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1.
Formation of methylmercaptan and dimethylsulfide from methoxylated aromatic compounds in anoxic marine and fresh water sediments 总被引:2,自引:0,他引:2
Abstract Anaerobic formation of dimethylsulfide (DMS) and methylmercaptan (MSH) in anoxic sulfide-containing slurries from marine and fresh water sediments was stimulated by addition of syringate (4-hydroxy,3,5,-dimethoxybenzoate) and 3,4,5,-trimethoxybenzoate. The release of DMS and MSH occurred during the consumption of the aromatic monomers and ceased after their depletion. DMS was the dominant methylated sulfur compound in fresh water sediments, in contrast to marine sediments where MSH was predominant. No production of volatile organic sulfur compounds was observed in slurries containing gallate (3,4,5,-trihydroxybenzoate) or in autoclaved controled. About 50–65% of the methoxy carbon could be accounted for by peak accumulation of DMS and MSH. In the saline sediments, large amounts of CH4 were formed during the period when DMS and MSH disappeared. About 65–70% of the methylcarbon of the volatile methylated sulfur compounds (VMSC) could be accounted for in the produced CH4 . This study demonstrates a previously unknown microbial process by which DMS and MSH are formed during anaerobic decomposition of methoxylated aromatic compounds in marine and freshwater sediments. 相似文献
2.
From dilution series in defined mineral medium, a marine iregular coccoid methanogenic bacterium (strain MTP4) was isolated
that was able to grow on methanethiol as sole source of energy. The strain also grew on dimethylsulfide, mono-, di-, and trimethylamine,
methanol and acetate. On formate the organism produced methane without significant growth. Optimal growth on MT, with doubling
times of about 20 h, occurred at 30°C in marine medium. The isolate required p-aminobenzoate and a further not identified
vitamin. Strain MTP4 had a high tolerance to hydrogen sulfide but was very sensitive to mechanical forces or addition of detergents
such as Triton X-100 or sodium dodecylsulfate. Methanethiol was fermented by strain MTP4 according to the following equation:
相似文献
3.
Aerobic organisms degrade hydroaromatic compounds via the hydroaromatic pathway yielding protocatechuic acid which is further metabolized by oxygenase-mediated ring fission in the 3-oxoadipate pathway. No information exists on anaerobic degradation of hydroaromatics so far. We enriched and isolated from various sources of anoxic sediments several strains of rapidly growing gram-negative bacteria fermenting quinic (1,3,4,5-tetrahydroxy-cyclohexane-1-carboxylic acid) and shikimic acid (3,4,5-trihydroxy-1-cyclohexene-1-carboxylic acid) in the absence of external electron acceptors. Quinic and shikimic acid were the only ones utilized of more than 30 substrates tested. The marine isolates formed acetate, butyrate, and H2, whereas all freshwater strains formed acetate and propionate as typical fermentation products. Aromatic intermediates were not involved in this degradation. Characterization of the isolates, fermentation balances for both hydroaromatic compounds, and enzyme activities involved in one degradation pathway are presented.Abbreviations BV
benzyl viologen (1,1-dibenzyl-4,4-bipyridinium dichloride)
- CoA
coenzyme A
- CTAB
cetyltrimethylammonium bronide
- DCPIP
2,4-dichlorophenolindophenol
- DTT
1,4-dithiotheriol
- MV
methyl viologen (1,1-dimethyl-4,4-bipyridinium dichloride)
- Tricine
N-[tris-(hydroxymethyl)-methyl]-glycine
- Tris
tris-(hydroxymethyl)-aminomethane 相似文献
4.
