Sphingomonas carri sp. nov., isolated from a car air-conditioning system.

Science.gov (United States)

Lee, Hyosun; Kim, Dong-Uk; Lee, Suyeon; Yun, Jungpyo; Park, Sooyeon; Yoon, Jung-Hoon; Park, So Yoon; Ka, Jong-Ok

2017-10-01

A Gram-stain-negative, yellow-pigmented bacterial strain, designated PR0302 T , was isolated from a car evaporator core collected in Korea. The cells were strictly aerobic, non-spore-forming and rod-shaped. The strain grew at 15-37 °C (optimum, 25 °C), at pH 6.0-8.0 (optimum, 7.0) and in the presence of 0-1 % (w/v) NaCl. Phylogenetically, the strain was closely related to members of the genus Sphingomonas(97.04-91.22 % 16S rRNA gene sequence similarities) and showed the highest sequence similarity of 97.04 % to Sphingomonas kyeonggiensis THG-DT81 T . It contained C16 : 0, summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c) and C14 : 0 2-OH as the predominant fatty acids and Q-10 as the major ubiquinone. The predominant polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and sphingoglycolipid. The major polyamine was sym-homospermidine. The serine palmitoyl transferase gene (spt) was detected and sphingolipid synthesis was confirmed. The mean DNA G+C content of the strain was 67.8±0.5 mol%. DNA-DNA relatedness between strain PR0302 T and closely related type strains of Sphingomonas species was less than 30 %. The low levels of DNA-DNA relatedness identified strain PR0302 T as a member of a novel species in the genus Sphingomonas. Based on phenotypic, genotypic and chemotaxonomic data, strain PR0302 T represents a novel species in the genus Sphingomonas, for which the name Sphingomonas carri sp. nov. is proposed. The type strain is PR0302 T (=KACC 18487 T =NBRC 111532 T ).

Changes to the structure of Sphingomonas spp. communities associated with biodegradation of the herbicide isoproturon in soil.

Science.gov (United States)

Shi, Shengjing; Bending, Gary D

2007-04-01

The phenyl-urea herbicide isoproturon is a major contaminant of surface and ground-water in agricultural catchments. Earlier work suggested that within-field spatial variation of isoproturon degradation rate resulted from interactions between catabolizing Sphingomonas spp. and pH. In the current study, changes to the structure of Sphingomonas communities during isoproturon catabolism were investigated using Sphingomonas-specific 16S rRNA gene primers. Growth-linked catabolism at high-pH (>7.5) sites was associated with the appearance of multiple new denaturing gradient gel electrophoresis (DGGE) bands. At low-pH sites, there was no change in DGGE banding at sites in which there was cometabolism, but at sites in which there was growth-linked catabolism, degradation was associated with the appearance of a new band not present at high pH sites. Sequencing of DGGE bands indicated that a strain related to Sphingomonas mali proliferated at low pH sites, while strain Sphingomonas sp. SRS2, a catabolic strain identified in earlier work, together with several further Sphingomonas spp., proliferated at high-pH sites. The data indicate that degradation was associated with complex changes to the structure of Sphingomonas spp. communities, the precise nature of which was spatially variable.

Isolation and characterization of a novel polychlorinated biphenyl-degrading bacterium, Paenibacillus sp. KBC101

Energy Technology Data Exchange (ETDEWEB)

Sakai, M.; Ezaki, S.; Suzuki, N.; Kurane, R. [Kubota Corporation, Ryuugasaki City (Japan). Biotechnology Research Centre

2005-07-01

The biphenyl-utilizing bacterial strain KBC101 has been newly isolated from soil. Biphenyl-grown cells of KBC101 efficiently degraded di- to nonachlorobiphenyls. The isolate was identified as Paenibacillus sp. with respect to its 16S rDNA sequence and fatty acid profiles, as well as various biological and physiological characteristics. In the case of highly chlorinated biphenyl (polychlorinated biphenyl; PCB) congeners, the degradation activities of this strain were superior to those of the previously reported strong PCB degrader, Rhodococcus sp. RHA1. Recalcitrant coplanar PCBs, such as 3,4,3',4'-CB, were also efficiently degraded by strain KBC101 cells. This is the first report of a representative of the genus Paenibacillus capable of degrading PCBs. In addition to growth of biphenyl, strain KBC101 could grow on dibenzofuran, xanthene, benzophenone, anthrone, phenanthrene, napthalene, fluorene, fluoranthene, and chrysene as sole sources of carbon and energy. Paenibacillus sp. strain KBC101 presented heterogeneous degradation profiles toward various aromatic compounds. (orig.)

Sphingomonas frigidaeris sp. nov., isolated from an air conditioning system.

Science.gov (United States)

Lee, Yunho; Jeon, Che Ok

2017-10-01

A strictly aerobic Gram-stain-negative bacterium, designated strain KER25-10 T , was isolated from a laboratory air conditioning system in South Korea. Cells were yellow-pigmented, non-motile rods showing catalase- and oxidase-positive reactions. The strain grew at pH 4.0-9.0 (optimum, pH 6.0-7.0) and 10-40 °C (optimum, 30 °C) and in the presence of 0-3 % (w/v) NaCl (optimum, 0 %). The G+C content of the genomic DNA was 65.1 mol%. Strain KER25-10 T contained ubiquinone-10 (Q-10) as the predominant isoprenoid quinone and C16 : 0, C17 : 1ω6c, summed feature 3 (comprising C16 : 1ω7c and/or C16 : 1ω6c) and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c) as the major fatty acids. The major polar lipids were sphingoglycolipid, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylcholine. Only spermidine was detected as the polyamine. Phylogenetic analysis based on 16S rRNA sequences indicated that strain KER25-10 T formed a distinct phylogenetic lineage within the genus Sphingomonas of the family Sphingomonadaceae and the strain was most closely related to Sphingomonas kyeonggiense THG-DT81 T with a 96.8 % 16S rRNA gene sequence similarity. On the basis of phenotypic, chemotaxonomic and molecular features, strain KER25-10 T clearly represents a novel species of the genus Sphingomonas, for which the name Sphingomonas frigidaeris sp. nov. is proposed. The type strain is KER25-10 T (=KACC 19285 T =JCM 32053 T ).

The novel oleaginous bacterium Sphingomonas sp. EGY1 DSM 29616: a value added platform for renewable biodiesel.

Science.gov (United States)

Amer, Nehad N; Elbahloul, Yasser; Embaby, Amira M; Hussein, Ahmed

2017-07-01

Oleaginous microorganisms are regarded as efficient, renewable cell factories for lipid biosynthesis, a biodiesel precursor, to overwhelm the cosmopolitan energy crisis with affordable investment capital costs. Present research highlights production and characterization of lipids by a newly isolated oleaginous bacterium, Sphingomonas sp. EGY1 DSM 29616 through an eco-friendly approach. Only sweet whey [42.1% (v/v)] in tap water was efficiently used as a growth medium and lipid production medium to encourage cell growth and trigger lipid accumulation simultaneously. Cultivation of Sphingomonas sp. EGY1 DSM 29616 in shake flasks resulted in the accumulation of 8.5 g L -1 lipids inside the cells after 36 h at 30 °C. Triglycerides of C16:C18 saturated and unsaturated fatty acids showed a similar pattern to tripalmitin or triolein; deduced from gas chromatography (GC), thin layer chromatography (TLC), and Matrix-assisted laser desorption/ionization time-of-flight-mass spectra analysis (MALDI-TOF-MS) analyses. Batch cultivation 2.5 L in a laboratory scale fermenter led to 13.8 g L -1 accumulated lipids after 34 h at 30 °C. Present data would underpin the potential of Sphingomonas sp. EGY1 DSM 29616 as a novel renewable cell factory for biosynthesis of biodiesel.

Crystallization and preliminary X-ray analysis of alginate importer from Sphingomonas sp. A1

International Nuclear Information System (INIS)

Maruyama, Yukie; Itoh, Takafumi; Nishitani, Yu; Mikami, Bunzo; Hashimoto, Wataru; Murata, Kousaku

2012-01-01

Alginate importer from Sphingomonas sp. A1 is a member of the ABC transporter superfamily that directly transports alginate polysaccharide into the cytoplasm. Crystals of alginate importer in complex with the periplasmic binding protein AlgQ2 diffracted X-rays to 3.3 Å resolution. Sphingomonas sp. A1 directly incorporates alginate polysaccharides through a ‘superchannel’ comprising a pit on the cell surface, alginate-binding proteins in the periplasm and an ABC transporter (alginate importer) in the inner membrane. Alginate importer, consisting of four subunits, AlgM1, AlgM2 and two molecules of AlgS, was crystallized in the presence of the binding protein AlgQ2. Preliminary X-ray analysis showed that the crystal diffracted to 3.3 Å resolution and belonged to space group P2 1 2 1 2 1 , with unit-cell parameters a = 72.5, b = 136.8, c = 273.3 Å, suggesting the presence of one complex in the asymmetric unit

Sphingomonas qilianensis sp. nov., Isolated from Surface Soil in the Permafrost Region of Qilian Mountains, China.

Science.gov (United States)

Piao, Ai-Lian; Feng, Xiao-Min; Nogi, Yuichi; Han, Lu; Li, Yonghong; Lv, Jie

2016-04-01

A Gram-stain-negative, strictly aerobic, non-motile and rod-shaped bacterial strain, designated X1(T), was isolated from the permafrost region of Qilian Mountains in northwest of China. Phylogenetic analyses of 16S rRNA gene sequence revealed that strain X1(T) was a member of the genus Sphingomonas and shared the highest 16S rRNA gene sequence similarity with Sphingomonas oligophenolica JCM 12082(T) (96.9%), followed by Sphingomonas glacialis CGMCC 1.8957(T) (96.7%) and Sphingomonas alpina DSM 22537(T) (96.4%). Strain X1(T) was able to grow at 15-30 °C, pH 6.0-10.0 and with 0-0.3% NaCl (w/v). The DNA G+C content of the isolate was 64.8 mol%. Strain X1(T)-contained Q-10 as the dominant ubiquinone and C(18:1)ω7c, C(16:1)ω7c, C(16:0) and C(14:0) 2-OH as the dominant fatty acids. The polar lipid profile of strain XI(T)-contained sphingoglycolipid, phosphatidylglycerol, phosphatidylethanolamine, one unidentified glycolipid and two unidentified phospholipid. Due to the phenotypic and genetic distinctiveness and other characteristic studied in this article, we consider X1(T) as a novel species of the genus Sphingomonas and propose to name it Sphingomonas qilianensis sp. nov. The type strain is X1(T) (=CGMCC 1.15349(T) = KCTC 42862(T)).

Genetic labelling and application of the isoproturon-mineralizing Sphingomonas sp. strain SRS2 in soil and rhizosphere.

Science.gov (United States)

Kristensen, K E; Jacobsen, C S; Hansen, L H; Aamand, J; Morgan, J A W; Sternberg, C; Sørensen, S R

2006-09-01

To construct a luxAB-labelled Sphingomonas sp. strain SRS2 maintaining the ability to mineralize the herbicide isoproturon and usable for monitoring the survival and distribution of strain SRS2 on plant roots in laboratory systems. We inserted the mini-Tn5-luxAB marker into strain SRS2 using conjugational mating. In the transconjugant mutants luciferase was produced in varying levels. The mutants showed significant differences in their ability to degrade isoproturon. One luxAB-labelled mutant maintained the ability to mineralize isoproturon and was therefore selected for monitoring colonization of barley roots. We successfully constructed a genetically labelled isoproturon-mineralizing-strain SRS2 and demonstrated its ability to survive in soil and its colonization of rhizosphere. The construction of a luxAB-labelled strain SRS2 maintaining the degradative ability, provides a powerful tool for ecological studies serving as the basis for evaluating SRS2 as a bioremediation agent.

The efficacy of an oxidation pond in mineralizing some industrial waste products with special reference to fluorene degradation: A case study

Energy Technology Data Exchange (ETDEWEB)

Ahmed, M.T.; Dewedar, A.; Mekki, L.; Diab, A.

1999-07-01

The efficacy of the oxidation pond on the outskirts of the 10th of Ramadan, the main industrial city in Egypt, was examined. Samples of wastewater collected from the inlet and the outlet were screened for some priority pollutants. Acenaphethene and fluorene were the most frequently detected polycyclic aromatic hydrocarbons, while dimethyl phthalate was the most frequently detected phthalate ester. The spectrum of pollutants, their concentrations and frequencies were similar in the inlet and the outlet, indicating an inferior mineralization capability of the pond. Several degradative bacterial strains were isolated from the pond and grown on M56 minimal media supplemented with different pollutants as the carbon source. The efficacy of pure and mixed cultures to break down fluorene, the most frequently detected pollutant was examined. Fluorene degradation was fast in the first 10 days, the followed by a slow phase. Mixed culture had a higher rate of fluorene degradation in comparison to pure cultures. High performance liquid chromatography analysis of fluorene degradation showed three degradative metabolites. But GC/MS analysis detected one compound, identified as acetamide. The present work has indicated the poor efficacy of the pond. Lack of primary treatment of industrial effluent at factory level, coupled with shock loads of toxicants that may damage the microorganisms and their degradative capabilities are presumably main factors behind such inferior performance. Moreover, the type of pollutants discharged into the pond tend to fluctuate and change depending on the rate from the factories discharge and work shifts. Such irregular feeding of persistent pollutants may have led to a wash out of specialized strains of bacteria capable to degrade such persistent pollutants.

Genetic labelling and application of the isoproturon-mineralizing Sphingomonas sp. strain SRS2 in soil and rhizosphere

DEFF Research Database (Denmark)

Kristensen, K.E.; Jacobsen, C.S.; Hansen, L.H.

2006-01-01

AIMS: To construct a luxAB-labelled Sphingomonas sp. strain SRS2 maintaining the ability to mineralize the herbicide isoproturon and usable for monitoring the survival and distribution of strain SRS2 on plant roots in laboratory systems. METHODS AND RESULTS: We inserted the mini-Tn5-luxAB marker...... into strain SRS2 using conjugational mating. In the transconjugant mutants luciferase was produced in varying levels. The mutants showed significant differences in their ability to degrade isoproturon. One luxAB-labelled mutant maintained the ability to mineralize isoproturon and was therefore selected...... for monitoring colonization of barley roots. CONCLUSIONS: We successfully constructed a genetically labelled isoproturon-mineralizing-strain SRS2 and demonstrated its ability to survive in soil and its colonization of rhizosphere. SIGNIFICANCE AND IMPACT OF THE STUDY: The construction of a luxAB-labelled strain...

Degradation of naphthalene and fluorene by radiolysis using accelerated electrons

International Nuclear Information System (INIS)

Flores de Jesus, I.

2003-01-01

The volume of the dangerous wastes in global level is causing the poisoning of planet and all of the ecosystems, degrading the life level of millions of humans and causing serious problems in the public health. Since a years ago the volumes of organic effluents generated by the few industry and small populations were so tiny that a natural debugger process in a time and space delimited, acquiring again their natural characteristics and they could be used again. Nowadays these wastes are so numerous and precise in some cases that the capacity of natural purification in the receiving channel is not enough, in addition to the difficulty to treat them in conventional processes, this leads to the decrease in the water's quality making impossible its future use and causing with this a serious ecological problem. This fact has motivated the development of measures that tend to the conservation of the environment and in consequence, the development of debugger technologies with no generation of sub products that often are more dangerous than the originals, due to the previous thing, the treatment by means of radiation of the water is impelled since is a method that allows to degrade or to eliminate in simultaneous form pathogenic microorganisms and organic substances. The radiation by means of electrons beams is a method of advanced treatment who allows to degrade organic compounds, transforming them in compounds with less molecular weight, and in the best of the cases until its oxidation to carbon dioxide and water. In the present thesis the objective is the study of naphthalene and fluorene degradation by means of radiation with electron beams, establishing the operating conditions of the accelerator of Pelletron type. This research is supported by the Instituto Nacional de Investigaciones Nucleares, of a joint way with a series of antecedents in this subject, established in previous research with respect to the treatment of residual waters in a great scale, giving

Draft Genome Sequence of Isoproturon-Mineralizing Sphingomonas sp. SRS2, Isolated from an Agricultural Field in the United Kingdom.

Science.gov (United States)

Nielsen, Tue Kjærgaard; Sørensen, Sebastian R; Hansen, Lars Hestbjerg

2015-05-28

Sphingomonas sp. SRS2 was the first described pure strain that is capable of mineralizing the phenylurea herbicide isoproturon and some of its related compounds. This strain has been studied thoroughly and shows potential for bioremediation purposes. We present the draft genome sequence of this bacterium, which will aid future studies. Copyright © 2015 Nielsen et al.

Classification of Rhizomonas suberifaciens, an unnamed Rhizomonas species, and Sphingomonas spp. in rRNA superfamily IV.

Science.gov (United States)

van Bruggen, A H; Jochimsen, K N; Steinberger, E M; Segers, P; Gillis, M

1993-01-01

Thermal melting profiles of hybrids between 3H-labeled rRNA of Rhizomonas suberifaciens, the causal agent of corky root of lettuce, and chromosomal DNAs from 27 species of gram-negative bacteria indicated that the genus Rhizomonas belongs to superfamily IV of De Ley. On the basis of the melting temperatures of DNA hybrids with rRNAs from the type strains of R. suberifaciens, Sphingomonas paucimobilis, and Sphingomonas capsulata, Rhizomonas strains constitute a separate branch in superfamily IV, which is closely related to but separate from branches containing Zymomonas mobilis, Sphingomonas spp., and S. capsulata. Sphingomonas yanoikuyae and Rhizomonas sp. strain WI4 are located toward the base of the Rhizomonas rRNA branch. DNA-DNA hybridization indicated that S. yanoikuyae is equidistant from Rhizomonas sp. strain WI4 and S. paucimobilis. Sequences of 270 bp of 16S ribosomal DNAs from eight strains of Rhizomonas spp., eight strains of Sphingomonas spp., and Agrobacterium tumefaciens indicated that S. yanoikuyae and Rhizomonas sp. strains WI4 and CA16 are genetically more closely related to R. suberifaciens than to Sphingomonas spp. Thus, S. yanoikuyae may need to be transferred to the genus Rhizomonas on the basis of the results of further study.

Mineralization of soil-aged isoproturon and isoproturon metabolites by Sphingomonas sp. strain SRS2.

Science.gov (United States)

Johannesen, Helle; Sørensen, Sebastian R; Aamand, Jens

2003-01-01

The aim of the study was to determine the effect of aging of the herbicide isoproturon and its metabolites monodesmethyl-isoproturon and 4-isopropyl-aniline in agricultural soil on their availability to the degrading bacterium Sphingomonas sp. strain SRS2. The 14C-ring-labeled isoproturon, monodesmethyl-isoproturon, and 4-isopropyl-aniline were added to sterilized soil and stored for 1, 49, 71, or 131 d before inoculation with strain SRS2. The availability of the compounds was estimated from the initial mineralization and the amount of 14CO2 recovered after 120 d of incubation. Aging in soil for 131 d reduced the initial mineralization of isoproturon and monodesmethyl-isoproturon and, in the case of isoproturon, also reduced the recovery of 14CO2. Initial mineralization and recovery of 14CO2 from aged 4-isopropyl-aniline were slightly reduced, but less 14CO2 was generally produced than with isoproturon or monodesmethyl-isoproturon. Thus, recovery of 14CO2 from 14C-isoproturon and 14C-monodesmethyl-isoproturon was 50.7 to 64.4% of the initially added 14C, while recovery from 14C-4-isopropyl-aniline was only 11.7 to 17.0%. Sorption measurements revealed similar Freundlich constants (K(f)) for isoproturon and monodesmethyl-isoproturon, whereas K(f) for 4-isopropyl-aniline was more than fivefold greater. The findings imply that in soil, partial degradation of isoproturon to 4-isopropyl-aniline may lead to reduced mineralization of the herbicide due to sorption of the aniline moiety.

Proteomic Profiling of the Dioxin-Degrading Bacterium Sphingomonas wittichii RW1

Directory of Open Access Journals (Sweden)

David R. Colquhoun

2012-01-01

Full Text Available Sphingomonas wittichii RW1 is a bacterium of interest due to its ability to degrade polychlorinated dioxins, which represent priority pollutants in the USA and worldwide. Although its genome has been fully sequenced, many questions exist regarding changes in protein expression of S. wittichii RW1 in response to dioxin metabolism. We used difference gel electrophoresis (DIGE and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS to identify proteomic changes induced by growth on dibenzofuran, a surrogate for dioxin, as compared to acetate. Approximately 10% of the entire putative proteome of RW1 could be observed. Several components of the dioxin and dibenzofuran degradation pathway were shown to be upregulated, thereby highlighting the utility of using proteomic analyses for studying bioremediation agents. This is the first global protein analysis of a microorganism capable of utilizing the carbon backbone of both polychlorinated dioxins and dibenzofurans as the sole source for carbon and energy.

Fluorene biodegradation potentials of Bacillus strains isolated from ...

African Journals Online (AJOL)

SAM

2014-04-02

Apr 2, 2014 ... They are found in fossil fuel and result from incom- ... are of concern because of their genotoxic effect for ... vehicle exhausts. ... fluorene degradation in the tropical African environment .... mg/kg) compared to APS (an asphalt-polluted soil along .... adapt and evolve necessary gene battery to degrade.

Draft Genome Sequence of Sphingomonas sp. Strain Sph1(2015), Isolated from a Fouled Membrane Filter Used To Produce Drinking Water.

Science.gov (United States)

de Vries, Hendrik J; Marshall, Ian P G; Schreiber, Lars; Plugge, Caroline M

2017-06-15

We report here the high-quality draft genome sequence of Sphingomonas sp. strain Sph1(2015), isolated from a fouled reverse osmosis membrane used for the production of high-quality drinking water. The draft sequence provides insights into the modus operandi of this strain to form biofilms on membrane surfaces. This knowledge offers tools to develop novel antifouling strategies. Copyright © 2017 de Vries et al.

Isolation from Agricultural Soil and Characterization of a Sphingomonas sp. Able To Mineralize the Phenylurea Herbicide Isoproturon

Science.gov (United States)

Sørensen, Sebastian R.; Ronen, Zeev; Aamand, Jens

2001-01-01

A soil bacterium (designated strain SRS2) able to metabolize the phenylurea herbicide isoproturon, 3-(4-isopropylphenyl)-1,1-dimethylurea (IPU), was isolated from a previously IPU-treated agricultural soil. Based on a partial analysis of the 16S rRNA gene and the cellular fatty acids, the strain was identified as a Sphingomonas sp. within the α-subdivision of the proteobacteria. Strain SRS2 was able to mineralize IPU when provided as a source of carbon, nitrogen, and energy. Supplementing the medium with a mixture of amino acids considerably enhanced IPU mineralization. Mineralization of IPU was accompanied by transient accumulation of the metabolites 3-(4-isopropylphenyl)-1-methylurea, 3-(4-isopropylphenyl)-urea, and 4-isopropyl-aniline identified by high-performance liquid chromatography analysis, thus indicating a metabolic pathway initiated by two successive N-demethylations, followed by cleavage of the urea side chain and finally by mineralization of the phenyl structure. Strain SRS2 also transformed the dimethylurea-substituted herbicides diuron and chlorotoluron, giving rise to as-yet-unidentified products. In addition, no degradation of the methoxy-methylurea-substituted herbicide linuron was observed. This report is the first characterization of a pure bacterial culture able to mineralize IPU. PMID:11722885

Decomposition of aqueous fluorene by γ-rays and product analysis

International Nuclear Information System (INIS)

Popov, P.; Getoff, Nikola

2004-01-01

Fluorene degradation was investigated in aqueous solution, saturated with air or N 2 O as a function of the absorbed radiation dose. The observed initial degradation yields (Gi values) are 2.41 and 1.04, respectively. In addition to these series, also studies were performed in media containing: 90% air and 10% N 2 O (Gi=1.1), 50% air and 50% N 2 O (Gi=0.9) and 10% air and 90% N 2 O (Gi=0.5). In all cases, as major degradation products 9-fluorenone and 9-fluorene carboxylic acid were found in addition to a mixture of aldehydes and carboxylic acids. Their yield depends on the starting pollutant concentration, absorbed radiation dose and oxygen content in the solution. For explanation of the results, probable reaction mechanisms are given

Convenient solvatochromic probes for the determination of solvent properties: {beta}-carotene and 2-chloro-7-nitro-9H-fluorene

Energy Technology Data Exchange (ETDEWEB)

Seoud, Omar A. El; Pires, Paulo A.R.; Loffredo, Carina; Imran, Muhammad; Pulcini, Paolo D.; Correa, Michelle F.; Mustafa, Rizwana, E-mail: elseoud@iq.usp.br [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Quimica

2013-07-15

Solvent dipolarity/polarizability (SDP) has been previously calculated from the UV-Vis spectra of 2-(N,N-dimethylamino)-7-nitro-9H-fluorene and 2-fluoro-7-nitro-9H- fluorene. Based on theoretical calculations (23 solvents) and experimental data (56 solvents), it is shown that 2-chloro-7-nitro-9H-fluorene (commercially available) can be conveniently employed for the calculation of this property, instead of its 2-fluoro-7-nitro counterpart. The splitting of SDP into its components (solvent dipolarity (SD) and polarizability (SP)) requires the use of a synthetic polyene compound whose synthesis is laborious, involving 15 steps. Our research group has recently shown that the natural dye {beta}-carotene can be conveniently employed for the determination of SP, allowing the calculation of SD. Using these solvatochromic probes, SDP, SP and SD for a series of 1-bromo alkanes were calculated. For several homologous series, the dependence of solvent SDP (SD and SP for one series) on the number of carbon atoms in the 1-alkyl- or acyl-group was calculated and discussed. (author)

Metabolism of nitrodiphenyl ether herbicides by dioxin-degrading bacterium Sphingomonas wittichii RW1.

Science.gov (United States)

Keum, Young Soo; Lee, Young Ju; Kim, Jeong-Han

2008-10-08

Nitrodiphenyl ether herbicides, including chlomethoxyfen, nitrofen, and oxyfluorfen are potent herbicides. Some metabolites and parent compounds are considered as possible mutagens and endocrine disruptors. Both properties pose serious hygienic and environmental risks. Sphingomonas wittichii RW1 is a well-known degrader of polychlorinated dibenzo- p-dioxins, dibenzofurans, and diphenyl ethers. However, no detailed research of its metabolic activity has been performed against pesticides with a diphenyl ether scaffold. In this study, we report S. wittichii RW1 as a very potent diphenyl ether herbicide-metabolizing bacterium with broad substrate specificity. The structures of metabolites were determined by instrumental analysis and synthetic standards. Most pesticides were rapidly removed from the culture medium in the order of nitrofen > oxyfluorfen > chlomethoxyfen. In general, herbicides were degraded through the initial reduction and N-acetylation of nitro groups, followed by ether bond cleavage. Relatively low concentrations of phenolic and catecholic metabolites throughout the study suggested that these metabolites were rapidly metabolized and incorporated into primary metabolism. These results indicate that strain RW1 has very versatile metabolic activities over a wide range of environmental contaminants.

Fluoren-9-one oxime

Directory of Open Access Journals (Sweden)

Bernhard Bugenhagen

2014-03-01

Full Text Available In the title molecule, C13H9NO, the fluorene system and the oxime group non-H atoms are essentially coplanar, with a maximum deviation from the fluorene mean plane of 0.079 (2 Å for the oxime O atom. A short intramolecular C—H...O generates an S(6 ring. In the crystal, molecules related by a twofold screw axis are connected by O—H...N hydrogen bonds, forming [100] chains Within these chains, molecules related by a unit translation along [100] show π–π stacking interactions between their fluorene ring systems with an interplanar distance of 3.347 (2 Å. The dihedral angle between the fluorene units of adjacent molecules along the helix is 88.40 (2°. There is a short C—H...π contact between the fluorene groups belonging to neighbouring chains.

Novel soluble fluorene-thienothiadiazole and fluorene-carbazole copolymers for optoelectronics

Czech Academy of Sciences Publication Activity Database

Cimrová, Věra; Kmínek, Ivan; Výprachtický, Drahomír

2010-01-01

Roč. 295, č. 1 (2010), s. 65-70 ISSN 1022-1360. [Prague Meetings on Macromolecules /73./ New Frontiers in Macromolecular Science: From Macromolecular Concepts of Living Matter to Polymers for Better Quality of Life. Prague, 05.07.2009-09.07.2009] R&D Projects: GA MŠk(CZ) 1M06031; GA AV ČR IAA4050409 Institutional research plan: CEZ:AV0Z40500505 Keywords : fluorene – thienothiadiazole copolymers * photovoltaics * fluorene-carbazole copolymers Subject RIV: JA - Electronics ; Optoelectronics , Electrical Engineering

Bioremediation of polycyclic aromatic hydrocarbon (PAH compounds: (acenaphthene and fluorene in water using indigenous bacterial species isolated from the Diep and Plankenburg rivers, Western Cape, South Africa

Directory of Open Access Journals (Sweden)

Oluwadara Oluwaseun Alegbeleye

Full Text Available Abstract This study was conducted to investigate the occurrence of PAH degrading microorganisms in two river systems in the Western Cape, South Africa and their ability to degrade two PAH compounds: acenaphthene and fluorene. A total of 19 bacterial isolates were obtained from the Diep and Plankenburg rivers among which four were identified as acenaphthene and fluorene degrading isolates. In simulated batch scale experiments, the optimum temperature for efficient degradation of both compounds was determined in a shaking incubator after 14 days, testing at 25 °C, 30 °C, 35 °C, 37 °C, 38 °C, 40 °C and 45 °C followed by experiments in a Stirred Tank Bioreactor using optimum temperature profiles from the batch experiment results. All experiments were run without the addition of supplements, bulking agents, biosurfactants or any other form of biostimulants. Results showed that Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila efficiently degraded both compounds at 37 °C, 37 °C, 30 °C and 35 °C respectively. The degradation of fluorene was more efficient and rapid compared to that of acenaphthene and degradation at Stirred Tank Bioreactor scale was more efficient for all treatments. Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila degraded a mean total of 98.60%, 95.70%, 90.20% and 99.90% acenaphthene, respectively and 99.90%, 97.90%, 98.40% and 99.50% fluorene, respectively. The PAH degrading microorganisms isolated during this study significantly reduced the concentrations of acenaphthene and fluorene and may be used on a larger, commercial scale to bioremediate PAH contaminated river systems.

Purification, characterization of Chondroitinase ABC from Sphingomonas paucimobilis and in vitro cardiocytoprotection of the enzymatically degraded CS-A.

Science.gov (United States)

Fu, Jingyun; Jiang, Zhiwen; Chang, Jing; Han, Baoqin; Liu, Wanshun; Peng, Yanfei

2018-04-24

An extracellular chondroitinase ABC (ChSase ABC) produced by Sphingomonas paucimobilis was purified to homogeneity through ammonium sulfate precipitation, DEAE-Sepharose Fast Flow and Sephadex G-100 chromatography. The molecular weight was 82.3 kDa. It showed specific lyase activity toward chondroitin sulfate A (CS-A), CS-B, CS-C and hyaluronan (HA). Using CS-A as substrate, the specific activity was 98.04 U/mg, the maximal reaction rate (V max ) and Michaelis-Menten constant (K m ) were 0.49 μmol/min/ml and 0.79 mg/ml, respectively. Highest activity was obtained at pH 6.5 and 40 °C, and Hg 2+ could strongly inhibit the enzyme activity. Mass spectrometry analysis indicated CS-A was degraded to unsaturated disaccharides by ChSase ABC. In vitro cytotoxic tests showed that CS-A oligosaccharide at the concentration of 50 and 100 μg/ml could promote the proliferation of normal H9c2 myocardial cells, decrease the damage induced by isoproterenol (ISO) and accelerate the recovery of cells injured by ISO. These findings suggested that ChSase ABC from Sphingomonas paucimobilis could be a promising tool for the structural analysis and bioactive oligosaccharide preparation of glucosaminoglycans. Copyright © 2018 Elsevier B.V. All rights reserved.

