The characterization and description of representatives of 'G' bacteria from activated sludge plants

Abstract

The name Tetracoccus cechii is proposed for two strains of the tetrad arranged cocci, previously known as 'G' bacteria, which were isolated from laboratory scale activated sludge plants in the Czech Republic and in Italy. They were morphologically, phenotypically and phylogenetically characterized and found to comprise a novel lineage in the alpha-3 group of the proteobacterial phylum in the domain Bacteria. The strains are Gram-negative and produce intracellular inclusions of poly-β-hydroxybutyrate. Although commonly seen in activated sludge mixed liquor as cocci 1-2 μm in diameter, arranged in tetrads, in pure culture they can also grow in amorphous aggregations and the cells are generally..