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1.
Removal of methanethiol, dimethyl sulfide, dimethyl disulfide, and hydrogen sulfide from contaminated air by Thiobacillus thioparus TK-m. 总被引:4,自引:2,他引:2
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Methanethiol, dimethyl sulfide, dimethyl disulfide, and hydrogen sulfide were efficiently removed from contaminated air by Thiobacillus thioparus TK-m and oxidized to sulfate stoichiometrically. More than 99.99% of dimethyl sulfide was removed when the load was less than 4.0 g of dimethyl sulfide per g (dry cell weight) per day. 相似文献
2.
Summary A new Basidiomycete showed significantly higher degradation rates, 10,000 times for H2S,40 times for dimethyl sulfide(DMS),15 times for methanethiol(MT) and 4 times for dimethyl disulfide(DMDS) than any reported previously. The optimal pH for degradation activity was around 7. Degradation rate for each gas when mixed gases of H2S,MT and DMS were supplied was almost the same as that for single gas supply. H2S was oxidized to SO4 via SO3 and DMS was stoichiometrically converted to dimethyl sulfoxide(DMSO). 相似文献
3.
《Journal of Fermentation and Bioengineering》1989,67(4):280-285
Cells of Thiobacillus thioparus TK-m were immobilized on cylindrical porous polypropylene pellets (5 mmφ × 5 mm) which were packed in an acrylic cylinder of 50 mm inner diameter up to the height of 800 mm. When a sulfur-containing malodorous gas was charged to this packed tower at the superficial velocity of 0.1 m/s, maximum loading capacity (mmol/l·d) for a malodorous gas to attain the removal rate of 95% or more was: 3.65 for dimethyl sulfide, 8.74 for methyl mercaptan, and 17.36 for hydrogen sulfide. At this time, the inlet concentration (μl/l) of the malodorous compound was: 7.44 for dimethyl sulfide, 17.8 for methyl mercaptan, and 35.4 for hydrogen sulfide. For every compound, higher loading resulted in greater removal quantities. The removal rate of dimethyl sulfide was not overly affected by the presence of a large amount of easily decomposable hydrogen sulfide. 相似文献
4.
Dimethyl sulfide dehydrogenase from the purple phototrophic bacterium Rhodovulum sulfidophilum catalyzes the oxidation of dimethyl sulfide to dimethyl sulfoxide. Recent DNA sequence analysis of the ddh operon, encoding dimethyl sulfide dehydrogenase (ddhABC), and biochemical analysis (1) have revealed that it is a member of the DMSO reductase family of molybdenum enzymes and is closely related to respiratory nitrate reductase (NarGHI). Variable temperature X-band EPR spectra (120-122 K) of purified heterotrimeric dimethyl sulfide dehydrogenase showed resonances arising from multiple redox centers, Mo(V), [3Fe-4S](+), [4Fe-4S](+), and a b-type heme. A pH-dependent EPR study of the Mo(V) center in (1)H(2)O and (2)H(2)O revealed the presence of three Mo(V) species in equilibrium, Mo(V)-OH(2), Mo(V)-anion, and Mo(V)-OH. Above pH 8.2 the dominant species was Mo(V)-OH. The maximum specific activity occurred at pH 9.27. Comparison of the rhombicity and anisotropy parameters for the Mo(V) species in DMS dehydrogenase with other molybdenum enzymes of the DMSO reductase family showed that it was most similar to the low-pH nitrite spectrum of Escherichia coli nitrate reductase (NarGHI), consistent with previous sequence analysis of DdhA and NarG. A sequence comparison of DdhB and NarH has predicted the presence of four [Fe-S] clusters in DdhB. A [3Fe-4S](+) cluster was identified in dimethyl sulfide dehydrogenase whose properties resembled those of center 2 of NarH. A [4Fe-4S](+) cluster was also identified with unusual spin Hamiltonian parameters, suggesting that one of the iron atoms may have a fifth non-sulfur ligand. The g matrix for this cluster is very similar to that found for the minor conformation of center 1 in NarH [Guigliarelli, B., Asso, M., More, C., Augher, V., Blasco, F., Pommier, J., Giodano, G., and Bertrand, P. (1992) Eur. J. Biochem. 307, 63-68]. Analysis of a ddhC mutant showed that this gene encodes the b-type cytochrome in dimethyl sulfide dehydrogenase. Magnetic circular dichroism studies revealed that the axial ligands to the iron in this cytochrome are a histidine and methionine, consistent with predictions from protein sequence analysis. Redox potentiometry showed that the b-type cytochrome has a high midpoint redox potential (E degrees = +315 mV, pH 8). 相似文献
5.
