Nitrous oxide as end product of denitrification by strains of fluorescent pseudomonads

Greenberg, E. P.; Becker, George E.

doi:10.1139/m77-133

Cited by 64 publications

(29 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In these, the correctness of the amplification products listed in boldface was confirmed by sequencing. As expected, no PCR product for nosZ was obtained in the cases of Escherichia coli K-12 and Pseudomonas chlororaphis (12).…”

Section: Methodssupporting

confidence: 76%

Biodiversity of Denitrifying and Dinitrogen-Fixing Bacteria in an Acid Forest Soil

Rösch

Mergel

Bothe

2002

Appl Environ Microbiol

493

302

View full text Add to dashboard Cite

Isolated soil DNA from an oak-hornbeam forest close to Cologne, Germany, was suitable for PCR amplification of gene segments coding for the 16S rRNA and nitrogenase reductase (NifH), nitrous oxide reductase (NosZ), cytochrome cd 1 -containing nitrite reductase (NirS), and Cu-containing nitrite reductase (NirK) of denitrification. For each gene segment, diverse PCR products were characterized by cloning and sequencing. None of the 16S rRNA gene sequences was identical to any deposited in the data banks, and therefore each of them belonged to a noncharacterized bacterium. In contrast, the analyzed clones of nifH gave only a few different sequences, which occurred many times, indicating a low level of species richness in the N 2 -fixing bacterial population in this soil. Identical nifH sequences were also detected in PCR amplification products of DNA of a soil approximately 600 km distant from the Cologne area. Whereas biodiversity was high in the case of nosZ, only a few different sequences were obtained with nirK. With respect to nirS, cloning and sequencing of the PCR products revealed that many false gene segments had been amplified with DNA from soil but not from cultured bacteria. With the 16S rRNA gene data, many sequences of uncultured bacteria belonging to the Acidobacterium phylum and actinomycetes showed up in the PCR products when isolated DNA was used as the template, whereas sequences obtained for nifH and for the denitrification genes were closely related to those of the proteobacteria. Although in such an experimental approach one has to cope with the enormous biodiversity in soils and only a few PCR products can be selected at random, the data suggest that denitrification and N 2 fixation are not genetic traits of most of the uncultured bacteria.

show abstract

Section: Methodssupporting

confidence: 76%

Biodiversity of Denitrifying and Dinitrogen-Fixing Bacteria in an Acid Forest Soil

Rösch

Mergel

Bothe

2002

Appl Environ Microbiol

493

302

View full text Add to dashboard Cite

show abstract

“…None of the strains tested produced N # upon the reduction of NO − # . Similar results have been observed for bacteria that reduce NO − # to N # O in previous studies (Bazylinski et al, 1986 ;Denariaz et al, 1989 ;Frunzke & Meyer, 1990 ;Greenberg & Becker, 1977 ;Kaspar, 1982 ;Shiba, 1991). Denitrifying bacteria that lack the capacity to reduce NO − $ have also been described previously (Finkmann et al, 2000 ;Grant & Payne, 1981 ;Rossau et al, 1987 et Yabuuchi et al, 1983), but the end products of denitrification for these bacteria have not been analysed comprehensively.…”

Section: Denitrification Reactionssupporting

confidence: 80%

Pseudoxanthomonas taiwanensis sp. nov., a novel thermophilic, N2O-producing species isolated from hot springs.

Chen¹,

Tsay²,

Chen³

et al. 2002

International Journal of Systematic and Evolutionary Microbiology

View full text Add to dashboard Cite

Two novel thermophilic bacterial strains, with an optimum growth temperature of between 50 and 60 mC, were isolated from the Chi-ban Hot Springs in eastern Taiwan. Strains CB-225 and CB-226 T were aerobic, thermophilic, non-sporulating, yellow-pigmented heterotrophic organisms. These strains exhibited an unusual denitrification reaction, reducing nitrite, but not nitrate, with the production of N 2 O only. On the basis of a phylogenetic analysis of 16S rDNA sequences, DNA-DNA similarity data, morphological, physiological and biochemical characteristics, and fatty acid compositions, it was found that the novel strains belonged to the genus Pseudoxanthomonas and represented a novel species within this genus, for which the name Pseudoxanthomonas taiwanensis is proposed ; the type strain is CB-226 T (l ATCC BAA-404 T l CCRC 17172 T ). P. taiwanensis differs from the only member of the genus Pseudoxanthomonas, the mesophilic species Pseudoxanthomonas broegbernensis, in that it exhibits a higher growth temperature and different morphological characteristics, such as the absence of polar flagella.

