Enterococcaceae
The Enterococcaceae form a family of Gram-positive bacteria from the order of Lactobacillales. In this family, typical of lactic acid bacteria are present. Through the lactic acid fermentation bacteria form this group of sugars such as glucose, lactic acid (lactate ) and are extremely important for food production, such as in yogurt and cheese production. The term enterococci refers exclusively to the genus Enterococcus.
Features
The different types are not usually dependent on oxygen, facultative anaerobes. The cells are usually kokkenförmig, some how Atopobacter and the isolated termite genus Pilibacter, occur in the form of sticks. Coccoid cells can occur in pairs or chains. The majority of species do not have flagella and can not move actively (non- motile ).
Ecology
The species inhabit a variety of different habitats. Enterococcus is the water present in the soil, on plants and in the intestines of human and various animal species. Enterococcus faecalis and Enterococcus faecium are found in human mouth, intestines, vagina and urethra, and may have a pathogenic under certain circumstances. Types of Tetragenococcus, high salt concentrations ( halophiles ) tolerate. So Tetragenococcus halophilus was found in fermented fish dishes. The sooner the streptococci attributed type Melissococcus can pluton in honey bees cause the European foulbrood. The rod-shaped bacterium Atopobacter and the coccoid genus Catellicoccus of dead seals were isolated.
Although enterococci are part of healthy intestinal flora, they can cause infections in people with weakened immune systems. They are a common cause of nosocomial, typically occurring in hospitals, infections and can cause urinary infections, for example, or endocarditis.
Lactic acid fermentation and food production
With genres such as Enterococcus, Tetragenococcus and Vagococcus important lactic acid bacteria are represented within the Enterococcaceae. They have a homofermentative lactic acid fermentation type, in this case two molecules of adenosine triphosphate ( ATP) per molecule of glucose produced. The released end product is lactate. In contrast to heterofermentative lactic acid bacteria homofermentative lactic acid bacteria convert almost exclusively lactate free, while heterofermentative species, such as some species of Lactobacillus, in addition to lactic acid release, other end products, mostly ethanol and carbon dioxide ( CO2).
Lactic acid bacteria are the main persons involved in the production of milk production and other food fermentations organisms. Species such as Enterococcus faecium and Enterococcus faecalis, are important to the flavor development in cheese ripening and are also used in the production of probiotic foods. The genus Tetragenococcus, previously provided to Pediococcus, has a high salt tolerance ( is halophilic ) and plays an important role in the fermentation of some salted fish dishes. Tetragenococcus is further involved in the production of soy sauce, and pickle.
System
Genera of this family are:
- Bavariicoccus Schmidt et al. 2009
- Catellicoccus Lawson et al. 2006
- Enterococcus (ex Thiercelin & Jouhaud 1903) Schleifer & Kilpper - Bälz 1984
- Melissococcus Bailey & Collins 1983
- Pilibacter Higashiguchi et al. 2006
- Tetragenococcus Collins et al. 1993
- Vagococcus Collins et al. 1990