Oxidative metabolism of inorganic sulfur compounds by bacteria 总被引:19,自引:0,他引:19
Donovan P. Kelly Jasvinder K. Shergill Wei-Ping Lu Ann P. Wood 《Antonie van Leeuwenhoek》1997,71(1-2):95-107
The history of the elucidation of the microbiology and biochemistry of the oxidation of inorganic sulfur compounds in chemolithotrophic bacteria is briefly reviewed, and the contribution of Martinus Beijerinck to the study of sulfur-oxidizing bacteria highlighted. Recent developments in the biochemistry, enzymology and molecular biology of sulfur oxidation in obligately and facultatively lithotrophic bacteria are summarized, and the existence of at least two major pathways of thiosulfate (sulfur and sulfide) oxidation confirmed. These are identified as the Paracoccus sulfur oxidation (or PSO) pathway and the S4intermediate (or S4I) pathway respectively. The former occurs in organisms such as Paracoccus (Thiobacillus) versutus and P. denitrificans, and possibly in Thiobacillus novellus and Xanthobacter spp. The latter pathway is characteristic of the obligate chemolithotrophs (e.g. Thiobacillus tepidarius, T. neapolitanus, T. ferrooxidans, T. thiooxidans) and facultative species such as T. acidophilus and T. aquaesulis, all of which can produce or oxidize tetrathionate when grown on thiosulfate. The central problem, as yet incompletely resolved in all cases, is the enzymology of the conversion of sulfane-sulfur (as in the outer [S-] atom of thiosulfate [-S-SO3-]), or sulfur itself, to sulfate, and whether sulfite is involved as a free intermediate in this process in all, or only some, cases. The study of inorganic sulfur compound oxidation for energetic purposes in bacteria (i.e. chemolithotrophy and sulfur photolithotrophy) poses challenges for comparative biochemistry. It also provides evidence of convergent evolution among diverse bacterial groups to achieve the end of energy-yielding sulfur compound oxidation (to drive autotrophic growth on carbon dioxide) but using a variety of enzymological systems, which share some common features. Some new data are presented on the oxidation of 35S-thiosulfate, and on the effect of other anions (selenate, molybdate, tu ngstate, chromate, vanadate) on sulfur compound oxidation, including observations which relate to the roles of polythionates and elemental sulfur as intermediates. 相似文献
5.
6.
Thomas J. Lyimo Arjan Pol Harry R. Harhangi Mike S.M. Jetten & Huub J.M. Op den Camp 《FEMS microbiology ecology》2009,70(3):151-160
The oxidation of dimethylsulfide and methanethiol by sulfate-reducing bacteria (SRB) was investigated in Tanzanian mangrove sediments. The rate of dimethylsulfide and methanethiol accumulation in nonamended sediment slurry (control) incubations was very low while in the presence of the inhibitors tungstate and bromoethanesulfonic acid (BES), the accumulation rates ranged from 0.02–0.34 to 0.2–0.4 nmol g FW sediment
7.
Lomans BP Leijdekkers P Wesselink JJ Bakkes P Pol A van der Drift C den Camp HJ 《Applied and environmental microbiology》2001,67(9):4017-4023
Methanethiol (MT) and dimethyl sulfide (DMS) have been shown to be the dominant volatile organic sulfur compounds in freshwater sediments. Previous research demonstrated that in these habitats MT and DMS are derived mainly from the methylation of sulfide. In order to identify the microorganisms that are responsible for this type of MT and DMS formation, several sulfide-rich freshwater sediments were amended with two potential methyl group-donating compounds, syringate and 3,4,5-trimethoxybenzoate (0.5 mM). The addition of these methoxylated aromatic compounds resulted in excess accumulation of MT and DMS in all sediment slurries even though methanogenic consumption of MT and DMS occurred. From one of the sediment slurries tested, a novel anaerobic bacterium was isolated with syringate as the sole carbon source. The strain, designated Parasporobacterium paucivorans, produced MT and DMS from the methoxy groups of syringate. The hydroxylated aromatic residue (gallate) was converted to acetate and butyrate. Like Sporobacterium olearium, another methoxylated aromatic compound-degrading bacterium, the isolate is a member of the XIVa cluster of the low-GC-content Clostridiales group. However, the new isolate differs from all other known methoxylated aromatic compound-degrading bacteria because it was able to degrade syringate in significant amounts only in the presence of sulfide. 相似文献
8.
