Parabacteroides
Parabacteroides is a Gram-negative , anaerobic , non- spore -forming genus from the family Tannerellaceae . First isolated from fecal specimen in 1933, type strain Parabacteroides distasonis was originally classified under the name Bacteroides distasonis. The strain was re-classified to form the new genus Parabacteroides in 2006. Parabacteroides currently comprise 21 phylogenetically, ecologically, and metabolically diverse species, 11 of which are listed in the taxonomic database