''Propionibacterium acnes'' type ''zappae'' is a

gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. Gram-positive bac ...

anaerobic Anaerobic means "living, active, occurring, or existing in the absence of free oxygen", as opposed to aerobic which means "living, active, or occurring only in the presence of oxygen." Anaerobic may also refer to: *Adhesive#Anaerobic, Anaerobic ad ...

, and

endophytic An endophyte is an endosymbiont, often a bacterium or fungus, that lives within a plant for at least part of its life cycle without causing apparent disease. Endophytes are ubiquitous and have been found in all species of plants studied to dat ...

bacterium species of ''

Propionibacterium ''Propionibacterium'' is a gram-positive, anaerobic, rod-shaped genus of bacteria named for their unique metabolism: They are able to synthesize propionic acid by using unusual transcarboxylase enzymes. Its members are primarily facultative pa ...

''. In 2014, it was found in an interkingdom bacterial transfer with grapevines (''

Vitis vinifera ''Vitis vinifera'', the common grape vine, is a species of flowering plant, native to the Mediterranean Basin, Mediterranean region, Central Europe, and southwestern Asia, from Morocco and Portugal north to southern Germany and east to northern ...

''), which is unexpected because ''P. acne'' is found on human skin. ''P. acnes zappae'' emerged about 7,000 years ago, roughly when the grapevine was domesticated. The bacterium colonizes the bark tissue and the

pith Pith, or medulla, is a tissue in the stems of vascular plants. Pith is composed of soft, spongy parenchyma cells, which in some cases can store starch. In eudicotyledons, pith is located in the center of the stem. In monocotyledons, it e ...

of the grapevine. ''P. zappae'' has endophytic characteristics which suggests that the bacterium has adapted to its new grapevine host as well as formed an endocellular symbiosis with the plant. ''P. acnes'' type ''zappae'' was named after the Italian term "zappa" '

hoe Hoe or HOE may refer to: * Hoe (food), a Korean dish of raw fish * Hoe (letter), a Georgian letter * Hoe (tool), a hand tool used in gardening and farming ** Hoe-farming, a term for primitive forms of agriculture * Backhoe, a piece of excavati ...

' and as a tribute to the musician

Frank Zappa Frank Vincent Zappa (December 21, 1940 – December 4, 1993) was an American musician, composer, and bandleader. His work is characterized by nonconformity, free-form improvisation, sound experiments, musical virtuosity and satire of A ...

who wrote about "sand-blasted zits". The unconventional behavior of this bacteria and its unique habitat caused scientists to think of Zappa and name the bacteria after him.

References

Propionibacteriales {{Propionibacterineae-stub