Reduction of nitroaromatic compounds by anaerobic bacteria isolated from the human gastrointestinal tract 总被引:3,自引:0,他引:3
F Rafil W Franklin R H Heflich C E Cerniglia 《Applied and environmental microbiology》1991,57(4):962-968
Human intestinal microbial flora were screened for their abilities to reduce nitroaromatic compounds by growing them on brain heart infusion agar plates containing 1-nitropyrene. Bacteria metabolizing 1-nitropyrene, detected by the appearance of clear zones around the colonies, were identified as Clostridium leptum, Clostridium paraputrificum, Clostridium clostridiiforme, another Clostridium sp., and a Eubacterium sp. These bacteria produced aromatic amines from nitroaromatic compounds, as shown by thin-layer chromatography, high-pressure liquid chromatography, and biochemical tests. Incubation of three of these bacteria with 1-nitropyrene, 1,3-dinitropyrene, and 1,6-dinitropyrene inactivated the direct-acting mutagenicity associated with these compounds. Menadione and o-iodosobenzoic acid inhibited nitroreductase activity in all of the isolates, indicating the involvement of sulfhydryl groups in the active site of the enzyme. The optimum pH for nitroreductase activity was 8.0. Only the Clostridium sp. required added flavin adenine dinucleotide for nitroreductase activity. The nitroreductases were constitutive and extracellular. An activity stain for the detection of nitroreductase on anaerobic native polyacrylamide gels was developed. This activity stain revealed only one isozyme in each bacterium but showed that the nitroreductases from different bacteria had distinct electrophoretic mobilities. 相似文献
9.
Biodegradation of aromatic compounds byRhodopseudomonas blastica andRhodospirillum rubrum appears to be lacking in the literature. The above species grew phototrophically (illuminated anaerobic conditions) on a variety of organic compounds. They were found to degrade benzoate, benzyl alcohol, 4-hydroxy-3,5-dimethoxybenzoate (Syringate) and 4-hydroxy-3-methoxybenzoate (vanillate). The ability of the above species to photocatabolize aromatic compounds indicates that these organisms may be ecologically significant as scavengers of aromatic derivatives in illuminated anaerobic habitats in nature. 相似文献
10.
Two strains of new strictly anaerobic, gramnegative bacteria were enriched and isolated from a freshwater (strain WoG13) and a saltwater (strain CuG11) anoxic sediment with glutarate as sole energy source. Strain WoG13 formed spores whereas strain CuG11 did not. Both strains were rod-shaped, motile bacteria growing in carbonate-buffered, sulfide-reduced mineral medium supplemented with 2% of rumen fluid. Both strains fermented glutarate to butyrate, isobutyrate, CO2, and small amounts of acetate. With methylsuccinate, the same products were formed, and succinate was fermented to propionate and CO2. No sugars, amino acids or other organic acids were used as substrates. Molar growth yields (Ys) were very small (0.5–0.9 g cell dry mass/mol dicarboxylate). Cells of strain WoG13 contained no cytochromes, and the DNA base ratio was 49.0±1.4 mol% guanine-plus-cytosine. Enzyme activities involved in glutarate degradation could bedemonstrated in cell-free extracts of strain WoG13. A pathway of glutarate fermentation via decarboxylation of glutaconyl-CoA to crotonyl-CoA is suggested which forms butyrate and partly isobutyrate by subsequent isomerization. 相似文献
11.
