) buffer extraction method (1). The DNA samples were then tested by PCR using specific primer sets OA2/OI2c and OMB 1482f/2086r to amplify a portion of 16S rDNA and the outer membrane protein (OMB) genes, respectively, of ‘Ca. L. solanacearum’ (1,2). OMB gene and 16S rDNA fragments of 605 and 1,168 bp, respectively, were amplified from the DNA of two of the five (40%) symptomatic plants with each primer set, indicating the presence of ‘Ca. L. solanacearum.’ No ‘Ca. L. solanacearum’ was detected in the five asymptomatic plants with either primer sets. DNA amplicons with both primer sets were cloned from the DNA of the two ‘Ca. L. solanacearum’-positive plant samples and four clones of each of the four amplicons were sequenced. BLASTn analysis of the 16S rDNA resulted in two independent but related consensus sequences (deposited in GenBank as Accession Nos. KF188224 and KF188225) and were 99% similar to each other. The two sequences showed 99 to 100% identity to a number of 16S rDNA sequences of ‘Ca. L. solanacearum’ in Genbank, including accessions HM245242, FJ811596, and KC768319. For the OMB amplicons, a single consensus sequence was obtained following clone sequencing and was deposited in GenBank as accession KF188229. BLASTn analysis of the sequence indicated that it was 100% identical to several OMB sequences of ‘Ca. L. solanacearum’ in GenBank, including accessions KC768331 and CP002371. To our knowledge, this is the first report of ‘Ca. L. solanacearum’ associated with eggplant in Honduras. Eggplant is an economically important commodity in Central America and serious damage to this crop due to this plant pathogen could expand throughout the region, especially if its insect vector B. cockerelli is not properly managed. ‘Ca. L. solanacearum’ has also caused millions of dollars in losses to potato and several other solanaceous crops in the United States, Mexico, Central America, and New Zealand (2,3). In addition, this bacterium severely damages carrot crops in Europe, where it is transmitted to carrot by the psyllids Trioza apicalis and B. trigonica (3,4). It is imperative that both ‘Ca. L. solanacearum’ and its insect vectors be effectively monitored and managed to minimize their threat to economically important vegetable crops in many parts of the world. References: (1) J. M. Crosslin et al. Southwest. Entomol. 36:125, 2011. (2) L. W. Liefting et al. Plant Dis. 93:208, 2009. (3) J. E. Munyaneza. Am. J. Pot. Res. 89:329, 2012. (4) J. E. Munyaneza et al. J. Econ. Entomol. 103:1060, 2010.

AbstractBackgroundDuring a two year period, a 27-year-old female veterinarian experienced migraine headaches, seizures, including status epilepticus, and other neurological and neurocognitive abnormalities. Prior to and during her illness, she had been actively involved in hospital-based work treating domestic animals, primarily cats and dogs, in Grenada and Ireland and anatomical research requiring the dissection of wild animals (including lions, giraffe, rabbits, mongoose, and other animals), mostly in South Africa. The woman reported contact with fleas, ticks, lice, biting flies, mosquitoes, spiders and mites and had also been scratched or bitten by dogs, cats, birds, horses, reptiles, rabbits and rodents. Prior diagnostic testing resulted in findings that were inconclusive or within normal reference ranges and no etiological diagnosis had been obtained to explain the patient’s symptoms.MethodsPCR assays targetingAnaplasmaspp.Bartonellaspp. and hemotopicMycoplasmaspp. were used to test patient blood samples. PCR positive amplicons were sequenced directly and compared to GenBank sequences. In addition,Bartonellaalpha Proteobacteria growth medium (BAPGM) enrichment blood culture was used to facilitate bacterial growth andBartonellaspp. serology was performed by indirect fluorescent antibody testing.ResultsAnaplasma platys, Bartonella henselaeandCandidatusMycoplasma haematoparvum DNA was amplified and sequenced from the woman’s blood, serum or blood culture samples. Her serum was variably seroreactive to severalBartonellasp. antigens. Despite symptomatic improvement, six months of doxycycline most likely failed to eliminate theB. henselaeinfection, whereasA. platysandCandidatusM. haematoparvum DNA was no longer amplified from post-treatment samples.ConclusionsAs is typical of many veterinary professionals, this individual had frequent exposure to arthropod vectors and near daily contact with persistently bacteremic reservoir hosts, including cats, the primary reservoir host forB. henselae,and dogs, the presumed primary reservoir host forA. platysandCandidatusMycoplasma haematoparvum. Physicians caring for veterinarians should be aware of the occupational zoonotic risks associated with the daily activities of these animal health professionals.

