[Characteristics of the extracellular polymeric substances of a heterotrophic nitrifying bacterium strain].

To study the variation of extracellular polymers substances (EPS) composition of the heterotrophic denitrifying bacteria (Acinetobacter sp. YY-5) at different growth stages, The EPS of YY-5 was extracted by thermal, and the composition of protein, polysaccharides, nucleic acid and free amino acids were analyzed at different growth stages. Subsequently, the proteins in extracts were hydrolyzed into amino acids, the amino acid's changes and effect on physical and chemical properties of proteins were investigated.