Anaerobic enrichments with methoxylated aromatic compounds as substrates (vanillate, syringate, trimethoxycinnamate) were inoculated from freshwater mud and sewage sludge samples. In 12 out of 16 cultures the same type of rod-shaped, motile bacteria was selectively enriched. Two strains, NZva16 and NZva24, were isolated in pure culture and recognized as Acetobacterium woodii by comparison with the type strain (DSM 1030).All three Acetobacterium strains were able to grow with all 10 of the tested aromatic compounds containing methoxyl groups. In the presence of bicarbonate, these substrates were used as sole organic electron donors and carbon sources. UV-absorption spectra revealed that the aromatic rings were not degraded, and that the corresponding hydroxy derivatives of the methoxylated compounds were formed. The only further fermentation product formed was acetate. When equimolar concentrations of the methoxylated benzoic acid derivatives were applied, the growth yields were proportional to the number of methoxyl groups per molecule. Methoxyl groups or methanol were metabolized by homoacetate fermentation: in the presence of bicarbonate 4 mol of acetate. In case of the methoxylated cinnamic acid derivatives less acetate was formed and the corresponding hydroxy derivatives of phenylpropionic acid appeared as a result of the double bond reduction in the acrylate side chain. In comparison to the benzoate derivatives with the same number of methoxyl groups, higher growth yields were obtained with the cinnamate derivatives. 相似文献
12.
Reduction of nitroaromatic compounds by anaerobic bacteria isolated from the human gastrointestinal tract. 总被引:2,自引:6,他引:2 下载免费PDF全文
Human intestinal microbial flora were screened for their abilities to reduce nitroaromatic compounds by growing them on brain heart infusion agar plates containing 1-nitropyrene. Bacteria metabolizing 1-nitropyrene, detected by the appearance of clear zones around the colonies, were identified as Clostridium leptum, Clostridium paraputrificum, Clostridium clostridiiforme, another Clostridium sp., and a Eubacterium sp. These bacteria produced aromatic amines from nitroaromatic compounds, as shown by thin-layer chromatography, high-pressure liquid chromatography, and biochemical tests. Incubation of three of these bacteria with 1-nitropyrene, 1,3-dinitropyrene, and 1,6-dinitropyrene inactivated the direct-acting mutagenicity associated with these compounds. Menadione and o-iodosobenzoic acid inhibited nitroreductase activity in all of the isolates, indicating the involvement of sulfhydryl groups in the active site of the enzyme. The optimum pH for nitroreductase activity was 8.0. Only the Clostridium sp. required added flavin adenine dinucleotide for nitroreductase activity. The nitroreductases were constitutive and extracellular. An activity stain for the detection of nitroreductase on anaerobic native polyacrylamide gels was developed. This activity stain revealed only one isozyme in each bacterium but showed that the nitroreductases from different bacteria had distinct electrophoretic mobilities. 相似文献
13.
Anaerobic degradation of methylmercaptan and dimethyl sulfide by newly isolated thermophilic sulfate-reducing bacteria. 总被引:1,自引:4,他引:1 下载免费PDF全文
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
14.
Anaerobic oxidation of the aromatic plant hydrocarbon p-cymene by newly isolated denitrifying bacteria 总被引:2,自引:0,他引:2
The capability of nitrate-reducing bacteria to degrade alkyltoluenes in the absence of molecular oxygen was investigated
with the three isomers of xylene, ethyltoluene, and isopropyltoluene (cymene) in enrichment cultures inoculated with freshwater
mud. Denitrifying enrichment cultures developed most readily (within 4 weeks) with p-cymene, a natural aromatic hydrocarbon occurring in plants, and with m-xylene (within 6 weeks). Enrichment of denitrifiers that utilized m-ethyltoluene and p-ethyltoluene was slow (within 8 and 12 weeks, respectively); no enrichment cultures were obtained with the other alkylbenzenes
within 6 months. Anaerobic degradation of p-cymene, which has not been reported before, was studied in more detail. Two new types of denitrifying bacteria with oval
cells, strains pCyN1 and pCyN2, were isolated; they grew on p-cymene (diluted in an inert carrier phase) and nitrate with doubling times of 12 and 16 h, respectively. Strain pCyN1, but
not strain pCyN2, also utilized p-ethyltoluene and toluene. Both strains grew with some alkenoic monoterpenes structurally related to p-cymene, e.g., α-terpinene. In addition, the isolates utilized p-isopropylbenzoate, and mono- and dicarboxylic aliphatic acids. Determination of the degradation balance of p-cymene and growth with acetate and nitrate indicated the capacity for complete oxidation of organic substrates under anoxic
conditions. Adaptation studies with cells of strain pCyN1 suggest the existence of at least two enzyme systems for anaerobic
alkylbenzene utilization, one metabolizing p-cymene and p-ethyltoluene, and the other metabolizing toluene. Excretion of p-isopropylbenzoate during growth on p-cymene indicated that the methyl group is the site of initial enzymatic attack. Although both strains were facultatively
aerobic, as revealed by growth on acetate under air, growth on p-cymene under oxic conditions was observed only with strain pCyN1. Strains pCyN1 and pCyN2 are closely related to members
of the Azoarcus-Thauera cluster within the β-subclass of the Proteobacteria, as revealed by 16S rRNA gene sequence analysis. This cluster encompasses
several described denitrifiers that oxidize toluene and other alkylbenzenes.