Degradation of naphthalene and fluorene by radiolysis using accelerated electrons; Degradacion de naftaleno y fluoreno por radiolisis empleando electrones acelerados

Energy Technology Data Exchange (ETDEWEB)

Flores de Jesus, I

2003-07-01

The volume of the dangerous wastes in global level is causing the poisoning of planet and all of the ecosystems, degrading the life level of millions of humans and causing serious problems in the public health. Since a years ago the volumes of organic effluents generated by the few industry and small populations were so tiny that a natural debugger process in a time and space delimited, acquiring again their natural characteristics and they could be used again. Nowadays these wastes are so numerous and precise in some cases that the capacity of natural purification in the receiving channel is not enough, in addition to the difficulty to treat them in conventional processes, this leads to the decrease in the water's quality making impossible its future use and causing with this a serious ecological problem. This fact has motivated the development of measures that tend to the conservation of the environment and in consequence, the development of debugger technologies with no generation of sub products that often are more dangerous than the originals, due to the previous thing, the treatment by means of radiation of the water is impelled since is a method that allows to degrade or to eliminate in simultaneous form pathogenic microorganisms and organic substances. The radiation by means of electrons beams is a method of advanced treatment who allows to degrade organic compounds, transforming them in compounds with less molecular weight, and in the best of the cases until its oxidation to carbon dioxide and water. In the present thesis the objective is the study of naphthalene and fluorene degradation by means of radiation with electron beams, establishing the operating conditions of the accelerator of Pelletron type. This research is supported by the Instituto Nacional de Investigaciones Nucleares, of a joint way with a series of antecedents in this subject, established in previous research with respect to the treatment of residual waters in a great scale, giving

Degradation of naphthalene and fluorene by radiolysis using accelerated electrons; Degradacion de naftaleno y fluoreno por radiolisis empleando electrones acelerados

Energy Technology Data Exchange (ETDEWEB)

Flores de Jesus, I

2003-07-01

The volume of the dangerous wastes in global level is causing the poisoning of planet and all of the ecosystems, degrading the life level of millions of humans and causing serious problems in the public health. Since a years ago the volumes of organic effluents generated by the few industry and small populations were so tiny that a natural debugger process in a time and space delimited, acquiring again their natural characteristics and they could be used again. Nowadays these wastes are so numerous and precise in some cases that the capacity of natural purification in the receiving channel is not enough, in addition to the difficulty to treat them in conventional processes, this leads to the decrease in the water's quality making impossible its future use and causing with this a serious ecological problem. This fact has motivated the development of measures that tend to the conservation of the environment and in consequence, the development of debugger technologies with no generation of sub products that often are more dangerous than the originals, due to the previous thing, the treatment by means of radiation of the water is impelled since is a method that allows to degrade or to eliminate in simultaneous form pathogenic microorganisms and organic substances. The radiation by means of electrons beams is a method of advanced treatment who allows to degrade organic compounds, transforming them in compounds with less molecular weight, and in the best of the cases until its oxidation to carbon dioxide and water. In the present thesis the objective is the study of naphthalene and fluorene degradation by means of radiation with electron beams, establishing the operating conditions of the accelerator of Pelletron type. This research is supported by the Instituto Nacional de Investigaciones Nucleares, of a joint way with a series of antecedents in this subject, established in previous research with respect to the treatment of residual waters in a great scale, giving

Biodegradation Ability and Catabolic Genes of Petroleum-Degrading Sphingomonas koreensis Strain ASU-06 Isolated from Egyptian Oily Soil

Directory of Open Access Journals (Sweden)

Abd El-Latif Hesham

2014-01-01

Full Text Available Polycyclic aromatic hydrocarbons (PAHs are serious pollutants and health hazards. In this study, 15 PAHs-degrading bacteria were isolated from Egyptian oily soil. Among them, one Gram-negative strain (ASU-06 was selected and biodegradation ability and initial catabolic genes of petroleum compounds were investigated. Comparison of 16S rRNA gene sequence of strain ASU-06 to published sequences in GenBank database as well as phylogenetic analysis identified ASU-06 as Sphingomonas koreensis. Strain ASU-06 degraded 100, 99, 98, and 92.7% of 100 mg/L naphthalene, phenanthrene, anthracene, and pyrene within 15 days, respectively. When these PAHs present in a mixed form, the enhancement phenomenon appeared, particularly in the degradation of pyrene, whereas the degradation rate was 98.6% within the period. This is the first report showing the degradation of different PAHs by this species. PCR experiments with specific primers for catabolic genes alkB, alkB1, nahAc, C12O, and C23O suggested that ASU-06 might possess genes for aliphatic and PAHs degradation, while PAH-RHDαGP gene was not detected. Production of biosurfactants and increasing cell-surface hydrophobicity were investigated. GC/MS analysis of intermediate metabolites of studied PAHs concluded that this strain utilized these compounds via two main pathways, and phthalate was the major constant product that appeared in each day of the degradation period.

Bioremediation of polycyclic aromatic hydrocarbon (PAH) compounds: (acenaphthene and fluorene) in water using indigenous bacterial species isolated from the Diep and Plankenburg rivers, Western Cape, South Africa.

Science.gov (United States)

Alegbeleye, Oluwadara Oluwaseun; Opeolu, Beatrice Olutoyin; Jackson, Vanessa

This study was conducted to investigate the occurrence of PAH degrading microorganisms in two river systems in the Western Cape, South Africa and their ability to degrade two PAH compounds: acenaphthene and fluorene. A total of 19 bacterial isolates were obtained from the Diep and Plankenburg rivers among which four were identified as acenaphthene and fluorene degrading isolates. In simulated batch scale experiments, the optimum temperature for efficient degradation of both compounds was determined in a shaking incubator after 14 days, testing at 25°C, 30°C, 35°C, 37°C, 38°C, 40°C and 45°C followed by experiments in a Stirred Tank Bioreactor using optimum temperature profiles from the batch experiment results. All experiments were run without the addition of supplements, bulking agents, biosurfactants or any other form of biostimulants. Results showed that Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila efficiently degraded both compounds at 37°C, 37°C, 30°C and 35°C respectively. The degradation of fluorene was more efficient and rapid compared to that of acenaphthene and degradation at Stirred Tank Bioreactor scale was more efficient for all treatments. Raoultella ornithinolytica, Serratia marcescens, Bacillus megaterium and Aeromonas hydrophila degraded a mean total of 98.60%, 95.70%, 90.20% and 99.90% acenaphthene, respectively and 99.90%, 97.90%, 98.40% and 99.50% fluorene, respectively. The PAH degrading microorganisms isolated during this study significantly reduced the concentrations of acenaphthene and fluorene and may be used on a larger, commercial scale to bioremediate PAH contaminated river systems. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Different nitrogen sources change the transcriptome of welan gum-producing strain Sphingomonas sp. ATCC 31555.

Science.gov (United States)

Xu, Xiaopeng; Nie, Zuoming; Zheng, Zhiyong; Zhu, Li; Zhang, Hongtao; Zhan, Xiaobei

2017-09-01

To reveal effects of different nitrogen sources on the expressions and functions of genes in Sphingomonas sp. ATCC 31555, it was cultivated in medium containing inorganic nitrogen (IN), organic nitrogen (ON), or inorganic-organic combined nitrogen (CN). Welan gum production and bacterial biomass were determined, and RNA sequencing (RNA-seq) was performed. Differentially expressed genes (DEGs) between the different ATCC 31555 groups were identified, and their functions were analyzed. Welan gum production and bacterial biomass were significantly higher in the ON and CN groups compared with those in the IN group. RNA-seq produced 660 unigenes, among which 488, 731, and 844 DEGs were identified between the IN vs. ON, IN vs. CN, and ON vs. CN groups, respectively. All the DEGs were related significantly to metabolic process and signal transduction. DEGs between the IN vs. CN and ON vs. CN groups were potentially associated with bacterial chemotaxis. Real-time PCR confirmed the expressions of selected DEGs. Organic nitrogen led to higher bacterial biomass and welan gum production than inorganic nitrogen, which might reflect differences in gene expression associated with metabolic process, signal transduction, and bacterial chemotaxis induced by different nitrogen sources.

Degradation of lignin β-aryl ether units in Arabidopsis thaliana expressing LigD, LigF and LigG from Sphingomonas paucimobilis SYK-6

DEFF Research Database (Denmark)

Mnich, Ewelina; Vanholme, Ruben; Oyarce, Paula

2017-01-01

Lignin is a major polymer in the secondary plant cell wall and composed of hydrophobic interlinked hydroxyphenylpropanoid units. The presence of lignin hampers conversion of plant biomass into biofuels; plants with modified lignin are therefore being investigated for increased digestibility....... The bacterium Sphingomonas paucimobilis produces lignin-degrading enzymes including LigD, LigF and LigG involved in cleaving the most abundant lignin inter-unit linkage, the β-aryl ether bond. In this study, we expressed the LigD, LigF and LigG (LigDFG) genes in Arabidopsis thaliana to introduce post...

The synthesis of mono- and diacetyl-9H-fluorenes. Reactivity and selectivity in the Lewis acid catalyzed Friedel-Crafts acetylation of 9H-fluorene

DEFF Research Database (Denmark)

Titinchi, Salam J. J.; Kamounah, Fadhil S.; Abbo, Hanna S.

2008-01-01

Friedel-Crafts acetylation of 9H-fluorene is an effective route for the preparation of mono- and diacetyl-9H-fluorenes. Using acetylchloride as the reagent and aluminum chloride as the Lewis acid catalyst the effect of the solvent polarity, the temperature, the reaction time and the mode of addit......Friedel-Crafts acetylation of 9H-fluorene is an effective route for the preparation of mono- and diacetyl-9H-fluorenes. Using acetylchloride as the reagent and aluminum chloride as the Lewis acid catalyst the effect of the solvent polarity, the temperature, the reaction time and the mode......,7-diacetyl-9H-fluorene was obtained in 5-11 % yield when carbon disulfide was used as the solvent. Acetylation of 9H-fluorene in dichloroethane and carbon disulfide, using an excess of acetyl chloride and aluminum chloride at reflux temperature, gives 2,7-diacetyl-9H-fluorene exclusively in high yields (> 97...

Cdc20 mediates D-box-dependent degradation of Sp100

International Nuclear Information System (INIS)

Wang, Ran; Li, Ke-min; Zhou, Cai-hong; Xue, Jing-lun; Ji, Chao-neng; Chen, Jin-zhong

2011-01-01

Highlights: ► Cdc20 is a co-activator of APC/C complex. ► Cdc20 recruits Sp100 and mediates its degradation. ► The D-box of Sp100 is required for Cdc20-mediated degradation. ► Sp100 expresses consistently at both the mRNA and protein levels in cell cycle. -- Abstract: Cdc20 is a co-activator of the anaphase-promoting complex/cyclosome (APC/C complex), which recruits substrates at particular phases of the cell cycle and mediates their degradation. Sp100 is a PML-NB scaffold protein, which localizes to nuclear particles during interphase and disperses from them during mitosis, participates in viral resistance, transcriptional regulation, and apoptosis. However, its metabolism during the cell cycle has not yet been fully characterized. We found a putative D-box in Sp100 using the Eukaryotic Linear Motif (ELM) predictor database. The putative D-box of Sp100 was verified by mutational analysis. Overexpression of Cdc20 resulted in decreased levels of both endogenous Sp100 protein and overexpressed Sp100 mRNA in HEK 293 cells. Only an overexpressed D-box deletion mutant of Sp100 accumulated in HEK293 cells that also overexpressed Cdc20. Cdc20 knockdown by cdc20 specific siRNA resulted in increased Sp100 protein levels in cells. Furthermore, we discovered that the Cdc20 mediated degradation of Sp100 is diminished by the proteasome inhibitor MG132, which suggests that the ubiquitination pathway is involved in this process. However, unlike the other Cdc20 substrates, which display oscillating protein levels, the level of Sp100 protein remains constant throughout the cell cycle. Additionally, both overexpression and knockdown of endogenous Sp100 had no effect on the cell cycle. Our results suggested that sp100 is a novel substrate of Cdc20 and it is degraded by the ubiquitination pathway. The intact D-box of Sp100 was necessary for this process. These findings expand our knowledge of both Sp100 and Cdc20 as well as their role in ubiquitination.

Dynamics and role of sphingomonas/mycobacterium populations during bio-remediation of weathered PAH-contaminated soils

International Nuclear Information System (INIS)

Bastiaens, L.; Ryngaert, A.; Leys, N.; Van Houtven, D.; Gemoets, J.; Goethals, L.; Springael, D.

2005-01-01

Polycyclic Aromatic Hydrocarbons (PAHs) are major soil pollutants in many industrialized countries. During the last decades, a diversity of PAH-degrading micro-organisms has been isolated, suggesting possibilities for bio-remediation. However, biodegradation of PAHs in contaminated soils is not always successful. The low bio-availability of the PAHs is the major problem, especially in weathered soils. In these soils a tightly sorbed PAH-fraction is present which is in general hardly accessible for microorganisms. In order to bio-remedy PAHs also in weathered soils, stimulation of bacteria which have special strategies to access sorbed organics may be a solution. Sphingomonas and Mycobacterium strains may represent such bacteria as (I) they are often isolated as PAH degraders, (II) they are ubiquitously present in PAH-contaminated soils, and (III) they display features which might promote bioavailability. Lab- and pilot-scale experiments were set up in order (A) to study the dynamics of indigenous Sphingomonas and Mycobacterium populations during bio-remediation, and (B) to evaluate their role in the biodegradation of the less bio-available PAH-fraction during treatment of an historic PAH polluted soil. The soil was treated under natural soil moisture conditions and slurry conditions. The experimental set-ups ranged from 2 g lab-scale test to pilot experiments in 1 ton bio-piles and dry solid reactors (50 kg 70% dry matter soil). Different additives were evaluated for stimulation of the Sphingomonas and Mycobacterium population as a strategy to improve bio-remediation of PAHs. The evolution of this microbial population was followed using culture-independent general and genus-specific PCR-based detection methods targeting the 16S rRNA genes of the eu-bacterial community, Mycobacterium or the Sphingomonas populations, respectively. During the different bio-remediation experiments that were conducted, the Mycobacterium population remained very stable, only minor

Dynamics and role of sphingomonas/mycobacterium populations during bio-remediation of weathered PAH-contaminated soils

Energy Technology Data Exchange (ETDEWEB)

Bastiaens, L.; Ryngaert, A.; Leys, N.; Van Houtven, D.; Gemoets, J. [Flemish Institute for Technological Research-Vito, Mol (Belgium); Goethals, L. [ENVISAN, Aalst, (Belgium); Springael, D. [Catholic University of Leuven-KUL, Leuven (Belgium)

2005-07-01

Polycyclic Aromatic Hydrocarbons (PAHs) are major soil pollutants in many industrialized countries. During the last decades, a diversity of PAH-degrading micro-organisms has been isolated, suggesting possibilities for bio-remediation. However, biodegradation of PAHs in contaminated soils is not always successful. The low bio-availability of the PAHs is the major problem, especially in weathered soils. In these soils a tightly sorbed PAH-fraction is present which is in general hardly accessible for microorganisms. In order to bio-remedy PAHs also in weathered soils, stimulation of bacteria which have special strategies to access sorbed organics may be a solution. Sphingomonas and Mycobacterium strains may represent such bacteria as (I) they are often isolated as PAH degraders, (II) they are ubiquitously present in PAH-contaminated soils, and (III) they display features which might promote bioavailability. Lab- and pilot-scale experiments were set up in order (A) to study the dynamics of indigenous Sphingomonas and Mycobacterium populations during bio-remediation, and (B) to evaluate their role in the biodegradation of the less bio-available PAH-fraction during treatment of an historic PAH polluted soil. The soil was treated under natural soil moisture conditions and slurry conditions. The experimental set-ups ranged from 2 g lab-scale test to pilot experiments in 1 ton bio-piles and dry solid reactors (50 kg 70% dry matter soil). Different additives were evaluated for stimulation of the Sphingomonas and Mycobacterium population as a strategy to improve bio-remediation of PAHs. The evolution of this microbial population was followed using culture-independent general and genus-specific PCR-based detection methods targeting the 16S rRNA genes of the eu-bacterial community, Mycobacterium or the Sphingomonas populations, respectively. During the different bio-remediation experiments that were conducted, the Mycobacterium population remained very stable, only minor

Cdc20 mediates D-box-dependent degradation of Sp100

Energy Technology Data Exchange (ETDEWEB)

Wang, Ran; Li, Ke-min; Zhou, Cai-hong; Xue, Jing-lun [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai (China); Ji, Chao-neng, E-mail: Chnji@fudan.edu.cn [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai (China); Chen, Jin-zhong, E-mail: kingbellchen@fudan.edu.cn [State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai (China)

2011-12-02

Highlights: Black-Right-Pointing-Pointer Cdc20 is a co-activator of APC/C complex. Black-Right-Pointing-Pointer Cdc20 recruits Sp100 and mediates its degradation. Black-Right-Pointing-Pointer The D-box of Sp100 is required for Cdc20-mediated degradation. Black-Right-Pointing-Pointer Sp100 expresses consistently at both the mRNA and protein levels in cell cycle. -- Abstract: Cdc20 is a co-activator of the anaphase-promoting complex/cyclosome (APC/C complex), which recruits substrates at particular phases of the cell cycle and mediates their degradation. Sp100 is a PML-NB scaffold protein, which localizes to nuclear particles during interphase and disperses from them during mitosis, participates in viral resistance, transcriptional regulation, and apoptosis. However, its metabolism during the cell cycle has not yet been fully characterized. We found a putative D-box in Sp100 using the Eukaryotic Linear Motif (ELM) predictor database. The putative D-box of Sp100 was verified by mutational analysis. Overexpression of Cdc20 resulted in decreased levels of both endogenous Sp100 protein and overexpressed Sp100 mRNA in HEK 293 cells. Only an overexpressed D-box deletion mutant of Sp100 accumulated in HEK293 cells that also overexpressed Cdc20. Cdc20 knockdown by cdc20 specific siRNA resulted in increased Sp100 protein levels in cells. Furthermore, we discovered that the Cdc20 mediated degradation of Sp100 is diminished by the proteasome inhibitor MG132, which suggests that the ubiquitination pathway is involved in this process. However, unlike the other Cdc20 substrates, which display oscillating protein levels, the level of Sp100 protein remains constant throughout the cell cycle. Additionally, both overexpression and knockdown of endogenous Sp100 had no effect on the cell cycle. Our results suggested that sp100 is a novel substrate of Cdc20 and it is degraded by the ubiquitination pathway. The intact D-box of Sp100 was necessary for this process. These findings expand

A combined experimental and computational thermodynamic study of fluorene-9-methanol and fluorene-9-carboxylic acid

International Nuclear Information System (INIS)

Oliveira, Juliana A.S.A.; Calvinho, Maria M.; Notario, R.; Monte, Manuel J.S.; Ribeiro da Silva, Maria D.M.C.

2013-01-01

Highlights: • A thermodynamic study of two fluorene derivatives is presented. • Vapour pressures and energies of combustion were measured. • Enthalpy, entropy and Gibbs energy of sublimation were derived. • Enthalpy and Gibbs energy of formation in crystal and gas phases were calculated. • Gas phase enthalpy of formation was also estimated by quantum chemical calculations. -- Abstract: This work reports an experimental and computational thermodynamic study performed on two 9-fluorene derivatives: fluorene-9-methanol and fluorene-9-carboxylic acid. The standard (p o = 0.1 MPa) molar enthalpies of formation in the crystalline phase of these compounds were derived from the standard molar energies of combustion, in oxygen, at T = 298.15 K, measured by static bomb combustion calorimetry. A static method, based on a capacitance diaphragm gauge, and a Knudsen effusion method were used to perform the vapour pressure study of the referred compounds, yielding accurate determination of the standard molar enthalpies and entropies of sublimation and vaporisation. For fluorene-9-carboxylic acid, the enthalpy of sublimation was also determined using Calvet microcalorimetry. The enthalpy of fusion of both compounds was derived indirectly from vapour pressure results and directly from DSC experiments. Combining the thermodynamic parameters of the compounds studied, the standard Gibbs energy of formation in crystalline and gaseous phases were derived as well as the standard molar enthalpy of formation in the gaseous phase. A theoretical study at the G3 and G4 levels has been carried out, and the calculated enthalpies of formation have been compared with the experimental values

Reclassification of rhizosphere bacteria including strains causing corky root of lettuce and proposal of Rhizorhapis suberifaciens gen. nov., comb. nov., Sphingobium mellinum sp. nov., Sphingobium xanthum sp. nov. and Rhizorhabdus argentea gen. nov., sp. nov.

Science.gov (United States)

Francis, Isolde M; Jochimsen, Kenneth N; De Vos, Paul; van Bruggen, Ariena H C

2014-04-01

The genus Rhizorhapis gen. nov. (to replace the illegitimate genus name Rhizomonas) is proposed for strains of Gram-negative bacteria causing corky root of lettuce, a widespread and important lettuce disease worldwide. Only one species of the genus Rhizomonas was described, Rhizomonas suberifaciens, which was subsequently reclassified as Sphingomonas suberifaciens based on 16S rRNA gene sequences and the presence of sphingoglycolipid in the cell envelope. However, the genus Sphingomonas is so diverse that further reclassification was deemed necessary. Twenty new Rhizorhapis gen. nov.- and Sphingomonas-like isolates were obtained from lettuce or sow thistle roots, or from soil using lettuce seedlings as bait. These and previously reported isolates were characterized in a polyphasic study including 16S rRNA gene sequencing, DNA-DNA hybridization, DNA G+C content, whole-cell fatty acid composition, morphology, substrate oxidation, temperature and pH sensitivity, and pathogenicity to lettuce. The isolates causing lettuce corky root belonged to the genera Rhizorhapis gen. nov., Sphingobium, Sphingopyxis and Rhizorhabdus gen. nov. More specifically, we propose to reclassify Rhizomonas suberifaciens as Rhizorhapis suberifaciens gen. nov., comb. nov. (type strain, CA1(T) = LMG 17323(T) = ATCC 49355(T)), and also propose the novel species Sphingobium xanthum sp. nov., Sphingobium mellinum sp. nov. and Rhizorhabdus argentea gen. nov., sp. nov. with the type strains NL9(T) ( = LMG 12560(T) = ATCC 51296(T)), WI4(T) ( = LMG 11032(T) = ATCC 51292(T)) and SP1(T) ( = LMG 12581(T) = ATCC 51289(T)), respectively. Several strains isolated from lettuce roots belonged to the genus Sphingomonas, but none of them were pathogenic.

Fluorene: An extended experimental thermodynamic study

International Nuclear Information System (INIS)

Monte, Manuel J.S.; Pinto, Sónia P.; Lobo Ferreira, Ana I.M.C.; Amaral, Luísa M.P.F.; Freitas, Vera L.S.; Ribeiro da Silva, Maria D.M.C.

2012-01-01

Highlights: ► Experimental results of an extended thermodynamic study on fluorene are presented. ► Enthalpy of combustion and vapor pressures of liquid and crystalline phase were measured. ► Enthalpy of sublimation was derived from three different experimental methods. ► New values of enthalpies of sublimation and of formation of fluorene are recommended. - Abstract: This work reports new experimental thermodynamic results on fluorene. Vapor pressures of both crystalline and liquid phases were measured using a pressure gauge (capacitance diaphragm manometer) and Knudsen effusion methods over a wide temperature range (292.20 to 412.16) K yielding accurate determination of enthalpy and entropy of sublimation and of vaporization. The enthalpy of sublimation was also determined using Calvet microcalorimetry. The enthalpy of fusion was derived from vapor pressure results and from d.s.c. experiments. Static bomb calorimetry was used to determine the enthalpy of combustion of fluorene from which the standard enthalpy of formation in the crystalline phase was calculated. The enthalpy of formation in the gaseous phase was calculated combining the result derived for the crystalline phase with the enthalpy of sublimation.

Production and Rheological Properties of Welan Gum Produced by Sphingomonas sp. ATCC 31555 with Different Nitrogen Sources.

Science.gov (United States)

Xu, Xiaopeng; Nie, Zuoming; Zheng, Zhiyong; Zhu, Li; Zhan, Xiaobei

2017-01-01

This study aimed to investigate the effect of nitrogen sources on the production and rheological properties of welan gum produced by Sphingomonas sp. ATCC 31555. Six different nitrogen sources were used for ATCC 31555 fermentation, and 2 of these were further analyzed due to their more positive influence on welan gum production and bacterial biomass. Bacterial biomass, welan gum yield, welan viscosity, molecular weight, monosaccharide composition, acyl content, and welan structure were analyzed. Welan gum production and the biomass concentration of ATCC 31555 were higher in media containing NaNO3 and beef extract. Welan viscosity decreased at higher temperatures of 30-90°C, and it increased with a higher welan concentration. In the media containing NaNO3 (3 g·L-1), welan viscosity was higher at 30-70°C and a welan solution concentration of 6-10 g·L-1. With a reduced NaNO3 concentration, the molecular weight of welan gum and the molar ratio of mannose decreased, but the molar ratio of glucuronic acid increased. With different nitrogen sources, the acetyl content of welan gum differed but its structure was similar. NaNO3 and beef extract facilitated welan production. A reduced NaNO3 concentration promoted welan viscosity. © 2017 S. Karger AG, Basel.

Characterization of the novel dimethyl sulfide-degrading bacterium Alcaligenes sp. SY1 and its biochemical degradation pathway

Energy Technology Data Exchange (ETDEWEB)

Sun, Yiming; Qiu, Jiguo; Chen, Dongzhi; Ye, Jiexu; Chen, Jianmeng, E-mail: jchen@zjut.edu.cn

2016-03-05

Highlights: • A novel efficient DMS-degrading bacterium Alcaligenes sp. SY1 was identified. • A RSM was applied to optimize incubation condition of Alcaligenes sp. SY1. • SIP was applied as C{sup 13} labelled DMS to trace intermediates during DMS degradation. • Kinetics of DMS degradation via batch experiment was revealed. • Carbon and sulfur balance were analyzed during DMS degradation process. - Abstract: Recently, the biodegradation of volatile organic sulfur compounds (VOSCs) has become a burgeoning field, with a growing focus on the reduction of VOSCs. The reduction of VOSCs encompasses both organic emission control and odor control. Herein, Alcaligenes sp. SY1 was isolated from active sludge and found to utilize dimethyl sulfide (DMS) as a growth substrate in a mineral salt medium. Response surface methodology (RSM) analysis was applied to optimize the incubation conditions. The following conditions for optimal degradation were identified: temperature 27.03 °C; pH 7.80; inoculum salinity 0.84%; and initial DMS concentration 1585.39 μM. Under these conditions, approximately 99% of the DMS was degraded within 30 h of incubation. Two metabolic compounds were detected and identified by gas chromatography–mass spectrometry (GC–MS): dimethyl disulfide (DMDS) and dimethyl trisulfide (DMTS). The DMS degradation kinetics for different concentrations were evaluated using the Haldane–Andrews model and the pseudo first-order model. The maximum specific growth rate and degradation rate of Alcaligenes sp. SY1 were 0.17 h{sup −1} and 0.63 gs gx{sup −1} h{sup −1}. A possible degradation pathway is proposed, and the results suggest that Alcaligenes sp. SY1 has the potential to control odor emissions under aerobic conditions.

Isolation of Inositol Hexaphosphate (IHP)-Degrading Bacteria from Arbuscular Mycorrhizal Fungal Hyphal Compartments Using a Modified Baiting Method Involving Alginate Beads Containing IHP

Science.gov (United States)

Hara, Shintaro; Saito, Masanori

2016-01-01

Phytate (inositol hexaphosphate; IHP)-degrading microbes have been suggested to contribute to arbuscular mycorrhizal fungi (AMF)-mediated P transfer from IHP to plants; however, no IHP degrader involved in AMF-mediated P transfer has been isolated to date. We herein report the isolation of IHP-degrading bacteria using a modified baiting method. We applied alginate beads as carriers of IHP powder, and used them as recoverable IHP in the AM fungal compartment of plant cultivation experiments. P transfer from IHP in alginate beads via AMF was confirmed, and extracted DNA from alginate beads was analyzed by denaturing gradient gel electrophoresis targeting the 16S rRNA gene and a clone library method for the beta-propeller phytase (BPP) gene. The diversities of the 16S rRNA and BPP genes of microbes growing on IHP beads were simple and those of Sphingomonas spp. and Caulobacter spp. dominated. A total of 187 IHP-utilizing bacteria were isolated and identified, and they were consistent with the results of DNA analysis. Furthermore, some isolated Sphingomonas spp. and Caulobacter sp. showed IHP-degrading activity. Therefore, we successfully isolated dominant IHP-degrading bacteria from IHP in an AMF hyphal compartment. These strains may contribute to P transfer from IHP via AMF. PMID:27383681

Fluorene transformation by bacteria of the genus Rhodococcus

NARCIS (Netherlands)

Finkelstein, Z.I.; Baskunov, B.P.; Golovlev, E.L.; Vervoort, J.J.M.; Rietjens, I.M.C.M.; Baboshin, M.A.; Golovleva, L.A.

2003-01-01

Of the four investigated Rhodococcus strains (R. rhodochrous172, R. opacus 4a and 557, and R. rhodnii 135), the first three strains were found to be able to completely transform fluorene when it was present in the medium as the sole source of carbon at a concentration of 12¿25 mg/l. At a fluorene

Supramolecular fluorene based materials

NARCIS (Netherlands)

Abbel, R.J.

2008-01-01

This thesis describes the use of noncovalent interactions in order to manipulate and control the self-assembly and morphology of electroactive fluorene-based materials. The supramolecular arrangement of p-conjugated polymers and oligomers can strongly influence their electronic and photophysical

Interactions among buffelgrass, phenanthrene and phenanthrene-degrading bacteria in gnotobiotic microcosms.

Science.gov (United States)

Robert, Francoise M; Sun, Wenhao H; Toma, Marisa; Jones, Ryan K; Tang, Chung-Shih

2008-07-15

An experiment was undertaken in gnotobiotic microcosms to determine the role of buffelgrass (Cenchrus ciliaris) and a phenanthrene-degrading bacterium (strain PM600) in the degradation of phenanthrene. The Gram-negative bacterium was identified as a Sphingomonas sp. by 16S rRNA gene sequence analysis and as S. paucimobilis by biochemical tests (API 20 NE strips). Its yellow pigment corresponded to nostoxanthin and its cellular fatty acids were typical of the genus Sphingomonas. Moreover, it was devoid of lipopolysaccharides. Strain PM600 was tested for growth on mineral medium supplemented with No. 2 diesel, hexadecane, mineral oil, pristane, phenanthrene, and pyrene as single carbon sources. It was capable of utilizing phenanthrene only. In the gnotobiotic microcosms silica sand was either or not supplemented with 150 mg of phenanthrene kg(-1) sand, inoculated with strain PM600, and planted to sterile young seedlings of buffelgrass. After 28 days, 67% of the reduction of the phenanthrene concentration was assigned to degradation by the bacterium and ca. 20% to abiotic factors. No statistically significant effect of the young buffelgrass was found. In the absence of phenanthrene, the bacterial population significantly increased in the rhizosphere of buffelgrass. However, in the presence of buffelgrass and phenanthrene, the bacterial population preferentially responded to phenanthrene. The growth of buffelgrass was severely curtailed by phenanthrene in the absence of the bacterium. However, strain PM600 effectively protected buffelgrass against the phytotoxicity of phenanthrene.

