Trypanosomatids are increasingly recognized as prevalent in European honey bees (Apis mellifera) and by default are attributed to one recognized species, Crithidia mellificae Langridge and McGhee, 1967. We provide reference genetic and ultrastructural data for type isolates of C. mellificae (ATCC 30254 and 30862) in comparison with two recent isolates from A. mellifera (BRL and SF). Phylogenetics unambiguously identify strains BRL/SF as a novel taxonomic unit distinct from C. mellificae strains 30254/30862 and assign all four strains as lineages of a novel clade within the subfamily Leishmaniinae. In vivo analyses show strains BRL/SF preferably colonize the hindgut, lining the lumen as adherent spheroids in a manner identical to previous descriptions from C. mellificae. Microscopy images show motile forms of C. mellificae are distinct from strains BRL/SF. We propose the binomial Lotmaria passim n. gen., n. sp. for this previously undescribed taxon. Analyses of new and previously accessioned genetic data show C. mellificae is still extant in bee populations, however, L. passim n. gen., n. sp. is currently the predominant trypanosomatid in A. mellifera globally. Our findings require that previous reports of C. mellificae be reconsidered and that subsequent trypanosomatid species designations from Hymenoptera provide genetic support.

ABSTRACT. Nosema ceranae, a microsporidian parasite originally described from Apis cerana, has been found to infect Apis melllifera and is highly pathogenic to its new host. In the present study, data on the ultrastructure of N. ceranae, presence of N. ceranae-specific nucleic acid in host tissues, and phylogenetic relationships with other microsporidia species are described. The ultrastructural features indicate that N. ceranae possesses all of the characteristics of the genus Nosema. Spores of N. ceranae measured approximately 4.4 Â 2.2 mm on fresh smears. The number of coils of the polar filament inside spores was 18-21. Polymerase chain reaction (PCR) signals specific for N. ceranae were detected not only in the primary infection site, the midgut, but also in the tissues of hypopharyngeal glands, salivary glands, Malpighian tubules, and fat body. The detection rate and intensity of PCR signals in the fat body were relatively low compared with other examined tissues. Maximum parsimony analysis of the small subunit rRNA gene sequences showed that N. ceranae appeared to be more closely related to the wasp parasite, Nosema vespula, than to N. apis, a parasite infecting the same host.

We have developed commercially viable phytoremediation/phytomining technologies employing Alyssum Ni-hyperaccumulator species to quantitatively extract Ni from soils. The majority of Ni is stored either in Alyssum leaf epidermal cell vacuoles or in the basal portions only of the numerous stellate trichomes. Here, we report simultaneous and region-specific localization of high levels of Ni, Mn, and Ca within Alyssum trichomes as determined by scanning electron microscopy/energy-dispersive X-ray analysis (SEM/EDX). Plants were grown in high Ni soil, achieving up to 48 400 microg g(-1) Ni in total leaf concentration; however, Ca and Mn were not enriched in the experimental soils. The region-specific localization of hyperaccumulated Ca, Mn, and Ni occurred in three soil types, five Alyssum species/ecotypes, and over a wide range of soil Ni concentrations. The metal concentration in the trichome basal compartment was approximately 15-20% dry weight, the highest ever reported for healthy vascular plant tissue.

Changes in transcript accumulation for cell wall-modifying proteins were examined in excised soybean root pieces colonized by soybean cyst nematodes (SCN), Heterodera glycines, using RT-PCR and soybean Affymetrix GeneChips. Sequence-specific PCR primer pairs were prepared from sequence data for core sequences in the GenBank soybean database and consensus sequences derived from the assembly of soybean ESTs. In addition, to identify previously uncharacterized soybean transcripts, degenerate primers were prepared for conserved motifs in cellulases (endo-1,4-beta-glucanases, EGases) and polygalacturonases (PGs) and these were used to amplify segments of transcripts that were then extended with 3' and 5' RACE. Several novel EGase and PG transcripts were identified. Gene expression patterns were determined by real-time RT-PCR for 11 EGases, three expansins (EXPs), 14 PGs, two pectate lyases (PLs), and two xyloglucan endotransglucosylase/hydrolases (XTHs) in soybean roots inoculated with SCN, non-inoculated roots, serial dissections of root tips, leaf abscission zones, flowers, apical buds, and expanding leaves. A large number of genes associated with cell wall modifications are strongly up-regulated in root pieces colonized by SCN. However, in contrast to most of the transcripts for cell wall proteins, two XTH transcripts were specifically down-regulated in the colonized root pieces. Gene expression in serial dissections of root tips (0-2 mm, and 2-7 mm) and whole roots indicate that the SCN up-regulated genes are associated with a wide range of developmental processes in roots. Also of interest, many of the cDNAs examined were up-regulated in petiole abscission zones induced to abscise with ethylene.