Received: 15 July 1998 / Revision received: 29 July 1999 / Accepted: 2 August 1999 相似文献
15.
Formation of volatile sulfur compounds and metabolism of methionine and other sulfur compounds in fermented food 总被引:3,自引:0,他引:3
The formation of volatile sulfur compounds (VSC) in fermented food is a subject of interest. Such compounds are essential
for the aroma of many food products like cheeses or fermented beverages, in which they can play an attractive or a repulsive
role, depending on their identity and their concentration. VSC essentially arise from common sulfur-bearing precursors, methionine
being the most commonly found. In the first section of this paper, the main VSC found in cheese, wine, and beer are reviewed.
It is shown that a wide variety of VSC has been evidenced in these food products. Because of their low odor threshold and
flavor notes, these compounds impart essential sensorial properties to the final product. In the second section of this review,
the main (bio)chemical pathways leading to VSC synthesis are presented. Attention is focused on the microbial/enzymatic phenomena—which
initiate sulfur bearing precursors degradation—leading to VSC production. Although chemical reactions could also play an important
role in this process, this aspect is not fully developed in our review. The main catabolic pathways leading to VSC from the
precursor methionine are presented. 相似文献
16.
17.
硫化氢(H_2S)是继一氧化氮(NO)和一氧化碳(CO)后发现的第3种气态信号分子,但其细菌生理学研究才刚刚起步。本文根据作者对奥内达希瓦氏菌的研究,结合新近文献,就细菌的H_2S产生机理及其生理功能作了较为全面的阐述。细菌的H_2S产生途径主要有2条,一是通过降解半胱氨酸产生,二是通过厌氧呼吸产生。产生的H_2S除可为互生性微生物提供能源、供氢体和无机矿质营养外,还具有抑制竞争性微生物的生长,有效占领生态位的作用。H_2S在氧化应答中也起着重要的作用,一方面可抑制过氧化氢酶活性,增加过氧化氢对细菌的杀灭效果;另一方面可作为信号分子激活细菌的氧化应答,诱导拮抗系统的表达,保护细胞免受氧化损伤。这两种看似"矛盾"的作用与H_2S的处理时间有关:短时间处理以抑制为主,而延长处理时间则以保护为主。细菌H_2S产生机理及生理功能的阐明可为硫元素生物地球化学循环规律的揭示和感染性病原细菌的控制提供有益的参考。 相似文献
18.
Masae Horinouchi Takako Yoshida Hideaki Nojiri Hisakazu Yamane Toshio Omori 《Biotechnology letters》1999,21(11):929-933
As a result of the determination of dimethyl sulfide (DMS) oxidizing activity of bacterial aromatic compound oxygenases, multicomponent monooxygenases (DmpKLMNOP from Pseudomonas sp. CF600, AphKLMNOP from Comamonas testosteroni TA441, and TodABCDEF from Pseudomonas sp. JS150), single component monooxygenases (TfdB from Pseudomonas putida EST4011 and XylMA from Pseudomonas putida mt-2), and dioxygenases (CumA1A2A3A4 from Pseudomonas fluorescens IP01 and PahAaAbAcAd from Pseudomonas putida OUS82) showed DMS-oxidizing activity, while CarAaAcAd from Pseudomonas sp. CA10 and SoxC from Rhodococcus sp. IGTS8 did not. These results indicate the possibilities that these oxygenases might oxidize DMS to DMSO under the natural condition in the environment.Present address: Laboratory of Microbiology, The Institute of Physical and Chemical Research (RIKEN), 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan 相似文献
19.