Comparative study on the degradation of dibutyl phthalate by two newly isolated Pseudomonas sp. V21b and Comamonas sp. 51F

Directory of Open Access Journals (Sweden)

Vinay Kumar

2017-09-01

Full Text Available Dibutyl phthalate is (DBP the top priority toxicant responsible for carcinogenicity, teratogenicity and endocrine disruption. This study demonstrates the DBP degradation capability of the two newly isolated bacteria from municipal solid waste leachate samples. The isolated bacteria were designated as Pseudomonas sp. V21b and Comamonas sp. 51F after scanning electron microscopy, transmission electron microscopy, Gram-staining, antibiotic sensitivity tests, biochemical characterization, 16S-rRNA gene identification and phylogenetic studies. They were able to grow on DBP, benzyl butyl phthalate, monobutyl phthalate, diisodecyl phthalate, dioctyl phthalate, and protocatechuate. It was observed that Pseudomonas sp. V21b was more efficient in DBP degradation when compared with Comamonas sp. 51F. It degraded 57% and 76% of the initial DBP in minimal salt medium and in DBP contaminated samples respectively. Kinetics for the effects of DBP concentration on Pseudomonas sp. V21b and Comamonas sp. 51F growth was also evaluated. Stoichiometry for DBP degradation and biomass formation were compared for both the isolates. Two major metabolites diethyl phthalate and monobutyl phthalates were identified using GC–MS in the extracts. Key genes were amplified from the genomes of Pseudomonas sp. V21b and Comamonas sp. 51F. DBP degradation pathway was also proposed.

Quantitative proteomic analysis of ibuprofen-degrading Patulibacter sp. strain I11

DEFF Research Database (Denmark)

Almeida, Barbara; Kjeldal, Henrik; Lolas, Ihab Bishara Yousef

2013-01-01

was identified and quantified by gel based shotgun-proteomics. In total 251 unique proteins were quantitated using this approach. Biological process and pathway analysis indicated a number of proteins that were up-regulated in response to active degradation of ibuprofen, some of them are known to be involved...... in the degradation of aromatic compounds. Data analysis revealed that several of these proteins are likely involved in ibuprofen degradation by Patulibacter sp. strain I11.......Ibuprofen is the third most consumed pharmaceutical drug in the world. Several isolates have been shown to degrade ibuprofen, but very little is known about the biochemistry of this process. This study investigates the degradation of ibuprofen by Patulibacter sp. strain I11 by quantitative...

Proteogenomic Characterization of Monocyclic Aromatic Hydrocarbon Degradation Pathways in the Aniline-Degrading Bacterium Burkholderia sp. K24.

Directory of Open Access Journals (Sweden)

Sang-Yeop Lee

Full Text Available Burkholderia sp. K24, formerly known as Acinetobacter lwoffii K24, is a soil bacterium capable of utilizing aniline as its sole carbon and nitrogen source. Genomic sequence analysis revealed that this bacterium possesses putative gene clusters for biodegradation of various monocyclic aromatic hydrocarbons (MAHs, including benzene, toluene, and xylene (BTX, as well as aniline. We verified the proposed MAH biodegradation pathways by dioxygenase activity assays, RT-PCR, and LC/MS-based quantitative proteomic analyses. This proteogenomic approach revealed four independent degradation pathways, all converging into the citric acid cycle. Aniline and p-hydroxybenzoate degradation pathways converged into the β-ketoadipate pathway. Benzoate and toluene were degraded through the benzoyl-CoA degradation pathway. The xylene isomers, i.e., o-, m-, and p-xylene, were degraded via the extradiol cleavage pathways. Salicylate was degraded through the gentisate degradation pathway. Our results show that Burkholderia sp. K24 possesses versatile biodegradation pathways, which may be employed for efficient bioremediation of aniline and BTX.

Proteogenomic Characterization of Monocyclic Aromatic Hydrocarbon Degradation Pathways in the Aniline-Degrading Bacterium Burkholderia sp. K24

Science.gov (United States)

Yun, Sung Ho; Choi, Chi-Won; Yi, Yoon-Sun; Kim, Jonghyun; Chung, Young-Ho; Park, Edmond Changkyun; Kim, Seung Il

2016-01-01

Burkholderia sp. K24, formerly known as Acinetobacter lwoffii K24, is a soil bacterium capable of utilizing aniline as its sole carbon and nitrogen source. Genomic sequence analysis revealed that this bacterium possesses putative gene clusters for biodegradation of various monocyclic aromatic hydrocarbons (MAHs), including benzene, toluene, and xylene (BTX), as well as aniline. We verified the proposed MAH biodegradation pathways by dioxygenase activity assays, RT-PCR, and LC/MS-based quantitative proteomic analyses. This proteogenomic approach revealed four independent degradation pathways, all converging into the citric acid cycle. Aniline and p-hydroxybenzoate degradation pathways converged into the β-ketoadipate pathway. Benzoate and toluene were degraded through the benzoyl-CoA degradation pathway. The xylene isomers, i.e., o-, m-, and p-xylene, were degraded via the extradiol cleavage pathways. Salicylate was degraded through the gentisate degradation pathway. Our results show that Burkholderia sp. K24 possesses versatile biodegradation pathways, which may be employed for efficient bioremediation of aniline and BTX. PMID:27124467

Characterization of Sphingomonas isolates from Finnish and Swedish drinking water distribution systems.

Science.gov (United States)

Koskinen, R; Ali-Vehmas, T; Kämpfer, P; Laurikkala, M; Tsitko, I; Kostyal, E; Atroshi, F; Salkinoja-Salonen, M

2000-10-01

Sphingomonas species were commonly isolated from biofilms in drinking water distribution systems in Finland (three water meters) and Sweden (five water taps in different buildings). The Sphingomonas isolates (n = 38) were characterized by chemotaxonomic, physiological and phylogenetic methods. Fifteen isolates were designated to species Sphingomonas aromaticivorans, seven isolates to S. subterranea, two isolates to S. xenophaga and one isolate to S. stygia. Thirteen isolates represented one or more new species of Sphingomonas. Thirty-three isolates out of 38 grew at 5 degrees C on trypticase soy broth agar (TSBA) and may therefore proliferate in the Nordic drinking water pipeline where the temperature typically ranges from 2 to 12 degrees C. Thirty-three isolates out of 38 grew at 37 degrees C on TSBA and 15 isolates also grew on blood agar at 37 degrees C. Considering the potentially pathogenic features of sphingomonas, their presence in drinking water distribution systems may not be desirable.

The physiological effect of fluorene on Triticum aestivum, Medicago sativa, and Helianthus annus

Directory of Open Access Journals (Sweden)

Seyed Yahya Salehi-Lisar

2015-12-01

Full Text Available Polycyclic aromatic hydrocarbons (PAHs are widespread pollutants and can negatively affect plants. Fluorene is a prevalent PAH in the contaminated environment. In this study, the effects of higher concentrations of fluorene in soil on rate of seed germination, growth, and the physiological parameters of wheat, sunflower, and alfalfa were studied. The results showed that the higher concentration of fluorene decreased rate of seed germination and seedlings growth of plants. Wheat showed the highest resistance at seed germination and seedlings growth phases, and sunflower was the most sensitive species at both stages. Therefore, it was concluded that higher resistance at seed germination could be followed by the higher resistance of seedlings. Fluorene toxicity also induced oxidative stress in plants as shown by MDA accumulation in the plants. There was a significant correlation between the lower activity of CAT and MDA accumulation in the studied plants. Therefore, CAT could be an important enzyme involved in detoxification of ROS and plants resistance to fluorene toxicity. Depending on plant species and fluorene concentration, photosynthetic pigments content was differently affected.

Degradation of phytosterols in tobacco waste extract by a novel Paenibacillus sp.

Science.gov (United States)

Ye, Jianbin; Zhang, Zhan; Yan, Ji; Hao, Hui; Liu, Xiangzhen; Yang, Zongcan; Ma, Ke; Yang, Xuepeng; Mao, Duobin; Zhou, Hao

2017-11-01

Phytosterols have been demonstrated to be precursors of polycyclic aromatic hydrocarbons (PAHs) formed during biomass pyrolysis. Here, a novel Paenibacillus sp. was evaluated for its ability to degrade phytosterols in tobacco waste extract (TWE). The optimal conditions for cell growth and stigmasterol (a representative of phytosterols) degradation were 37 °C, pH 7.0, 1.0 g/L yeast extract, and 6.0 g/L glucose. Paenibacillus sp. could degrade stigmasterol under high concentrations of glucose (up to 130 g/L) and tolerate wide pH (5.0-9.0) and temperature (25-42 °C) ranges. The new strain could degrade stigmasterol completely into CO 2 and H 2 O, and no intermediate steroids were detected during the degradation process. Phytosterol degradation in TWE was demonstrated by high-performance liquid chromatography-tandem mass spectrometry. Under optimal conditions (37 °C, pH 7.0, with the exponential-phase cells), the total degradation ratio of phytosterols reached 38.5% in TWE, including 45.2% of stigmasterol, 37.4% of β-sitosterol, 27.3% of campesterol, and 28.7% of cholesterol. These results showed that Paenibacillus sp. is a candidate for phytosterol degradation in TWE and other biomass and is potentially useful in reducing the PAHs generated from biomass pyrolysis. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

Metalaxyl Degradation by Mucorales Strains Gongronella sp. and Rhizopus oryzae.

Science.gov (United States)

Martins, Maria Rosário; Santos, Cledir; Pereira, Pablo; Cruz-Morais, Júlio; Lima, Nelson

2017-12-14

In this study, the degradation of metalaxyl was investigated in the presence of two Mucorales strains, previously isolated from soil subjected to repeated treatments with this fungicide and selected after enrichment technique. Fungal strains were characterised by a polyphasic approach using phylogenetic analysis of the Internal Transcribed Spacer (ITS) gene region, phenotypic characterisation by Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) spectral analysis, and growth kinetics experiments. The strains were identified as Gongronella sp. and Rhizopus oryzae . The fungal growth kinetics in liquid cultures containing metalaxyl fits with Haldane model. Under laboratory conditions, the ability of Gongronella sp. and R. oryzae cultures to degrade metalaxyl was evaluated in liquid cultures and soil experiments. Both species were able to: (a) use metalaxyl as the main carbon and energy source; and (b) degrade metalaxyl in polluted soils, with rates around 1.0 mg kg - ¹ d - ¹. This suggests these strains could degrade metalaxyl in soils contaminated with this fungicide.

Metalaxyl Degradation by Mucorales Strains Gongronella sp. and Rhizopus oryzae

Directory of Open Access Journals (Sweden)

Maria Rosário Martins

2017-12-01

Full Text Available In this study, the degradation of metalaxyl was investigated in the presence of two Mucorales strains, previously isolated from soil subjected to repeated treatments with this fungicide and selected after enrichment technique. Fungal strains were characterised by a polyphasic approach using phylogenetic analysis of the Internal Transcribed Spacer (ITS gene region, phenotypic characterisation by Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS spectral analysis, and growth kinetics experiments. The strains were identified as Gongronella sp. and Rhizopus oryzae. The fungal growth kinetics in liquid cultures containing metalaxyl fits with Haldane model. Under laboratory conditions, the ability of Gongronella sp. and R. oryzae cultures to degrade metalaxyl was evaluated in liquid cultures and soil experiments. Both species were able to: (a use metalaxyl as the main carbon and energy source; and (b degrade metalaxyl in polluted soils, with rates around 1.0 mg kg−1 d−1. This suggests these strains could degrade metalaxyl in soils contaminated with this fungicide.

Optically enhanced nuclear cross polarization in acridine-doped fluorene

Energy Technology Data Exchange (ETDEWEB)

Oshiro, C.M.

1982-06-01

The objective of this work has been to create large polarizations of the dilute /sup 13/C nuclei in the solid state. The idea was to create /sup 1/H polarizations larger than Boltzmann and to use the proton enhanced nuclear induction spectroscopy cross polarization technique to then transfer this large polarization to the /sup 13/C spin system. Optical Nuclear Polarization (ONP) of acridine-doped fluorene single crystals was studied. In addition, ONP of powdered samples of the acridine-doped fluorene was studied. In general, many compounds do not crystallize easily or do not form large crystals suitable for NMR experiments. Powdered, amorphous and randomly dispersed samples are generally far more readily available than single crystals. One objective of this work has been to (first) create large /sup 1/H polarizations. Although large optical proton polarizations in single crystals have been reported previously, optically generated polarizations in powdered samples have not been reported. For these reasons, ONP studies of powdered samples of the acridine-doped fluorene were also undertaken. Using ONP in combination with the proton enhanced nuclear induction spectroscopy experiment, large /sup 13/C polarizations have been created in fluorene single crystals. These large /sup 13/C polarizations have permitted the determination of the seven incongruent chemical shielding tensors of the fluorene molecule. Part 2 of this thesis describes the proton enhanced nuclear induction spectroscopy experiment. Part 3 describes the ONP experiment. Part 4 is a description of the experimental set-up. Part 5 describes the data analysis for the determination of the chemical shielding tensors. Part 6 presents the results of the ONP experiments performed in this work and the chemical shielding tensors determined.

Optically enhanced nuclear cross polarization in acridine-doped fluorene

International Nuclear Information System (INIS)

Oshiro, C.M.

1982-06-01

The objective of this work has been to create large polarizations of the dilute 13 C nuclei in the solid state. The idea was to create 1 H polarizations larger than Boltzmann and to use the proton enhanced nuclear induction spectroscopy cross polarization technique to then transfer this large polarization to the 13 C spin system. Optical Nuclear Polarization (ONP) of acridine-doped fluorene single crystals was studied. In addition, ONP of powdered samples of the acridine-doped fluorene was studied. In general, many compounds do not crystallize easily or do not form large crystals suitable for NMR experiments. Powdered, amorphous and randomly dispersed samples are generally far more readily available than single crystals. One objective of this work has been to (first) create large 1 H polarizations. Although large optical proton polarizations in single crystals have been reported previously, optically generated polarizations in powdered samples have not been reported. For these reasons, ONP studies of powdered samples of the acridine-doped fluorene were also undertaken. Using ONP in combination with the proton enhanced nuclear induction spectroscopy experiment, large 13 C polarizations have been created in fluorene single crystals. These large 13 C polarizations have permitted the determination of the seven incongruent chemical shielding tensors of the fluorene molecule. Part 2 of this thesis describes the proton enhanced nuclear induction spectroscopy experiment. Part 3 describes the ONP experiment. Part 4 is a description of the experimental set-up. Part 5 describes the data analysis for the determination of the chemical shielding tensors. Part 6 presents the results of the ONP experiments performed in this work and the chemical shielding tensors determined

Isolation and characterization of mesotrione-degrading Bacillus sp. from soil

International Nuclear Information System (INIS)

Batisson, Isabelle; Crouzet, Olivier; Besse-Hoggan, Pascale; Sancelme, Martine; Mangot, Jean-Francois; Mallet, Clarisse; Bohatier, Jacques

2009-01-01

Dissipation kinetics of mesotrione, a new triketone herbicide, sprayed on soil from Limagne (Puy-de-Dome, France) showed that the soil microflora were able to biotransform it. Bacteria from this soil were cultured in mineral salt solution supplemented with mesotrione as sole source of carbon for the isolation of mesotrione-degrading bacteria. The bacterial community structure of the enrichment cultures was analyzed by temporal temperature gradient gel electrophoresis (TTGE). The TTGE fingerprints revealed that mesotrione had an impact on bacterial community structure only at its highest concentrations and showed mesotrione-sensitive and mesotrione-adapted strains. Two adapted strains, identified as Bacillus sp. and Arthrobacter sp., were isolated by colony hybridization methods. Biodegradation assays showed that only the Bacillus sp. strain was able to completely and rapidly biotransform mesotrione. Among several metabolites formed, 2-amino-4-methylsulfonylbenzoic acid (AMBA) accumulated in the medium. Although sulcotrione has a chemical structure closely resembling that of mesotrione, the isolates were unable to degrade it. - A Bacillus sp. strain isolated from soil was able to completely and rapidly biotransform the triketone herbicide mesotrione

First Report of Sphingomonas koreensis as a human pathogen in a patient with meningitis

DEFF Research Database (Denmark)

Marbjerg, Lis H; Gaini, Shahin; Justesen, Ulrik S

2015-01-01

Sphingomonas koreensis is an aerobic Gram-negative rod originally described in 2001 following isolation from natural mineral water in Korea. Here we report a case study with Sphingomonas koreensis as the causative agent of meningitis. To our knowledge, this is the first documented case of Sphingo......Sphingomonas koreensis is an aerobic Gram-negative rod originally described in 2001 following isolation from natural mineral water in Korea. Here we report a case study with Sphingomonas koreensis as the causative agent of meningitis. To our knowledge, this is the first documented case...

Enhancement of pyrene degradation efficacy of Synechocystis sp., by construction of an artificial microalgal-bacterial consortium

Directory of Open Access Journals (Sweden)

Jignasa G. Patel

2015-12-01

Full Text Available This study was carried out to investigate the ability of microalgae Synechocystis sp. to high molecular weight Polycyclic Aromatic Hydrocarbon pyrene (PYR and artificial microalgal–bacterial consortium at different concentrations. The consortium consisted of one axenic species Synechocystis sp. and two PYR-degrading bacteria with known complementary degradative capabilities viz. Pseudomonas sp. and Bacillus sp. The influence of PYR on growth in terms of chlorophyll-a were analysed, and it was found that in the presence of bacteria, Synechocystis sp. tremendously increased in growth as well as biodegradation capability, whereas Synechocystis sp. alone exhibited concentration-dependent decrease in growth and biodegradation ability. Degradation of PYR shows that the consortium could eliminate PYR by 94.1% at 50 mg/L; however, Synechocystis sp alone could degrade up to 36% at 1.5 mg/L after 16 days of incubation. The study revealed that microalgae grew better in the presence of the aerobic heterotrophic bacteria and provided them with necessary organics for efficient PYR degradation activities. Moreover, consortium JP-NKA7B2 grows efficiently on other xenobiotic compounds. The artificial consortia JP-NK is thus proven to be an effective and promising system for bioremediating PYR compound and could be suggested in degradation of PYR compound in hydrocarbon-polluted areas in situ and ex situ.

Degradation of morpholine by Mycobacterium sp. isolated from ...

African Journals Online (AJOL)

The biodegradation of morpholine has attracted much interest because morpholine causes environmental pollution. Ten species belonging to nine genera were tested for their abilities to degrade morpholine in mineral salts medium containing morpholine (1 g/l). Mycobacterium sp. isolated from polluted water sample ...

Biodegradation of Mixed PAHs by PAH-Degrading Endophytic Bacteria

Directory of Open Access Journals (Sweden)

Xuezhu Zhu

2016-08-01

Full Text Available Endophytic bacteria can promote plant growth, induce plant defence mechanisms, and increase plant resistance to organic contaminants. The aims of the present study were to isolate highly PAH-degrading endophytic bacteria from plants growing at PAH-contaminated sites and to evaluate the capabilities of these bacteria to degrade polycyclic aromatic hydrocarbons (PAHs in vitro, which will be beneficial for re-colonizing target plants and reducing plant PAH residues through the inoculation of plants with endophytic bacteria. Two endophytic bacterial strains P1 (Stenotrophomonas sp. and P3 (Pseudomonas sp., which degraded more than 90% of phenanthrene (PHE within 7 days, were isolated from Conyza canadensis and Trifolium pretense L., respectively. Both strains could use naphthalene (NAP, PHE, fluorene (FLR, pyrene (PYR, and benzo(apyrene (B(aP as the sole sources of carbon and energy. Moreover, these bacteria reduced the contamination of mixed PAHs at high levels after inoculation for 7 days; strain P1 degraded 98.0% NAP, 83.1% FLR, 87.8% PHE, 14.4% PYR, and 1.6% B(aP, and strain P3 degraded 95.3% NAP, 87.9% FLR, 90.4% PHE, 6.9% PYR, and negligible B(aP. Notably, the biodegradation of PAHs could be promoted through additional carbon and nitrogen nutrients; therein, beef extract was suggested as the optimal co-substrate for the degradation of PAHs by these two strains (99.1% PHE was degraded within 7 days. Compared with strain P1, strain P3 has more potential for the use in the removal of PAHs from plant tissues. These results provide a novel perspective in the reduction of plant PAH residues in PAH-contaminated sites through inoculating plants with highly PAH-degrading endophytic bacteria.

Proposal of the genus Sphingomonas sensu stricto and three new genera, Sphingobium, Novosphingobium and Sphingopyxis, on the basis of phylogenetic and chemotaxonomic analyses.

Science.gov (United States)

Takeuchi, M; Hamana, K; Hiraishi, A

2001-07-01

Phylogenetic analyses of 16S rRNA gene sequences by distance matrix and parsimony methods indicated that the currently known species of the genus Sphingomonas can be divided into four clusters. Some chemotaxonomic and phenotypic differences were noted among these clusters. Three new genera, Sphingobium, Novosphingobium and Sphingopyxis, are proposed in addition to the genus Sphingomonas sensu stricto. The genus Sphingobium is proposed to accommodate Sphingomonas chlorophenolica, Sphingomonas herbicidovorans and Sphingomonas yanoikuyae. The genus Novosphingobium is proposed for Sphingomonas aromaticivorans, Sphingomonas capsulata, Sphingomonas rosa, Sphingomonas stygia, Sphingomonas subarctica and Sphingomonas subterranea. Sphingomonas macrogoltabidus and Sphingomonas terrae are reclassified in the genus Sphingopyxis. The type species of Sphingobium, Novosphingobium and Sphingopyxis are Sphingobium yanoikuyae, Novosphingobium capsulatum and Sphingopyxis macrogoltabida, respectively.

Cometabolic Degradation of Dibenzofuran and Dibenzothiophene by a Naphthalene-Degrading Comamonas sp. JB.

Science.gov (United States)

Ji, Xiangyu; Xu, Jing; Ning, Shuxiang; Li, Nan; Tan, Liang; Shi, Shengnan

2017-12-01

Comamonas sp. JB was used to investigate the cometabolic degradation of dibenzofuran (DBF) and dibenzothiophene (DBT) with naphthalene as the primary substrate. Dehydrogenase and ATPase activity of the growing system with the presence of DBF and DBT were decreased when compared to only naphthalene in the growing system, indicating that the presence of DBF and DBT inhibited the metabolic activity of strain JB. The pathways and enzymes involved in the cometabolic degradation were tested. Examination of metabolites elucidated that strain JB cometabolically degraded DBF to 1,2-dihydroxydibenzofuran, subsequently to 2-hydroxy-4-(3'-oxo-3'H-benzofuran-2'-yliden)but-2-enoic acid, and finally to catechol. Meanwhile, strain JB cometabolically degraded DBT to 1,2-dihydroxydibenzothiophene and subsequently to the ring cleavage product. A series of naphthalene-degrading enzymes including naphthalene dioxygenase, 1,2-dihydroxynaphthalene dioxygenase, salicylaldehyde dehydrogenase, salicylate hydroxylase, and catechol 2,3-oxygenase have been detected, confirming that naphthalene was the real inducer of expression the degradation enzymes and metabolic pathways were controlled by naphthalene-degrading enzymes.

Supramolecular fluorene based materials

OpenAIRE

Abbel, R.J.

2008-01-01

This thesis describes the use of noncovalent interactions in order to manipulate and control the self-assembly and morphology of electroactive fluorene-based materials. The supramolecular arrangement of p-conjugated polymers and oligomers can strongly influence their electronic and photophysical properties. Therefore, a detailed understanding of such organisation processes is essential for the optimisation of the performance of these materials as applied in optoelectronic devices. In order to...

Thermal high pressure hydrogenolysis II. The thermal high pressure hydrocracking of fluorene

NARCIS (Netherlands)

Oltay, Ernst; Penninger, Johannes M.L.; Konter, Willem A.N.

1973-01-01

The thermal hydrocracking of fluorene was investigated in the temperature range of 400 to 480 °C and hydrogen pressures of up to 375 atm. As main reaction products were found 2-methylbiphenyl, biphenyl, toluene and benzene. They account for about 90% of the converted fluorene. Only very low

Efecto de la inoculación de la cepa Sphingomonas paucimobilis 20006FA sobre la composición de un consorcio bacteriano degradador de fenantreno Effect of the inoculant strain Sphingomonas paucimobilis 20006FA on the bacterial composition of a phenanthrene-degrading consortium

Directory of Open Access Journals (Sweden)

L. Madueño

2009-06-01

Full Text Available Se estudió el efecto de la inoculación con la cepa Sphingomonas paucimobilis 20006FA sobre la composición bacteriana de un consorcio degradador de fenantreno en cultivos discontinuos (batch con 8 repiques sucesivos. El consorcio original se obtuvo a partir de un suelo prístino. A los fines del estudio, se obtuvieron y mantuvieron dos consorcios: uno inoculado (F200+I y otro sin inocular (F200. Se estudió la diversidad bacteriana de los consorcios mediante el análisis de microorganismos cultivables (por caracterización fenotípica y genotípica y totales (por PCR-DGGE. A lo largo de los repiques sucesivos pudo observarse en ambos consorcios una tendencia a la pérdida de la capacidad degradadora de fenantreno, acompañada por una disminución de la diversidad bacteriana. Si bien la inoculación no produjo cambios significativos en la capacidad degradadora de fenantreno de los consorcios (29,9% para F200 y 27,6% para F200+I hacia el tercer repique, sí produjo cambios en la composición bacteriana, ya que los perfiles de DGGE revelaron una dinámica estructural diferente en el consorcio inoculado. En ambos consorcios se pudo observar la presencia de una banda intensa posicionada a la misma altura que el ADN del inóculo en el gel de DGGE; sin embargo, los cultivos aislados de los consorcios que presentaban idéntica posición de banda en el perfil PCR-DGGE que la cepa S. paucimobilis 20006FA mostraron baja similitud con la cepa inoculada mediante la técnica de RAPD.The effect of the inoculant strain Sphingomonas paucimobilis 20006FA on the bacterial composition of a phenanthrene-degrading consortium obtained from a pristine soil in sequencing batch cultures was studied. Inoculated (F200+I and non-inoculated (F200 phenanthrene-degrading consortia, were obtained. Bacterial diversity of consortia was studied at cultivable (phenotype and genotype characterization and non-cultivable (PCR-DGGE levels. During the successive cultures, a loss in

Endoftalmitis poscirugía de catarata por Sphingomonas paucimobilis

Directory of Open Access Journals (Sweden)

Omar Mauri Garrido

Full Text Available Se presenta la caracterización y manejo terapéutico de un caso de endoftalmitis bacteriana posoperatoria causada por el germen Sphingomonas paucimobilis. La endoftalmitis es la inflamación de los tejidos intraoculares, considerada como la más devastadora de las complicaciones posoperatorias; posee pronóstico visual muy reservado y un elevado riesgo de secuela. Las Sphingomonas paucimobilis son bacterias gramnegativas con forma de bacilo, quimioheterótrofa y estrictamente aerobias que causan enfermedades en los seres humanos, principalmente infecciones hospitalarias que típicamente son tratadas fácilmente con antibióticos. Por sus capacidades biodegradantes y biosintéticas, son pocos los reportes hallados de infección intraocular por este germen. El pronóstico visual es favorable con un diagnóstico precoz y la aplicación del tratamiento adecuado. En este artículo se presentan un caso de endoftalmitis poscirugía de catarata por Sphingomonas paucimobilis reportado en Cuba en el mes de septiembre de 2009.

Sphingomonas paucimobilis presenting as acute phlebitis: A case report

Directory of Open Access Journals (Sweden)

Saqib Walayat

2018-01-01

Full Text Available Sphingomonas paucimobilis is a strictly aerobic, non-spore-forming Gram-negative bacillus, ubiquitous bacterium, thought to be an opportunistic pathogen and is rarely reported in clinical settings. Here in, is the first case report of Acute Sphingomonas phlebitis secondary to intravenous (IV drug use. We present the case of a 39-year-old male who initially presented with pain in his right upper extremity, fevers and chills of three week duration. He admitted to regularly injecting heroin in his distal right upper extremity with visible erythema, tenderness and streaking along the path of vein along the injection site. Radiographic studies including X-ray of the right arm, ultrasound and a subsequent MRI of the right arm were not significant for any osteomyelitis, deep venous thrombus, abscess, cellulitis, osteomyelitis, or pyomyositis. Blood culture grew Sphingomonas paucimobilis. Patient was initially started on vancomycin and piperacillin/tazobactam and subsequently switched to levofloxacin to complete a 14 day course. Patient admitted to using toilet water to mix his heroin which we suspect may have been the source of his bacteremia. Since it was first reported in 1979, a wide variety of community-acquired and hospital-acquired infections have been attributed to this Sphingomonas. It is ubiquitous to natural environment. We believe that due to its widespread habitat and ability to survive in stress conditions it could be a potential future threat in the era of increasing antimicrobial resistance globally. More research needs to be done on early identification, pathogenesis, treatment and eradication of the organism.

Degradation of dibenzofuran via multiple dioxygenation by a newly isolated Agrobacterium sp. PH-08.

Science.gov (United States)

Le, T T; Murugesan, K; Nam, I-H; Jeon, J-R; Chang, Y-S

2014-03-01

To demonstrate the biodegradation of dibenzofuran (DF) and its structural analogs by a newly isolated Agrobacterium sp. PH-08. To assess the biodegradation potential of newly isolated Agrobacterium sp. PH-08, various substrates were evaluated as sole carbon sources in growth and biotransformation experiments. ESI LC-MS/MS analysis revealed the presence of angular degrading by-products as well as lateral dioxygenation metabolites in the upper pathway. The metabolites in the lower pathway also were detected. In addition, the cometabolically degraded daughter compounds of DF-related compounds such as BP and dibenzothiophene (DBT) in dual substrate degradation were observed. Strain PH-08 exhibited the evidence of meta-cleavage pathway as confirmed by the activity and gene expression of catechol-2,3-dioxygenase. Newly isolated bacterial strain, Agrobacterium sp. PH-08, grew well with and degraded DF via both angular and lateral dioxygenation as demonstrated by metabolites identified through ESI LC-MS/MS and GC-MS analyses. The other heterocyclic pollutants were also cometabolically degraded. Few reports have described the complete degradation of DF by a cometabolic lateral pathway. Our study demonstrates the novel results that the newly isolated strain utilized the DF as a sole carbon source and mineralized it via multiple dioxygenation. © 2013 The Society for Applied Microbiology.