Masae Horinouchi Kano Kasuga Hideaki Nojiri Hisakazu Yamane Toshio Omori 《FEMS microbiology letters》1997,155(1):99-105
Acinetobacter sp. strain 20B was isolated based on the ability to utilize dimethyl sulfide as the sole sulfur source. Since strain 20B oxidized indole as well as dimethyl sulfide, indigo production by recombinant Escherichia coli clones carrying Acinetobacter DNA was used as a selection for cloning genes encoding dimethyl sulfide oxidation genes. The gene encoding an indole-oxidizing enzyme was also found to oxidize dimethyl sulfide. The dimethyl sulfide-oxidizing enzyme genes consisted of six open reading flames designated dsoABCDEF. The deduced amino acid sequences of dsoABCDEF were homologous with those of the multicomponent phenol hydroxylases. DsoABCDEF oxidized dimethyl sulfide to dimethyl sulfoxide, and dimethyl sulfoxide to dimethyl sulfone. 相似文献
6.
Abstract: The purple sulfur bacterium Thiocapsa roseopersicina was examined for photo-autotrophic growth on dimethyl sulfide (DMS). The maximum specific growth rate μ max (0.068 h−1 ), saturation constant K s (38 μm l−1 ), and yield (5.24 mg protein mmol−1 DMS) were determined in chemostat experiments. Dimethyl sulfoxide was the only product of DMS oxidation. Batch experiments revealed the simultaneous oxidation of DMS and hydrogen sulfide. 相似文献
7.
《Process Biochemistry》2007,42(10):1398-1405
Inappropriate biological treatment of dimethyl sulfoxide (DMSO) used by opto-electronics and semi-conductor industries would result in production of malodorous compounds, e.g. dimethyl sulfide, methane-thiol and hydrogen sulfide. The best sludge for DMSO biodegradation was obtained from the activated sludge of a chemical company that used to provide DMSO for the above industries. Under the optimal conditions of pH 7.0–8.5 and 30 °C, the highest removal efficiency in treatment of 500 mg l−1 of DMSO occurred at the rate of 0.078 g DMSO per gram suspended solids per day corresponding to 37 h for complete DMSO biodegradation in a shake-flask culture. However, the time needed for DMSO biodegradation could be reduced to 16 h at the rate of 0.153 g DMSO per gram suspended solids per day if a repeated-batch mode was adopted, indicating that an acclimation period is required by the DMSO degraders. The reaction time could further be shortened to less than 10 h with 95% removal of the 750 mg l−1 DMSO at the maximum rate of 0.909 g DMSO per gram suspended solids per day using an oxygen-enriched air-lift bioreactor. No malodorous compounds, such as dimethyl sulfide, were produced revealing that the biodegradation pathway is oxidative and can solve the odor problems common in the biological wastewater treatment plant of the abovementioned industries. 相似文献
8.
C. Vogt Andreas Rabenstein Jörg Rethmeier Ulrich Fischer 《Archives of microbiology》1998,169(3):263-266
By the method of cold alkali hydrolysis, 29 marine benthic cyanobacteria were screened for production of alkali-labile precursors
of dimethyl sulfide (DMS) including dimethylsulfoniopropionate (DMSP), a compound of significant importance in marine environments.
Concentrations of DMS precursors ranged from undetectable to 0.8 mmol (g Chl a)–1. The data correspond to some previous investigations concerning DMSP content of marine cyanobacteria and suggest that marine
benthic cyanobacteria are only minor producers of DMSP.
Received: 3 July 1997 / Accepted: 21 October 1997 相似文献
9.
Anaerobic degradation of methylmercaptan and dimethyl sulfide by newly isolated thermophilic sulfate-reducing bacteria. 总被引:5,自引:4,他引:1
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The complete oxidation of methylmercaptan (MSH) and dimethyl sulfide (DMS) with sulfate or nitrate as electron acceptors was observed in enrichment cultures and dilution series using thermophilic fermentor sludge as the inoculum. Three new strains of thermophilic sulfate reducers were isolated in pure culture (strains MTS5, TDS2, and SDN4). Strain MTS5 grew on MSH and strain TDS2 grew on DMS whereas strain SDN4 grew on either MSH or DMS. The cellular growth yields were 2.57 g (dry weight)/mol of MSH for strain MTS5 and 6.02 g (dry weight)/mol of DMS for strain TDS2. All strains used sulfate, sulfite, or thiosulfate as electron acceptors, but only strain SDN4 used nitrate. DMS and MSH were oxidized to CO2 and sulfide with either sulfate or nitrate as the electron acceptor. Sulfate was stoichiometrically reduced to sulfide while nitrate was reduced to ammonium. All strains were motile rods, required biotin for growth, lacked desulfoviridin, had DNA with G+C contents of 48 to 57 mol% and probably belonged to the genus Desulfotomaculum. This is the first report of the oxidation of MSH and DMS by pure cultures of sulfate-reducing bacteria. 相似文献
10.
