A serological method for detection of Nosema ceranae.

AIMS: We developed a new method for detection of the intracellular parasite, Nosema ceranae, one of the most economically devastating pathogens of the honeybee. METHODS AND RESULTS: The SWP-32 antibody was used for the development of an enzyme-linked immunosorbent assay (ELISA). We also compared the efficiency of this ELISA to microscopy and quantitative real-time (qRT) PCR, the methods currently in use. CONCLUSIONS: ELISA is comparable in sensitivity with the qRT-PCR, less expensive and faster. When this method is commercialized and made available to bee-keepers, it will allow them to make informed decisions for the application of in-hive chemicals. Hence, bee-keepers may be able to determine when treatments for control of N. ceranae are unnecessary and reduce the cost, time and possible side effects of these treatments. SIGNIFICANCE AND IMPACT OF THE STUDY: This assay provides the first serological method for detection of N. ceranae in bee colonies, which is as sensitive as DNA amplification. It can be easily adopted for both laboratory and field applications.

Chalkbrood disease in honey bees.

Chalkbrood is a fungal disease of honey bee brood caused by Ascosphaera apis. This disease is now found throughout the world, and there are indications that chalkbrood incidence may be on the rise. In this review we consolidate both historic knowledge and recent scientific findings. We document the worldwide spread of the fungus, which is aided by increased global travel and the migratory nature of many beekeeping operations. We discuss the current taxonomic classification in light of the recent complete reworking of fungal systematics brought on by application of molecular methods. In addition, we discuss epidemiology and pathogenesis of the disease, as well as pathogen biology, morphology and reproduction. New attempts at disease control methods and management tactics are reviewed. We report on research tools developed for identification and monitoring, and also include recent findings on genomic and molecular studies not covered by previous reviews, including sequencing of the A. apis genome and identification of the mating type locus.

High mobility group (HMG-box) genes in the honeybee fungal pathogen Ascosphaera apis.

The genome of the honeybee fungal pathogen Ascosphaera apis (Maassen) encodes three putative high mobility group (HMG-box) transcription factors. The predicted proteins (MAT1-2, STE11 and HTF), each of which contain a single strongly conserved HMG-box, exhibit high similarity to mating type proteins and STE11-like transcription factors previously identified in other ascomycete fungi, some of them important plant and human pathogens. In this study we characterized the A. apis HMG-box containing genes and analyzed the structure of the mating type locus (MAT1-2) and its flanking regions. The MAT1-2 locus contains a single gene encoding a protein with an HMG-box. We also have determined the transcriptional patterns of all three HMG-box containing genes in both mating type idiomorphs and discuss a potential role of these transcription factors in A. apis development and reproduction. A multiplex PCR method with primers amplifying mat1-2-1 and Ste11 gene fragments is described. This new method allows for identification of a single mating type idiomorph and might become an essential tool for applied and basic research of chalkbrood disease in honeybees.

Genome sequences of the honey bee pathogens Paenibacillus larvae and Ascosphaera apis.

Genome sequences offer a broad view of host-pathogen interactions at the systems biology level. With the completion of the sequence of the honey bee, interest in the relevant pathogens is heightened. Here we report the genome sequences of two of the major pathogens of honey bees, the bacterium Paenibacillus larvae (causative agent for American foulbrood disease) and the fungus Ascosphaera apis. (causative agent for chalkbrood disease). Ongoing efforts to characterize the genomes of these species can be used to understand and mitigate the effects of two important pathogens, and will provide a contrast with pathogenic, benign and freeliving relatives.