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In August of 2011, potato (Solanum tuberosum) tubers grown in the lower Columbia Basin of southern Washington State and northern Oregon were observed with internal discolorations suggestive of zebra chip disease (ZC). Symptoms included brown spots, streaks, and stripes in and near the vascular tissue, typical of ZC (1). Symptoms were observed in cvs. Alturas, Russet Norkotah, Pike, Ranger Russet, Umatilla Russet, and Russet Burbank. Foliar symptoms on plants that produced symptomatic tubers included purple discoloration in upper leaves, leaf rolling, axial bud elongation, chlorosis, leaf scorch, and wilt. Tissue was taken from two symptomatic tubers each of cvs. Alturas and Russet Norkotah, three tubers of cv. Umatilla Russet, and one tuber of cv. Pike. These tubers were tested by PCR for “Candidatus Liberibacter solanacearum”, an unculturable alphaproteobacterium associated with ZC (1,4). Primers specific for the 16S rDNA were CLipoF (4) and OI2c (3), and primers OMB 1482f and 2086r were specific for the outer membrane protein (2). All of these samples, except one Umatilla tuber, were positive for the bacterium. The 16S rDNA and OMB amplicons from one symptomatic tuber each of Alturas (from Washington) and Pike (from Oregon) were cloned and three clones of each were sequenced. BLAST analysis of the consensus sequences confirmed “Ca. L. solanacearum”. The 16S sequences (1,071 bp) from the two tubers were identical and showed 99 to 100% identity to a number of 16S rDNA sequences of “Ca. L. solanaceaum” in GenBank (e.g., Accession Nos. HM246509 and FJ957897). The 16S rDNA sequences were deposited in GenBank as Accession Nos. JN848751 and JN848753. Consensus sequences of the two OMB clones (605 bp; deposited in GenBank as Accession Nos. JN848752 and JN848754) were identical and showed 97% identity to the two “Ca. L. solanacearum” OMB sequences in GenBank (Accession Nos. CP002371 and FJ914617). Potato psyllids (Bactericera cockerelli Sulc), the vector of “Ca. L. solanacearum”, were present in ZC-affected fields in Oregon and Washington and the bacterium was confirmed by PCR in 5 to 10% of 128 adult psyllids collected from two fields. On the basis of foliar and tuber symptoms, specific PCR amplification with two primer pairs, sequence analyses, and the presence of Liberibacter-infected potato psyllids, ZC and “Ca. L. solanacearum” are present in potatoes in Oregon and Washington State. Washington and Oregon together grow ~80,000 ha of potatoes. ZC has caused significant economic damage to potatoes in Texas, Mexico, Central America, and New Zealand (1). Therefore, ZC may pose a risk to agriculture in Oregon, Washington, and neighboring states. However, the potential for development of widespread and serious disease will depend upon the arrival time and number of infective potato psyllids entering the region. References: (1) J. M. Crosslin et al. Online publication. doi:10.1094/PHP-2010-0317-01-RV, Plant Health Progress, 2010. (2) J. M. Crosslin et al. Southwest. Entomol. 36:125, 2011. (3) S. Jagoueix et al. Mol. Cell. Probes 10:43, 1996. (4) G. A. Secor. Plant Dis. 93:574, 2009.

It has long been known that armored scale insects harbor endosymbiotic bacteria inside specialized cells called bacteriocytes. Originally, these endosymbionts were thought to be fungal symbionts but they are now known to be bacterial and have been named Uzinura diaspidicola. Bacteriocyte and endosymbiont distribution patterns within host insects were visualized using in situ hybridization via 16S rRNA specific probes. Images of scale insect embryos, eggs and adult scale insects show patterns of localized bacteriocytes in embryos and randomly distributed bacteriocytes in adults. The symbiont pocket was not found in the armored scale insect eggs that were tested. The pattern of dispersed bacteriocytes in adult scale insects suggest that Uzinura and Blattabacteria may share some homologous traits that coincide with similar life style requirements, such as dispersal in fat bodies and uric acid recycling.

ABSTRACT We present the genome sequence of “ Candidatus Mycoplasma haemominutum” strain Birmingham 1, a low-pathogenicity feline hemoplasma strain.

Abstract Adelgids (Insecta: Hemiptera: Adelgidae) are known as severe pests of various conifers in North America, Canada, Europe and Asia. Here, we present the first molecular identification of bacteriocyte-associated symbionts in these plant sap-sucking insects. Three geographically distant populations of members of the Adelges nordmannianae/piceae complex, identified based on coI and ef1alpha gene sequences, were investigated. Electron and light microscopy revealed two morphologically different endosymbionts, coccoid or polymorphic, which are located in distinct bacteriocytes. Phylogenetic analyses of their 16S and 23S rRNA gene sequences assigned both symbionts to novel lineages within the Gammaproteobacteria sharing <92% 16S rRNA sequence similarity with each other and showing no close relationship with known symbionts of insects. Their identity and intracellular location were confirmed by fluorescence in situ hybridization, and the names ‘Candidatus Steffania adelgidicola’ and ‘Candidatus Ecksteinia adelgidicola’ are proposed for tentative classification. Both symbionts were present in all individuals of all investigated populations and in different adelgid life stages including eggs, suggesting vertical transmission from mother to offspring. An 85 kb genome fragment of ‘Candidatus S. adelgidicola’ was reconstructed based on a metagenomic library created from purified symbionts. Genomic features including the frequency of pseudogenes, the average length of intergenic regions and the presence of several genes which are absent in other long-term obligate symbionts, suggested that ‘Candidatus S. adelgidicola’ is an evolutionarily young bacteriocyte-associated symbiont, which has been acquired after diversification of adelgids from their aphid sister group.

ABSTRACT “ Candidatus Methylomirabilis oxyfera” is a newly discovered denitrifying methanotroph that is unrelated to previously known methanotrophs. This bacterium is a member of the NC10 phylum and couples methane oxidation to denitrification through a newly discovered intra-aerobic pathway. In the present study, we report the first ultrastructural study of “ Ca . Methylomirabilis oxyfera” using scanning electron microscopy, transmission electron microscopy, and electron tomography in combination with different sample preparation methods. We observed that “ Ca . Methylomirabilis oxyfera” cells possess an atypical polygonal shape that is distinct from other bacterial shapes described so far. Also, an additional layer was observed as the outermost sheath, which might represent a (glyco)protein surface layer. Further, intracytoplasmic membranes, which are a common feature among proteobacterial methanotrophs, were never observed under the current growth conditions. Our results indicate that “ Ca . Methylomirabilis oxyfera” is ultrastructurally distinct from other bacteria by its atypical cell shape and from the classical proteobacterial methanotrophs by its apparent lack of intracytoplasmic membranes.