Operational and microbiological aspects of a bioaugmented two-stage biotrickling filter removing hydrogen sulfide and dimethyl sulfide 总被引:15,自引:0,他引:15
Sercu B Núñez D Van Langenhove H Aroca G Verstraete W 《Biotechnology and bioengineering》2005,90(2):259-269
A two-stage biotrickling filter was developed for removing dimethyl sulfide (DMS) and hydrogen sulfide (H2S). The first biotrickling filter (ABF) was inoculated with Acidithiobacillus thiooxidans and operated without pH control, while the second biotrickling filter (HBF) was inoculated with Hyphomicrobium VS and operated at neutral pH. High DMS elimination capacities were observed in the HBF (8.2 g DMS m(-3) h(-1) at 90% removal efficiency) after 2 days. Maximal observed elimination capacities were 83 g H2S m(-3) h(-1) (100% removal efficiency) and 58 g DMS m(-3) h(-1) (88% removal efficiency) for the ABF and the HBF, respectively. The influence of a decreasing empty bed residence time (120 down to 30 sec) and the robustness of the HBF towards changing operational parameters (low pH, starvation, and DMS and H2S peak loadings) were investigated. Suboptimal operational conditions rapidly resulted in lower DMS removal efficiencies, but recovery of the HBF was mostly obtained within a few days. The H2S removal efficiency in the ABF, however, was not influenced by varying operational conditions. In both reactors, microbial community dynamics of the biofilm and the suspended bacteria were investigated, using denaturing gradient gel electrophoresis (DGGE). After a period of gradual change, a stable microbial community was observed in the HBF after 60 days, although Hyphomicrobium VS was not the dominant microorganism. In contrast, the ABF biofilm community was stable from the first day and only a limited bacterial diversity was observed. The planktonic microbial community in the HBF was very different from that in the biofilm. 相似文献
11.
Albert Tangerman 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2009,877(28):3366-3377
This review deals with the measurement of the volatile sulfur compounds hydrogen sulfide, methanethiol and dimethyl sulfide in various biological matrices of rats and humans (blood, serum, tissues, urine, breath, feces and flatus). Hydrogen sulfide and methanethiol both contain the active thiol (–SH) group and appear in the free gaseous form, in the acid-labile form and in the dithiothreitol-labile form. Dimethyl sulfide is a neutral molecule and exists only in the free form. The foul odor of these sulfur volatiles is a striking characteristic and plays a major role in bad breath, feces and flatus. Because sulfur is a biologically active element, the biological significance of the sulfur volatiles are also highlighted. Despite its highly toxic properties, hydrogen sulfide has been lately recommended to become the third gasotransmitter, next to nitric oxide and carbon monoxide, based on high concentration found in healthy tissues, such as blood and brain. However, there is much doubt about the reliability of the assay methods used. Many artifacts in the sulfide assays exist. The methods to detect the various forms of hydrogen sulfide are critically reviewed and compared with findings of our group. Recent findings that free gaseous hydrogen sulfide is absent in whole blood urged the need to revisit its role as a blood-borne signaling molecule. 相似文献
12.
Inhibition of microbiological sulfide oxidation by methanethiol and dimethyl polysulfides at natron-alkaline conditions 总被引:1,自引:0,他引:1
Pim L. F. van den Bosch Marco de Graaff Marc Fortuny-Picornell Robin C. van Leerdam Albert J. H. Janssen 《Applied microbiology and biotechnology》2009,83(3):579-587
To avoid problems related to the discharge of sulfidic spent caustics, a biotechnological process is developed for the treatment
of gases containing both hydrogen sulfide and methanethiol. The process operates at natron-alkaline conditions (>1 mol L−1 of sodium- and potassium carbonates and a pH of 8.5–10) to enable the treatment of gases with a high partial CO2 pressure. In the process, methanethiol reacts with biologically produced sulfur particles to form a complex mixture predominantly
consisting of inorganic polysulfides, dimethyl disulfide (DMDS), and dimethyl trisulfide (DMTS). The effect of these organic
sulfur compounds on the biological oxidation of sulfide to elemental sulfur was studied with natron-alkaliphilic bacteria
belonging to the genus Thioalkalivibrio. Biological oxidation rates were reduced by 50% at 0.05 mM methanethiol, while for DMDS and DMTS, this was estimated to occur
at 1.5 and 1.0 mM, respectively. The inhibiting effect of methanethiol on biological sulfide oxidation diminished due to its
reaction with biologically produced sulfur particles. This reaction increases the feasibility of biotechnological treatment
of gases containing both hydrogen sulfide and methanethiol at natron-alkaline conditions. 相似文献
13.
