Paenibacillus larvae is a species of bacterium, found worldwide, which causes American foulbrood, a fatal disease of the larvae of honeybees (Apis mellifera). It is a Gram-positive, rod-shaped bacterium,[2] which forms spores which can remain viable for at least thirty-five years.[3]

Paenibacillus larvae
Scientific classification Edit this classification
Domain: Bacteria
Phylum: Bacillota
Class: Bacilli
Order: Bacillales
Family: Paenibacillaceae
Genus: Paenibacillus
Species:
P. larvae
Binomial name
Paenibacillus larvae
(White, 1906) Ash et al., 1994 emend. Heyndrickx et al., 1996 emend. Genersch et al., 2006
Synonyms[1]
  • Bacillus larvae White, 1906
  • Bacillus pulvifaciens Nakamura, 1984
  • Paenibacillus pulvifaciens (Nakamura, 1984) Ash et al., 1994
  • Paenibacillus larvae pulvifaciens (Nakamura, 1984) Heyndrickx et al., 1996
  • Paenibacillus larvae larvae (White, 1906) Ash et al., 1994 emend. Heyndrickx et al., 1996

Morphology

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P. larvae is a rod-shaped bacterium with slightly rounded ends, approximately 2.5–5 μm long and 0.5 μm wide.[4] The spore of P. larvae is oval, approximately 0.6 μm wide and 1.3 μm long.[4]

Classification

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In 1906, G.F. White first described the bacterium that caused American foulbrood (AFB), and named it Bacillus larvae.[5] In 1950, a bacterium isolated from bee larvae and associated with the rare disease "powdery scale" was named Bacillus pulvifaciens by Katznelson.[6] In 1993, both B. larvae and B. pulvifaciens were transferred to a new genus, Paenibacillus.[7] The two species were combined into a single species: Paenibacillus larvae in 1996, remaining differentiated as two subspecies: P. larvae ssp. larvae (formerly Bacillus larvae) and P. larvae ssp. pulvifaciens (formerly Bacillus pulvifaciens).[8] In 2006, the subspecies were eliminated based on spore morphology, biochemical profile and DNA testing, and when it was also demonstrated that experimental infection of honeybee larvae with the pulvifaciens subspecies caused American foulbrood signs without causing "powdery scale".[9]

There are at least four genotypes of P. larvae, named after their enterobacterial repetitive intergenic consensus (ERIC) sequences. Genotype ERIC I corresponds to the former species of Bacillus larvae, and genotypes ERIC II, III and IV correspond to the former species of B. pulvifaciens.[9] A fifth genotype ERIC V has recently been discovered in honey.[10]

Epidemiology

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P. larvae is found worldwide.[11][12] Genotypes ERIC I and II are most frequently isolated from global AFB outbreaks. In contrast, genotypes ERIC III and IV are found in bacteriology archives and are considered practically unimportant.[13] ERIC V was found in honey and has not been isolated from infected colonies yet.[10]

American foulbrood

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P. larvae causes American foulbrood in honeybees. The transmission is helped by small hive beetle, which the infected small hive beetle can spread the bacteria by directly contacting both honey and honeybee.[14]