A. García-Ruiz B. Bartolomé C. Cueva P.J. Martín-Álvarez M.V. Moreno-Arribas 《Journal of applied microbiology》2009,107(3):1042-1053
Aims: To investigate the inactivation properties of different classes of phenolic compounds present in wine against two wine isolates of Lactobacillus hilgardii and Pediococcus pentosaceus , and to explore their inactivation mechanism.
Methods and Results: After a first screening of the inactivation potency of 21 phenolic compounds (hydroxybenzoic and hydroxycinnamic acids, phenolic alcohols, stilbenes, flavan-3-ols and flavonols) at specific concentrations, the survival parameters (MIC and MBC) of the most active compounds were determined. For the L. hilgardii strain, the flavonols morin and kaempferol showed the strongest inactivation (MIC values of one and 5 mg l Conclusions: The antibacterial activity of wine phenolics against L. hilgardii and P. pentosaceus was dependent on the phenolic compound tested, and led not only to bacteria inactivation, but also to the cell death. Significance and Impact of the Study: New information about the inactivation properties of wine lactic acid bacteria by phenolic compounds is presented. It opens up a new area of study for selecting/obtaining wine phenolic preparations with potential applications as a natural alternative to SO 20.
Simone Dannenberg Michael Kroder Waltraud Dilling Heribert Cypionka 《Archives of microbiology》1992,158(2):93-99
All of fourteen sulfate-reducing bacteria tested were able to carry out aerobic respiration with at least one of the following electron donors: H2, lactate, pyruvate, formate, acetate, butyrate, ethanol, sulfide, thiosulfate, sulfite. Generally, we did not obtain growth with O2 as electron acceptor. The bacteria were microaerophilic, since the respiration rates increased with decreasing O2 concentrations or ceased after repeated O2 additions. The amounts of O2 consumed indicated that the organic substrates were oxidized incompletely to acetate; only Desulfobacter postgatei oxidized acetate with O2 completely to CO2. Many of the strains oxidized sulfite (completely to sulfate) or sulfide (incompletely, except Desulfobulbus propionicus); thiosulfate was oxidized only by strains of Desulfovibrio desulfuricans; trithionate and tetrathionate were not oxidized by any of the strains. With Desulfovibrio desulfuricans CSN and Desulfobulbus propionicus the oxidation of inorganic sulfur compounds was characterized in detail. D. desulfuricans formed sulfate during oxidation of sulfite, thiosulfate or elemental sulfur prepared from polysulfide. D. propionicus oxidized sulfite and sulfide to sulfate, and elemental sulfur mainly to thiosulfate. A novel pathway that couples the sulfur and nitrogen cycles was detected: D. desulfuricans and (only with nitrite) D. propionicus were able to completely oxidize sulfide coupled to the reduction of nitrate or nitrite to ammonia. Cell-free extracts of both strains did not oxidize sulfide or thiosulfate, but formed ATP during oxidation of sulfite (37 nmol per 100 nmol sulfite). This, and the effects of AMP, pyrophosphate and molybdate on sulfite oxidation, suggested that sulfate is formed via the (reversed) sulfate activation pathway (involving APS reductase and ATP sulfurylase). Thiosulfate oxidation with O2 probably required a reductive first step, since it was obtained only with energized intact cells.Abbreviations
CCCP
carbonyl cyanide m-chlorophenylhydrazone
-
APS
adenosine phosphosulfate or adenylyl sulfate 相似文献
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