Aerobic degradation of dimethyl sulfide (DMS), previously described for thiobacilli and hyphomicrobia, involves catabolism to sulfide via methanethiol (CH3SH). Methyl groups are sequentially eliminated as HCHO by incorporation of O2 catalyzed by DMS monooxygenase and methanethiol oxidase. H2O2 formed during CH3SH oxidation is destroyed by catalase. We recently isolated Thiobacillus strain ASN-1, which grows either aerobically or anaerobically with denitrification on DMS. Comparative experiments with Thiobacillus thioparus T5, which grows only aerobically on DMS, indicate a novel mechanism for aerobic DMS catabolism by Thiobacillus strain ASN-1. Evidence that both organisms initially attacked the methyl group, rather than the sulfur atom, in DMS was their conversion of ethyl methyl sulfide to ethanethiol. HCHO transiently accumulated during the aerobic use of DMS by T. thioparus but not with Thiobacillus strain ASN-1. Catalase levels in cells grown aerobically on DMS were about 100-fold lower in Thiobacillus strain ASN-1 than in T. thioparus T5, suggesting the absence of H2O2 formation during DMS catabolism. Also, aerobic growth of T. thioparus T5 on DMS was blocked by the catalase inhibitor 3-amino-1,2,4-triazole whereas that of Thiobacillus strain ASN-1 was not. Methyl butyl ether, but not CHCl3, blocked DMS catabolism by T. thioparus T5, presumably by inhibiting DMS monooxygenase and perhaps methanethiol oxidase. In contrast, DMS metabolism by Thiobacillus strain ASN-1 was unaffected by methyl butyl ether but inhibited by CHCl3. DMS catabolism by Thiobacillus strain ASN-1 probably involves methyl transfer to a cobalamin carrier and subsequent oxidation as folate-bound intermediates. 相似文献
14.
Maeda I Yamashiro H Yoshioka D Onodera M Ueda S Kawase M Miyasaka H Yagi K 《Applied microbiology and biotechnology》2006,70(4):397-402
A colorimetric whole-cell sensor for dimethyl sulfide (DMS) was constructed based on the in vivo conversion of intrinsic pigments
in response to the analyte. In a marine bacterium, Rhodovulum sulfidophilum, carotenoids are synthesized via the spheroidene pathway. In this pathway, demethylspheroidene, a yellow carotenoid, is converted
to spheroidene under catalysis of O-methyltransferase. Spheroidene monooxygenase (CrtA) catalyzes the terminal step of the pathway and converts spheroidene to
spheroidenone, a red carotenoid. Here, the CrtA gene in R. sulfidophilum was removed and then reintroduced downstream of the DMS dehydrogenase gene promoter. Using this whole-cell sensor, 3 μM DMS
or dimethyl sulfoxide can be detected without adding any color-forming reagent. The ratio of the red spheroidenone to total
carotenoids increased, as the DMS concentration was raised to 0.3 mM. Comparison of the signal to the background color indicated
a shift in the color coordinate from a yellow to a red hue. An intense signal was obtained with 1-day incubation at a high
cell density when sensor cells at the exponential growth phase were used. These results show that the genetically engineered
R. sulfidophilum cells can be used to monitor the quality of marine aquacultural environments by the naked eye. 相似文献
15.