References

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  1. ^ "Paenibacillus larvae". Integrated Taxonomic Information System. Retrieved 21 April 2020.
  2. ^ de Graaf, Dirk C; Alippi, Adriana M; Antúnez, Karina; Aronstein, Katherine A; Budge, Giles; De Koker, Dieter; De Smet, Lina; Dingman, Douglas W; Evans, Jay D; Foster, Leonard J; Fünfhaus, Anne; Garcia-Gonzalez, Eva; Gregore, Aleš; Human, Hannelie; Murray, K Daniel; Nguyen, Bach Kim; Poppinga, Lena; Spivak, Marla; van Engelsdorp, Dennis; Wilkins, Selwyn; Genersch, Elke (2 April 2015). "Standard methods for American foulbrood research". Journal of Apicultural Research. 52 (1): 1–28. doi:10.3896/IBRA.1.52.1.11. hdl:2263/40908.
  3. ^ Govan, VA; Allsopp, MH; Davison, S (May 1999). "A PCR detection method for rapid identification of Paenibacillus larvae". Applied and Environmental Microbiology. 65 (5): 2243–5. Bibcode:1999ApEnM..65.2243G. doi:10.1128/AEM.65.5.2243-2245.1999. PMC 91325. PMID 10224028.
  4. ^ a b Shimanuki, Hachiro; Knox, David A. (2000). "American foulbrood". Diagnosis of Honey Bee Diseases (PDF). Agriculture Handbook No. AH–690. U.S. Department of Agriculture. pp. 3–9. Retrieved 2020-02-26.
  5. ^ White, Gershom Franklin (1906). The bacteria of the apiary, with special reference to bee diseases. Technical series no. 14. Vol. no.14. Washington: U.S. Department of Agriculture, Bureau of Entomology. pp. 40–43. doi:10.5962/bhl.title.87503. {{cite book}}: |volume= has extra text (help)
  6. ^ Katznelson, H. (1950). "Bacillus Pulvifaciens (N. Sp.), an Organism Associated with Powdery Scale of Honeybee Larvae". Journal of Bacteriology. 59 (2): 153–155. doi:10.1128/jb.59.2.153-155.1950. ISSN 0021-9193. PMC 385736. PMID 15421942.
  7. ^ Ash, Carol; Priest, Fergus G.; Collins, M. David (1993). "Molecular identification of rRNA group 3 bacilli (Ash, Farrow, Wallbanks and Collins) using a PCR probe test: Proposal for the creation of a new genus Paenibacillus". Antonie van Leeuwenhoek. 64 (3–4): 253–260. doi:10.1007/BF00873085. ISSN 0003-6072. PMID 8085788. S2CID 7391845.
  8. ^ Heyndrickx, M.; Vandemeulebroecke, K.; Hoste, B.; Janssen, P.; Kersters, K.; De Vos, P.; Logan, N. A.; Ali, N.; Berkeley, R. C. W. (1996). "Reclassification of Paenibacillus (formerly Bacillus) pulvifaciens (Nakamura 1984) Ash et al. 1994, a Later Subjective Synonym of Paenibacillus (formerly Bacillus) larvae (White 1906) Ash et al. 1994, as a Subspecies of P. larvae, with Emended Descriptions of P. larvae as P. larvae subsp. larvae and P. larvae subsp. pulvifaciens". International Journal of Systematic Bacteriology. 46 (1): 270–279. doi:10.1099/00207713-46-1-270. ISSN 0020-7713. PMID 8573507.
  9. ^ a b Genersch, Elke; Forsgren, Eva; Pentikäinen, Jaana; Ashiralieva, Ainura; Rauch, Sandra; Kilwinski, Jochen; Fries, Ingemar (2006-03-01). "Reclassification of Paenibacillus larvae subsp. pulvifaciens and Paenibacillus larvae subsp. larvae as Paenibacillus larvae without subspecies differentiation". International Journal of Systematic and Evolutionary Microbiology. 56 (3): 501–511. doi:10.1099/ijs.0.63928-0. ISSN 1466-5026. PMID 16514018.
  10. ^ a b Beims, Hannes; Bunk, Boyke; Erler, Silvio; Mohr, Kathrin I.; Spröer, Cathrin; Pradella, Silke; Günther, Gabi; Rohde, Manfred; von der Ohe, Werner; Steinert, Michael (2020). "Discovery of Paenibacillus larvae ERIC V: Phenotypic and genomic comparison to genotypes ERIC I-IV reveal different inventories of virulence factors which correlate with epidemiological prevalences of American Foulbrood". International Journal of Medical Microbiology. 310 (2): 151394. doi:10.1016/j.ijmm.2020.151394. hdl:10033/622140. ISSN 1438-4221. PMID 31959580. S2CID 210841828.
  11. ^ Morrissey, Barbara J.; Helgason, Thorunn; Poppinga, Lena; Fünfhaus, Anne; Genersch, Elke; Budge, Giles E. (April 2015). "Biogeography of P aenibacillus larvae, the causative agent of American foulbrood, using a new multilocus sequence typing scheme". Environmental Microbiology. 17 (4): 1414–1424. Bibcode:2015EnvMi..17.1414M. doi:10.1111/1462-2920.12625. ISSN 1462-2912. PMC 4405054. PMID 25244044.
  12. ^ Papić, Bojan; Diricks, Margo; Kušar, Darja (2021-02-26). "Analysis of the Global Population Structure of Paenibacillus larvae and Outbreak Investigation of American Foulbrood Using a Stable wgMLST Scheme". Frontiers in Veterinary Science. 8: 582677. doi:10.3389/fvets.2021.582677. ISSN 2297-1769. PMC 7952629. PMID 33718463.
  13. ^ Genersch, Elke (January 2010). "American Foulbrood in honeybees and its causative agent, Paenibacillus larvae" (PDF). Journal of Invertebrate Pathology. 103: S10–S19. Bibcode:2010JInvP.103S..10G. doi:10.1016/j.jip.2009.06.015. PMID 19909971. Retrieved 2020-04-26.
  14. ^ Schäfer, Marc Oliver; Ritter, Wolfgang; Pettis, Jeff; Neumann, Peter (2010-01-01). "Small hive beetles, Aethina tumida, are vectors of Paenibacillus larvae". Apidologie. 41 (1): 14–20. doi:10.1051/apido/2009037. ISSN 1297-9678.