Potential Degradation of Swainsonine by Intracellular Enzymes of Arthrobacter sp. HW08

Directory of Open Access Journals (Sweden)

Haili Li

2013-11-01

Full Text Available Swainsonine (SW is a toxin produced by locoweeds and harmful to the livestock industry. Degrading SW by Arthrobacter sp. HW08 was demonstrated as a promising way to deal with SW poisoning. However, it is unknown which part of the subcellular enzymes in Arthrobacter sp. HW08 is responsible for biodegrading SW and whether the metabolites are atoxic. In this study, intracellular and extracellular enzymes of Arthrobacter sp. HW08 were isolated and their enzyme activity was evaluated. The metabolites were fed to mice, and physiological and histological properties of the treated mice were investigated. The results showed that only intracellular enzyme of Arthrobacter sp. HW08 (IEHW08 could degrade SW efficiently. Compared with mice in SW treatment group, mice in SW + IEHW08 treatment group (1 increased their body weights; (2 showed higher number of platelets and lower number of white blood cells; (3 decreased the levels of creatinine, urea nitrogen, alanine transaminase and aspartate aminotransferase in serum; (4 reduced the number of vacuolated cells in cerebellum, liver and kidney. All these data demonstrate that IEHW08 was potentially safe for mice, while keeping the capacity of degrading SW. This study indicates a possible application of IEHW08 as an additive in the livestock industry to protect animals from SW poisoning.

Rizoremediação de pentaclorofenol em um solo argiloso por sphingomonas chlorophenolica ATCC 39723 Pentachlorophenol rhizoremediation in a loamy soil by sphingomonas chlorophenolica ATCC 39723

Directory of Open Access Journals (Sweden)

Rosemeri I. Dams

2007-12-01

Full Text Available O principal objetivo deste trabalho foi estudar a degradação de PCP por Sphingomonas chlorophenolicaem solo argiloso na presença e ausência de trigo. As concentrações de PCP foram determinadas através de Análises de Alta Performance de Cromatografia Líquida. Os efeitos tóxicos de PCP foram estudados através do monitoramento do crescimento das plantas. A biodegradação de PCP por S. chlorophenolica foi acompanhada por testes de bioluminescência de Escherichia coli HB101 pUCD607 e contagens bacterianas no solo e nas raízes. A degradação de PCP ocorreu de forma mais rápida no solo plantado e inoculado quando comparada ao solo sem plantas. Houve um aumento significativo nas populações dos organismos testados nas raízes quando comparadas com as populações presentes no solo. O monitoramento do crescimento da planta mostrou o papel protetor exercido pela S.chlorophenolica contra a toxicidade do PCP.The main objective of this study was study the PCP degradation by Sphingomonas chlorophenolica in a loamy soil in the presence and absence of plants (Winter wheat. Measurements of PCP concentrations were carried out in a laboratory basis using High performance liquid chromatography analysis (HPLC. The toxic effect of PCP on plants was studied through the monitoring of the plant growth. The biodegradation of PCP by S. chlorophenolica in soil was assessed with a bioluminescence assay of Escherichia coli HB101 pUCD607 and bacterial analyses in roots and soil. The planted and inoculated soil showed a faster degradation when compared to the inoculated soil without plants. There was a significative increase in the populations of the organisms tested in the roots when compared to the soil. The monitoring of the plant growth showed a protective role of S. chlorophenolica against the toxicity of PCP in the loamy soil.

White organic light emitting diodes based on fluorene-carbazole dendrimers

International Nuclear Information System (INIS)

Usluer, Özlem; Demic, Serafettin; Kus, Mahmut; Özel, Faruk; Serdar Sariciftci, Niyazi

2014-01-01

In this paper, we report on theProd. Type: FTP fabrication and characterization of blue and white light emitting devices based on two fluorene-carbazole containing dendrimers and para-sexiphenyl (6P) oligomers. Blue light emitting diodes were fabricated using 9′,9″-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis-9′H-9,3′:6′,9″-tercarbazole (OFC-G2) and 9′,9″-(9,9′-spirobi[fluorene]-2,7-diyl)bis-9′H-9,3′:6′,9″-tercarbazole (SBFC-G2) dendrimers as a hole transport and emissive layer (EML) and 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) as an electron transport layer. White light emitting diodes were fabricated using 6P and these two dendrimers as an EML. OLED device with the structure of ITO/PEDOT:PSS (50 nm)/OFC-G2 (40 nm)/6P (20 nm)/LiF:Al (0.5:100 nm) shows maximum luminance of nearly 1400 cd/m 2 and a Commission Internationale de l'Eclairage chromaticity coordinates of (0.27, 0.30) at 12 V. -- Highlights: • White organic light emitting diodes have been fabricated using two fluorene-carbazole dendrimers and para-sexiphenyl (6P) oligomers. • When only these two dendrimers are used as EML, OLED devices are emitted blue light. • The emission colors of OLED devices change from blue to white when 6P is coated on dendrimer films

Fluorene biodegradation potentials of Bacillus strains isolated from ...

African Journals Online (AJOL)

Fluorene biodegradation potentials of Bacillus strains isolated from tropical ... Bacillus strains, putatively identified as Bacillus subtilis BM1 and Bacillus amyloliquefaciens BR1 were ... African Journal of Biotechnology, Vol 13(14), 1554-1559 ...

Degradation of phytosteril into androstenedione by mycobacterium SP-UV-8

International Nuclear Information System (INIS)

Yang Ying; Jiang Shaotong; Wei Zhaojun; Zhao Yanyan; Sunxiaoming

2009-01-01

The fermentation process of Mycobacterium sp-UV-8 was studied in batch system, and a kinetic model was proposed based on the Logistic and Leudeking-piret equations for microorganism growth, product formation and substrate consumption. Depending on the evaluated model parameters, the model appears to provide a reasonable description for the fermentation process,and the average relative error was no more than 7%. The calculated results of models were compared satisfactorily with experimental data, which offers assurance for the industrial design and production throught degradation of phytosterol by Mycobacterium sp-UV-8. (authors)

White organic light emitting diodes based on fluorene-carbazole dendrimers

Energy Technology Data Exchange (ETDEWEB)

Usluer, Özlem, E-mail: usluerozlem@yahoo.com.tr [Department of Chemistry, Muğla Sıtkı Koçman University, 48000 Muğla (Turkey); Demic, Serafettin [Department of Materials Science and Engineering, Izmir Katip Çelebi University, 35620 Çiğli, Izmir (Turkey); Kus, Mahmut, E-mail: mahmutkus1@gmail.com [Chemical Engineering Department and Advanced Technology R and D Center, Selçuk University, Konya (Turkey); Özel, Faruk [Chemical Engineering Department and Advanced Technology R and D Center, Selçuk University, Konya (Turkey); Serdar Sariciftci, Niyazi [Linz Institute for Organic Solar Cells (LIOS), Physical Chemistry, Johannes Kepler University, Altenbergerstr. 69, A-4040 Linz (Austria)

2014-02-15

In this paper, we report on theProd. Type: FTP fabrication and characterization of blue and white light emitting devices based on two fluorene-carbazole containing dendrimers and para-sexiphenyl (6P) oligomers. Blue light emitting diodes were fabricated using 9′,9″-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis-9′H-9,3′:6′,9″-tercarbazole (OFC-G2) and 9′,9″-(9,9′-spirobi[fluorene]-2,7-diyl)bis-9′H-9,3′:6′,9″-tercarbazole (SBFC-G2) dendrimers as a hole transport and emissive layer (EML) and 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) as an electron transport layer. White light emitting diodes were fabricated using 6P and these two dendrimers as an EML. OLED device with the structure of ITO/PEDOT:PSS (50 nm)/OFC-G2 (40 nm)/6P (20 nm)/LiF:Al (0.5:100 nm) shows maximum luminance of nearly 1400 cd/m{sup 2} and a Commission Internationale de l'Eclairage chromaticity coordinates of (0.27, 0.30) at 12 V. -- Highlights: • White organic light emitting diodes have been fabricated using two fluorene-carbazole dendrimers and para-sexiphenyl (6P) oligomers. • When only these two dendrimers are used as EML, OLED devices are emitted blue light. • The emission colors of OLED devices change from blue to white when 6P is coated on dendrimer films.

Characterization of naphthalene degradation by Streptomyces sp. QWE-5 isolated from active sludge.

Science.gov (United States)

Xu, Peng; Ma, Wencheng; Han, Hongjun; Hou, Baolin; Jia, Shengyong

2014-01-01

A bacterial strain, QWE-5, which utilized naphthalene as its sole carbon and energy source, was isolated and identified as Streptomyces sp. It was a Gram-positive, spore-forming bacterium with a flagellum, with whole, smooth, convex and wet colonies. The optimal temperature and pH for QWE-5 were 35 °C and 7.0, respectively. The QWE-5 strain was capable of completely degrading naphthalene at a concentration as high as 100 mg/L. At initial naphthalene concentrations of 10, 20, 50, 80 and 100 mg/L, complete degradation was achieved within 32, 56, 96, 120 and 144 h, respectively. Kinetics of naphthalene degradation was described using the Andrews equation. The kinetic parameters were as follows: qmax (maximum specific degradation rate) = 1.56 h⁻¹, Ks (half-rate constant) = 60.34 mg/L, and KI (substrate-inhibition constant) = 81.76 mg/L. Metabolic intermediates were identified by gas chromatography and mass spectrometry, allowing a new degradation pathway for naphthalene to be proposed. In this pathway, monooxygenation of naphthalene yielded naphthalen-1-ol. Further degradation by Streptomyces sp. QWE-5 produced acetophenone, followed by adipic acid, which was produced as a combination of decarboxylation and hydroxylation processes.

Aerobic degradation of 4-nitroaniline (4-NA) via novel degradation intermediates by Rhodococcus sp. strain FK48

Energy Technology Data Exchange (ETDEWEB)

Khan, Fazlurrahman; Pandey, Janmejay; Vikram, Surendra; Pal, Deepika; Cameotra, Swaranjit Singh, E-mail: ssc@imtech.res.in

2013-06-15

Highlights: • This study reports isolation of a novel bacterium capable of mineralizing 4-nitroaniline (4-NA). • This bacterium has been identified as Rhodococcus sp. strain FK48. • Strain FK48 degrades 4-NA via a novel aerobic degradation pathway that involves 4-AP and 1,2,4-BT. • Subsequent degradation proceeds via ring fission and formation of maleylacetate. • This is the first report showing elucidation of catabolic pathway for microbial degradation 4-NA. -- Abstract: An aerobic strain, Rhodococcus sp. strain FK48, capable of growing on 4-nitroaniline (4-NA) as the sole source of carbon, nitrogen, and energy has been isolated from enrichment cultures originating from contaminated soil samples. During growth studies with non- induced cells of FK48 catalyzed sequential denitrification (release of NO{sub 2} substituent) and deamination (release of NH{sub 2} substituent) of 4-NA. However, none of the degradation intermediates could be identified with growth studies. During resting cell studies, 4-NA-induced cells of strain FK48 transformed 4-NA via a previously unknown pathway which involved oxidative hydroxylation leading to formation of 4-aminophenol (4-AP). Subsequent degradation involved oxidated deamination of 4-AP and formation of 1,2,4-benzenetriol (BT) as the major identified terminal aromatic intermediate. Identification of these intermediates was ascertained by HPLC, and GC–MS analyses of the culture supernatants. 4-NA-induced cells of strain FK48 showed positive activity for 1,2,4-benzenetriol dioxygenase in spectrophotometric assay. This is the first conclusive study on aerobic microbial degradation of 4-NA and elucidation of corresponding metabolic pathway.

Aerobic degradation of 4-nitroaniline (4-NA) via novel degradation intermediates by Rhodococcus sp. strain FK48

International Nuclear Information System (INIS)

Khan, Fazlurrahman; Pandey, Janmejay; Vikram, Surendra; Pal, Deepika; Cameotra, Swaranjit Singh

2013-01-01

Highlights: • This study reports isolation of a novel bacterium capable of mineralizing 4-nitroaniline (4-NA). • This bacterium has been identified as Rhodococcus sp. strain FK48. • Strain FK48 degrades 4-NA via a novel aerobic degradation pathway that involves 4-AP and 1,2,4-BT. • Subsequent degradation proceeds via ring fission and formation of maleylacetate. • This is the first report showing elucidation of catabolic pathway for microbial degradation 4-NA. -- Abstract: An aerobic strain, Rhodococcus sp. strain FK48, capable of growing on 4-nitroaniline (4-NA) as the sole source of carbon, nitrogen, and energy has been isolated from enrichment cultures originating from contaminated soil samples. During growth studies with non- induced cells of FK48 catalyzed sequential denitrification (release of NO 2 substituent) and deamination (release of NH 2 substituent) of 4-NA. However, none of the degradation intermediates could be identified with growth studies. During resting cell studies, 4-NA-induced cells of strain FK48 transformed 4-NA via a previously unknown pathway which involved oxidative hydroxylation leading to formation of 4-aminophenol (4-AP). Subsequent degradation involved oxidated deamination of 4-AP and formation of 1,2,4-benzenetriol (BT) as the major identified terminal aromatic intermediate. Identification of these intermediates was ascertained by HPLC, and GC–MS analyses of the culture supernatants. 4-NA-induced cells of strain FK48 showed positive activity for 1,2,4-benzenetriol dioxygenase in spectrophotometric assay. This is the first conclusive study on aerobic microbial degradation of 4-NA and elucidation of corresponding metabolic pathway

Electronic transitions of fluorene, dibenzofuran, carbazole, and dibenzothiophene

DEFF Research Database (Denmark)

Nguyen, Duy Duc; Trunk, John; Nakhimovsky, Lina

2010-01-01

A comparative study of the electronic transitions of fluorene and its hetero-analogues dibenzofuran, carbazole, and dibenzothiophene was performed in a wide energy range. Gas phase, crystal phase, and linear dichroism electronic transmittance spectra were measured with synchrotron radiation...

The effect of media composition on EDTA degradation by Agrobacterium sp

International Nuclear Information System (INIS)

Palumbo, A.V.; Lee, S.Y.; Boerman, P.

1994-01-01

EDTA degradation by an Agrobacterium sp. has been examined by quantifying 14 C-labeled CO 2 produced from iron-[2- 14 C] EDTA and by measured loss of nonlabeled EDTA by HPLC. Fe-EDTA degradation resulted in a rise in pH, nitrate concentration, and ammonia concentration. Addition of glycerol resulted in suppression of Fe-EDTA degradation and in a decrease in pH and NH 4 + concentration in the media. Addition of peptone or yeast extract did not affect degradation. Some of the components (e.g., biotin) of the media are not necessary for growth and biodegradation. Although cobalt-EDTA cannot be degraded, ferrous iron can be added to displace the cobalt. The purpose was to relate the results to remediation of radionuclide-contaminated soils. 12 refs., 4 figs., 2 tabs

Fluorene and Phenanthrene Uptake and Accumulation by Wheat, Alfalfa and Sunflower from the Contaminated Soil.

Science.gov (United States)

Salehi-Lisar, Seyed Yahya; Deljoo, Somaye; Harzandi, Ahmad Mosen

2015-01-01

Polycyclic Aromatic Hydrocarbons (PAHs) are diverse organic contaminants released into the environment by both natural and anthropogenic activities. These compounds have negative impacts on plants growth and development. Although there are many reports on their existence in different parts of plant, their uptake and translocation pathways and mechanisms are not well understood yet. This paper highlights the uptake, translocation and accumulation of PAHs by wheat, sunflower and alfalfa through an experimental study under controlled conditions. Seeds were cultivated in a soil containing 50 mg/kg of phenanthrene and fluorene and their concentrations in plants roots and shoots were determined using a gas chromatograph after 7 and 14 days. The results showed that phenanthrene and fluorene concentrations in the treated plants were increased over the time. PAHs bioavailability was time and species dependent and generally, phenanthrene uptake and translocation was faster than that of fluorene, probably due to their higher Kow. Fluorene tended to accumulate in roots, but phenanthrene was transported to aerial parts of plants.

Novel Pathway of Salicylate Degradation by Streptomyces sp. Strain WA46

OpenAIRE

Ishiyama, Daisuke; Vujaklija, Dusica; Davies, Julian

2004-01-01

A novel salicylate-degrading Streptomyces sp., strain WA46, was identified by UV fluorescence on solid minimal medium containing salicylate; trace amounts of gentisate were detected by high-pressure liquid chromatography when strain WA46 was grown with salicylate. PCR amplification of WA46 DNA with degenerate primers for gentisate 1,2-dioxygenase (GDO) genes produced an amplicon of the expected size. Sequential PCR with nested GDO primers was then used to identify a salicylate degradation gen...

Genome sequence of the agar-degrading marine bacterium Alteromonadaceae sp. strain G7.

Science.gov (United States)

Kwak, Min-Jung; Song, Ju Yeon; Kim, Byung Kwon; Chi, Won-Jae; Kwon, Soon-Kyeong; Choi, Soobeom; Chang, Yong-Keun; Hong, Soon-Kwang; Kim, Jihyun F

2012-12-01

Here, we present the high-quality draft genome sequence of the agar-degrading marine gammaproteobacterium Alteromonadaceae sp. strain G7, which was isolated from coastal seawater to be utilized as a bioresource for production of agar-derived biofuels. The 3.91-Mb genome contains a number of genes encoding algal polysaccharide-degrading enzymes such as agarases and sulfatases.

Genome Sequence of the Agar-Degrading Marine Bacterium Alteromonadaceae sp. Strain G7

OpenAIRE

Kwak, Min-Jung; Song, Ju Yeon; Kim, Byung Kwon; Chi, Won-Jae; Kwon, Soon-Kyeong; Choi, Soobeom; Chang, Yong-Keun; Hong, Soon-Kwang; Kim, Jihyun F.

2012-01-01

Here, we present the high-quality draft genome sequence of the agar-degrading marine gammaproteobacterium Alteromonadaceae sp. strain G7, which was isolated from coastal seawater to be utilized as a bioresource for production of agar-derived biofuels. The 3.91-Mb genome contains a number of genes encoding algal polysaccharide-degrading enzymes such as agarases and sulfatases.

Enhanced degradation of 2-nitrotoluene by immobilized cells of Micrococcus sp. strain SMN-1.

Science.gov (United States)

Mulla, Sikandar I; Talwar, Manjunatha P; Bagewadi, Zabin K; Hoskeri, Robertcyril S; Ninnekar, Harichandra Z

2013-02-01

Nitrotoluenes are the toxic pollutants of the environment because of their large scale use in the production of explosives. Biodegradation of such chemicals by microorganisms may provide an effective method for their detoxification. We have studied the degradation of 2-nitrotoluene by cells of Micrococcus sp. strain SMN-1 immobilized in various matrices such as polyurethane foam (PUF), sodium alginate (SA), sodium alginate-polyvinyl alcohol (SA-PVA), agar and polyacrylamide. The rate of degradation of 15 and 30 mM 2-nitrotoluene by freely suspended cells and immobilized cells in batches and fed-batch with shaken cultures were compared. The PUF-immobilized cells achieved higher degradation of 15 and 30 mM 2-nitrotoluene than freely suspended cells and the cells immobilized in SA-PVA, polyacrylamide, SA and agar. The PUF-immobilized cells could be reused more than 24 cycles without loosing their degradation capacity and showed more tolerance to pH and temperature changes than freely suspended cells. These results revealed the enhanced rate of degradation of 2-nitrotoluene by PUF-immobilized cells of Micrococcus sp. strain SMN-1. Copyright © 2012 Elsevier Ltd. All rights reserved.

Adhesion to sand and ability to mineralise low pesticide concentrations are required for efficient bioaugmentation of flow-through sand filters

DEFF Research Database (Denmark)

Samuelsen, Elin Djurhuus; Badawi, Nora; Nybroe, Ole

2017-01-01

(Sphingomonas sp. PM2, Sphingomonas sp. ERG5, Burkholderia sp. TFD34, Cupriavidus sp. TFD38) were characterised with regard to their motility, cell surface hydrophobicity, biofilm formation, adhesion behaviour and ability to mineralise MCPA. Strains PM2 and ERG5 were non-motile and hydrophobic, whilst strains...... TFD34 and TFD38 were motile and less hydrophobic. All the strains except ERG5 showed low biofilm formation on polystyrene, although it was significantly higher on glass. PM2 was the most efficient MCPA degrader as it displayed no lag phase and reached >50 % mineralisation at all concentrations (0.......0016-25 mg L(-1)). PM2 adhered significantly better to sand than the other strains. No link was found between motility, biofilm formation and the ability to adhere to sand. PM2 completely removed MCPA for 14 days when inoculated in sand columns with a constant inlet of 1 mg L(-1) MCPA. These results...

Immobilization of Bacillus sp. in mesoporous activated carbon for degradation of sulphonated phenolic compound in wastewater

Energy Technology Data Exchange (ETDEWEB)

Sekaran, G., E-mail: ganesansekaran@gmail.com [Environmental Technology Division, Council of Scientific and Industrial Research (CSIR), Central Leather Research Institute (CLRI), Adyar, Chennai-600 020 (India); Karthikeyan, S. [Environmental Technology Division, Council of Scientific and Industrial Research (CSIR), Central Leather Research Institute (CLRI), Adyar, Chennai-600 020 (India); Gupta, V.K. [Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee-247 667 (India); Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia); Boopathy, R.; Maharaja, P. [Environmental Technology Division, Council of Scientific and Industrial Research (CSIR), Central Leather Research Institute (CLRI), Adyar, Chennai-600 020 (India)

2013-03-01

Xenobiotic compounds are used in considerable quantities in leather industries besides natural organic and inorganic compounds. These compounds resist biological degradation and thus they remain in the treated wastewater in the unaltered molecular configurations. Immobilization of organisms in carrier matrices protects them from shock load application and from the toxicity of chemicals in bulk liquid phase. Mesoporous activated carbon (MAC) has been considered in the present study as the carrier matrix for the immobilization of Bacillus sp. isolated from Effluent Treatment Plant (ETP) employed for the treatment of wastewater containing sulphonated phenolic (SP) compounds. Temperature, pH, concentration, particle size and mass of MAC were observed to influence the immobilization behavior of Bacillus sp. The percentage immobilization of Bacillus sp. was the maximum at pH 7.0, temperature 20 Degree-Sign C and at particle size 300 {mu}m. Enthalpy, free energy and entropy of immobilization were - 46.9 kJ mol{sup -1}, - 1.19 kJ mol{sup -1} and - 161.36 J K{sup -1} mol{sup -1} respectively at pH 7.0, temperature 20 Degree-Sign C and particle size 300 {mu}m. Higher values of {Delta}H{sup 0} indicate the firm bonding of the Bacillus sp. in MAC. Degradation of aqueous sulphonated phenolic compound by Bacillus sp. immobilized in MAC followed pseudo first order rate kinetics with rate constant 1.12 Multiplication-Sign 10{sup -2} min{sup -1}. Highlights: Black-Right-Pointing-Pointer Degradation on phenolic syntan using immobilized activated carbon as catalyst. Black-Right-Pointing-Pointer Bacillus sp. immobilized cell reactor removed all refractory organic loads. Black-Right-Pointing-Pointer The removal mechanism is due to co-metabolism between carbon and organisms. Black-Right-Pointing-Pointer The organics are completely metabolized rather than adsorption.

An integrated (nano-bio) technique for degradation of γ-HCH contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Singh, Ritu [Ecotoxicology Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001, UP (India); Analytical Chemistry Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001, UP (India); Manickam, Natesan [Environmental Biotechnology Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001, UP (India); Mudiam, Mohana Krishna Reddy [Analytical Chemistry Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001, UP (India); Murthy, Ramesh Chandra, E-mail: murthyrc729@gmail.com [Analytical Chemistry Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001, UP (India); Misra, Virendra, E-mail: virendra_misra2001@yahoo.co.in [Ecotoxicology Division, CSIR-Indian Institute of Toxicology Research, Post Box 80, Mahatma Gandhi Marg, Lucknow 226 001, UP (India)

2013-08-15

Highlights: • An integrated (nano-bio) technique is employed to degrade γ-HCH in soil. • Degradation efficiency of γ-HCH in integrated and individual systems is compared. • Synergistic effect was noticed on γ-HCH degradation in integrated system. • Integrated system was found 1.7–2.1 times more efficient than individual methods. • This technique could be exploited for other chlorinated pesticides as well. -- Abstract: We have evaluated the effect of an integrated (nano-bio) technique involving the use of stabilized Pd/Fe{sup 0} bimetallic nanoparticles (CMC-Pd/nFe{sup 0}) and a Sphingomonas sp. strain NM05, on the degradation of γ-HCH in soil. Factors affecting degradation such as pH, incubation temperature and γ-HCH initial concentration were also studied. The results revealed that γ-HCH degradation efficiency is ∼ 1.7–2.1 times greater in integrated system as compared to system containing either NM05 or CMC-Pd/nFe{sup 0} alone. The integration showed synergistic effect on γ-HCH degradation. Further, cell growth studies indicated that NM05 gets well acclimatized to nanoparticles, showing potential growth in the presence of CMC-Pd/nFe{sup 0} with respect to control system. This study signifies the potential efficacy of integrated technique to become an effective alternative remedial tool for γ-HCH contaminated soil. Further research in this direction could lead to the development of effective remediation strategies for other isomers of HCH and other chlorinated pesticides as well.

Large-scale bioreactor production of the herbicide-degrading Aminobacter sp. strain MSH1

DEFF Research Database (Denmark)

Schultz-Jensen, Nadja; Knudsen, Berith Elkær; Frkova, Zuzana

2014-01-01

The Aminobacter sp. strain MSH1 has potential for pesticide bioremediation because it degrades the herbicide metabolite 2,6-dichlorobenzamide (BAM). Production of the BAM-degrading bacterium using aerobic bioreactor fermentation was investigated. A mineral salt medium limited for carbon and with ......The Aminobacter sp. strain MSH1 has potential for pesticide bioremediation because it degrades the herbicide metabolite 2,6-dichlorobenzamide (BAM). Production of the BAM-degrading bacterium using aerobic bioreactor fermentation was investigated. A mineral salt medium limited for carbon...... and with an element composition similar to the strain was generated. The optimal pH and temperature for strain growth were determined using shaker flasks and verified in bioreactors. Glucose, fructose, and glycerol were suitable carbon sources for MSH1 (μ =0.1 h−1); slower growth was observed on succinate and acetic...... acid (μ =0.01 h−1). Standard conditions for growth of theMSH1 strain were defined at pH 7 and 25 °C, with glucose as the carbon source. In bioreactors (1 and 5 L), the specific growth rate of MSH1 increased from μ =0.1 h−1 on traditional mineral salt medium to μ =0.18 h−1 on the optimized mineral salt...

Optoelectronic properties of a novel fluorene derivative for organic light-emitting diode

Energy Technology Data Exchange (ETDEWEB)

Yu, Junsheng; Lou, Shuangling; Qian, Jincheng; Jiang, Yadong [University of Electronic Science and Technology of China (UESTC), State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Information, Chengdu (China); Zhang, Qing [Shanghai Jiaotong University, Department of Polymer Science, School of Chemistry and Chemical Technology, Shanghai (China)

2009-03-15

We report the optoelectronic properties of a novel fluorene derivative of 6,6'-(9H-fluoren-9,9-diyl)bis(2,3-bis (9,9-dihexyl-9H-fluoren-2-yl)quinoxaline) (BFLBBFLYQ) used for organic light-emitting diode. UV-Vis absorption, photoluminescence (PL) and electroluminescence (EL) spectra of BFLBBFLYQ and the blend doped with N,N'-biphenyl-N,N'-bis-(3-methylphenyl)-1,1'-biphenyl-4,4'-di- amine (TPD) in solid state and in solution were investigated. The results showed that BFLBBFLYQ had a PL peak at 451 nm in solid and solution states and an EL peak at 483 nm with a broad emission band, resulting from fluorenone defects. Exciplex emission was observed in BFLBBFLYQ-TPD blend solid state with a green emission peaking at 530 nm. Also the blend in solution showed solvatochromism in polarity solvent upon UV irradiation. A new absorption band appeared at around 470 nm of BFLBBFLYQ-TPD blend in chloroform solution, and disappeared when diluted in absorption spectrum. Meanwhile, a low energy emission band from 530 to 580 nm appeared and increased with material concentration and UV irradiation time. (orig.)

SPHINGOMONAS PAUCIMOBILIS INFECTIONS IN CHILDREN: NOSOCOMIAL VERSUS COMMUNITY ACQUIRED INFECTIONS

Directory of Open Access Journals (Sweden)

Nuri Bayram

2013-06-01

Full Text Available Sphingomonas paucimobilis is a causative agent of infection in immunocompromised patients, and healthcare-associated infections. Although the infections associated with S.paucimobilis occurs rarely, it has been encountered with increasing frequency in clinical settings. In the current study we noted the risk factors and clinical features of the children with S.paucimobilis infections, and the antimicrobial susceptibilities of the isolated strains among the patients. This study was conducted in Dr. Behçet Uz Children’s Hospital, Turkey, during the period of January 2005 and December 2012. The medical records of pediatric patients with positive cultures for S.paucimobilis were reviewed. Sphingomonas paucimobilis isolates were recovered from 24 pediatric patients. The median age was 4 years (ranging from 3 days infant to 15 years and 58,3% were male. Eight (33,3% of the patients were under 1 months of age. Among the patients; 13 (54,2% infections were community related however 11(45.8% infections were nosocomial infection. The median duration of hospital stay was 7 days (ranging from 4 to 22 days. The most effective antibiotics were fluoroquinolones, carbapenems, and trimethoprim/sulfamethoxazole. This is the first largest study in children to evaluate the clinical features of S. paucimobilis infections. Sphingomonas paucimobilis may cause infections in both previously healthy and immunocompromised children. Although variable antimicrobial regimens were achieved to the patients, there was no attributable fatality due to S.paucimobilis infections due to the low virulence of the bacteria.

Vectorial photoinduced energy transfer between boron-dipyrromethene (Bodipy) chromophores across a fluorene bridge.

Science.gov (United States)

Puntoriero, Fausto; Nastasi, Francesco; Campagna, Sebastiano; Bura, Thomas; Ziessel, Raymond

2010-08-02

A series of novel multichromophoric, luminescent compounds has been prepared, and their absorption spectra, luminescence properties (both at 77 K in rigid matrix and at 298 K in fluid solution), and photoinduced intercomponent energy-transfer processes have been studied. The series contains two new multichromophoric systems 1 and 2, each one containing two different boron-dipyrromethene (Bodipy) subunits and one bridging fluorene species, and two fluorene-Bodipy bichromophoric species, 6 and 7. Three monochromophoric compounds, 3, 4, and 5, used as precursors in the synthetic process, were also fully characterized. The absorption spectra of the multichromophoric compounds are roughly the summation of the absorption spectra of their individual components, thus demonstrating the supramolecular nature of the assemblies. Luminescence studies show that quantitative energy transfer occurs in 6 and 7 from the fluorene chromophore to the Bodipy dyes. Luminescence studies, complemented by transient-absorption spectroscopy studies, also indicate that efficient inter-Bodipy energy transfer across the rigid fluorene spacer takes place in 1 and 2, with rate constants, evaluated by several experimental methods, between 2.0 and 7.0 x 10(9) s(-1). Such an inter-Bodipy energy transfer appears to be governed by the Förster mechanism. By taking advantage of the presence of various protonable sites in the substituents of the lower-energy Bodipy subunit of 1 and 2, the effect of protonation on the energy-transfer rates has also been investigated. The results suggest that control of energy-transfer rate and efficiency of inter-Bodipy energy transfer in this type of systems can be achieved by an external, reversible input.

Degradation of some representative polycyclic aromatic hydrocarbons by the water-soluble protein extracts from Zea mays L. cv PR32-B10.

