"Tropheryma whipplei" is a bacterium that is the causative organism of Whipple's disease,^[2] and rarely, endocarditis.

Quick Facts "Tropheryma", Scientific classification ...

"Tropheryma"
Scientific classification
Domain:	Bacteria
Phylum:	Actinomycetota
Class:	Actinomycetia
Order:	Micrococcales
Family:	"Tropherymataceae" Nouioui et al. 2018[1]
Genus:	"Tropheryma" La Scola et al. 2001[2]
Species:	"T. whipplei"
Binomial name
"Tropheryma whipplei" La Scola et al. 2001[2]
Synonyms[3]
Tropheryma whippelii Relman et al. 1992

Close

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.^[2] Whipple himself probably observed the organisms as rod-shaped structures with silver stain in his original case.^[4]

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.^[2]

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]

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 chilensis, Pandoravirus, Pithovirus and mimivirus are comparable in size to miniature bacteria like "T. whipplei" and Rickettsia conorii.