Production of methyl sulfide and dimethyl disulfide from soil-incorporated plant materials and implications for controlling soilborne pathogens 总被引:1,自引:0,他引:1
Soil-incorporated plant materials have been associated with reduction in soilborne pathogens and diseases. Mechanisms of the biocidal actions are complex and not well understood. A glasshouse experiment, a non replicated field demonstration, and a field experiment were conducted to determine volatile compounds after incorporation of various plant species and their effect on pest control. Cabbage (Brassica oleracea), canola (Brassica rapa), kale (Brassica oleracea var. acephala), lettuce (Lactuca sativa var. valmaine), two mustard varieties -Caliente (Brassica juncea) and Green wave (Brassica juncea), two radish varieties - Oil seed (Raphanus sativus var. oleiformis) and Cherriette (Raphanus sativus), common rye (Secale cereale), and sorghum Sudan grass (Sorghum bicolor var. sudanese) were used in the glasshouse experiment. Caliente 199 mustard (Brassica hirta) was planted in the field demonstration and white mustard (Sinapis alba) was used in the field experiment. Fresh plant materials were chopped manually in the glasshouse experiment and mechanically in the field studies at the flowering stage before incorporation in natural field soils. In the glasshouse experiment, the equivalent biomass dry weight ranged from a minimum of 573 g?m?2 for L. sativa var. valmaine to a maximum of 1851 g?m?2 for S. bicolor var. sudanese. The average biomass was 792 g?m?2 for B. hirta and 804 g?m?2 for S. alba in the two field studies, respectively. The glasshouse experiment used a loamy sand field soil inoculated with a natural fine sandy loam soil that was known to contain high populations of Verticillium dahliae. Soils at both field sites belonged to the sandy loam series, and efforts were made to maintain sufficient soil moisture for plant growth. Although the interest was to determine all volatile compounds in general, only methyl sulfide and dimethyl disulfide were identified and subsequently quantified. Depending on plant species and time of sampling (one to seven days after soil incorporation), 2.7 to 346.4?μg g ?1 plant dry weight for methyl sulfide and 0 to 283.2?μg g ?1 plant dry weight for dimethyl disulfide were found in the glasshouse experiment. In general, high concentrations of dimethyl disulfide and methyl sulfide appeared to have reduced V. dahliae colony counts in bioassay potato stem saps in the glasshouse experiment. However, the correlation was weak (R 2 ?=?0.31), but a relatively stronger correlation was obtained (R 2 ?=?0.58) when excluding B. oleracea and B. rapa from the regression. Dimethyl disulfide and methyl sulfide were nearly non-detectable in the field demonstration, consequently no disease assessment was made. In the field experiment, a production of 5.2?μg g ?1 plant dry weight for methyl sulfide and 1.2?μg g ?1 dry weight for dimethyl disulfide was found two days after soil incorporation of S. alba. Compared to the untreated control, total Fusarium oxysporum counts in field soil were significantly lower 39 days after S. alba incorporation. However, no significant impact was found on total Pythium counts. Soil population of citrus nematode (Tylenchulus semipenetrans) in the S. alba plots was significantly reduced to similar levels found in the untreated control 112 days after S. alba incorporation. Compared to the untreated control, soil density of non plant parasitic freeliving nematodes was higher 39 days after S. alba incorporation. The study demonstrated quantifiable production of methyl sulfide and dimethyl disulfide gases from a variety of plant species in glasshouse and natural field environments. Some beneficial effects against V. dahliae, F. oxysporum, and T. semipenetrans were observed. Additional studies are needed to further elucidate these complex chemical and biological interactions. 相似文献
16.
Oxidation of dimethyl sulfide byPseudomonas acidovorans DMR-11 isolated from peat biofilter 总被引:1,自引:0,他引:1
Summary
Pseudomonas acidovorans DMR-11, capable of oxidizing dimethyl sulfide (DMS), was isolated from peat biofilter. DMS as a sole carbon or energy source was not degraded, but it was co-degraded in the medium containing organic carbon sources. The removal rate of DMS in heat-treated glucose medium was 1.12×10–17 mole/h cell at 30 °C. Dimethyl sulfoxide (DMSO) was the only product of DMS oxidation and was formed stoichiometrically. DMS was reversibly evolved in excess of DMSO. The cell free extract of strain DMR-11 oxidized DMS in presence of NADPH. 相似文献
17.
