"Tropheryma whipplei" is a bacterium that is the causative organism of Whipple's disease,[1] and rarely, endocarditis.

"Tropheryma"
Scientific classification Edit this classification
Domain: Bacteria
Phylum: Actinomycetota
Class: Actinomycetia
Order: Micrococcales
Family: "Tropherymataceae"
Nouioui et al. 2018[2]
Genus:
"Tropheryma"

La Scola et al. 2001[1]
Species:
"T. whipplei"
Binomial name
"Tropheryma whipplei"
La Scola et al. 2001[1]
Synonyms[3]
  • Tropheryma whippelii Relman et al. 1992

While "T. whipplei" is categorized with the Gram-positive Actinomycetota, the organism is commonly found to be Gram-positive or Gram-indeterminate when stained in the laboratory.[1] Whipple himself probably observed the organisms as rod-shaped structures with silver stain in his original case.[4]

History of the name

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No name was given to the organism until 1991, when the name "Tropheryma whippelii" was proposed after sections of the bacterial genome were sequenced.[5][6] The name was changed to "Tropheryma whipplei" in 2001 (correcting the spelling of Whipple's name) when the organism was deposited in bacterial collections.[1]

As of 2008, the species, genus, and family name are considered to be invalid due to irregularities in the deposition of type material, and are thus styled in quotation marks.[7]

Pathogenesis

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Genome structure

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Several strains of "T. whipplei" have been sequenced.[8][9]

Genomes of intracellular or parasitic bacteria undergo massive reduction compared to their free-living relatives. With a genome size of less than 1 Mb, "T. whipplei" is a prime example of genome reduction among Actinomycetota. Other such examples include Mycoplasma for Bacillota (the low G+C content Gram-positive), Rickettsia for Alphaproteobacteria, and Wigglesworthia and Buchnera for Gammaproteobacteria.[8]

Some of the largest virions like Megavirus chilense, Pandoravirus, Pithovirus and Mimivirus are comparable in size to miniature bacteria like "T. whipplei" and Rickettsia conorii.

References

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  1. ^ a b c d e La Scola B, Fenollar F, Fournier PE, Altwegg M, Mallet MN, Raoult D (July 2001). "Description of Tropheryma whipplei gen. nov., sp. nov., the Whipple's disease bacillus". International Journal of Systematic and Evolutionary Microbiology. 51 (Pt 4): 1471–9. doi:10.1099/00207713-51-4-1471. PMID 11491348.
  2. ^ Nouioui, Imen; Carro, Lorena; García-López, Marina; Meier-Kolthoff, Jan P.; Woyke, Tanja; Kyrpides, Nikos C.; Pukall, Rüdiger; Klenk, Hans-Peter; Goodfellow, Michael; Göker, Markus (2018). "Genome-based taxonomic classification of the phylum Actinobacteria". Frontiers in Microbiology. 9 (2007): 1–119. doi:10.3389/fmicb.2018.02007. PMC 6113628. PMID 30186281.
  3. ^ Liang Z, La Scola B, Raoult D (January 2002). "Monoclonal antibodies to immunodominant epitope of Tropheryma whipplei". Clinical and Diagnostic Laboratory Immunology. 9 (1): 156–9. doi:10.1128/CDLI.9.1.156-159.2002. PMC 119894. PMID 11777846.
  4. ^ Whipple GH. (1907). "A hitherto undescribed disease characterized anatomically by deposits of fat and fatty acids in the intestinal and mesenteric lymphatic tissues". Johns Hopkins Hospital Bulletin. 18: 382–91.
  5. ^ Relman D, Schmidt T, MacDermott R, Falkow S (1992). "Identification of the uncultured bacillus of Whipple's disease". New England Journal of Medicine. 327 (5): 293–301. doi:10.1056/NEJM199207303270501. PMID 1377787.
  6. ^ From Greek τροφή trophê, "nourishment, food" and ἔρυμα eruma, "fence, a defence against, barrier".
  7. ^ "Species "Tropheryma whipplei"". LPSN - List of Prokaryotic names with Standing in Nomenclature.
  8. ^ a b Raoult D, et al. (2003). "Tropheryma whipplei Twist: a human pathogenic Actinobacteria with a reduced genome". Genome Res. 13 (8): 1800–9. doi:10.1101/gr.1474603. PMC 403771. PMID 12902375. Retrieved 8 August 2016.
  9. ^ Bentley, SD.; Maiwald, M.; Murphy, LD.; Pallen, MJ.; Yeats, CA.; Dover, LG.; Norbertczak, HT.; Besra, GS.; et al. (Feb 2003). "Sequencing and analysis of the genome of the Whipple's disease bacterium Tropheryma whipplei". Lancet. 361 (9358): 637–44. doi:10.1016/S0140-6736(03)12597-4. PMID 12606174. S2CID 8743326.