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Melissococcus plutonius is the causative agent of European foulbrood (EFB), an important bacterial disease of honey bee larvae, and various methods have been developed for the detection of this dis...

In temperate climates, honey bee workers of the species Apis mellifera have different lifespans depending on the seasonal phenotype: summer bees (short lifespan) and winter bees (long lifespan). Many studies have revealed the biochemical parameters involved in the lifespan differentiation of summer and winter bees. However, comprehensive information regarding the metabolic changes occurring in their bodies between the two is limited. This study used proton nuclear magnetic resonance (1H NMR) spectroscopy to analyze the metabolic differences between summer and winter bees of the same age. The multivariate analysis showed that summer and winter bees could be distinguished based on their metabolic profiles. Among the 36 metabolites found, 28 metabolites have displayed significant changes from summer to winter bees. Compared to summer bees, trehalose in winter bees showed 1.9 times higher concentration, and all amino acids except for proline and alanine showed decreased patterns. We have also detected an unknown compound, with a CH3 singlet at 2.83 ppm, which is a potential biomarker that is about 13 times higher in summer bees. Our results show that the metabolites in summer and winter bees have distinctive characteristics; this information could provide new insights and support further studies on honey bee longevity and overwintering.

BACKGROUND Sodium channels (SCs) in mites and insects are target sites for pesticides, including pyrethroids. Point mutations in the SC gene have been reported to change the structural conformation of the protein and its sensitivity to pesticides. To find mutations in the SC gene of the mite Varroa destructor (VmNa), the authors analysed the VmNa gene sequences available in GenBank and prepared specific primers for the amplification of two fragments containing the regions coding for (i) the domain II S4–S6 region (bp 2805–3337) and (ii) the domain III S4-3′ terminus region (bp 4737–6500), as determined according to the VmNa cDNA sequence AY259834. RESULTS Sensitive and resistant mite populations did not differ in the amino acid sequences of the III S4-3′ terminus VmNa region. However, differences were found in the IIS4–IIS6 fragment. In the resistant population, the mutation C(3004) G resulted in the substitution L(1002) V (codon ctg gtg) at the position equivalent to that of the housefly L925 in the domain II S5 helix. Additionally, the mutation F(1052) L (codon ttc ctc) at the position equivalent to that of the housefly F975 in the domain II P-loop connecting segments S5 and S6 was detected in both the resistant and sensitive populations. CONCLUSION All individuals that survived the tau-fluvalinate treatment in the bioassay harboured the L(1002) V mutation combined with the F(1052), while dead individuals from both the sensitive and resistant populations harboured mostly the L(1002) residue and either of the two residues at position 1052. © 2013 Society of Chemical Industry

International audience; AbstractThe honeybee, Apis mellifera, undergoes complete metamorphosis before transitioning to the adult stage. The newly emerged individual and the red-eye pupa stage are well defined and easily recognizable in the time life cycle honeybee and, therefore, very useful for studying physiological and developmental factors. We analyzed in detail the hemolymph proteome of newly emerged honeybee worker using 2D-E-MS/MS (pI 3-10 and 4-7). The comparison of identical hemolymph volumes (20 μL per 2D-E) for newly emerged bee and red-eye pupa revealed a dramatic decrease in the number of spots (qualitative changes) and overall protein quantity during the non-feeding stage. The results increase our knowledge about honeybee metamorphosis during the non-feeding period and clarify previous findings regarding particular proteins. The results will be useful for future comparative physiological, developmental, and host-pathogen studies on individual or population level.

Department of Pest Control of Stored Products and Food Safety, Laboratory of Proteomics, Crop Research Institute, Drnovska 507/73, Prague 6-Ruzyne CZ16106, Czech Republic Department of Parasitology, Faculty of Science, Charles University in Prague, Prague, Czech Republic Laboratory of Mass Spectrometry, Faculty of Science, Charles University in Prague, Prague, Czech Republic Department of Cell Biology, Faculty of Science, Charles University in Prague, Prague, Czech Republic Bee Research Institute at Dol, Libcice nad Vltavou, Czech Republic

International audience; Apis mellifera Linnaeus is a holometabolous insect that undergoes complete metamorphosis in its nonfeeding pupal stage before transitioning to the adult stage. Its pupal stages are classifiable by the unique color pigmentation of its compound eyes and thorax; notably, there is a red-eye stage involving an unpigmented body that has a relatively short duration and is easy to recognize. The aim of the current study was to create a proteomic reference map of the worker red-eye pupa hemolymph. Hemolymph was collected from dorsal vessels using glass capillary tubes and was examined using pI 3–10 two-dimensional gel electrophoresis (2DE; 10 and 14 %) and matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF)/TOF protein identification. This experimental approach allowed us to identify 129 different proteins organized into orthologous groups. Overall, the predominant category was post-translational modifications, protein turnover and chaperones (23.3 % of the identified proteins). In addition, we identified proteins in the non-orthologous groups of olfaction (2.3 % of the identified proteins) and storage hexamerins (3.1 % of the identified proteins). Quantitatively, the major protein isoforms that were accurately identified via 10 % 2DE were four forms of storage hexamerin: the 110, 70a, 70b, and 70c forms. The most abundant enzymes identified were short-chain dehydrogenases/reductases with pivotal developmental roles in ecdysteroidogenesis and a sigma class glutathione-S-transferase that most likely serves as a major protectant against the by-products of oxidative stress. Many of the identified proteins are known to be involved in the mechanisms of metamorphosis. All of the identified proteins are useful as markers for future comparative physiological and developmental studies.

International audience; Honeybee (Apis mellifera Linnaeus) colonies in temperate zones produce either summer bees, which have a lifespan of 15 to 48 days, or winter bees, which emerge in late summer and live up to 8 months. Winter bees develop unique physiological conditions characterized by changes in protein composition that appear to be major determinants of honeybee lifespan. We analyzed winter honeybee worker hemolymph using a proteomic approach for the first time. Hemolymph collected from the dorsal vessel of winter honeybees using a glass capillary tube was analyzed using two-dimensional gel electrophoresis followed by MALDI TOF/TOF protein identification. Overall, 93 spots were assigned significance (P

American foulbrood, because of its virulence and worldwide spread, is currently one of the most dangerous diseases of honey bees. Quick diagnosis of this disease is therefore vitally important. For its successful eradication, however, all the hives in the region must be tested. This is time consuming and costly. Therefore, a fast and sensitive method of detecting American foulbrood is needed. Here we present a method that significantly reduces the number of tests needed by combining batches of samples from different hives. The results of this method were verified by testing each sample. A simulation study was used to compare the efficiency of the new method with testing all the samples and to develop a decision tool for determining when best to use the new method. The method is suitable for testing large numbers of samples (over 100) when the incidence of the disease is low (10% or less).