AbstractBackgroundHuanglongbing (HLB) is a worldwide devastating disease of citrus. There are no effective control measures for this newly emerging but century-old disease. Previously, we reported a combination of Penicillin G and Streptomycin was effective in eliminating or suppressing the associated bacterium, ‘CandidatusLiberibacter asiaticus’ (Las).ResultsHere we report the bacterial composition and community structure in HLB-affected citrus plants during a growing season and while being treated with antibiotic combinations PS (Penicillin G and Streptomycin) and KO (Kasugamycin and Oxytetracycline) using the Phylochip™ G3 array. Both antibiotic treatments resulted in significantly lower Las bacterial titers (Pr<0.05) and hybridization scores. Of the 50,000+ available operational taxonomic units (OTUs) on PhyloChip™ G3, 7,028 known OTUs were present in citrus leaf midribs. These OTUs were from 58 phyla, of which five contained 100 or more OTUs,Proteobacteria(44.1%), Firmicutes(23.5%),Actinobacteria(12.4%),Bacteroidetes(6.6%) andCyanobacteria(3.2%). In the antibiotic treated samples, the number of OTUs decreased to a total of 5,599. The over-all bacterial diversity decreased with the antibiotic treatments, as did the abundance of 11 OTUs withinProteobacteria,Firmicutes,BacteroidetesandPlanctomycetes. Within theProteobacteria, ten OTUs representing the classγ-proteobacteria increased in abundance after four months of treatment, when the Las bacterium was at its lowest level in the HLB-affected citrus field plants.ConclusionsOur data revealed thatProteobacteriawas constantly the dominant bacterial phylum recovered from citrus leaf midribs, with the α-proteobacterial and the γ-proteobacterial classes vying for prevalence. In addition, the level of bacterial diversity found in the leaf midribs of field citrus was greater than previously described. Bacterial cells in close proximity may be able to modify their microenvironment, making the composition of the microbial community an important factor in the ability of Las to cause HLB progression. A low Las level was seen as an annual fluctuation, part of the bacterial population dynamics, and as a response to the antibiotic treatments.

Abstract Members of the genus Candidatus Accumulibacter are important in many wastewater treatment systems performing enhanced biological phosphorus removal (EBPR). The Accumulibacter lineage can be subdivided phylogenetically into multiple clades, and previous work showed that these clades are ecologically distinct. The complete genome of Candidatus Accumulibacter phosphatis strain UW-1, a member of Clade IIA, was previously sequenced. Here, we report a draft genome sequence of Candidatus Accumulibacter spp. strain UW-2, a member of Clade IA, assembled following shotgun metagenomic sequencing of laboratory-scale bioreactor sludge. We estimate the genome to be 80–90% complete. Although the two clades share 16S rRNA sequence identity of >98.0%, we observed a remarkable lack of synteny between the two genomes. We identified 2317 genes shared between the two genomes, with an average nucleotide identity (ANI) of 78.3%, and accounting for 49% of genes in the UW-1 genome. Unlike UW-1, the UW-2 genome seemed to lack genes for nitrogen fixation and carbon fixation. Despite these differences, metabolic genes essential for denitrification and EBPR, including carbon storage polymer and polyphosphate metabolism, were conserved in both genomes. The ANI from genes associated with EBPR was statistically higher than that from genes not associated with EBPR, indicating a high selective pressure in EBPR systems. Further, we identified genomic islands of foreign origins including a near-complete lysogenic phage in the Clade IA genome. Interestingly, Clade IA appeared to be more phage susceptible based on it containing only a single Clustered Regularly Interspaced Short Palindromic Repeats locus as compared with the two found in Clade IIA. Overall, the comparative analysis provided a genetic basis to understand physiological differences and ecological niches of Accumulibacter populations, and highlights the importance of diversity in maintaining system functional resilience.