Science.gov (United States)

Barone, Roberto; de Biasi, Margherita-Gabriella; Piccialli, Vincenzo; de Napoli, Lorenzo; Oliviero, Giorgia; Borbone, Nicola; Piccialli, Gennaro

2016-10-01

The ability of the water-soluble protein extracts from Zea mais L. cv. PR32-B10 to degrade some representative polycyclic aromatic hydrocarbons (PAHs), has been evaluated. Surface sterilized seeds of corn (Zea mais L. Pioneer cv. PR32-B10) were hydroponically cultivated in a growth chamber under no-stressful conditions. The water-soluble protein extracts isolated from maize tissues showed peroxidase, polyphenol oxidase and catalase activities. Incubation of the extracts with naphthalene, fluorene, phenanthrene and pyrene, led to formation of oxidized and/or degradation products. GC-MS and TLC monitoring of the processes showed that naphthalene, phenanthrene, fluorene and pyrene underwent 100%, 78%, 92% and 65% oxidative degradation, respectively, after 120 min. The chemical structure of the degradation products were determined by (1)H NMR and ESI-MS spectrometry. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biodegradation of phenanthrene in artificial seawater by using free ...

African Journals Online (AJOL)

and related aromatic compounds. This paper reports the domestication of strain Sphingomonas sp. GY2B in artificial seawater (AS) and the immobilization of the strain onto rice straw. Results showed that adding 85% artificial seawater had very low impact on the growth and phenanthrene degradation ability of strain GY2B ...

Identification of anthraquinone-degrading bacteria in soil contaminated with polycyclic aromatic hydrocarbons.

Science.gov (United States)

Rodgers-Vieira, Elyse A; Zhang, Zhenfa; Adrion, Alden C; Gold, Avram; Aitken, Michael D

2015-06-01

Quinones and other oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) are toxic and/or genotoxic compounds observed to be cocontaminants at PAH-contaminated sites, but their formation and fate in contaminated environmental systems have not been well studied. Anthracene-9,10-dione (anthraquinone) has been found in most PAH-contaminated soils and sediments that have been analyzed for oxy-PAHs. However, little is known about the biodegradation of oxy-PAHs, and no bacterial isolates have been described that are capable of growing on or degrading anthraquinone. PAH-degrading Mycobacterium spp. are the only organisms that have been investigated to date for metabolism of a PAH quinone, 4,5-pyrenequinone. We utilized DNA-based stable-isotope probing (SIP) with [U-(13)C]anthraquinone to identify bacteria associated with anthraquinone degradation in PAH-contaminated soil from a former manufactured-gas plant site both before and after treatment in a laboratory-scale bioreactor. SIP with [U-(13)C]anthracene was also performed to assess whether bacteria capable of growing on anthracene are the same as those identified to grow on anthraquinone. Organisms closely related to Sphingomonas were the most predominant among the organisms associated with anthraquinone degradation in bioreactor-treated soil, while organisms in the genus Phenylobacterium comprised the majority of anthraquinone degraders in the untreated soil. Bacteria associated with anthracene degradation differed from those responsible for anthraquinone degradation. These results suggest that Sphingomonas and Phenylobacterium species are associated with anthraquinone degradation and that anthracene-degrading organisms may not possess mechanisms to grow on anthraquinone. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Degradation of carbazole, dibenzothiophene, and dibenzofuran at low temperature by Pseudomonas sp. strain C3211.

Science.gov (United States)

Jensen, Anne-Mette; Finster, Kai Waldemar; Karlson, Ulrich

2003-04-01

Pseudomonas sp. strain C3211 was isolated from a temperate climate soil contaminated with creosote. This strain was able to degrade carbazole, dibenzothiophene and dibenzofuran at 10 degrees C with acetone as a co-substrate. When dibenzothiophene was degraded by strain C3211, an orange compound, which absorbed at 472 nm, accumulated in the medium. Degradation of dibenzofuran was followed by accumulation of a yellowish compound, absorbing at 462 nm. The temperature optimum of strain C3211 for degradation of dibenzothiophene and dibenzofuran was at 20 to 21 degrees C, while the maximum temperature for degradation was at 27 degrees C. Both compounds were degraded at 4 degrees C. Degradation at 10 degrees C was faster than degradation at 25 degrees C. This indicates that strain C3211 is adapted to life at low temperatures.

AcEST: DK959014 [AcEST

Lifescience Database Archive (English)

Full Text Available inition sp|Q7X2N3|SYV_SPHEL Valyl-tRNA synthetase OS=Sphingomonas elodea Align length 46 Score (bit) 31.6 E-... Value sp|Q7X2N3|SYV_SPHEL Valyl-tRNA synthetase OS=Sphingomonas elodea... 32 3.7...is protein 1 OS=Bacillus phage B... 30 8.2 >sp|Q7X2N3|SYV_SPHEL Valyl-tRNA synthetase OS=Sphingomonas elodea

Degradation and metabolism of synthetic plastics and associated products by Pseudomonas sp.: capabilities and challenges.

Science.gov (United States)

Wilkes, R A; Aristilde, L

2017-09-01

Synthetic plastics, which are widely present in materials of everyday use, are ubiquitous and slowly-degrading polymers in environmental wastes. Of special interest are the capabilities of microorganisms to accelerate their degradation. Members of the metabolically diverse genus Pseudomonas are of particular interest due to their capabilities to degrade and metabolize synthetic plastics. Pseudomonas species isolated from environmental matrices have been identified to degrade polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyurethane, polyethylene terephthalate, polyethylene succinate, polyethylene glycol and polyvinyl alcohol at varying degrees of efficiency. Here, we present a review of the current knowledge on the factors that control the ability of Pseudomonas sp. to process these different plastic polymers and their by-products. These factors include cell surface attachment within biofilms, catalytic enzymes involved in oxidation or hydrolysis of the plastic polymer, metabolic pathways responsible for uptake and assimilation of plastic fragments and chemical factors that are advantageous or inhibitory to the biodegradation process. We also highlight future research directions required in order to harness fully the capabilities of Pseudomonas sp. in bioremediation strategies towards eliminating plastic wastes. © 2017 The Society for Applied Microbiology.

The endophytic bacterium Serratia sp. PW7 degrades pyrene in wheat.

Science.gov (United States)

Zhu, Xuezhu; Wang, Wanqing; Crowley, David E; Sun, Kai; Hao, Shupeng; Waigi, Michael Gatheru; Gao, Yanzheng

2017-03-01

This research was conducted to isolate polycyclic aromatic hydrocarbon-degrading (PAH-degrading) endophytic bacteria and investigate their potential in protecting plants against PAH contamination. Pyrene-degrading endophytic bacteria were isolated from plants grown in PAH-contaminated soil. Among these endophytic bacteria, strain PW7 (Serratia sp.) isolated from Plantago asiatica was selected to investigate the suppression of pyrene accumulation in Triticum aestivum L. In the in vitro tests, strain PW7 degraded 51.2% of the pyrene in the media within 14 days. The optimal biodegradation conditions were pH 7.0, 30 °C, and MS medium supplemented with additional glucose, maltose, sucrose, and peptones. In the in vivo tests, strain PW7 successfully colonized the roots and shoots of inoculated (E + ) wheat plants, and its colonization decreased pyrene accumulation and pyrene transportation from roots to shoots. Remarkably, the concentration of pyrene in shoots decreased much more than that in roots, suggesting that strain PW7 has the potential for protecting wheat against pyrene contamination and mitigating the threat of pyrene to human health via food consumption.

Degradation of 3-phenoxybenzoic acid by a Bacillus sp.

Directory of Open Access Journals (Sweden)

Shaohua Chen

Full Text Available 3-Phenoxybenzoic acid (3-PBA is of great environmental concern with regards to endocrine disrupting activity and widespread occurrence in water and soil, yet little is known about microbial degradation in contaminated regions. We report here that a new bacterial strain isolated from soil, designated DG-02, was shown to degrade 95.6% of 50 mg·L(-1 3-PBA within 72 h in mineral salt medium (MSM. Strain DG-02 was identified as Bacillus sp. based on the morphology, physio-biochemical tests and 16S rRNA sequence. The optimum conditions for 3-PBA degradation were determined to be 30.9°C and pH 7.7 using response surface methodology (RSM. The isolate converted 3-PBA to produce 3-(2-methoxyphenoxy benzoic acid, protocatechuate, phenol, and 3,4-dihydroxy phenol, and subsequently transformed these compounds with a q(max, K(s and K(i of 0.8615 h(-1, 626.7842 mg·L(-1 and 6.7586 mg·L(-1, respectively. A novel microbial metabolic pathway for 3-PBA was proposed on the basis of these metabolites. Inoculation of strain DG-02 resulted in a higher degradation rate on 3-PBA than that observed in the non-inoculated soil. Moreover, the degradation process followed the first-order kinetics, and the half-life (t(1/2 for 3-PBA was greatly reduced as compared to the non-inoculated control. This study highlights an important potential application of strain DG-02 for the in situ bioremediation of 3-PBA contaminated environments.

Inoculation of soil with an Isoproturon degrading microbial community reduced the pool of "real non-extractable" Isoproturon residues.

Science.gov (United States)

Zhu, Xiaomin; Schroll, Reiner; Dörfler, Ulrike; Chen, Baoliang

2018-03-01

During pesticides degradation, biogenic non-extractable residues ("apparent NER") may not share the same environmental fate and risks with the "real NER" that are bound to soil matrix. It is not clear how microbial community (MC) inoculation for pesticides degradation would influence the NER composition. To investigate degradation efficiency of pesticides Isoproturon (IPU) and NER composition following MC inoculation, clay particles harboring MC that contains the IPU degrading strain, Sphingomonas sp., were inoculated into soil receiving 14 C-labeled IPU addition. Mineralization of IPU was greatly enhanced with MC inoculation that averagely 55.9% of the applied 14 C-IPU was consumed up into 14 CO 2 during 46 days soil incubation. Isoproturon degradation was more thorough with MC than that in the control: much less amount of metabolic products (4.6% of applied IPU) and NER (35.4%) formed in MC treatment, while the percentages were respectively 30.3% for metabolites and 49.8% for NER in the control. Composition of NER shifted with MC inoculation, that relatively larger amount of IPU was incorporated into the biogenic "apparent NER" in comparison with "real NER". Besides its well-recognized role on enhancing mineralization, MC inoculation with clay particles benefits soil pesticides remediation in term of reducing "real NER" formation, which has been previously underestimated. Copyright © 2017 Elsevier Inc. All rights reserved.

Immobilization of Bacillus sp. in mesoporous activated carbon for degradation of sulphonated phenolic compound in wastewater.

Science.gov (United States)

Sekaran, G; Karthikeyan, S; Gupta, V K; Boopathy, R; Maharaja, P

2013-03-01

Xenobiotic compounds are used in considerable quantities in leather industries besides natural organic and inorganic compounds. These compounds resist biological degradation and thus they remain in the treated wastewater in the unaltered molecular configurations. Immobilization of organisms in carrier matrices protects them from shock load application and from the toxicity of chemicals in bulk liquid phase. Mesoporous activated carbon (MAC) has been considered in the present study as the carrier matrix for the immobilization of Bacillus sp. isolated from Effluent Treatment Plant (ETP) employed for the treatment of wastewater containing sulphonated phenolic (SP) compounds. Temperature, pH, concentration, particle size and mass of MAC were observed to influence the immobilization behavior of Bacillus sp. The percentage immobilization of Bacillus sp. was the maximum at pH 7.0, temperature 20 °C and at particle size 300 μm. Enthalpy, free energy and entropy of immobilization were -46.9 kJ mol(-1), -1.19 kJ mol(-1) and -161.36 JK(-1)mol(-1) respectively at pH 7.0, temperature 20 °C and particle size 300 μm. Higher values of ΔH(0) indicate the firm bonding of the Bacillus sp. in MAC. Degradation of aqueous sulphonated phenolic compound by Bacillus sp. immobilized in MAC followed pseudo first order rate kinetics with rate constant 1.12 × 10(-2) min(-1). Copyright © 2012 Elsevier B.V. All rights reserved.

Continuous degradation of trichloroethylene by Xanthobacter sp. strain Py2 during growth on propene.

OpenAIRE

Reij, M W; Kieboom, J; de Bont, J A; Hartmans, S

1995-01-01

Propene-grown Xanthobacter sp. strain Py2 cells can degrade trichloroethylene (TCE), but the transformation capacity of such cells was limited and depended on both the TCE concentration and the biomass concentration. Toxic metabolites presumably accumulated extracellularly, because the fermentation of glucose by yeast cells was inhibited by TCE degradation products formed by strain Py2. The affinity of the propene monooxygenase for TCE was low, and this allowed strain Py2 to grow on propene i...

Monooxygenase, a novel beta-cypermethrin degrading enzyme from Streptomyces sp.

Directory of Open Access Journals (Sweden)

Shaohua Chen

Full Text Available The widely used insecticide beta-cypermethrin has become a public concern because of its environmental contamination and toxic effects on mammals. In this study, a novel beta-cypermethrin degrading enzyme designated as CMO was purified to apparent homogeneity from a Streptomyces sp. isolate capable of utilizing beta-cypermethrin as a growth substrate. The native enzyme showed a monomeric structure with a molecular mass of 41 kDa and pI of 5.4. The enzyme exhibited the maximal activity at pH 7.5 and 30°C. It was fairly stable in the pH range from 6.5-8.5 and at temperatures below 10°C. The enzyme activity was significantly stimulated by Fe(2+, but strongly inhibited by Ag(+, Al(3+, and Cu(2+. The enzyme catalyzed the degradation of beta-cypermethrin to form five products via hydroxylation and diaryl cleavage. A novel beta-cypermethrin detoxification pathway was proposed based on analysis of these products. The purified enzyme was identified as a monooxygenase by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry analysis (MALDI-TOF-MS and N-terminal protein sequencing. Given that all the characterized pyrethroid-degrading enzymes are the members of hydrolase family, CMO represents the first pyrethroid-degrading monooxygenase identified from environmental microorganisms. Taken together, our findings depict a novel pyrethroid degradation mechanism and indicate that the purified enzyme may be a promising candidate for detoxification of beta-cypermethrin and environmental protection.

Formulation of economical microbial feed using degraded chicken feathers by a novel Streptomyces sp: mitigation of environmental pollution

Directory of Open Access Journals (Sweden)

Jayapradha Ramakrishnan

2011-09-01

Full Text Available A new Streptomyces sp. IF 5 was isolated from the feather dumped soil and found to have a tremendous keratinase activity. The strain enabled the degradation of the chicken feathers very effectively in 60 h. The 16S rRNA sequence of 1474 bp long was submitted to the National centre for Biotechnological information. The keratinolytic activity in the culture medium was 1181 U/ml. The release and analyses of sulphydryl groups in the culture medium evident the degradation activity by the Streptomyces sp. IF 5. The idea of the present study was to use the degraded chicken feathers as the substrate for the growth and cultivation of microorganisms. We have designed a very economical culture medium that includes the usage of some basal salts alone and degraded chicken feathers (10 g/l. The results of the specific growth rate of the tested microbes confirm the usage of the new designed medium for microbial culturing.

[Isolation, identification and characterization of a diethylstilbestrol-degrading bacterial strain Serratia sp].

Science.gov (United States)

Xu, Ran-Fang; Sun, Min-Xia; Liu, Juan; Wang, Hong; Li, Xin; Zhu, Xue-Zhu; Ling, Wan-Ting

2014-08-01

Utilizing the diethylstilbestrol (DES)-degrading bacteria to biodegrade DES is a most reliable technique for cleanup of DES pollutants from the environment. However, little information is available heretofore on the isolation of DES-degrading bacteria and their DES removal performance in the environment. A novel bacterium capable of degrading DES was isolated from the activated sludge of a wastewater treatment plant. According to its morphology, physiochemical characteristics, and 16S rDNA sequence analysis, this strain was identified as Serratia sp.. The strain was an aerobic bacterium, and it could degrade 68.3% of DES (50 mg x L(-1)) after culturing for 7 days at 30 degrees C, 150 r x min(-1) in shaking flasks. The optimal conditions for DES biodegradation by the obtained strain were 30 degrees C, 40-60 mg x L(-1) DES, pH 7.0, 5% of inoculation volume, 0 g x L(-1) of added NaCl, and 10 mL of liquid medium volume in 100 mL flask.

Polycyclic aromatic hydrocarbons (PAHs) biodegradation potential and diversity of microbial consortia enriched from tsunami sediments in Miyagi, Japan.

Science.gov (United States)

Bacosa, Hernando Pactao; Inoue, Chihiro

2015-01-01

The Great East Japan Earthquake caused tsunamis and resulted in widespread damage to human life and infrastructure. The disaster also resulted in contamination of the environment by chemicals such as polycyclic aromatic hydrocarbons (PAHs). This study was conducted to investigate the degradation potential and describe the PAH-degrading microbial communities from tsunami sediments in Miyagi, Japan. PAH-degrading bacteria were cultured by enrichment using PAH mixture or pyrene alone as carbon and energy sources. Among the ten consortia tested for PAH mixture, seven completely degraded fluorene and more than 95% of phenanthrene in 10 days, while only four consortia partially degraded pyrene. Six consortia partially degraded pyrene as a single substrate. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that each sample was dominated by unique microbial populations, regardless of sampling location. The consortia were dominated by known PAHs degraders including Sphingomonas, Pseudomonas, and Sphingobium; and previously unknown degraders such as Dokdonella and Luteimonas. A potentially novel and PAH-degrading Dokdonella was detected for the first time. PAH-ring hydroxylating dioxygenase (PAH-RHDα) gene was shown to be more effective than nidA in estimating pyrene-degrading bacteria in the enriched consortia. The consortia obtained in this study are potential candidates for remediation of PAHs contaminated soils. Copyright © 2014 Elsevier B.V. All rights reserved.

Femtosecond Two-Photon Absorption Spectroscopy of Poly(fluorene Derivatives Containing Benzoselenadiazole and Benzothiadiazole

Directory of Open Access Journals (Sweden)

Marcelo Gonçalves Vivas

2017-05-01

Full Text Available We have investigated the molecular structure and two-photon absorption (2PA properties relationship of two push–pull poly(fluorene derivatives containing benzoselenadiazole and benzothiadiazole units. For that, we have used the femtosecond wavelength-tunable Z-scan technique with a low repetition rate (1 kHz and an energy per pulse on the order of nJ. Our results show that both 2PA spectra present a strong 2PA (around 600 GM (1 GM = 1 × 10−50 cm4·s·photon−1 band at around 720 nm (transition energy 3.45 eV ascribed to the strongly 2PA-allowed 1Ag-like → mAg-like transition, characteristic of poly(fluorene derivatives. Another 2PA band related to the intramolecular charge transfer was also observed at around 900 nm (transition energy 2.75 eV. In both 2PA bands, we found higher 2PA cross-section values for the poly(fluorene containing benzothiadiazole unit. This outcome was explained through the higher charge redistribution at the excited state caused by the benzothiadiazole group as compared to the benzoselenadiazole and confirmed by means of solvatochromic Stokes shift measurements. To shed more light on these results, we employed the sum-over-states approach within the two-energy level model to estimate the maximum permanent dipole moment change related to the intramolecular charge transfer transition.

Degradation pathways of 1-methylphenanthrene in bacterial Sphingobium sp. MP9-4 isolated from petroleum-contaminated soil.

Science.gov (United States)

Zhong, Jianan; Luo, Lijuan; Chen, Baowei; Sha, Sha; Qing, Qing; Tam, Nora F Y; Zhang, Yong; Luan, Tiangang

2017-01-30

Alkylated polycyclic aromatic hydrocarbons (PAHs) are abundant in petroleum, and alkylated phenanthrenes are considered as the primary PAHs during some oil spill events. Bacterial strain of Sphingobium sp. MP9-4, isolated from petroleum-contaminated soil, was efficient to degrade 1-methylphenanthrene (1-MP). A detailed metabolism map of 1-MP in this strain was delineated based on analysis of metabolites with gas chromatograph-mass spectrometer (GC-MS). 1-MP was initially oxidized via two different biochemical strategies, including benzene ring and methyl-group attacks. Benzene ring attack was initiated with dioxygenation of the non-methylated aromatic ring via similar degradation pathways of phenanthrene (PHE) by bacteria. For methyl-group attack, mono oxygenase system was involved and more diverse enzymes were needed than that of PHE degradation. This study enhances the understanding of the metabolic pathways of alkylated PAHs and shows the significant potential of Sphingobium sp. MP9-4 for the bioremediation of alkylated PAHs contaminated environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Degradation/solubilization of Chinese lignite by Penicillium sp. P6

Energy Technology Data Exchange (ETDEWEB)

Yuan, H.L.; Yang, J.S.; Wang, F.Q.; Chen, W.X. [China Agricultural University, Beijing (China). Key Laboratory of Agro-Microbial Resource and Application, Ministry of Agrio, College of Biological Science

2006-01-15

Penicillium sp. P6, isolated from coal mine soil at the Qiantong colliery Liaoning Province, Northeast China, can degrade Chinese lignite in 36 h on a plate colony and in 48 h using a 4-day cultured cell-free filtrate. Results of elemental analysis and IR spectrometry indicated that solubilized products exhibited some alterations in comparison to the original lignite. The amount of fulvic acid extracted from the biodegraded lignite was high, and the molecular distribution of the humic acids from biodegraded lignite changed distinctively in comparison to which extracted from the control lignite, possibly due to the depolymerization associated with fungal biodegradation.

Successful bioaugmentation of an activated sludge reactor with Rhodococcus sp. YYL for efficient tetrahydrofuran degradation

International Nuclear Information System (INIS)

Yao, Yanlai; Lu, Zhenmei; Zhu, Fengxiang; Min, Hang; Bian, Caimiao

2013-01-01

Highlights: • Rhodococcus sp. YYL is an efficient tetrahydrofuran-degrading strain. • Strain YYL was used to augment an activated sludge system for THF degradation. • Successful bioaugmentation was achieved only by coinoculation of strain YYL and the two bacilli. • Successful bioaugmentation of the system resulted in efficient THF degradation. -- Abstract: The exchange of tetrahydrofuran (THF)-containing wastewater should significantly affect the performance of an activated sludge system. In this study, the feasibility of using THF-degrading Rhodococcus sp. strain YYL to bioaugment an activated sludge system treating THF wastewater was explored. As indicated by a DGGE analysis, strain YYL alone could not dominate the system, with the concentration of mixed liquor suspended solids (MLSS) decreasing to nearly half of the initial concentration after 45 d, and the microbial diversity was found to be significantly reduced. However, after the reactor was augmented with the mixed culture of strain YYL and two bacilli initially coexisting in the enriched isolation source, strain YYL quickly became dominant in the system and was incorporated into the activated sludge. The concentration of MLSS increased from 2.1 g/L to 7.3 g/L in 20 d, and the efficiency of THF removal from the system was remarkably improved. After the successful bioaugmentation, more than 95% of THF was completely removed from the wastewater when 20 mM THF was continuously loaded into the system. In conclusion, our research first demonstrates that bioaugmentation of activated sludge system for THF degradation is feasible but that successful bioaugmentation should utilize a THF-degrading mixed culture as the inoculum, in which the two bacilli might help strain YYL colonize in activated sludge by co-aggregation

Genome-Wide Analysis of Salicylate and Dibenzofuran Metabolism in Sphingomonas wittichii RW1

Directory of Open Access Journals (Sweden)

Edith eCoronado

2012-08-01

Full Text Available Sphingomonas wittichii RW1 is a bacterium isolated for its ability to degrade the xenobiotic compounds dibenzodioxin and dibenzofuran (DBF. A number of genes involved in DBF degradation have been previously characterized, such as the dxn cluster, dbfB, and the electron transfer components fdx1, fdx3 and redA2. Here we use a combination of whole genome transcriptome analysis and transposon library screening to characterize RW1 catabolic and other genes implicated in the reaction to or degradation of DBF. To detect differentially expressed genes upon exposure to DBF, we applied three different growth exposure experiments, using either short DBF exposures to actively growing cells or growing them with DBF as sole carbon and energy source. Genome-wide gene expression was examined using a custom-made microarray. In addition, proportional abundance determination of transposon insertions in RW1 libraries grown on salicylate or DBF by ultra-high throughput sequencing was used to infer genes whose interruption caused a fitness loss for growth on DBF. Expression patterns showed that batch and chemostat growth conditions, and short or long exposure of cells to DBF produced very different responses. Numerous other uncharacterized catabolic gene clusters putatively involved in aromatic compound metabolism increased expression in response to DBF. In addition, only very few transposon insertions completely abolished growth on DBF. Some of those (e.g., in dxnA1 were expected, whereas others (in a gene cluster for phenylacetate degradation were not. Both transcriptomic data and transposon screening suggest operation of multiple redundant and parallel aromatic pathways, depending on DBF exposure. In addition, increased expression of other non-catabolic genes suggests that during initial exposure, S. wittichii RW1 perceives DBF as a stressor, whereas after longer exposure, the compound is recognized as a carbon source and metabolized using several pathways in

Identification of a 4-Deoxy-l-erythro-5-hexoseulose Uronic Acid Reductase, FlRed, in an Alginolytic Bacterium Flavobacterium sp. Strain UMI-01

Directory of Open Access Journals (Sweden)

Akira Inoue

2015-01-01

Full Text Available In alginate-assimilating bacteria, alginate is depolymerized to unsaturated monosaccharide by the actions of endolytic and exolytic alginate lyases (EC 4.2.2.3 and EC 4.2.2.11. The monosaccharide is non-enzymatically converted to 4-deoxy-l-ery thro-5-hexoseulose uronic acid (DEH, then reduced to 2-keto-3-deoxy-d-gluconate (KDG by a specific reductase, and metabolized through the Entner–Doudoroff pathway. Recently, the NADPH-dependent reductase A1-R that belongs to short-chain dehydrogenases/reductases (SDR superfamily was identified as the DEH-reductase in Sphingomonas sp. A1. We have subsequently noticed that an SDR-like enzyme gene, flred, occurred in the genome of an alginolytic bacterium Flavobacterium sp. strain UMI-01. In the present study, we report on the deduced amino-acid sequence of flred and DEH-reducing activity of recombinant FlRed. The deduced amino-acid sequence of flred comprised 254 residues and showed 34% amino-acid identities to that of A1-R from Sphingomonas sp. A1 and 80%–88% to those of SDR-like enzymes from several alginolytic bacteria. Common sequence motifs of SDR-superfamily enzymes, e.g., the catalytic tetrad Asn-Lys-Tyr-Ser and the cofactor-binding sequence Thr-Gly-x-x-x-Gly-x-Gly in Rossmann fold, were completely conserved in FlRed. On the other hand, an Arg residue that determined the NADPH-specificity of Sphingomonas A1-R was replaced by Glu in FlRed. Thus, we investigated cofactor-preference of FlRed using a recombinant enzyme. As a result, the recombinant FlRed (recFlRed was found to show high specificity to NADH. recFlRed exhibited practically no activity toward variety of aldehyde, ketone, keto ester, keto acid and aldose substrates except for DEH. On the basis of these results, we conclude that FlRed is the NADH-dependent DEH-specific SDR of Flavobacterium sp. strain UMI-01.

Polycyclic aromatic hydrocarbon-contaminated soils: bioaugmentation of autochthonous bacteria and toxicological assessment of the bioremediation process by means of Vicia faba L.

Science.gov (United States)

Ruffini Castiglione, Monica; Giorgetti, Lucia; Becarelli, Simone; Siracusa, Giovanna; Lorenzi, Roberto; Di Gregorio, Simona

2016-04-01

Two bacterial strains, Achromobacter sp. (ACH01) and Sphingomonas sp. (SPH01), were isolated from a heavily polycyclic aromatic hydrocarbon (PAH)-contaminated soil (5431.3 ± 102.3 ppm) for their capacity to use a mixture of anthracene, pyrene, phenanthrene and fluorene as sole carbon sources for growth and for the capacity to produce biosurfactants. The two strains were exploited for bioaugmentation in a biopile pilot plant to increase the bioavailability and the degradation of the residual PAH contamination (99.5 ± 7.1 ppm) reached after 9 months of treatment. The denaturing gel gradient electrophoresis (DGGE) profile of the microbial ecology of the soil during the experimentation showed that the bioaugmentation approach was successful in terms of permanence of the two strains in the soil in treatment. The bioaugmentation of the two bacterial isolates positively correlated with the PAH depletion that reached 7.9 ± 2 ppm value in 2 months of treatment. The PAH depletion was assessed by the loss of the phyto-genotoxicity of soil elutriates on the model plant Vicia faba L., toxicological assessment adopted also to determine the minimum length of the decontamination process for obtaining both the depletion of the PAH contamination and the detoxification of the soil at the end of the process. The intermediate phases of the bioremediation process were the most significant in terms of toxicity, inducing genotoxic effects and selective DNA fragmentation in the stem cell niche of the root tip. The selective DNA fragmentation can be related to the selective induction of cell death of mutant stem cells that can compromise offsprings.

NCBI nr-aa BLAST: CBRC-DDIS-02-0191 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-DDIS-02-0191 ref|ZP_01302230.1| putative manganese transport protein MntH [Sph...ingomonas sp. SKA58] gb|EAT10059.1| putative manganese transport protein MntH [Sphingomonas sp. SKA58] ZP_01302230.1 1e-71 50% ...

NCBI nr-aa BLAST: CBRC-AGAM-07-0044 [SEVENS

Lifescience Database Archive (English)

Full Text Available CBRC-AGAM-07-0044 ref|ZP_01302230.1| putative manganese transport protein MntH [Sph...ingomonas sp. SKA58] gb|EAT10059.1| putative manganese transport protein MntH [Sphingomonas sp. SKA58] ZP_01302230.1 1e-100 52% ...

Synthesis of Dendrimer Containing Dialkylated-fluorene Unit as a Core Chromophore via Click Chemistry

International Nuclear Information System (INIS)

Han, Seung Choul; Lee, Jae Wook; Jin, Sung Ho

2012-01-01

The convergent synthetic strategy for the emissive dendrimers having the chromophore at core via the coppercatalyzed 1,3-dipolar cycloaddition reaction between alkyne and azide was described. 2,7-Diazido-9,9-dioctyl- 9H-fluorene, designed to serve as the core in dendrimer, was stitched with the alkyne-functionalized Frechettype and PAMAM dendrons by the click chemistry leading to the formation of the corresponding fluorescent dendrimers in high yields. The preliminary photoluminescence studies indicated that 2,7-diazido-9,9-dioctyl- 9H-fluorene showed no fluorescence due to the quenching effect from the electron-rich α-nitrogen of the azido group but the dendrimers fluoresced due to the elimination of the quenching through the formation of the triazole ring

Scalable synthesis of 5,11-diethynylated indeno[1,2-b]fluorene-6,12-diones and exploration of their solid state packing

Directory of Open Access Journals (Sweden)

Bradley D. Rose

2014-09-01

Full Text Available We report a new synthetic route to 5,11-disubstituted indeno[1,2-b]fluorene-6,12-diones that is amenable to larger scale reactions, allowing for the preparation of gram amounts of material. With this new methodology, we explored the effects on crystal packing morphology for the indeno[1,2-b]fluorene-6,12-diones by varying the substituents on the silylethynyl groups.

Isolation of the opdE gene that encodes for a new hydrolase of Enterobacter sp. capable of degrading organophosphorus pesticides.