Oremland RS Kiene RP Mathrani I Whiticar MJ Boone DR 《Applied and environmental microbiology》1989,55(4):994-1002
Characteristics of an obligately methylotrophic coccoid methanogen (strain GS-16) previously isolated from estuarine sediment are described. Growth was demonstrated on dimethyl sulfide (DMS) or trimethylamine (TMA), but not on methane thiol, methane thiol plus hydrogen, dimethyl disulfide, or methionine. DMS-grown cells were able to metabolize DMS and TMA simultaneously when inoculated into media containing substrate levels of these compounds. However, TMA-grown cells could not metabolize [C]DMS to CH(4), although they could convert [C]methanol to CH(4). These results suggest that metabolism of DMS proceeds along a somewhat different route than that of TMA and perhaps also that of methanol. The organism exhibited doubling times of 23 and 32 h for growth (25 degrees C) in mineral media on TMA and DMS, respectively. Doubling times were more rapid ( approximately 6 h) when the organisms were grown on TMA in complex broth. In mineral media, the fastest growth on DMS occurred between pH levels of 7.0 and 8.7, at 29 degrees C, and with 0.2 to 0.4 M Na and 0.04 M Mg. Somewhat different results occurred for growth on TMA in complex broth. Cells had a moles percent G+C value of 44.5% for their DNA. Growth on DMS, TMA, and methanol yielded stable carbon isotope fractionation factors of 1.044, 1.037, and 1.063, respectively. Fractionation factors for hydrogen were 1.203 (DMS) and 1.183 (TMA). 相似文献
18.
Benjamin C. Green David J. Suggett Alan Hills Michael Steinke 《Biogeochemistry》2012,110(1-3):163-172
Production of dimethyl sulfide (DMS) from marine samples is often quantified using gas chromatography techniques. Typically, these are labour intensive and have a slow sample turnover rate. Here we demonstrate the use of a portable fast DMS sensor (FDS) that utilises the chemiluminescent reaction of DMS and ozone to measure DMS production in aqueous samples, with a maximum frequency of 10?Hz. We have developed a protocol for quantifying DMS production that removes potential signal interference from other biogenic trace gases such as isoprene (2-methyl-1,3-butadiene) and hydrogen sulfide. The detection limit was 0.89?pM (0.02?ppbv) when using a DMS standard gas mixture. The lowest DMS production rates quantified with the FDS and verified using conventional gas chromatography with flame photometric detection (GC-FPD) were around 0.01?nmol?min?1. There was a strong correlation in DMS production when comparing the FDS and GC-FPD techniques with a range of marine samples (e.g., r 2 ?=?0.94 for Emiliania huxleyi). However, the combined dataset showed the FDS measured 22% higher DMS production than the GC-FPD, with the differences in rates likely due to interfering gases, for example hydrogen sulfide and isoprene. This possible overestimation of DMS production is smaller than the two-fold difference in DMS production between day and night samples from a culture of E. huxleyi. The response time of the instrument to changes in DMS production is method dependent (e.g., geometry of incubation vessel, bubble size) and was approximately 4?min under our conditions when using a culture of E. huxleyi (800?ml) with aeration at 100?ml?min?1. We suggest the FDS can reduce sample handling, is suitable for short- and long-term measurements of DMS production in algal cultures, and will widen the range of DMS research in marine environments. 相似文献
19.
Takami W Yoshida T Nojiri H Yamane H Omori T 《The Journal of General and Applied Microbiology》1999,45(2):69-75
In the present work, it was shown that the dimethyl sulfide (DMS) monooxygenase and the cumene dioxygenase catalyzed oxidation of various chlorinated ethenes, propenes, and butenes. The specific activities of these oxygenases were determined for C(2) to C(4) chlorinated olefins, and the oxidation rates ranged from 0.19 to 4.18 nmol.min(-1).mg(-1) of dry cells by the DMS monooxygenase and from 0.19 to 1.29 nmol.min(-1).mg(-1) of dry cells by the cumene dioxygenase. The oxidation products were identified by gas chromatography-mass spectrometry. Most chlorinated olefins were monooxygenated by the DMS monooxygenase to yield chlorinated epoxides. In the case of the cumene dioxygenase, the substrates lacking any chlorine atom on double-bond carbon atoms were dioxygenated, and those with chlorine atoms attaching to double-bond carbon atoms were monooxygenated to yield allyl alcohols. 相似文献
20.
Nevitt GA 《Integrative and comparative biology》2011,51(5):819-825
Information transfer influences food-web dynamics in the marine environment, but infochemicals involved in these processes are only beginning to be understood. Dimethylsulfoniopropionate (DMSP) is produced by phytoplankton and other marine algae, and has been studied primarily in the context of sulfur cycling and regulation of global climate. My laboratory has been investigating DMSP and its breakdown product, dimethyl sulfide as infochemicals associated with trophic interactions in marine habitats, including sub-Antarctic and coral reef ecosystems. Using a neuroecological approach, our work has established that these biogenic sulfur compounds serve as critical signal molecules in marine systems and provides us with a more mechanistic understanding of how climate change may impact information transfer within marine food webs. 相似文献