Gemella
Gemella is a genus of bacteria.
Features
The types of Gemella are gram positive. The cells are ovoid, the individual cells are arranged in pairs, tetrads and in grape-like clusters of cells. Rarely, even short chains. Also, rod-shaped cells may occur.
The genus Gemella is a facultative anaerobe and shows best growth rates under high CO2 content. The oxidase test and catalase test is negative. Gemella used as the fermentation pathway. Haemolysans G. and G. morbillorum ferment under anaerobic glucose to acetic acid and lactic acid.
Gemella Gemella haemolysans and morbillorum inhabit mucous membranes of humans and other mammals. Gemella haemolysans was in the oral cavity and upper digestive tract found by healthy people. However, Gemella haemolysans can also act pathogenic and cause endocarditis. Can morbillorum Gemella sepsis, abscesses and wound infections and infections in the urogenital cause.
System
The genus Gemella was originally provided to the family Neisseriaceae, but further investigation showed too many inconsistencies with the features of this family. In 1974, she was ranked in the Staphylococcaceae family, but the family was not accepted on that date within the meaning of the bacterial systematics. It was shown later that Gemella because of several characteristics of other genres so different that the assignment to a joint family in 2009 no longer seemed justifiable. The reasons for this are, in particular, the negative catalase and oxidase test, and the composition of the lipids in the cell membrane. 2013, it is not assigned to a family, but only made to order Bacillales.
The following species are known (as of 2013):
- Gemella asaccharolytica Ulger Toprak et al. 2010
- Gemella bergeri Corrig. Collins et al. 1998
- Gemella cuniculi Hoyles et al. 2000
- Gemella haemolysans ( Thjøtta and Bøe 1938) Berger, 1960 ( the type species of the genus )
- Gemella morbillorum ( Prévot 1933) Kilpper - Balz and Schleifer 1988
- Gemella palaticanis Collins et al. 1999
- Gemella sanguinis Collins et al. 1999