show abstract

“…The N 2 O reductase (EC 1.7.99.6) is a homodimeric multicopper enzyme, which has been purified from numerous gram-negative denitrifiers but not yet from a gram-positive bacterium (4,5,11,17,27). Production of N 2 O by denitrifying isolates as an end product of denitrification has been reported by several authors (2,3,7). Sequencing of the complete genome of Agrobacterium tumefaciens C58 revealed the presence of a denitrification cluster with genes encoding the periplasmic nitrate reductase, the copper nitrite reductase, and the nitric oxide reductase, but the genes encoding the N 2 O reductase were not found within the entire genome (30).…”

mentioning

confidence: 89%

Quantitative Detection of the nosZ Gene, Encoding Nitrous Oxide Reductase, and Comparison of the Abundances of 16S rRNA, narG , nirK , and nosZ Genes in Soils

Henry

Bru

Stres

et al. 2006

Appl Environ Microbiol

853

395

View full text Add to dashboard Cite

Nitrous oxide (N 2 O) is an important greenhouse gas in the troposphere controlling ozone concentration in the stratosphere through nitric oxide production. In order to quantify bacteria capable of N 2 O reduction, we developed a SYBR green quantitative real-time PCR assay targeting the nosZ gene encoding the catalytic subunit of the nitrous oxide reductase. Two independent sets of nosZ primers flanking the nosZ fragment previously used in diversity studies were designed and tested (K. Kloos, A. Mergel, C. Rösch, and H. Bothe, Aust. J. Plant Physiol. 28:991-998, 2001). The utility of these real-time PCR assays was demonstrated by quantifying the nosZ gene present in six different soils. Detection limits were between 10 1 and 10 2 target molecules per reaction for all assays. Sequence analysis of 128 cloned quantitative PCR products confirmed the specificity of the designed primers. The abundance of nosZ genes ranged from 10 5 to 10 7 target copies g ؊1 of dry soil, whereas genes for 16S rRNA were found at 10 8 to 10 9 target copies g ؊1 of dry soil. The abundance of narG and nirK genes was within the upper and lower limits of the 16S rRNA and nosZ gene copy numbers. The two sets of nosZ primers gave similar gene copy numbers for all tested soils. The maximum abundance of nosZ and nirK relative to 16S rRNA was 5 to 6%, confirming the low proportion of denitrifiers to total bacteria in soils.Nitrous oxide (N 2 O), with a global warming potential approximately 300 times higher than that of carbon dioxide, is an important greenhouse gas, contributing up to 6% of global warming. N 2 O also participates in depletion of the stratospheric ozone layer through stratospheric nitric oxide (NO) production. At present, the N 2 O concentration in the atmosphere is increasing at a rate of about 0.3% per year. The soil is the dominant source of atmospheric nitrous oxide, contributing about 57% (9 Tg year Ϫ1 ) of the total annual global emission (12). N 2 O emissions are highly variable in soils and are primarily produced by biological nitrification and denitrification, although the latter is considered to be the main source (31). N 2 O is an intermediate product in the denitrification pathway, which consists of the sequential reduction of NO 3 Ϫ to N 2 via the metalloenzymes nitrate reductase, nitrite reductase, nitric oxide reductase, and nitrous oxide reductase (32). Therefore, N 2 O emission by denitrification is the net result of the balance between production and reduction of N 2 O by denitrifying bacteria. The N 2 O reductase (EC 1.7.99.6) is a homodimeric multicopper enzyme, which has been purified from numerous gram-negative denitrifiers but not yet from a gram-positive bacterium (4,5,11,17,27). Production of N 2 O by denitrifying isolates as an end product of denitrification has been reported by several authors (2, 3, 7). Sequencing of the complete genome of Agrobacterium tumefaciens C58 revealed the presence of a denitrification cluster with genes encoding the periplasmic nitrate reductase, the copper nitrite reductase...

show abstract

Nitrous oxide as end product of denitrification by strains of fluorescent pseudomonads

Cited by 64 publications

References 7 publications

Biodiversity of Denitrifying and Dinitrogen-Fixing Bacteria in an Acid Forest Soil

Biodiversity of Denitrifying and Dinitrogen-Fixing Bacteria in an Acid Forest Soil

Pseudoxanthomonas taiwanensis sp. nov., a novel thermophilic, N2O-producing species isolated from hot springs.

Quantitative Detection of the nosZ Gene, Encoding Nitrous Oxide Reductase, and Comparison of the Abundances of 16S rRNA, narG , nirK , and nosZ Genes in Soils

Contact Info

Product

Resources

About