Corrections - Respiration-Dependent Proton Translocation and the Transport of Nitrate and Nitrite in Paracoccus dentrificans and Other Denitrifying Bacteria

Biochemistry ◽  
1979 ◽  
Vol 18 (19) ◽  
pp. 4262-4262
Author(s):  
Jakob Kristjansson ◽  
Bert Walter ◽  
Thomas Hollacher
Keyword(s):  
Proton Translocation ◽  
Denitrifying Bacteria ◽  
Nitrate And Nitrite

scholarly journals Functional characterisation of heterotrophic denitrifying bacteria in wastewater treatment systems

2005 ◽  
Author(s):  
◽  
Nishani Ramdhani
Keyword(s):  
Wastewater Treatment ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Denitrifying Bacteria ◽  
Culture Collection ◽  
Nitrite Reduction ◽  
Nitrogen And Phosphorus ◽  
Functional Characterisation ◽  
Gradient Gel Electrophoresis ◽  
Nitrate And Nitrite ◽  
Wastewater Treatment Systems

Atmospheric nitrogen pollution is on the increase and human activities are directly or indirectly responsible for the generation of the various nitrogen polluting compounds. This can lead to the two major problems of eutrophication and groundwater pollution. Therefore, the removal of nutrients such as nitrogen and phosphorus from wastewater is important. Nitrogen removal from wastewater is achieved by a combination of nitrification and denitrification. Thus, there is a need to identify and characterise heterotrophic denitrifying bacteria involved in denitrification in wastewater treatment systems. The aim of this study, therefore, was to characterise heterotrophic denitrifying bacteria through detailed biochemical and molecular analysis, to facilitate the understanding of their functional role in wastewater treatment systems. Drysdale (2001) isolated heterotrophic denitrifiers to obtain a culture collection of 179 isolates. This culture collection was used to screen for nitrate and nitrite reduction using the colorimetric biochemical nitrate reduction test. The isolates were thereafter Gram stained to assess their gram reaction, cellular and colonial morphology. Based on these results identical isolates were discarded and a culture collection of approximately 129 isolates remained. The genetic diversity of the culture collection was investigated by the analysis of polymerase chain reaction (PCR)-amplified 16S ribosomal DNA (rDNA) fragments on polyacrylamide gels using denaturing gradient gel electrophoresis (DGGE). Thus DNA fragments of the same length but different nucleotide sequences were effectively separated and microbial community profiles of eight predominant isolates were created. Batch experiments were conducted on these eight isolates, the results of which ultimately confirmed their characterisation and placed them into their four functional groups i.e. 3 isolates were incomplete denitrifiers, 2 isolates were true denitrifiers, 2 isolates were sequential denitrifiers and 1 isolate was an exclusive nitrite reducer.

scholarly journals Recording and Simulating Proton-Related Metabolism in Bacterial Cell Suspensions

2021 ◽  
Vol 12 ◽  
Author(s):  
Heribert Cypionka ◽  
Jan-Ole Reese
Keyword(s):  
Membrane Potential ◽  
Electron Transport ◽  
Proton Translocation ◽  
Model Organism ◽  
Desulfovibrio Desulfuricans ◽  
Cell Suspensions ◽  
Nitrite Reduction ◽  
Turnover Rates ◽  
Metabolic Activities ◽  
Nitrate And Nitrite

Proton release and uptake induced by metabolic activities were measured in non-buffered cell suspensions by means of a pH electrode. Recorded data were used for simulating substrate turnover rates by means of a new freeware app (proton.exe). The program applies Michaelis-Menten or first-order kinetics to the metabolic processes and allows for parametrization of simultaneously ongoing processes. The simulation includes changes of the transmembrane ΔpH, membrane potential and ATP gains, and demonstrates the principles of chemiosmotic energy conservation. In our experiments, the versatile sulfate-reducing bacterium Desulfovibrio desulfuricans CSN (DSM 9104) was used as model organism. We analysed sulfate uptake by proton-sulfate symport, scalar alkalinization by sulfate reduction to sulfide, as well as nitrate and nitrite reduction to ammonia, and electron transport-coupled proton translocation. Two types of experiments were performed: In oxidant pulse experiments, cells were kept under H2, and micromolar amounts of sulfate, nitrate or nitrite were added. For reductant pulse experiments, small amounts of H2-saturated KCl were added to cells incubated under N2 with an excess of one of the above-mentioned electron acceptors. To study electron-transport driven proton translocation, the membrane potential was neutralized by addition of KSCN (100 mM). H+/e– ratios of electron-transport driven proton translocation were calculated by simulation with proton.exe. This method gave lower but more realistic values than logarithmic extrapolation. We could verify the kinetic simulation parameters found with proton.exe using series of increasing additions of the reactants. Our approach allows for studying a broad variety of proton-related metabolic activities at micromolar concentrations and time scales of seconds to minutes.

DENITRIFICATION, DENITRIFYING BACTERIA, AND IRON REDUCTION IN A SOIL SUPPLEMENTED WITH SULFIDE AND ACETYLENE

1986 ◽  
Vol 66 (4) ◽  
pp. 633-639 ◽  
Author(s):  
ANNE M. ADKINS ◽  
ROGER KNOWLES
Keyword(s):  
Nitrous Oxide ◽  
Iron Reduction ◽  
Enrichment Culture ◽  
Denitrifying Bacteria ◽  
Sterile Soil ◽  
Culture Methods ◽  
Untreated Soil ◽  
Nitrous Oxide Reduction ◽  
Key Words Denitrification ◽  
Nitrate And Nitrite

Populations of denitrifying bacteria were estimated using MPN enrichment culture methods with nitrate, nitrite, and nitrous oxide (N2O) as electron acceptors. Nitrate and nitrite respirers predominated in untreated soil, and anaerobic preincubation with glucose and nitrate stimulated nitrate respirers 10-fold. During subsequent incubation with N2O and various combinations of acetylene (C2H2) and sulfide the numbers of nitrate and nitrite reducers decreased, and N2O reducers increased in treatments in which N2O reduction occurred. In the presence of N2O and C2H2 without sulfide there was no reduction of N2O and no change in the N2O-utilizing population. Incubation with N2O, C2H2, and sulfide caused a marked enrichment of N2O reducers in the denitrifying population. The addition of sulfide to anaerobic non-sterile or sterile soil caused an increase in reduced iron (Fe2+) and there was a relatively rapid conversion of free to acid-soluble sulfide. Key words: Denitrification, denitrifiers, sulfide, iron reduction, nitrous oxide reduction

scholarly journals Dynamics of nitrate and nitrite in saturated sand filters with enhanced substrate conditions for denitrifying bacteria

2021 ◽  
Vol 212 ◽  
pp. 51-60
Author(s):  
Rasha Al-Saedi ◽  
Keith Smettem ◽  
Katia Stefanova ◽  
Kadambot H.M. Siddique
Keyword(s):  
Denitrifying Bacteria ◽  
Saturated Sand ◽  
Sand Filters ◽  
Nitrate And Nitrite

The Reducing Action of Denitrifying Bacteria

1900 ◽  
Vol 50 (1303supp) ◽  
pp. 20889-20890
Author(s):  
G. Ampola ◽  
C. Ulpiani
Keyword(s):  
Denitrifying Bacteria
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