Science.gov (United States)

Chino-Flores, Concepción; Dantán-González, Edgar; Vázquez-Ramos, Alejandra; Tinoco-Valencia, Raunel; Díaz-Méndez, Rafael; Sánchez-Salinas, Enrique; Castrejón-Godínez, Maria Luisa; Ramos-Quintana, Fernando; Ortiz-Hernández, Maria Laura

2012-06-01

Microbial enzymes that can hydrolyze organophosphorus compounds have been isolated, identified and characterized from different microbial species in order to use them in biodegradation of organophosphorus compounds. We isolated a bacterial strain Cons002 from an agricultural soil bacterial consortium, which can hydrolyze methyl-parathion (MP) and other organophosphate pesticides. HPLC analysis showed that strain Cons002 is capable of degrading pesticides MP, parathion and phorate. Pulsed-field gel electrophoresis and 16S rRNA amplification were performed for strain characterization and identification, respectively, showing that the strain Cons002 is related to the genus Enterobacter sp. which has a single chromosome of 4.6 Mb and has no plasmids. Genomic library was constructed from DNA of Enterobacter sp. Cons002. A gene called opdE (Organophosphate Degradation from Enterobacter) consists of 753 bp and encodes a protein of 25 kDa, which was isolated using activity methods. This gene opdE had no similarity to any genes reported to degrade organophosphates. When kanamycin-resistance cassette was placed in the gene opdE, hydrolase activity was suppressed and Enterobacter sp. Cons002 had no growth with MP as a nutrients source.

Draft Genome Sequence of Sphingopyxis sp. Strain MWB1, a Crude-Oil-Degrading Marine Bacterium

Science.gov (United States)

Kim, Jonghyun; Kim, Soo Jung; Kim, Seon Hee; Kim, Seung Il; Moon, Yoon-Jung; Park, Sung-Joon

2014-01-01

Sphingopyxis sp. strain MWB1, which is capable of degrading crude oil, diesel, and kerosene, was isolated from crude oil–contaminated seashore in Tae-an, South Korea. Here, we report the draft genome sequence of this strain, which comprises 3,118,428 bp with a G+C content of 62.85 mol%. PMID:25477411

Enhanced production of dimethyl phthalate-degrading strain Bacillus sp. QD14 by optimizing fermentation medium

Directory of Open Access Journals (Sweden)

Jixian Mo

2015-05-01

Conclusion: In this work, the key factors affected by the fermentation of DMP-degrading strain Bacillus sp. QD14 were optimized by PBD, SAM and BBD (RSM; the yield was increased by 57,11% in the conditions in our study. We propose that the conditions optimized in the study can be applied to the fermentation for commercialization production.

Degradation of polyisoprene rubber by newly isolated Bacillus sp. AF-666 from soil.

Science.gov (United States)

Shah, A A; Hasan, F; Shah, Z; Mutiullah; Hameed, A

2012-01-01

Various microorganisms were screened for their ability to degrade polyisoprene rubber (natural rubber latex gloves). Strain AF-666, newly isolated from a soil sample, was selected as the best strain having the ability to grow on polyisoprene containing plates. The strain identified as Bacillus sp. AF-666, was found to degrade polyisoprene rubber, both on basal agar plates (latex overlay) as well as in liquid medium. Qualitative analysis of degradation was done through scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy SEM showed changes in surface morphology, like appearance of pits and cracks, and marked difference in transmittance spectra of test and control due to changes in the functional groups, was detected through FTIR. CO2 evolution as a result of rubber degradation, was calculated gravimetrically by Sturm Test. About 4.43 g/1 of CO2 was produced in case of test, whereas, 1.57 g/1 in case of control. The viable number of cells (CFU/ml) was also higher in test than in control. Present study may provide an opportunity for further studies on the applications of biotechnological processes as a tool for rubber waste management.

Isolation and characterization of a novel 2-methyl-4-chlorophenoxyacetic acid-degrading Enterobacter sp. strain SE08.

Science.gov (United States)

Tan, Lin; Hu, Qiulong; Xiong, Xingyao; Su, Xiaojun; Huang, Yanning; Jiang, Ziwei; Zhou, Qingming; Zhao, Songyi; Zeng, Wei-ai

2013-10-01

A bacterial strain (SE08) capable of utilizing 2-methyl-4-chlorophenoxy acetic acid (MCPA) as the sole carbon and energy source for growth was isolated by continuous enrichment culturing in minimal salt medium (MSM) from a long term MCPA exposed soil. This bacterial strain was identified as Enterobacter sp. based on morphological, physiological and biochemical tests, as well as 16S rRNA sequence analysis. Its ability to degrade MCPA was determined using high performance liquid chromatography. The strain SE08 can tolerate unusually high MCPA concentrations (125-2000mg/L). The influences of culturing factors (initial concentration, pH, and temperature) on the bacterial growth and substrate degradation were studied. The results showed that the optimal MCPA degradation occurred at an MCPA concentration of 500mg/L, 30°C and pH 6.0. Under these conditions, 68.5 percent of MCPA in MSM was degraded by SE08, and the OD600nm reached 0.64 after culturing for 72h. The degradation of MCPA could be enhanced by addition of both carbon and nitrogen sources. At an initial MCPA concentration of 500mg/L, when 5g/L glucose and 2.5g/L yeast extract were added into the MSM media, the MCPA degradation was significantly increased to 83.8 percent, and OD600nm was increased to 1.09 after incubation at 30°C and pH 6.0 for 72h. This is the first study showing that an Enterobacter sp. strain is capable of degrading MCPA, which might provide a new approach for the remediation of MCPA contaminated soil and contribute to the limited knowledge about the function of Enterobacter species. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

The synthesis, structure, and properties of 5,6,11,12-tetraarylindeno[1,2-b]fluorenes and their applications as donors for organic photovoltaic devices

KAUST Repository

Lo, Yuan-Chih; Ting, Hao-Chun; Li, Ya-Ze; Li, Yi-Hua; Liu, Shun-Wei; Huang, Kuo-Wei; Wong, Ken-Tsung

2016-01-01

The synthesis, structure, and properties of three new 5,6,11,12-tetraarylindeno[1,2-b]fluorenes are reported. The highly twisted conformations between an indeno[1,2-b]fluorene core and peripheral aryl substitutions endow these indeno[1,2-b]fluorene derivatives with good photostability for use as electron donors for vacuum-deposited photovoltaic devices. The optimized device based on a TAInF2 donor blended with C70 as an electron acceptor produces a high open-circuit voltage (>0.9 V) and a power conversion efficiency of 2.91%. This work demonstrates the first application of an indenofluorene derivative as an electron donor in organic solar cells.

The synthesis, structure, and properties of 5,6,11,12-tetraarylindeno[1,2-b]fluorenes and their applications as donors for organic photovoltaic devices

KAUST Repository

Lo, Yuan-Chih

2016-12-01

The synthesis, structure, and properties of three new 5,6,11,12-tetraarylindeno[1,2-b]fluorenes are reported. The highly twisted conformations between an indeno[1,2-b]fluorene core and peripheral aryl substitutions endow these indeno[1,2-b]fluorene derivatives with good photostability for use as electron donors for vacuum-deposited photovoltaic devices. The optimized device based on a TAInF2 donor blended with C70 as an electron acceptor produces a high open-circuit voltage (>0.9 V) and a power conversion efficiency of 2.91%. This work demonstrates the first application of an indenofluorene derivative as an electron donor in organic solar cells.

Degradation of phenolic acids and relief of consecutive monoculture obstacle of rehmannia glutinosa by the combination of bacillus sp. and pichia pastoris

International Nuclear Information System (INIS)

Wang, R.; Miao, Y.; Kang, C.

2017-01-01

Rehmannia glutinosa (R. glutinosa) is a high demand traditional Chinese medicine, but it suffers serious consecutive monoculture obstacle (CMO). The disability of root swelling is one of the negative impacts caused by the R. glutinosa CMO and is related to allelopathy exudates, such as phenolic acids. It is thought that a microbe agent could improve plant health by eliminating the unfavorable effect of allelopathy exudates. In previous research, we isolated two phenolic acid-degrading microbes from rhizosphere soil surrounding R. glutinosa. These were Bacillus sp. and Pichia pastoris. This study found that Bacillus sp. combined with Pichia pastoris could degrade 97.19% ferulic acid and 98.73% hydroxybenzoic acid over 15 days. R. glutinosa takes a long growth time (7-8 months) under field conditions. We set up a modified tissue culture model to rapidly detect whether Bacillus sp. and Pichia pastoris combination could relieve the CMO. The results showed that our tissue culture model effectively simulated the R. glutinosa growing process in unplanted or second-year monoculture field. Furthermore, the combination of Bacillus sp. and Pichia pastoris can significantly relieve the CMO-induced suppression of root swelling. All these results suggested that: 1) The combination of Bacillus sp. and Pichia pastoris has considerable potential to degrade allelopathy exudates and alleviate the CMO of R. glutinosa; 2) Our tissue culture model could be used to quickly screen effective microbes that could alleviate CMO in plants. (author)

Investigation of synthesis, thermal properties and curing kinetics of fluorene diamine-based benzoxazine by using two curing kinetic methods

International Nuclear Information System (INIS)

He, Xuan-yu; Wang, Jun; Ramdani, Noureddine; Liu, Wen-bin; Liu, Li-jia; Yang, Lei

2013-01-01

Graphical abstract: - Highlights: • A novel diamine-based benzoxazine monomer containing aryl ether and bulky fluorene groups (BEF-p) is synthesized. • Kinetic parameters can be calculated by Starink-LSR method and direct LSR method. • Cure reaction could be successfully described with the autocatalytic model. • The poly(BEF-p) exhibits high T g and superior thermal stability. • Aryl ether linkages had little influence on the thermal stability. - Abstract: A novel diamine-based benzoxazine monomer containing aryl ether and bulky fluorene groups (BEF-p) was prepared from the reaction of 9,9-bis-[4-(p-aminophenoxy)-phenyl]fluorene with paraformaldehyde and phenol. The chemical structure of monomer was confirmed by Fourier-transform infrared (FTIR) and 1 H and 13 C nuclear magnetic resonance spectroscopy ( 1 H and 13 C NMR). The polymerization behavior of monomer was analyzed by differential scanning calorimetry (DSC) and FTIR. The curing kinetics was studied by non-isothermal DSC, and the kinetic parameters were determined. The autocatalytic model based on two kinetic methods (Starink-LSR method and direct LSR method) showed good agreement with experimental results. The thermal and mechanical properties of poly(BEF-p) were evaluated with DSC, dynamic mechanical thermal analysis (DMTA), and thermogravimetric analysis (TGA). The results showed that the cured polymer exhibited higher glass transition temperature (T g ) and better thermal stability compared with diaminodiphenylmethane-based benzoxazine(P-ddm), and was slightly lower than those of fluorene diamine-phenol-based polybenzoxazine (poly(BF-p))

Genome Sequence of Pseudomonas sp. Strain Chol1, a Model Organism for the Degradation of Bile Salts and Other Steroid Compounds

KAUST Repository

Holert, Johannes; Alam, Intikhab; Larsen, Michael; Antunes, Andre; Bajic, Vladimir B.; Stingl, Ulrich; Philipp, Bodo

2013-01-01

Bacterial degradation of steroid compounds is of high ecological and biotechnological relevance. Pseudomonas sp. strain Chol1 is a model organism for studying the degradation of the steroid compound cholate. Its draft genome sequence is presented and reveals one gene cluster responsible for the metabolism of steroid compounds.

Genome Sequence of Pseudomonas sp. Strain Chol1, a Model Organism for the Degradation of Bile Salts and Other Steroid Compounds

KAUST Repository

Holert, Johannes

2013-01-15

Bacterial degradation of steroid compounds is of high ecological and biotechnological relevance. Pseudomonas sp. strain Chol1 is a model organism for studying the degradation of the steroid compound cholate. Its draft genome sequence is presented and reveals one gene cluster responsible for the metabolism of steroid compounds.

Emulsifying property of a viscous exopolysaccharide fromSphingomonas paucimobilis.

Science.gov (United States)

Ashtaputre, A A; Shah, A K

1995-03-01

A viscous exopolysaccharide fromSphingomonas paucimobilis-GS1, emulsified xylene, benzene, 2-methylnaphthalene, hexadecane, hexane, kerosene and paraffin oil as well as castor, coconut and olive oils when used at 1 mg/ml. It stabilized the emulsions more efficiently than commercial gums such as arabic, tragacanth, karaya and xanthan. Emulsions were stable for 6 months, from 4 to 40°C and pH 4 to 10 and in the presence of NaCl up to 50 g/l. The polysaccharide had no discernible toxicity towards mice when tested using World Health Organization guidelines.

Combination of microautoradiography and fluorescence in situ hybridization for identification of microorganisms degrading xenobiotic contaminants.

Science.gov (United States)

Yang, Yanru; Zarda, Annatina; Zeyer, Josef

2003-12-01

One of the central topics in environmental bioremediation research is to identify microorganisms that are capable of degrading the contaminants of interest. Here we report application of combined microautoradiography (MAR) and fluorescence in situ hybridization (FISH). The method has previously been used in a number of systems; however, here we demonstrate its feasibility in studying the degradation of xenobiotic compounds. With a model system (coculture of Pseudomonas putida B2 and Sphingomonas stygia incubated with [14C] o-nitrophenol), combination of MAR and FISH was shown to be able to successfully identify the microorganisms degrading o-nitrophenol. Compared with the conventional techniques, MAR-FISH allows fast and accurate identification of the microorganisms involved in environmental contaminant degradation.

Effect of Acinetobacter sp on metalaxyl degradation and metabolite profile of potato seedlings (Solanum tuberosum L. alpha variety.

Directory of Open Access Journals (Sweden)

Fabiola G Zuno-Floriano

Full Text Available One of the most serious diseases in potato cultivars is caused by the pathogen Phytophthora infestans, which affects leaves, stems and tubers. Metalaxyl is a fungicide that protects potato plants from Phytophthora infestans. In Mexico, farmers apply metalaxyl 35 times during the cycle of potato production and the last application is typically 15 days before harvest. There are no records related to the presence of metalaxyl in potato tubers in Mexico. In the present study, we evaluated the effect of Acinetobacter sp on metalaxyl degradation in potato seedlings. The effect of bacteria and metalaxyl on the growth of potato seedlings was also evaluated. A metabolite profile analysis was conducted to determine potential molecular biomarkers produced by potato seedlings in the presence of Acinetobacter sp and metalaxyl. Metalaxyl did not affect the growth of potato seedlings. However, Acinetobacter sp strongly affected the growth of inoculated seedlings, as confirmed by plant length and plant fresh weights which were lower in inoculated potato seedlings (40% and 27%, respectively compared to the controls. Acinetobacter sp also affected root formation. Inoculated potato seedlings showed a decrease in root formation compared to the controls. LC-MS/MS analysis of metalaxyl residues in potato seedlings suggests that Acinetobacter sp did not degrade metalaxyl. GC-TOF-MS platform was used in metabolic profiling studies. Statistical data analysis and metabolic pathway analysis allowed suggesting the alteration of metabolic pathways by both Acinetobacter sp infection and metalaxyl treatment. Several hundred metabolites were detected, 137 metabolites were identified and 15 metabolic markers were suggested based on statistical change significance found with PLS-DA analysis. These results are important for better understanding the interactions of putative endophytic bacteria and pesticides on plants and their possible effects on plant metabolism.

Swit_4259, an acetoacetate decarboxylase-like enzyme from Sphingomonas wittichii RW1

Energy Technology Data Exchange (ETDEWEB)

Mydy, Lisa S.; Mashhadi, Zahra; Knight, T. William; Fenske, Tyler; Hagemann, Trevor; Hoppe, Robert W.; Han, Lanlan; Miller, Todd R.; Schwabacher, Alan W.; Silvaggi, Nicholas R. (UW); (Vanderbilt)

2017-11-14

The Gram-negative bacteriumSphingomonas wittichiiRW1 is notable for its ability to metabolize a variety of aromatic hydrocarbons. Not surprisingly, theS. wittichiigenome contains a number of putative aromatic hydrocarbon-degrading gene clusters. One of these includes an enzyme of unknown function, Swit_4259, which belongs to the acetoacetate decarboxylase-like superfamily (ADCSF). Here, it is reported that Swit_4259 is a small (28.8 kDa) tetrameric ADCSF enzyme that, unlike the prototypical members of the superfamily, does not have acetoacetate decarboxylase activity. Structural characterization shows that the tertiary structure of Swit_4259 is nearly identical to that of the true decarboxylases, but there are important differences in the fine structure of the Swit_4259 active site that lead to a divergence in function. In addition, it is shown that while it is a poor substrate, Swit_4259 can catalyze the hydration of 2-oxo-hex-3-enedioate to yield 2-oxo-4-hydroxyhexanedioate. It is also demonstrated that Swit_4259 has pyruvate aldolase-dehydratase activity, a feature that is common to all of the family V ADCSF enzymes studied to date. The enzymatic activity, together with the genomic context, suggests that Swit_4259 may be a hydratase with a role in the metabolism of an as-yet-unknown hydrocarbon. These data have implications for engineering bioremediation pathways to degrade specific pollutants, as well as structure–function relationships within the ADCSF in general.

N-(Fluoren-9-ylmethoxycarbonyl-l-aspartic acid 4-tert-butyl ester

Directory of Open Access Journals (Sweden)

Kazuhiko Yamada

2009-11-01

Full Text Available The bond distances and bond angles of the title compound, C23H25NO6, are consistent with values typically found for fluoren-9-ylmethoxycarbonyl-protected amino acids. The conformations of the backbone and the side chain are slightly different from those of l-aspartic acid. The crystal structure exhibits two intermolecular hydrogen bonds, forming a two-dimensional sheet structure parallel to the ab plane.

Complete genome sequences of Geobacillus sp. Y412MC52, a xylan-degrading strain isolated from obsidian hot spring in Yellowstone National Park.

Science.gov (United States)

Brumm, Phillip; Land, Miriam L; Hauser, Loren J; Jeffries, Cynthia D; Chang, Yun-Juan; Mead, David A

2015-01-01

Geobacillus sp. Y412MC52 was isolated from Obsidian Hot Spring, Yellowstone National Park, Montana, USA under permit from the National Park Service. The genome was sequenced, assembled, and annotated by the DOE Joint Genome Institute and deposited at the NCBI in December 2011 (CP002835). Based on 16S rRNA genes and average nucleotide identity, Geobacillus sp. Y412MC52 and the related Geobacillus sp. Y412MC61 appear to be members of a new species of Geobacillus. The genome of Geobacillus sp. Y412MC52 consists of one circular chromosome of 3,628,883 bp, an average G + C content of 52 % and one circular plasmid of 45,057 bp and an average G + C content of 45 %. Y412MC52 possesses arabinan, arabinoglucuronoxylan, and aromatic acid degradation clusters for degradation of hemicellulose from biomass. Transport and utilization clusters are also present for other carbohydrates including starch, cellobiose, and α- and β-galactooligosaccharides.

Tunable properties of novel tetra-functional fluorene-based benzoxazines from mixed amines: Synthesis, characterization and curing kinetics

International Nuclear Information System (INIS)

Feng, Tiantian; Wang, Jun; Pan, Lan; Derradji, Mehdi; Ramdani, Noureddine; Liu, Wenbin; Zhou, Haoran

2016-01-01

Highlights: • Synthesis of tetra-functional fluorene-based benzoxazines with tunable properties. • Cure reaction could be successfully described with the autocatalytic model. • The benzoxazines show an excellent heat resistance with T_g of 291–307 °C. • The benzoxazines exhibit good thermal stability with T_5 over 340 °C. - Abstract: A series of tetra-functional fluorene-based benzoxazines containing both flexible linear aliphatic chain and rigid aromatic structure in their backbones were synthesized using mixed amines such as aniline and n-octylamine, 2,7-dihydroxy-9,9-bis-(4-hydroxyphenyl)fluorene (THPF) and paraformaldehyde as raw materials via Mannich reaction. The prepared benzoxazine monomers were identified by fourier transform infrared spectroscopy (FTIR), hydrogen nuclear magnetic resonance ("1H NMR). In addition, the curing behavior, curing kinetics and rheological properties of these monomers as well as the thermal and mechanical properties of their cured resins were studied using a rheometer, differential scanning calorimeter (DSC), thermogravimetric analyzer (TGA), and dynamic thermomechanical analyzer (DMA). The newly developed benzoxazines show good processibility, excellent thermal stability and high glass transition temperature (T_g) values ranging from 291 to 307 °C. By varying the proportion of n-octylamine to aniline, the properties of these resins are tuned.

Isolation and characterization of a novel hydrocarbon-degrading bacterium Achromobacter sp. HZ01 from the crude oil-contaminated seawater at the Daya Bay, southern China

International Nuclear Information System (INIS)

Deng, Mao-Cheng; Li, Jing; Liang, Fu-Rui; Yi, Meisheng; Xu, Xiao-Ming; Yuan, Jian-Ping; Peng, Juan; Wu, Chou-Fei; Wang, Jiang-Hai

2014-01-01

Graphical abstract: Morphological properties of the colonies and cells of strain HZ01. (A) Colonies of strain HZ01 on the LB solid plate; (B) Gram-negative bacterium of strain HZ01 (20 × 100); (C) Scanning electron microscopy (SEM) photograph of strain HZ01 (×15,000); and (D) Transmission electronic microscopy (TEM) photograph of strain HZ01 (×5000). - Highlights: • A novel petroleum degrading bacterium HZ01 was obtained from the crude oil-contaminated seawater. • Strain HZ01 had been identified as Achromobacter sp. • Strain HZ01 could degrade the evaporated diesel oil with the degradability of 96.6%. • Strain HZ01 could effectively degrade anthracene, phenanthrene and pyrence. • Strain HZ01 may be employed to remove hydrocarbon contaminants. - Abstract: Microorganisms play an important role in the biodegradation of petroleum contaminants, which have attracted great concern due to their persistent toxicity and difficult biodegradation. In this paper, a novel hydrocarbon-degrading bacterium HZ01 was isolated from the crude oil-contaminated seawater at the Daya Bay, South China Sea, and identified as Achromobacter sp. Under the conditions of pH 7.0, NaCl 3% (w/v), temperature 28 °C and rotary speed 150 rpm, its degradability of the total n-alkanes reached up to 96.6% after 10 days of incubation for the evaporated diesel oil. Furthermore, Achromobacter sp. HZ01 could effectively utilize polycyclic aromatic hydrocarbons (PAHs) as its sole carbon source, and could remove anthracene, phenanthrene and pyrence about 29.8%, 50.6% and 38.4% respectively after 30 days of incubation. Therefore, Achromobacter sp. HZ01 may employed as an excellent degrader to develop one cost-effective and eco-friendly method for the bioremediation of marine environments polluted by crude oil

Stenotrophomonas sp. RZS 7, a novel PHB degrader isolated from plastic contaminated soil in Shahada, Maharashtra, Western India.

Science.gov (United States)

Wani, S J; Shaikh, S S; Tabassum, B; Thakur, R; Gulati, A; Sayyed, R Z

2016-12-01

This paper reports an isolation and identification of novel poly-β-hydroxybutyrate (PHB) degrading bacterium Stenotrophomonas sp. RZS 7 and studies on its extracellular PHB degrading depolymerase enzyme. The bacterium isolated from soil samples of plastic contaminated sites of municipal area in Shahada, Maharashtra, Western India. It was identified as Stenotrophomonas sp. RZS 7 based on polyphasic approach. The bacterium grew well in minimal salt medium (MSM) and produced a zone (4.2 mm) of PHB hydrolysis on MSM containing PHB as the only source of nutrient. An optimum yield of enzyme was obtained on the fifth day of incubation at 37 °C and at pH 6.0. Further increase in enzyme production was recorded with Ca 2+ ions, while other metal ions like Fe 2+ (1 mM) and chemical viz. mercaptoethanol severally affected the production of enzyme.

Soil bacteria for remediation of polluted soils

Energy Technology Data Exchange (ETDEWEB)

Springael, D; Bastiaens, L; Carpels, M; Mergaey, M; Diels, L

1996-09-18

Soil bacteria, specifically adapted to contaminated soils, may be used for the remediation of polluted soils. The Flemish research institute VITO has established a collection of bacteria, which were isolated from contaminated areas. This collection includes microbacteria degrading mineral oils (Pseudomonas sp., Acinetobacter sp. and others), microbacteria degrading polycyclic aromatic hydrocarbons (genera Sphingomonas and Mycobacterium), microbacteria degrading polychlorobiphenyls (genus Ralstonia and strains related to beta-Proteobacteria), and metal resistant bacteria with plasmid borne resistances to Cd, Zn, Ni, Co, Cu, Hg, and Cr. Bench-scale reactors were developed to investigate the industrial feasibility of bioremediation. Batch Stirred Tank Reactors were used to evaluate the efficiency of oil degraders. Soils, contaminated with non-ferrous metals, were treated using a Bacterial Metal Slurry Reactor. It was found that the reduction of the Cd concentration may vary strongly from sample to sample: reduction factors vary from 95 to 50%. Is was shown that Cd contained in metallic sinter and biologically unavailable Cd could not be removed.

Interactions of rice (Oryza sativa L.) and PAH-degrading bacteria (Acinetobacter sp.) on enhanced dissipation of spiked phenanthrene and pyrene in waterlogged soil.

Science.gov (United States)

Gao, Y; Yu, X Z; Wu, S C; Cheung, K C; Tam, N F Y; Qian, P Y; Wong, M H

2006-12-15

The effects of cultivation of rice (Oryza sativa L.) and PAH-degrading bacteria (Acinetobacter sp.) separately, and in combination, on the dissipation of spiked phenanthrene and pyrene (0, 50+50, 100+100, 200+200 mg kg(-1)) in waterlogged soil were studied using pot trials. The population of introduced PAH-degrading bacteria remained at 10(5) CFU g(-1) dry soil after 20 days of treatment with Acinetobacter sp. only, but increased to 10(6) when planted with rice simultaneously. Shoot and root biomass of rice when grown alone was adversely affected by spiked PAHs, but significantly increased by 2-55% and 8-409%, respectively, when inoculated with Acinetobacter sp.. Phenanthrene and pyrene concentrations in roots ranged from 1-27 and 20-98 mg kg(-1), respectively, while their concentrations in shoots were generally lower than 0.2 mg kg(-1). The dissipation of phenanthrene was mainly due to abiotic loss as 70-78% phenanthrene was lost from the control soil at the end of 80 days, while removal of 86-87% phenanthrene had been achieved after 40 days in the treatment co-cultivated with Acinetobacter sp. and rice. Compared with the control where only 6-15% of pyrene was removed from soil, a much higher dissipation of pyrene (43-62%) was attained for the treatments co-cultivated with Acinetobacter sp. and rice at the end of 80 days. The results demonstrated that co-cultivation of rice and PAH-degrading bacteria may have a great potential to accelerate the bioremediation process of PAH-contaminated soil under waterlogged conditions.

Plastic degradation by thermophilic Bacillus sp. BCBT21 isolated from composting agricultural residual in Vietnam

Science.gov (United States)

Dang, Thi Cam Ha; Thang Nguyen, Dang; Thai, Hoang; Chinh Nguyen, Thuy; Thu Hien Tran, Thi; Le, Viet Hung; Huynh Nguyen, Van; Bach Tran, Xuan; Phuong Thao Pham, Thi; Giang Nguyen, Truong; Nguyen, Quang Trung

2018-03-01

Three different kinds of plastic bags HL, VHL, and VN1 with different chemical nature were degraded by a novel thermophilic bacterial strain isolated from composting agricultural residual in Vietnam in shaking liquid medium at 55 °C after 30 d. The new strain was classified in the Bacillus genus by morphological property and sequence of partial 16Sr RNA coding gene and named as Bacillus sp. BCBT21. This strain could produce extracellular hydrolase enzymes including lipase, CMCase, xylanase, chitinase, and protease with different level of activity in the same media. After a 30-d treatment at 55 °C with Bacillus sp. BCBT21, all characteristics including properties and morphology of treated plastic bags had been significantly changed. The weight loss, structure and surface morphology of these bags as well as the change in the average molecular weight of VHL bag were detected. Especially, the average molecular weight of VHL bag was significantly reduced from 205 000 to 116 760. New metabolites from the treated bags indicated biodegradation occurring with the different pathways. This finding suggests that there is high potential to develop an effective integrated method for plastic bags degradation by a combination of extracellular enzymes from bacteria and fungi existing in the composting process.

Isolation and characterization of Halomonas sp. strain C2SS100, a hydrocarbon-degrading bacterium under hypersaline conditions.

Science.gov (United States)

Mnif, S; Chamkha, M; Sayadi, S

2009-09-01

To isolate and characterize an efficient hydrocarbon-degrading bacterium under hypersaline conditions, from a Tunisian off-shore oil field. Production water collected from 'Sercina' petroleum reservoir, located near the Kerkennah island, Tunisia, was used for the screening of halotolerant or halophilic bacteria able to degrade crude oil. Bacterial strain C2SS100 was isolated after enrichment on crude oil, in the presence of 100 g l(-1) NaCl and at 37 degrees C. This strain was aerobic, Gram-negative, rod-shaped, motile, oxidase + and catalase +. Phenotypic characters and phylogenetic analysis based on the 16S rRNA gene of the isolate C2SS100 showed that it was related to members of the Halomonas genus. The degradation of several compounds present in crude oil was confirmed by GC-MS analysis. The use of refined petroleum products such as diesel fuel and lubricating oil as sole carbon source, under the same conditions of temperature and salinity, showed that significant amounts of these heterogenic compounds could be degraded. Strain C2SS100 was able to degrade hexadecane (C16). During growth on hexadecane, cells surface hydrophobicity and emulsifying activity increased indicating the production of biosurfactant by strain C2SS100. A halotolerant bacterial strain Halomonas sp. C2SS100 was isolated from production water of an oil field, after enrichment on crude oil. This strain is able to degrade hydrocarbons efficiently. The mode of hydrocarbon uptake is realized by the production of a biosurfactant which enhances the solubility of hydrocarbons and renders them more accessible for biodegradation. The biodegradation potential of the Halomonas sp. strain C2SS100 gives it an advantage for possibly application on bioremediation of water, hydrocarbon-contaminated sites under high-salinity level.

Apparent Contradiction: Psychrotolerant Bacteria from Hydrocarbon-Contaminated Arctic Tundra Soils That Degrade Diterpenoids Synthesized by Trees

Science.gov (United States)

Yu, Zhongtang; Stewart, Gordon R.; Mohn, William W.

2000-01-01

Resin acids are tricyclic terpenoids occurring naturally in trees. We investigated the occurrence of resin acid-degrading bacteria on the Arctic tundra near the northern coast of Ellesmere Island (82°N, 62°W). According to most-probable-number assays, resin acid degraders were abundant (103 to 104 propagules/g of soil) in hydrocarbon-contaminated soils, but they were undetectable (soil) in pristine soils from the nearby tundra. Plate counts indicated that the contaminated and the pristine soils had similar populations of heterotrophs (106 to 107 propagules/g of soil). Eleven resin acid-degrading bacteria belonging to four phylogenetically distinct groups were enriched and isolated from the contaminated soils, and representative isolates of each group were further characterized. Strains DhA-91, IpA-92, and IpA-93 are members of the genus Pseudomonas. Strain DhA-95 is a member of the genus Sphingomonas. All four strains are psychrotolerant, with growth temperature ranges of 4°C to 30°C (DhA-91 and DhA-95) or 4°C to 22°C (IpA-92 and IpA-93) and with optimum temperatures of 15 to 22°C. Strains DhA-91 and DhA-95 grew on the abietanes, dehydroabietic and abietic acids, but not on the pimaranes, isopimaric and pimaric acids. Strains IpA-92 and IpA-93 grew on the pimaranes but not the abietanes. All four strains grew on either aliphatic or aromatic hydrocarbons, which is unusual for described resin acid degraders. Eleven mesophilic resin acid degraders did not use hydrocarbons, with the exception of two Mycobacterium sp. strains that used aliphatic hydrocarbons. We conclude that hydrocarbon contamination in Arctic tundra soil indirectly selected for resin acid degraders, selecting for hydrocarbon degraders that coincidentally use resin acids. Psychrotolerant resin acid degraders are likely important in the global carbon cycle and may have applications in biotreatment of pulp and paper mill effluents. PMID:11097882

Comparison of n-eicosane and phenanthrene removal by pure and mixed cultures of two marine bacteria

International Nuclear Information System (INIS)

Syakti, A.D.; Acquaviva, M.; Gilewicz, M.; Doumenq, P.; Bertrand, J.C.

