The novel strain TD-94 with higher ammonia degradation efficiency was isolated from the activated sludge of SINOPEC and belongs to the family of Alcaligenes faecalis (A. faecalis) based on its 16sRNA sequence and physio-biochemical characteristics. It is a Gram-negative, highly heterotrophic aerobic ammoxidation bacterium that is capable of effectively treating ammonia-nitrogen wastewater. The genome size of strain TD-94 was 4,361,949 bp with a GC content of 56.47% and a total of 4101 genes, which accounted for 89.54% of the total genome length. Analysis of various databases showed that 649 genes were annotated in the GO database; a total of 2712, 4095 and 12 genes were annotated in the KEGG, COG, and ADRB databases, respectively; and there were 24 types of cytochrome P450, 477 signal peptides, and eight secondary metabolites. All these data provide a theoretical basis for the mechanism of action of the strain TD-94. Based on the whole-genome sequencing results, functional genes related to nitrogen metabolism in A. faecalis TD-94, including aerobic ammonia oxidation (AOB), hydroxylamine oxidoreductase (HAO), and pyruvic oxime dioxygenase (POD) were identified. Through growth curve analysis and the identification of functional genes, the nitrogen metabolism pathway of A. faecalis TD-94 was proposed, demonstrating that the strain TD-94 has good denitrification capabilities and a novel degradative pathway.
Yang et al. (Fri,) studied this question.