Implementation of partial nitritation anammox (PNA) in the mainstream (municipal wastewater treatment) is still under investigation. Microbial community structure and reactor type can influence the performance of PNA reactor; yet, little is known about the role of the community composition of the inoculum and the reactor configuration under mainstream conditions. Therefore, this study investiga...

conclusions the results of the present study suggest that the presence of fusobacterium species in periodontal pockets is an important risk factor for halitosis. results in total, 26% (n = 13) and 8% (n = 4) samples were positive for fusobacterium species in the halitosis and control groups, respectively, with f. nucleatum present in the greatest proportion in both groups. halitophobia was sign...

Veterinary antibiotics in groundwater may affect natural microbial denitrification process. A microcosm study was conducted to evaluate the influence of sulfamethazine and chlortetracycline at different concentrations (0, 0.01, 0.1, and 1.0 mg/L) on nitrate reduction in groundwater under denitrifying condition. Decrease in nitrate removal and nitrite production was observed with the antibiotics...

Five strains of Gram-negative denitrifying bacteria that used various ketones as sole carbon and energy sources were isolated from activated sludge from a municipal sewage plant. Three strains are related to the genus Pseudomonas; two non-motile species have not yet been affiliated. All strains grew well with ketones and fatty acids (C2 to C7), but sugars were seldom utilized. The physiology of...

AIMS The bacterial diversity in a sequencing batch biofilm reactor (SBBR) treating landfill leachate was studied to explain the mechanism of nitrogen removal. METHODS AND RESULTS The total microbial DNA was extracted from samples collected from landfill leachate and biofilm of the reactor with the removal efficiencies of NH(4) (+)-N higher than 97% and that of chemical oxygen demand (determin...

A mutant of Brucella suis bearing a Tn5 insertion in norD, the last gene of the operon norEFCBQD, encoding nitric oxide reductase, was unable to survive under anaerobic denitrifying conditions. The norD strain exhibited attenuated multiplication within nitric oxide-producing murine macrophages and rapid elimination in mice, hence demonstrating that norD is essential for Brucella virulence.

Pseudomonas sp. strain T and Pseudomonas sp. strain K172 grow with toluene under denitrifying conditions. We demonstrated that anaerobic degradation of toluene was initiated by direct oxidation of the methyl group. Benzaldehyde and benzoate accumulated sequentially after toluene was added when cell suspensions were incubated at 5 degrees C. Strain T also grows anaerobically with m-xylene, and w...

The mbd cluster encodes the anaerobic degradation of 3-methylbenzoate in the β-proteobacterium Azoarcus sp. CIB. The specific transcriptional regulation circuit that controls the expression of the mbd genes was investigated. The PO, PB1, and P3R promoters responsible for the expression of the mbd genes, their cognate MbdR transcriptional repressor, as well as the MbdR operator regions (ATAC-N10...

Bacterial formation of carcinogenic N-nitroso compounds may play a role in the etiology of human cancer. Biochemical and immunological studies in denitrifying bacteria (Pseudomonas aeruginosa) strongly support the identification of cytochrome cd(1)-nitrite reductase as the enzyme responsible for the catalysis of nitrosation through the production of nitric oxide or NO(+)-like species. Interesti...

This study is focused on investigation of biofilms formed in an anaerobic laboratory-scale bioreactor fed with medium for anammox bacteria oxidizing ammonia with nitrite. The mixed culture of anammox bacteria was enriched from the microbial community that sampled from the activated sludge of a denitrifying reactor at a wastewater treatment station located in the Sochi region, Russia. This commu...