2004-01-01

The biotransformation activities of two hydrocarbonoclastic marine bacteria, Corynebacterium sp. and Sphingomonas sp. 2MPII, on n-eicosane and phenanthrene were investigated. During a 56-day experiment, in pure and mixed cultures, Corynebacterium sp. and Sphingomonas sp. 2MPII removed about 70% of the initial n-eicosane and phenanthrene concentrations (1 and 0.4 g L -1 , respectively). In pure cultures, culturable cell abundances increased over time, from 0.8 to 8.6x10 -11 CFU L -1 (Corynebacterium sp.) and from 2.1 to 16x10 -11 CFU L -1 (Sphingomonas sp. 2MPII ) but remained barely constant in mixed cultures. We defined a biotransformation index based on the number of culturable cells rather than the culture protein content, with the biotransformation cell yield (BCY) expressed in grams hydrocarbon CFU -1 per day to better characterize hydrocarbon removal in pure and mixed cultures. The BCY was markedly higher in mixed than in pure cultures, increasing by a factor of 2-10.7 and 2.3-4.7 for n-eicosane and phenanthrene removal, respectively

A new boronic acid fluorescent sensor based on fluorene for monosaccharides at physiological pH.

Science.gov (United States)

Hosseinzadeh, Rahman; Mohadjerani, Maryam; Pooryousef, Mona; Eslami, Abbas; Emami, Saeed

2015-06-05

Fluorescent boronic acids are very useful fluorescent sensor for detection of biologically important saccharides. Herein we synthesized a new fluorene-based fluorescent boronic acid that shows significant fluorescence changes upon addition of saccharides at physiological pH. Upon addition of fructose, sorbitol, glucose, galactose, ribose, and maltose at different concentration to the solution of 7-(dimethylamino)-9,9-dimethyl-9H-fluoren-2-yl-2-boronic acid (7-DMAFBA, 1), significant decreases in fluorescent intensity were observed. It was found that this boronic acid has high affinity (K(a)=3582.88 M(-1)) and selectivity for fructose over glucose at pH=7.4. The sensor 1 showed a linear response toward d-fructose in the concentrations ranging from 2.5×10(-5) to 4×10(-4) mol L(-1) with the detection limit of 1.3×10(-5) mol L(-1). Copyright © 2015 Elsevier B.V. All rights reserved.

Polycyclic aromatic hydrocarbons (PAHs) biodegradation potential and diversity of microbial consortia enriched from tsunami sediments in Miyagi, Japan

Energy Technology Data Exchange (ETDEWEB)

Bacosa, Hernando Pactao, E-mail: hernando.bacosa@utexas.edu [Graduate School of Environmental Studies, Tohoku University, Aoba 6-6-20, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Marine Science Institute, The University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373 (United States); Inoue, Chihiro [Graduate School of Environmental Studies, Tohoku University, Aoba 6-6-20, Aramaki, Aoba-ku, Sendai 980-8579 (Japan)

2015-02-11

Highlights: • Most bacterial consortia from tsunami sediment degraded PAH mixture and pyrene. • The consortia were dominated by known and unknown PAHs-degrading bacteria. • Dokdonella clone is a potential new species and PAH degrader from tsunami sediment. • PAH-RHDα is better than nidA gene for estimating pyrene-degraders in the consortia. • First report on the PAH degradation and PAH-degrading bacteria from tsunami sediment. - Abstract: The Great East Japan Earthquake caused tsunamis and resulted in widespread damage to human life and infrastructure. The disaster also resulted in contamination of the environment by chemicals such as polycyclic aromatic hydrocarbons (PAHs). This study was conducted to investigate the degradation potential and describe the PAH-degrading microbial communities from tsunami sediments in Miyagi, Japan. PAH-degrading bacteria were cultured by enrichment using PAH mixture or pyrene alone as carbon and energy sources. Among the ten consortia tested for PAH mixture, seven completely degraded fluorene and more than 95% of phenanthrene in 10 days, while only four consortia partially degraded pyrene. Six consortia partially degraded pyrene as a single substrate. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that each sample was dominated by unique microbial populations, regardless of sampling location. The consortia were dominated by known PAHs degraders including Sphingomonas, Pseudomonas, and Sphingobium; and previously unknown degraders such as Dokdonella and Luteimonas. A potentially novel and PAH-degrading Dokdonella was detected for the first time. PAH-ring hydroxylating dioxygenase (PAH-RHDα) gene was shown to be more effective than nidA in estimating pyrene-degrading bacteria in the enriched consortia. The consortia obtained in this study are potential candidates for remediation of PAHs contaminated soils.

Polycyclic aromatic hydrocarbons (PAHs) biodegradation potential and diversity of microbial consortia enriched from tsunami sediments in Miyagi, Japan

International Nuclear Information System (INIS)

Bacosa, Hernando Pactao; Inoue, Chihiro

2015-01-01

Highlights: • Most bacterial consortia from tsunami sediment degraded PAH mixture and pyrene. • The consortia were dominated by known and unknown PAHs-degrading bacteria. • Dokdonella clone is a potential new species and PAH degrader from tsunami sediment. • PAH-RHDα is better than nidA gene for estimating pyrene-degraders in the consortia. • First report on the PAH degradation and PAH-degrading bacteria from tsunami sediment. - Abstract: The Great East Japan Earthquake caused tsunamis and resulted in widespread damage to human life and infrastructure. The disaster also resulted in contamination of the environment by chemicals such as polycyclic aromatic hydrocarbons (PAHs). This study was conducted to investigate the degradation potential and describe the PAH-degrading microbial communities from tsunami sediments in Miyagi, Japan. PAH-degrading bacteria were cultured by enrichment using PAH mixture or pyrene alone as carbon and energy sources. Among the ten consortia tested for PAH mixture, seven completely degraded fluorene and more than 95% of phenanthrene in 10 days, while only four consortia partially degraded pyrene. Six consortia partially degraded pyrene as a single substrate. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) revealed that each sample was dominated by unique microbial populations, regardless of sampling location. The consortia were dominated by known PAHs degraders including Sphingomonas, Pseudomonas, and Sphingobium; and previously unknown degraders such as Dokdonella and Luteimonas. A potentially novel and PAH-degrading Dokdonella was detected for the first time. PAH-ring hydroxylating dioxygenase (PAH-RHDα) gene was shown to be more effective than nidA in estimating pyrene-degrading bacteria in the enriched consortia. The consortia obtained in this study are potential candidates for remediation of PAHs contaminated soils

Syntrophomonas zehnderi sp. nov., an anaerobe that degrades long-chain fatty acids in co-culture with Methanobacterium formicicum.

Science.gov (United States)

Sousa, Diana Z; Smidt, Hauke; Alves, M Madalena; Stams, Alfons J M

2007-03-01

An anaerobic, mesophilic, syntrophic fatty-acid-oxidizing bacterium, designated strain OL-4(T), was isolated as a co-culture with Methanobacterium formicicum DSM 1535(NT) from an anaerobic expanded granular sludge bed reactor used to treat an oleate-based effluent. Strain OL-4(T) degraded oleate, a mono-unsaturated fatty acid, and straight-chain fatty acids C(4 : 0)-C(18 : 0) in syntrophic association with Methanobacterium formicicum DSM 1535(NT). Even-numbered fatty acids were degraded to acetate and methane whereas odd-numbered fatty acids were degraded to acetate, propionate and methane. Branched-chain fatty acids were not degraded. The bacterium could not grow axenically with any other substrate tested and therefore is considered to be obligately syntrophic. Fumarate, sulfate, thiosulfate, sulfur and nitrate could not serve as electron acceptors for strain OL-4(T) to degrade oleate or butyrate. Cells of strain OL-4(T) were curved rods, formed spores and showed a variable response to Gram staining. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain OL-4(T) was most closely related to the fatty-acid-oxidizing, syntrophic bacterium Syntrophomonas sp. TB-6 (95 % similarity), Syntrophomonas wolfei subsp. wolfei DSM 2245(T) (94 % similarity) and Syntrophomonas erecta DSM 16215(T) (93 % similarity). In addition to this moderate similarity, phenotypic and physiological characteristics, such as obligate syntrophy, spore formation and utilization of a broader substrate range, differentiated strain OL-4(T) from these Syntrophomonas species. Therefore strain OL-4(T) represents a novel species, for which the name Syntrophomonas zehnderi sp. nov. is proposed. The type strain is OL-4(T) (=DSM 17840(T)=JCM 13948(T)).

Cloning and characterization of genes involved in nostoxanthin biosynthesis of Sphingomonas elodea ATCC 31461.

Directory of Open Access Journals (Sweden)

Liang Zhu

Full Text Available Most Sphingomonas species synthesize the yellow carotenoid nostoxanthin. However, the carotenoid biosynthetic pathway of these species remains unclear. In this study, we cloned and characterized a carotenoid biosynthesis gene cluster containing four carotenogenic genes (crtG, crtY, crtI and crtB and a β-carotene hydroxylase gene (crtZ located outside the cluster, from the gellan-gum producing bacterium Sphingomonas elodea ATCC 31461. Each of these genes was inactivated, and the biochemical function of each gene was confirmed based on chromatographic and spectroscopic analysis of the intermediates accumulated in the knockout mutants. Moreover, the crtG gene encoding the 2,2'-β-hydroxylase and the crtZ gene encoding the β-carotene hydroxylase, both responsible for hydroxylation of β-carotene, were confirmed by complementation studies using Escherichia coli producing different carotenoids. Expression of crtG in zeaxanthin and β-carotene accumulating E. coli cells resulted in the formation of nostoxanthin and 2,2'-dihydroxy-β-carotene, respectively. Based on these results, a biochemical pathway for synthesis of nostoxanthin in S. elodea ATCC 31461 is proposed.

Cloning and characterization of genes involved in nostoxanthin biosynthesis of Sphingomonas elodea ATCC 31461.

Science.gov (United States)

Zhu, Liang; Wu, Xuechang; Li, Ou; Qian, Chaodong; Gao, Haichun

2012-01-01

Most Sphingomonas species synthesize the yellow carotenoid nostoxanthin. However, the carotenoid biosynthetic pathway of these species remains unclear. In this study, we cloned and characterized a carotenoid biosynthesis gene cluster containing four carotenogenic genes (crtG, crtY, crtI and crtB) and a β-carotene hydroxylase gene (crtZ) located outside the cluster, from the gellan-gum producing bacterium Sphingomonas elodea ATCC 31461. Each of these genes was inactivated, and the biochemical function of each gene was confirmed based on chromatographic and spectroscopic analysis of the intermediates accumulated in the knockout mutants. Moreover, the crtG gene encoding the 2,2'-β-hydroxylase and the crtZ gene encoding the β-carotene hydroxylase, both responsible for hydroxylation of β-carotene, were confirmed by complementation studies using Escherichia coli producing different carotenoids. Expression of crtG in zeaxanthin and β-carotene accumulating E. coli cells resulted in the formation of nostoxanthin and 2,2'-dihydroxy-β-carotene, respectively. Based on these results, a biochemical pathway for synthesis of nostoxanthin in S. elodea ATCC 31461 is proposed.

Luminescent Fluorene-Based Bis-Pyrazolyl Aniline Ligand for Aluminum Detection.

Science.gov (United States)

Frazer, Andrew; Morales, Alma R; Woodward, Adam W; Tongwa, Paul; Timofeeva, Tatiana; Belfield, Kevin D

2013-09-29

The design, synthesis, and photophysical properties of a new fluorene-based fluorescent chemosensor, 4-((E)-2-(2-(benzo[d]thiazol-2-yl)-9,9-diethyl-9H-fluoren-7-yl)vinyl)-N,N-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)benzenamine (AXF-Al), is described for the detection of Al 3+ . AXF-Al exhibited absorption at 382 nm and strong fluorescence emission at 542 nm (fluorescence quantum yield, Φ F , of 0.80). The capture of Al 3+ by the pyrazolyl aniline receptor resulted in nominal change in the linear absorption (372 nm) but a large hypsochromic shift of 161 nm in the fluorescence spectrum (542 to 433 nm, Φ F  = 0.88), from which Al 3+ was detected both ratiometrically and colorimetrically. The addition of other metal ions, namely Mg 2+ , Ca 2+ , Mn 2+ , Fe 2+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Cd 2+ , Hg 2+ and Pb 2+ , produced only minimal changes in the optical properties of this probe. The emission band of this probe was also accessed by two-photon excitation in the near-IR, as two-photon absorption (2PA) is important for potential applications in two-photon fluorescence microscopy (2PFM) imaging. The 2PA cross section of the free fluorenyl ligand AXF-Al was 220 GM at 810 nm and 235 GM at 810 nm for the Al-ligand complex, practically useful properties for 2PFM.

Characteristics of raw starch degrading alpha-amylase from Bacillus aquimaris MKSC 6.2 associated with soft coral Sinularia sp.

NARCIS (Netherlands)

Puspasari, Fernita; Nurachman, Zeily; Noer, Achmad Saefuddin; Radjasa, Ocky Karna; van der Maarel, Marc J. E. C.; Natalia, Dessy

Partially purified alpha-amylase from Bacillus aquimaris MKSC 6.2, a bacterium isolated from a soft coral Sinularia sp., Merak Kecil Island, West Java, Indonesia, showed an ability to degrade raw corn, rice, sago, cassava, and potato starches with adsorption percentage in the range of 65-93%. Corn

Bacterial Degradation of Aromatic Compounds

Directory of Open Access Journals (Sweden)

Qing X. Li

2009-01-01

Full Text Available Aromatic compounds are among the most prevalent and persistent pollutants in the environment. Petroleum-contaminated soil and sediment commonly contain a mixture of polycyclic aromatic hydrocarbons (PAHs and heterocyclic aromatics. Aromatics derived from industrial activities often have functional groups such as alkyls, halogens and nitro groups. Biodegradation is a major mechanism of removal of organic pollutants from a contaminated site. This review focuses on bacterial degradation pathways of selected aromatic compounds. Catabolic pathways of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene are described in detail. Bacterial catabolism of the heterocycles dibenzofuran, carbazole, dibenzothiophene, and dibenzodioxin is discussed. Bacterial catabolism of alkylated PAHs is summarized, followed by a brief discussion of proteomics and metabolomics as powerful tools for elucidation of biodegradation mechanisms.

Diaryl fluorene-Based Shape-Persistent Organic Nano molecular Frameworks via Iterative Friedel-Crafts Protocol toward Multicomponent Organic Semiconductors

International Nuclear Information System (INIS)

Zhang, G.W.; Wang, L.; Xie, L.H.; Hou, X.Y.; Liu, Z.D.; Huang, W.; Huang, W.

2013-01-01

We describe bottom-up fluorenol approach to create soluble covalent organic nano molecular architectures (ONAs) as potential multicomponent organic semiconductors (MOSs). BPyFBFFA as a typical model of ONAs and MOSs exhibits a persistent chair-shaped geometric structure that consists of hole-transporting tri phenylamine (TPA), high-efficiency ter fluorene, and high-mobility pyrenes. BPyFBFFA was synthesized via the intermediates PyFA and BPyFA with iterative Friedel-Crafts reactions and Suzuki cross-coupling reactions. BPyFBFFA behaves as an efficient blue light-emitter without the low-energy green emission band. Complex diaryl fluorenes (CDAFs) are promising candidates for nano scale covalent organic frameworks and MOSs. Friedel-Crafts protocols offer versatile toolboxes for molecular architects to frame chemistry and materials, nano science, and molecular nano technology as well as molecular manufactures

Degradation of ethyl mercaptan and its major intermediate diethyl disulfide by Pseudomonas sp. strain WL2.

Science.gov (United States)

Wang, Xiangqian; Wu, Chao; Liu, Nan; Li, Sujing; Li, Wei; Chen, Jianmeng; Chen, Dongzhi

2015-04-01

A Pseudomonas sp. strain WL2 that is able to efficiently metabolize ethyl mercaptan (EM) into diethyl disulfide (DEDS) through enzymatic oxidation was isolated from the activated sludge of a pharmaceutical wastewater plant. One hundred percent removal of 113.5 mg L(-1) EM and 110.3 mg L(-1) DEDS were obtained within 14 and 32 h, respectively. A putative EM degradation pathway that involved the catabolism via DEDS was proposed, which indicated DEDS were further mineralized into carbon dioxide (CO2), bacterial cells, and sulfate (SO4 (2-)) through the transformation of element sulfur and ethyl aldehyde. Degradation kinetics for EM and DEDS with different initial concentrations by strain WL2 were evaluated using Haldane-Andrews model with maximum specific degradation rates of 3.13 and 1.33 g g(-1) h(-1), respectively, and maximum degradation rate constants of 0.522 and 0.175 h(-1) using pseudo-first-order kinetic model were obtained. Results obtained that aerobic degradation of EM by strain WL2 was more efficient than those from previous studies. Substrate range studies of strain WL2 demonstrated its ability to degrade several mercaptans, disulfides, aldehydes, and methanol. All the results obtained highlight the potential of strain WL2 for the use in the biodegradation of volatile organic sulfur compounds (VOSCs).

'Rare biosphere' bacteria as key phenanthrene degraders in coastal seawaters.

Science.gov (United States)

Sauret, Caroline; Séverin, Tatiana; Vétion, Gilles; Guigue, Catherine; Goutx, Madeleine; Pujo-Pay, Mireille; Conan, Pascal; Fagervold, Sonja K; Ghiglione, Jean-François

2014-11-01

By coupling DNA-SIP and pyrosequencing approaches, we identified Cycloclasticus sp. as a keystone degrader of polycyclic aromatic hydrocarbons (PAH) despite being a member of the 'rare biosphere' in NW Mediterranean seawaters. We discovered novel PAH-degrading bacteria (Oceanibaculum sp., Sneathiella sp.) and we identified other groups already known to possess this function (Alteromonas sp., Paracoccus sp.). Together with Cycloclasticus sp., these groups contributed to potential in situ phenanthrene degradation at a rate >0.5 mg l(-1) day(-1), sufficient to account for a considerable part of PAH degradation. Further, we characterized the PAH-tolerant bacterial communities, which were much more diverse in the polluted site by comparison to unpolluted marine references. PAH-tolerant bacteria were also members of the rare biosphere, such as Glaciecola sp. Collectively, these data show the complex interactions between PAH-degraders and PAH-tolerant bacteria and provide new insights for the understanding of the functional ecology of marine bacteria in polluted waters. Copyright © 2014 Elsevier Ltd. All rights reserved.

AcEST: BP919070 [AcEST

Lifescience Database Archive (English)

Full Text Available -associated... 32 2.9 sp|Q7X2N3|SYV_SPHEL Valyl-tRNA synthetase OS=Sphingomonas elodea...nthetase OS=Sphingomonas elodea GN=valS PE=3 SV=1 Length = 811 Score = 30.4 bits (67), Expect = 6.5 Identiti

Eficiencia de pseudomonas sp, rhodopseudomonas sp, micrococcus sp y bacillus sp empleados como cultivos individuales y en consorcio, en la degradación de petróleo diesel ii

OpenAIRE

Otiniano García, Nélida Milly Esther

2010-01-01

In order to evaluate the efficiency of Pseudomonas sp, Rhodopseudomonas sp, Micrococcus sp, Bacillus sp, and the consortium formed by these four microorganisms in the diesel II petroleum degradation, it was worked in 5 bioreactors of aerated and shaken tank of 1.5 litters of capacity, with speed agitation of 120 rpm, and air flow of 0.5 vvm; in which were placed; 940 mL of Minimum Broth of Davies pH 7.0; 50 mL of diesel II petroleum as source of carbon and 10 mL of a suspension of approx...

Aerobic degradation of N-methyl-4-nitroaniline (MNA by Pseudomonas sp. strain FK357 isolated from soil.

Directory of Open Access Journals (Sweden)

Fazlurrahman Khan

Full Text Available N-Methyl-4-nitroaniline (MNA is used as an additive to lower the melting temperature of energetic materials in the synthesis of insensitive explosives. Although the biotransformation of MNA under anaerobic condition has been reported, its aerobic microbial degradation has not been documented yet. A soil microcosms study showed the efficient aerobic degradation of MNA by the inhabitant soil microorganisms. An aerobic bacterium, Pseudomonas sp. strain FK357, able to utilize MNA as the sole carbon, nitrogen, and energy source, was isolated from soil microcosms. HPLC and GC-MS analysis of the samples obtained from growth and resting cell studies showed the formation of 4-nitroaniline (4-NA, 4-aminophenol (4-AP, and 1, 2, 4-benzenetriol (BT as major metabolic intermediates in the MNA degradation pathway. Enzymatic assay carried out on cell-free lysates of MNA grown cells confirmed N-demethylation reaction is the first step of MNA degradation with the formation of 4-NA and formaldehyde products. Flavin-dependent transformation of 4-NA to 4-AP in cell extracts demonstrated that the second step of MNA degradation is a monooxygenation. Furthermore, conversion of 4-AP to BT by MNA grown cells indicates the involvement of oxidative deamination (release of NH2 substituent reaction in third step of MNA degradation. Subsequent degradation of BT occurs by the action of benzenetriol 1, 2-dioxygenase as reported for the degradation of 4-nitrophenol. This is the first report on aerobic degradation of MNA by a single bacterium along with elucidation of metabolic pathway.

Novel degradation pathway and kinetic analysis for buprofezin removal by newly isolated Bacillus sp.

Science.gov (United States)

Wang, Guangli; Xu, Dayong; Xiong, Minghua; Zhang, Hui; Li, Feng; Liu, Yuan

2016-09-15

Given the intensive and widespread application of the pesticide, buprofezin, its environmental residues potentially pose a problem; yet little is known about buprofezin's kinetic and metabolic behaviors. In this study, a novel gram-positive strain, designated BF-5, isolated from aerobic activated sludge, was found to be capable of metabolizing buprofezin as its sole energy, carbon, and nitrogen source. Based on its physiological and biochemical characteristics, other aspects of its phenotype, and a phylogenetic analysis, strain BF-5 was identified as Bacillus sp. This study investigated the effect of culture conditions on bacterial growth and substrate degradation, such as pH, temperature, initial concentration, different nitrogen source, and additional nitrogen sources as co-substrates. The degradation rate parameters, qmax, Ks, Ki and Sm were determined to be 0.6918 h(-1), 105.4 mg L(-1), 210.5 mg L(-1), and 148.95 mg L(-1) respectively. The capture of unpublished potential metabolites by gas chromatography-mass spectrometry (GC-MS) analysis has led to the proposal of a novel degradation pathway. Taken together, our results clarify buprofezin's biodegradation pathway(s) and highlight the promising potential of strain BF-5 in bioremediation of buprofezin-contaminated environments. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hydrocarbon degradation potential in reference soils and soils contaminated with jet fuel

International Nuclear Information System (INIS)

Lee, R.F.; Hoeppel, R.

1991-01-01

Petroleum degradation in surface and subsurface soils is affected by such factors as moisture content, pH, soil type, soil organics, temperature, and oxygen concentrations. In this paper, the authors determine the degradation rates of 14 C-labeled hydrocarbons added to soils collected from a contaminated surface site, contaminated subsurface sites, and a clean reference site. The radiolabeled hydrocarbons used include benzene, toluene, naphthalene, 1-methynaphthalene, phenanthrene, fluorene, anthracene, chrysene, and hexadecane. Microbial degradation rates were based on determination of mineralization rates (production of 14 CO 2 ) of hydrocarbons that were added to soil samples. Since water was added and oxygen was not limiting, the hydrocarbon rates determined are likely to be higher than those occurring in situ. Using radiolabeled hydrocarbons, information can be provided on differences in the degradation rates of various petroleum compounds in different types of soils at a site, on possible production of petroleum metabolites in the soil, and on the importance of anaerobic petroleum degradation and the effects of nutrient, water, and surfactant addition on biodegradation rates

CF3DODA-Me induces apoptosis, degrades Sp1, and blocks the transformation phase of the blebbishield emergency program.

Science.gov (United States)

Taoka, Rikiya; Jinesh, Goodwin G; Xue, Wenrui; Safe, Stephen; Kamat, Ashish M

2017-05-01

Cancer stem cells are capable of undergoing cellular transformation after commencement of apoptosis through the blebbishield emergency program in a VEGF-VEGFR2-dependent manner. Development of therapeutics targeting the blebbishield emergency program would thus be important in cancer therapy. Specificity protein 1 (Sp1) orchestrates the transcription of both VEGF and VEGFR2; hence, Sp1 could act as a therapeutic target. Here, we demonstrate that CF 3 DODA-Me induced apoptosis, degraded Sp1, inhibited the expression of multiple drivers of the blebbishield emergency program such as VEGFR2, p70S6K, and N-Myc through activation of caspase-3, inhibited reactive oxygen species; and inhibited K-Ras activation to abolish transformation from blebbishields as well as transformation in soft agar. These findings confirm CF 3 DODA-Me as a potential therapeutic candidate that can induce apoptosis and block transformation from blebbishields.

Otomastoiditis caused by Sphingomonas paucimobilis: case report and literature review.

Science.gov (United States)

Benevides, Gabriel Nuncio; Hein, Noely; Lo, Denise Swei; Ferronato, Angela Esposito; Ragazzi, Selma Lopes Betta; Yoshioka, Cristina Ryoka Miyao; Hirose, Maki; Cardoso, Debora Morais; Regina Dos Santos, Silvia; Gilio, Alfredo Elias

2014-01-01

Sphingomonas paucimobilis is an aerobic Gram-negative bacillus that, although rare in humans, most commonly infects immunocompromised and hospitalized patients. Among the 59 pediatric cases of S. paucimobilis infection reported in the literature, the most common diagnosis involves isolated bacteremia. These cases are related to sporadic or epidemic infections. Death related to this infection occurred in only one case. The authors report a case of an 11-year-old boy with the diagnosis of Sphingomonas paucimobilis otomastoiditis and a thorough review of the literature on this infection in pediatrics. The patient presented a 20-day history of fever, otalgia, otorrhea, and progressive retroauricular swelling with protrusion of the left ear; despite 15 days of amoxicillin regimen. His past medical history included chronic bilateral otitis media, but no cause of immunosuppression was found. A brain computed tomography scan showed left otomastoiditis associated with a large circumscribed fluid collection with deep involvement of the soft tissues of the temporal region, including the subperiosteal space. Blood tests showed neutrophilia and elevated C-reactive protein. Surgical manipulation of the cited collection drained a large amount of a fetid purulent secretion. Ceftazidime and clindamycin were empirically initiated. The outcome was favorable, with fever defervescence and resolution of the scalp deformation. Culture of the drained secretion was positive for S. paucimobilis . Ciprofloxacin was scheduled for a further 10 days after discharge. The follow-up showed complete recovery. As far as we know, this is the first case of S. paucimobilis otomastoiditis, complicated with subperiosteal abscess in an immunocompetent child. The authors call attention to the increasing number of reports on S. paucimobilis infection over the years, and therefore to the importance of this pathogen, which was previously underestimated.

Otomastoiditis caused by Sphingomonas paucimobilis: case report and literature review

Directory of Open Access Journals (Sweden)

Gabriel Nuncio Benevides

2014-09-01

Full Text Available Sphingomonas paucimobilis is an aerobic Gram-negative bacillus that, although rare in humans, most commonly infects immunocompromised and hospitalized patients. Among the 59 pediatric cases of S. paucimobilis infection reported in the literature, the most common diagnosis involves isolated bacteremia. These cases are related to sporadic or epidemic infections. Death related to this infection occurred in only one case. The authors report a case of an 11-year-old boy with the diagnosis of Sphingomonas paucimobilis otomastoiditis and a thorough review of the literature on this infection in pediatrics. The patient presented a 20-day history of fever, otalgia, otorrhea, and progressive retroauricular swelling with protrusion of the left ear; despite 15 days of amoxicillin regimen. His past medical history included chronic bilateral otitis media, but no cause of immunosuppression was found. A brain computed tomography scan showed left otomastoiditisassociated with a large circumscribed fluid collection with deep involvement of the soft tissues of the temporal region, including the subperiosteal space. Blood tests showed neutrophilia and elevated C-reactive protein. Surgical manipulation of the cited collection drained a large amount of a fetid purulent secretion. Ceftazidime and clindamycin were empirically initiated. The outcome was favorable, with fever defervescence and resolution of the scalp deformation. Culture of the drained secretion was positive for S. paucimobilis. Ciprofloxacin was scheduled for a further 10 days after discharge. The follow-up showed complete recovery. As far as we know, this is the first case of S. paucimobilis otomastoiditis, complicated with subperiosteal abscess in an immunocompetent child. The authors call attention to the increasing number of reports on S. paucimobilis infection over the years, and therefore to the importance of this pathogen, which was previously underestimated.

