Bifidobacterium
Bifidobacterium adolescentis stained by Gram's method, light microscopy
The bifidobacteria, identical to the bacterial genus Bifidobacterium (from Latin bifidus, " split, forked " ), belonging to the family Bifidobacteriaceae, are gram-positive, not actively moving, not forming spores, predominantly anaerobic rods, often club-shaped ( " coryneform "). They form on agar gel culture media smooth microcolonies without filaments. Its members have similarity with corynebacteria.
For the normal bacterial community of the gastrointestinal tract, appendix and vagina include, inter alia, B. bifidum, B. adolescentis, B. breve, B. longum and B. infantis. They are non-pathogenic, i.e., they are harmless to humans.
Metabolism
Bifidobacteria have no glucose -6-phosphate dehydrogenase and glucose build its own complicated Energiestoffwechselweg (English " Bifidum Pathway " ) from. The path leads over phosphoric esters of hexoses, erythrose, glyceraldehyde and pentoses, with acetyl phosphate is cleaved at two sites next to glyceraldehyde -3-phosphate is formed. This is degraded via the Embden - Meyerhof pathway to lactic acid. The phosphate group of the acetyl phosphate is transferred to adenosine diphosphate (ADP ) to form adenosine triphosphate ( ATP). The sugars are broken down to acetic acid and lactic acid in the ratio 3:2. This pathway results in a 25% higher yield of ATP (2.5 mol per mol glucose ) and the homofermentative lactic acid fermentation (2 moles per mole of glucose).
Net reaction: 1 glucose 2.5 2.5 ADP phosphate → 1 lactate acetate 1.5 2.5 ATP
System
A selection of Types:
- Bifidobacterium adolescentis Reuter 1963
- Bifidobacterium animalis subsp. lactis ( mile et al. 1997) Masco et al. 2004
- Bifidobacterium bifidum ( Tissier 1900) Orla -Jensen 1924 ( type species )
- Bifidobacterium breve Reuter 1963
- Bifidobacterium infantis Reuter 1963
- Bifidobacterium longum Reuter 1963