Histone deacetylase 4 promotes ubiquitin-dependent proteasomal degradation of Sp3 in SH-SY5Y cells treated with di(2-ethylhexyl)phthalate (DEHP), determining neuronal death

International Nuclear Information System (INIS)

Guida, Natascia; Laudati, Giusy; Galgani, Mario; Santopaolo, Marianna; Montuori, Paolo; Triassi, Maria; Di Renzo, Gianfranco; Canzoniero, Lorella M.T.; Formisano, Luigi

2014-01-01

Phthalates, phthalic acid esters, are widely used as plasticizers to produce polymeric materials in industrial production of plastics and daily consumable products. Animal studies have shown that di(2-ethylhexyl)phthalate (DEHP) may cause toxic effects in the rat brain. In the present study, chronic exposure to DEHP (0.1–100 μM) caused dose-dependent cell death via the activation of caspase-3 in neuroblastoma cells. Intriguingly, this harmful effect was prevented by the pan-histone deacetylase (HDAC) inhibitor trichostatin A, by the class II HDAC inhibitor MC-1568, but not by the class I HDAC inhibitor MS-275. Furthermore, DEHP reduced specificity protein 3 (Sp3) gene expression, but not Sp3 mRNA, after 24 and 48 h exposures. However, Sp3 protein reduction was prevented by pre-treatment with MC-1568, suggesting the involvement of class II HDACs in causing this effect. Then, we investigated the possible relationship between DEHP-induced neuronal death and the post-translational mechanisms responsible for the down-regulation of Sp3. Interestingly, DEHP-induced Sp3 reduction was associated to its deacetylation and polyubiquitination. Co-immunoprecipitation studies showed that Sp3 physically interacted with HDAC4 after DEHP exposure, while HDAC4 inhibition by antisense oligodeoxynucleotide reverted the DEHP-induced degradation of Sp3. Notably, Sp3 overexpression was able to counteract the detrimental effect induced by DEHP. Taken together, these results suggest that DEHP exerts its toxic effect by inducing deacetylation of Sp3 via HDAC4, and afterwards, Sp3-polyubiquitination. - Highlights: • Di(2-ethylhexyl)phthalate (DEHP) is cytotoxic to SH-SY5Y cells and cortical neurons. • DEHP-induced cytotoxicity is mediated by apoptosis. • DEHP-induced apoptotic cell death is inhibited by class II HDAC MC-1568. • DEHP neurotoxicity is caused by HDAC4-mediated Sp3 degradation by ubiquitin

Histone deacetylase 4 promotes ubiquitin-dependent proteasomal degradation of Sp3 in SH-SY5Y cells treated with di(2-ethylhexyl)phthalate (DEHP), determining neuronal death

Energy Technology Data Exchange (ETDEWEB)

Guida, Natascia; Laudati, Giusy [Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, “Federico II” University of Naples, Via Pansini 5, 80131 Naples (Italy); Galgani, Mario; Santopaolo, Marianna [Laboratorio di Immunologia, Istituto di Endocrinologia e Oncologia Sperimentale, Consiglio Nazionale delle Ricerche (IEOS-CNR), Napoli (Italy); Montuori, Paolo; Triassi, Maria [Department of Preventive Medical Sciences, University Federico II, Via Pansini 5, 80131 Naples (Italy); Di Renzo, Gianfranco [Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, “Federico II” University of Naples, Via Pansini 5, 80131 Naples (Italy); Canzoniero, Lorella M.T., E-mail: canzon@unisannio.it [Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, “Federico II” University of Naples, Via Pansini 5, 80131 Naples (Italy); Division of Pharmacology, Department of Science and Technology, University of Sannio, Via Port' Arsa 11, 82100 Benevento (Italy); Formisano, Luigi, E-mail: cformisa@unisannio.it [Division of Pharmacology, Department of Neuroscience, Reproductive and Odontostomatologic Sciences, School of Medicine, “Federico II” University of Naples, Via Pansini 5, 80131 Naples (Italy); Division of Pharmacology, Department of Science and Technology, University of Sannio, Via Port' Arsa 11, 82100 Benevento (Italy)

2014-10-01

Phthalates, phthalic acid esters, are widely used as plasticizers to produce polymeric materials in industrial production of plastics and daily consumable products. Animal studies have shown that di(2-ethylhexyl)phthalate (DEHP) may cause toxic effects in the rat brain. In the present study, chronic exposure to DEHP (0.1–100 μM) caused dose-dependent cell death via the activation of caspase-3 in neuroblastoma cells. Intriguingly, this harmful effect was prevented by the pan-histone deacetylase (HDAC) inhibitor trichostatin A, by the class II HDAC inhibitor MC-1568, but not by the class I HDAC inhibitor MS-275. Furthermore, DEHP reduced specificity protein 3 (Sp3) gene expression, but not Sp3 mRNA, after 24 and 48 h exposures. However, Sp3 protein reduction was prevented by pre-treatment with MC-1568, suggesting the involvement of class II HDACs in causing this effect. Then, we investigated the possible relationship between DEHP-induced neuronal death and the post-translational mechanisms responsible for the down-regulation of Sp3. Interestingly, DEHP-induced Sp3 reduction was associated to its deacetylation and polyubiquitination. Co-immunoprecipitation studies showed that Sp3 physically interacted with HDAC4 after DEHP exposure, while HDAC4 inhibition by antisense oligodeoxynucleotide reverted the DEHP-induced degradation of Sp3. Notably, Sp3 overexpression was able to counteract the detrimental effect induced by DEHP. Taken together, these results suggest that DEHP exerts its toxic effect by inducing deacetylation of Sp3 via HDAC4, and afterwards, Sp3-polyubiquitination. - Highlights: • Di(2-ethylhexyl)phthalate (DEHP) is cytotoxic to SH-SY5Y cells and cortical neurons. • DEHP-induced cytotoxicity is mediated by apoptosis. • DEHP-induced apoptotic cell death is inhibited by class II HDAC MC-1568. • DEHP neurotoxicity is caused by HDAC4-mediated Sp3 degradation by ubiquitin.

Symmetry- and Solvent-Dependent Photophysics of Fluorenes Containing Donor and Acceptor Groups (Postprint)

Science.gov (United States)

2014-07-01

for exciplex forma- tion.29,30 Solvent-dependent studies by Belfield et al. on similar dyes31 and BT2F32 revealed strong solvatochromism on the emission...Swiger, R. N.; Orseno, D. L.; Haley, J. E.; Cooper, T. M.; Tan, L.-S. Exciplex Formation in Solid State Blends of Charge-Transfer-Type Afx Dyes and...Tan, L.-S. Exciplex Formation in Blended Spin-Cast Films of Fluorene-Linked Dyes and Bisphthalimide Quenchers. J. Phys. Chem. A 2013, 117, 3909−3917

Endosulfan induced alteration in bacterial protein profile and RNA yield of Klebsiella sp. M3, Achromobacter sp. M6, and Rhodococcus sp. M2.

Science.gov (United States)

Singh, Madhu; Singh, Dileep Kumar

2014-01-30

Three bacterial strains identified as Klebsiella sp. M3, Achromobacter sp. M6 and Rhodococcus sp. M2 were isolated by soil enrichment with endosulfan followed by shake flask enrichment technique. They were efficiently degrading endosulfan in the NSM (non sulfur medium) broth. Degradation of endosulfan was faster with the cell free extract of bacterial cells grown in the sulfur deficient medium (NSM) supplemented with endosulfan than that of nutrient rich medium (Luria Bertani). In the cell free extract of NSM supplemented with endosulfan as sole sulfur source, a unique band was visualized on SDS-PAGE but not with magnesium sulfate as the sole sulfur source in NSM and LB with endosulfan. Expression of a unique polypeptide band was speculated to be induced by endosulfan under sulfur starved condition. These unique polypeptide bands were identified as OmpK35 protein, sulfate binding protein and outer membrane porin protein, respectively, in Klebsiella sp. M3, Achromobacter sp. M6 and Rhodococcus sp. M2. Endosulfan showed dose dependent negative effect on total RNA yield of bacterial strains in nutrient rich medium. Absence of plasmid DNA indicated the presence of endosulfan metabolizing gene on genomic DNA. Copyright © 2013 Elsevier B.V. All rights reserved.

Identification of genes potentially involved in solute stress response in Sphingomonas wittichii RW1 by transposon mutant recovery

Directory of Open Access Journals (Sweden)

Edith eCoronado

2014-11-01

Full Text Available The term water stress refers to the effects of low water availability on microbial growth and physiology. Water availability has been proposed as a major constraint for the use of microorganisms in contaminated sites with the purpose of bioremediation. Sphingomonas wittichii RW1 is a bacterium capable of degrading the xenobiotic compounds dibenzofuran and dibenzo-p-dioxin, and has potential to be used for targeted bioremediation. The aim of the current work was to identify genes implicated in water stress in RW1 by means of transposon mutagenesis and mutant growth experiments. Conditions of low water potential were mimicked by adding NaCl to the growth media. Three different mutant selection or separation method were tested, which, however recovered different mutants. Recovered transposon mutants with poorer growth under salt-induced water stress carried insertions in genes involved in proline and glutamate biosynthesis, and further in a gene putatively involved in aromatic compound catabolism. Transposon mutants growing poorer on medium with lowered water potential also included ones that had insertions in genes involved in more general functions such as transcriptional regulation, elongation factor, cell division protein, RNA polymerase β or an aconitase.

Valence one-electron and shake-up ionization bands of fluorene, carbazole and dibenzofuran

International Nuclear Information System (INIS)

Reza Shojaei, S.H.; Morini, Filippo; Deleuze, Michael S.

2013-01-01

Highlights: • The photoelectron spectra of the title compounds are assigned in details. • Shake-up lines are found to severely contaminate both π- and σ-ionization bands. • σ-ionization onsets are subject to severe vibronic coupling complications. • We compare the results of OVGF, ADC(3) and TDDFT calculations. - Abstract: A comprehensive study of the He (I) ultra-violet photoelectron spectra of fluorene, carbazole and dibenzofuran is presented with the aid of one-particle Green’s Function calculations employing the outer-valence Green’s Function (OVGF) approach and the third-order algebraic diagrammatic construction [ADC(3)] scheme, along with Dunning’s correlation consistent basis sets of double and triple zeta quality (cc-pVDZ, cc-pVTZ). Extrapolations of the ADC(3) results for the outermost one-electron π-ionization energies to the cc-pVTZ basis set enable theoretical insights into He (I) measurements within ∼0.15 eV accuracy, up to the σ-ionization onset. The lower ionization energy of carbazole is the combined result of mesomeric and electronic relaxation effects. OVGF/cc-pVDZ or OVGF/cc-pVTZ pole strengths smaller than 0.85 systematically corroborate a breakdown of the orbital picture of ionization at the ADC(3) level. Comparison is made with calculations of the lowest doublet–doublet excitation energies of the radical cation of fluorene, by means of time-dependent density functional theory (TDDFT)

Degradation and utilization of polycyclic aromatic hydrocarbons by indigenous soil bacteria

International Nuclear Information System (INIS)

Stetzenbach, L.D.A.

1986-01-01

The persistence of industrially derived polycyclic aromatic hydrocarbons in the subsurface may be significantly affected by the metabolism of soil bacteria. This study was conducted to determine the ability of indigenous soil bacteria to decrease the concentration of four polycyclic aromatic hydrocarbons (naphthalene, fluorene, anthracene, and pyrene) and to utilize the compounds as a substrate for growth. Soil cores from petroleum contaminated and noncontaminated sites contained 10 5 -10 7 viable microorganisms per gram dryweight of soil. Gram negative rod-shaped bacteria predominated. Decreases in the concentration of the four polycyclic aromatic hydrocarbons were observed during incubation with bacterial isolates in aqueous suspension by the use of high performance liquid chromatography. Corresponding increases in bacterial numbers indicated utilization of the compounds as a carbon source. Soil samples from the contaminated sites contained greater numbers of bacteria utilizing anthracene and pyrene than soil samples from uncontaminated sites. Degradation rates of the four polycyclic aromatic hydrocarbons were related to the compound, its concentration, and the bacterium. Biodegradation of pyrene was positively correlated with the presence of oxygen. Pyrene was biodegraded by an Acinetobacter sp. under aerobic conditions but not under anaerobic or microaerophilic conditions. Studies with radiolabeled 14 C-anthracene demonstrated utilization of the labeled carbon as a source of carbon by viable bacterial cells in aqueous suspension. Incorporation of 14 C into cellular biomass however was not observed during incubation of 14 C-anthracene in soil

Comparison of the fuel oil biodegradation potential of hydrocarbon-assimilating microorganisms isolated from a temperate agricultural soil

International Nuclear Information System (INIS)

Chaineau, C.H.; Dupont, J.; Bury, E.; Oudot, J.; Morel, J.

1999-01-01

Strains of hydrocarbon-degrading microorganisms (bacteria and fungi) were isolated from an agricultural soil in France. In a field, a portion was treated with oily cuttings resulting from the drilling of an onshore well. The cuttings which were spread at the rate of 600 g HC m -2 contained 10% of fuel oil hydrocarbons (HC). Another part of the field was left untreated. Three months after HC spreading, HC adapted bacteria and fungi were isolated at different soil depths in the two plots and identified. The biodegradation potential of the isolated strains was monitored by measuring the degradation rate of total HC, saturated hydrocarbons, aromatic hydrocarbons and resins of the fuel. Bacteria of the genera Pseudomonas, Brevundimonas, Sphingomonas, Acinetobacter, Rhodococcus, Arthrobacter, Corynebacterium and fungi belonging to Aspergillus, Penicillium, Beauveria, Acremonium, Cladosporium, Fusarium, and Trichoderma were identified. The most active strains in the assimilation of saturates and aromatics were Arthrobacter sp., Sphingomonas spiritivorum, Acinetobacter baumanii, Beauveria alba and Penicillum simplicissimum. The biodegradation potential of the hydrocarbon utilizing microorganisms isolated from polluted or unpolluted soils were similar. In laboratory pure cultures, saturated HC were more degraded than aromatic HC, whereas resins were resistant to microbial attack. On an average, individual bacterial strains were more active than fungi in HC biodegradation. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

LOGICAL AND EXPERIMENTAL DESIGN FOR PHENOL DEGRADATION USING IMMOBILIZED ACINETOBACTER SP. CULTURE

Directory of Open Access Journals (Sweden)

Amro Abd Al Fattah Amara

2010-05-01

Full Text Available Phenol degradation processes were conducted through a series of enzymatic reactions effects and is affect by different components of the microbial metabolic flux. Using different optimization strategies like mutagenesis could lead to a successful optimization but also lead to lost of some important microbial features or to release a new virulence or unexpected characters. Plackett-Burman closes much gab between optimization, safety, time, cost, Man/hr, the complexity of the metabolic flux etc. Using Plackett-Burman experimental design lead to map the points affect in the optimization process by well understanding their request from nutrient and the best environmental condition required. In this study nine variables include pH (X1, oC (X2, glucose (X3, yeast extract (X4, meat extract (X5, NH4NO3 (X6, K-salt (X7, Mg-salt (X8 and trace element (X9 are optimized during phenol degradation by Acinetobacter sp., using Plackett-Burman design method. Plackett-Burman included 16 experiments, each was used in two levels, [-1] low and high [+1]. According to Blackett-Burman design experiments the maximum degradation rate was 31.25 mg/l/h. Logical and statistical analysis of the data lead to select pH, Temperature and Meat extract as three factors affecting on phenol degradation rate. These three variables have been used in Box-Behnken experimental design for further optimization. Meat extract, which is not statistically recommended for optimization has been used while it can substitute trace element, which is statistically significant. Glucose, which is statistically significant, did not included while it has a negative effect and gave the best result at 0 g/l amount. Glucose has been completely omitted from the media.  pH, temperature and meat extract were used in fifteen experiments each was used in three levels, –1, 0, and +1 according to Box-Behnken design. Microsoft Excel 2002 solver tool was used to optimize the model created from Box-Behnken. The

Pesticide lambda-cyhalothrin degradation using mesorhizobium sp. (s1b) and bartonella sp. (s2b) strains isolated from cotton crop

International Nuclear Information System (INIS)

Chumro, W.A.; Phulpoto, A.H.; Mangi, S.; Kanhar, N.A.; Ahmed, S.; Qazi, M.A.; Pirzada, T.

2017-01-01

Lambda-cyhalothrin (LC), synthetic pyrethroid pesticide is used to control a wide range of pests in variety of agricultural fields. Pesticides are potentially harmful environmental pollutants and pose serious threat to human health. Very limited options are available for environment friendly removal of LC. Interestingly, soil microbes have been known to possess remarkable genetic makeup that helps them to perform vital job in cleaning-up harmful pollutants from the environment. In present study, two LC-degrading bacteria viz. Mesorhizobium sp. strain S1B (Accession no. gb|MF471843|) and Bartonella sp. strain S2B (Accession no. b|MF471844|) were isolated by soil enrichment technique from cotton crop soil and characterized taxonomically using conventional methods and molecular PCR-based 16S rRNA sequence homology. The bacterial strains S1B and S2B achieved 29% and 40% removal of LC (conc. 250 mg/L, w/v), with maximum growth absorbance (OD) of 1.19 +- 0.06 and 1.13+- 0.09, respectively, during 20 days of incubation at 30 degree C and agitation 200 rpm under experimental laboratory circumstances. The percent removal of LC was estimated using UV-Vis Spectroscopy at 287 nm (? max) against the standard curve plotted at different LC concentrations. The bacterial isolates of present study have exhibited substantial efficiency for environmental biodegradation of the pesticide. (author)

Bioremediation of crude oil waste contaminated soil using petrophilic consortium and Azotobacter sp.

Directory of Open Access Journals (Sweden)

M. Fauzi

2016-01-01

Full Text Available This study was aimed to determine the effect Petrophilic and Azotobacter sp. consortium on the rate of degradation of hydrocarbons, Azotobacter growth, and Petrophilic fungi growth in an Inceptisol contaminated with crude oil waste originating from Balongan refinery, one of Pertamina (Indonesia’s largest state-owned oil and gas company units in Indramayu – West Java. This study was conducted from March to April 2014 in the glasshouse of research station of the Faculty of Agriculture, Padjadjaran University at Ciparanje, Jatinangor District, Sumedang Regency of West Java. This study used a factorial completely randomized design with two treatments. The first treatment factor was Petrophilic microbes (A consisting of four levels (without treatment, 2% Petrophilic fungi, 2% Petrophilic bacteria, and the 2% Petrophilic consortium, and Azotobacter sp. The second treatment factor was Azotobacter sp. (B consisting of four levels (without treatment, 0.5%, Azotobacter sp., 1% Azotobacter sp., and 1.5% Azotobacter sp. The results demonstrated interaction between Petrophilic microbes and Azotobacter sp. towards hydrocarbon degradation rate, but no interaction was found towards the growth rate of Azotobacter sp. and Petrophilic fungi. Treatments of a1b3 (2% consortium of Petrophilic fungi with 1.5% Azotobacter sp. and a3b3 (2% Petrophilic consortium and 1.5% Azotobacter sp. had hydrocarbon degradation rate at 0.22 ppm/day for each treatment, showing the highest hydrocarbon degradation rate.

Characterisation of the simultaneous molybdenum reduction and glyphosate degradation by Burkholderia vietnamiensis AQ5-12 and Burkholderia sp. AQ5-13.

Science.gov (United States)

Manogaran, Motharasan; Ahmad, Siti Aqlima; Yasid, Nur Adeela; Yakasai, Hafeez Muhammad; Shukor, Mohd Yunus

2018-02-01

In this novel study, we report on the use of two molybdenum-reducing bacteria with the ability to utilise the herbicide glyphosate as the phosphorus source. The bacteria reduced sodium molybdate to molybdenum blue (Mo-blue), a colloidal and insoluble product, which is less toxic. The characterisation of the molybdenum-reducing bacteria was carried out using resting cells immersed in low-phosphate molybdenum media. Two glyphosate-degrading bacteria, namely Burkholderia vietnamiensis AQ5-12 and Burkholderia sp. AQ5-13, were able to use glyphosate as a phosphorous source to support molybdenum reduction to Mo-blue. The bacteria optimally reduced molybdenum between the pHs of 6.25 and 8. The optimum concentrations of molybdate for strain Burkholderia vietnamiensis strain AQ5-12 was observed to be between 40 and 60 mM, while for Burkholderia sp. AQ5-13, the optimum molybdate concentration occurred between 40 and 50 mM. Furthermore, 5 mM of phosphate was seen as the optimum concentration supporting molybdenum reduction for both bacteria. The optimum temperature aiding Mo-blue formation ranged from 30 to 40 °C for Burkholderia vietnamiensis strain AQ5-12, whereas for Burkholderia sp. AQ5-13, the range was from 35 to 40 °C. Glucose was the best electron donor for supporting molybdate reduction, followed by sucrose, fructose and galactose for both strains. Ammonium sulphate was the best nitrogen source in supporting molybdenum reduction. Interestingly, increasing the glyphosate concentrations beyond 100 and 300 ppm for Burkholderia vietnamiensis strain AQ5-12 and Burkholderia sp. AQ5-13, respectively, significantly inhibited molybdenum reduction. The ability of these bacteria to reduce molybdenum while degrading glyphosate is a useful process for the bioremediation of both toxicants.

Draft Genome Sequence of Paenibacillus sp. Strain DMB20, Isolated from Alang Ship-Breaking Yard, Which Harbors Genes for Xenobiotic Degradation.

Science.gov (United States)

Shah, Binal; Jain, Kunal; Patel, Namrata; Pandit, Ramesh; Patel, Anand; Joshi, Chaitanya G; Madamwar, Datta

2015-06-11

Paenibacillus sp. strain DMB20, in cometabolism with other Proteobacteria and Firmicutes, exhibits azoreduction of textile dyes. Here, we report the draft genome sequence of this bacterium, consisting of 6,647,181 bp with 7,668 coding sequences (CDSs). The data presented highlight multiple sets of functional genes associated with xenobiotic compound degradation. Copyright © 2015 Shah et al.

Biodegradation of sulfosulphuron in agricultural soil by Trichoderma sp.

Science.gov (United States)

Yadav, U; Choudhury, P P

2014-11-01

Sulfosulphuron-degrading fungus was isolated by enrichment technique from the sulfosulphuron-contaminated soil of wheat rhizosphere. To assess the biodegradation potential of isolated Trichoderma sp., minimal potato dextrose agar broth with different levels of sulfosulphuron (up to 2 g l(-1) ) was evaluated in the growth and biotransformation experiments. ESI LC-MS/MS analysis revealed the presence of degradation products 2-amino-4,6-dimethoxypyrimidine (I) and 2-ethylsulfonyl imidazo{1,2-a} pyridine-3-sulfonamide-2-ethylsulfonyl imidazo{1,2-a} pyridine-3-sulfonamide (II) indicating the cleavage of the urea bridge and the presence of the by-product N-(4,6-dimethoxypyrimidin-2-yl)urea (III) indicating the degradation of sulfonylamide linkage. Two other metabolites, N-(4,6-dimethoxypyrimidin-2-yl)-N'-hydroxyurea (IV) and N, N'-bis(4,6-dimethoxypyrimidin-2-yl)urea (V), were also identified. From the previous reports, it was found that the degradation of sulfonyl urea herbicides took place through the chemical degradation of the sulfonylurea bridge followed by microbial degradation. During this investigation, Trichoderma sp. grew well with and degraded sulfosulphuron via both the decarboxylation on the sulphonyl urea bridge and the hydrolytic cleavage of the sulfonylamide linkage as demonstrated by the formation of metabolites. Trichoderma is nonphytopathogenic in nature, and some species of it restrict the growth of soil-dwelling phytopathogens. Therefore, it is a promising candidate for the decontamination of soil from sulfosulphuron residues. The degradation of sulfosulphuron by any individual fungus is being reported for the first time. Trichoderma sp. isolated from wheat-rhizospheric soil could survive in minimal broth rich in sulfosulphuron. Previous reports have described the complete degradation of any sulfonyl urea herbicides by micro-organisms only after the pH-dependent chemical hydrolysis of the sulfonyl urea bridge of the herbicide. This study

A new selective fluorene-based fluorescent internal charge transfer (ICT) sensor for sugar alcohols in aqueous solution.

Science.gov (United States)

Hosseinzadeh, Rahman; Mohadjerani, Maryam; Pooryousef, Mona

2016-03-01

Sugar alcohols, such as sorbitol, are commonly used as a replacement for sucrose in the food industry, applied as starting material for vitamin C synthesis, and involved as one of the causative factors in diabetic complications. Therefore, their detection and quantification in aqueous solution are necessary. The reversible covalent interactions between boronic acids and diols are the basis of efficient methods for the detection of saccharides. Herein, we report a new internal charge transfer (ICT) fluorene-based fluorescent boronic acid sensor (1) 2-[(9,9-dimethyl-9H-fluoren-2-yl-amino)methyl] phenyl boronic acid that shows significant fluorescence changes upon addition of saccharides. The boronic acid has high affinity (K a = 1107.9 M(-1)) and selectivity for sorbitol at pH = 8.31. It showed a linear response toward sorbitol in the concentration range from 1.0 × 10(-5) to 6.0 × 10(-4) mol L(-1) with the detection limit of 7.04 × 10(-6) mol L(-1). Sensor 1 was used to detect sorbitol in real samples with good recovery.

Biodegradation of 2-nitrotoluene by Micrococcus sp. strain SMN-1.

Science.gov (United States)

Mulla, Sikandar I; Hoskeri, Robertcyril S; Shouche, Yogesh S; Ninnekar, Harichandra Z

2011-02-01

A bacterial consortium capable of degrading nitroaromatic compounds was isolated from pesticide-contaminated soil samples by selective enrichment on 2-nitrotoluene as a sole source of carbon and energy. The three different bacterial isolates obtained from bacterial consortium were identified as Bacillus sp. (A and C), Bacillus flexus (B) and Micrococcus sp. (D) on the basis of their morphological and biochemical characteristics and by phylogenetic analysis based on 16S rRNA gene sequences. The pathway for the degradation of 2-nitrotoluene by Micrococcus sp. strain SMN-1 was elucidated by the isolation and identification of metabolites, growth and enzymatic studies. The organism degraded 2-nitrotoluene through 3-methylcatechol by a meta-cleavage pathway, with release of nitrite.

Evidence for cooperative mineralization of diuron by Arthrobacter sp. BS2 and Achromobacter sp. SP1 isolated from a mixed culture enriched from diuron exposed environments.

Science.gov (United States)

Devers-Lamrani, Marion; Pesce, Stéphane; Rouard, Nadine; Martin-Laurent, Fabrice

2014-12-01

Diuron was found to be mineralized in buffer strip soil (BS) and in the sediments (SED) of the Morcille river in the Beaujolais vineyard repeatedly treated with this herbicide. Enrichment cultures from BS and SED samples led to the isolation of three bacterial strains transforming diuron to 3,4-dichloroaniline (3,4-DCA) its aniline derivative. 16S rRNA sequencing revealed that they belonged to the genus Arthrobacter (99% of similarity to Arthrobacter globiformis strain K01-01) and were designated as Arthrobacter sp. BS1, BS2 and SED1. Diuron-degrading potential characterized by sequencing of the puhA gene, characterizing the diuron-degradaing potential, revealed 99% similarity to A. globiformis strain D47 puhA gene isolated a decade ago in the UK. These isolates were also able to use chlorotoluron for their growth. Although able to degrade linuron and monolinuron to related aniline derivatives they were not growing on them. Enrichment cultures led to the isolation of a strain from the sediments entirely degrading 3,4-DCA. 16S rRNA sequence analysis showed that it was affiliated to the genus Achromobacter (99% of similarity to Achromobacter sp. CH1) and was designated as Achromobacter sp. SP1. The dcaQ gene encoding enzyme responsible for the transformation of 3,4-DCA to chlorocatechol was found in SP1 with 99% similarity to that of Comamonas testosteroni WDL7. This isolate also used for its growth a range of anilines (3-chloro-4-methyl-aniline, 4-isopropylaniline, 4-chloroaniline, 3-chloroaniline, 4-bromoaniline). The mixed culture composed of BS2 and SP1 strains entirely mineralizes (14)C-diuron to (14)CO2. Diuron-mineralization observed in the enrichment culture could result from the metabolic cooperation between these two populations. Copyright © 2014. Published by Elsevier Ltd.

Biodegradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1.

Science.gov (United States)

Tallur, Preeti N; Mulla, Sikandar I; Megadi, Veena B; Talwar, Manjunatha P; Ninnekar, Harichandra Z

2015-01-01

Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF), polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM) than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water.

Biodegradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1

Directory of Open Access Journals (Sweden)

Preeti N. Tallur

2015-09-01

Full Text Available Pyrethroid pesticide cypermethrin is a environmental pollutant because of its widespread use, toxicity and persistence. Biodegradation of such chemicals by microorganisms may provide an cost-effective method for their detoxification. We have investigated the degradation of cypermethrin by immobilized cells of Micrococcus sp. strain CPN 1 in various matrices such as, polyurethane foam (PUF, polyacrylamide, sodium alginate and agar. The optimum temperature and pH for the degradation of cypermethrin by immobilized cells of Micrococcus sp. were found to be 30 °C and 7.0, respectively. The rate of degradation of 10 and 20 mM of cypermethrin by freely suspended cells were compared with that of immobilized cells in batches and semi-continuous with shaken cultures. PUF-immobilized cells showed higher degradation of cypermethrin (10 mM and 20 mM than freely suspended cells and cells immobilized in other matrices. The PUF-immobilized cells of Micrococcus sp. strain CPN 1 were retain their degradation capacity. Thus, they can be reused for more than 32 cycles, without losing their degradation capacity. Hence, the PUF-immobilized cells of Micrococcus sp. could potentially be used in the bioremediation of cypermethrin contaminated water.

Specific growth rate plays a critical role in hydrogen peroxide resistance of the marine oligotrophic ultramicrobacterium Sphingomonas alaskensis strain RB2256

NARCIS (Netherlands)

Ostrowski, M; Cavicchioli, R; Gottschal, JC; Blaauw, Maarten

The marine oligotrophic ultramicrobacterium Sphingomonas alaskensis RB2256 has a physiology that is distinctly different from that of typical copiotrophic marine bacteria, such as Vibrio angustum S14. This includes a high level of inherent stress resistance and the absence of starvation-induced

Characterization of hydrocarbon-degrading and biosurfactant-producing Pseudomonas sp. P-1 strain as a potential tool for bioremediation of petroleum-contaminated soil.

Science.gov (United States)

Pacwa-Płociniczak, Magdalena; Płaza, Grażyna Anna; Poliwoda, Anna; Piotrowska-Seget, Zofia

2014-01-01

The Pseudomonas sp. P-1 strain, isolated from heavily petroleum hydrocarbon-contaminated soil, was investigated for its capability to degrade hydrocarbons and produce a biosurfactant. The strain degraded crude oil, fractions A5 and P3 of crude oil, and hexadecane (27, 39, 27 and 13% of hydrocarbons added to culture medium were degraded, respectively) but had no ability to degrade phenanthrene. Additionally, the presence of gene-encoding enzymes responsible for the degradation of alkanes and naphthalene in the genome of the P-1 strain was reported. Positive results of blood agar and methylene blue agar tests, as well as the presence of gene rhl, involved in the biosynthesis of rhamnolipid, confirmed the ability of P-1 for synthesis of glycolipid biosurfactant. 1H and 13C nuclear magnetic resonance, Fourier transform infrared spectrum and mass spectrum analyses indicated that the extracted biosurfactant was affiliated with rhamnolipid. The results of this study indicate that the P-1 and/or biosurfactant produced by this strain have the potential to be used in bioremediation of hydrocarbon-contaminated soils.

Degradation of morpholine by Mycobacterium sp. isolated from ...

African Journals Online (AJOL)

Jane

2011-08-08

Aug 8, 2011 ... Full Length Research Paper. Degradation ... The heterocyclic xenobiotic compound morpholine (1- ... Culture of morpholine degrading microorganisms ..... Biodegradation and toxicity of selected amines on aquatic organisms.

Fermentative degradation of polyethylene glycol by a strictly anaerobic, gram-negative, nonsporeforming bacterium, Pelobacter venetianus sp. nov.

Science.gov (United States)

Schink, B; Stieb, M

1983-06-01

The synthetic polyether polyethylene glycol (PEG) with a molecular weight of 20,000 was anaerobically degraded in enrichment cultures inoculated with mud of limnic and marine origins. Three strains (Gra PEG 1, Gra PEG 2, and Ko PEG 2) of rod-shaped, gram-negative, nonsporeforming, strictly anaerobic bacteria were isolated in mineral medium with PEG as the sole source of carbon and energy. All strains degraded dimers, oligomers, and polymers of PEG up to a molecular weight of 20,000 completely by fermentation to nearly equal amounts of acetate and ethanol. The monomer ethylene glycol was not degraded. An ethylene glycol-fermenting anaerobe (strain Gra EG 12) isolated from the same enrichments was identified as Acetobacterium woodii. The PEG-fermenting strains did not excrete extracellular depolymerizing enzymes and were inhibited by ethylene glycol, probably owing to a blocking of the cellular uptake system. PEG, some PEG-containing nonionic detergents, 1,2-propanediol, 1,2-butanediol, glycerol, and acetoin were the only growth substrates utilized of a broad variety of sugars, organic acids, and alcohols. The isolates did not reduce sulfate, sulfur, thiosulfate, or nitrate and were independent of growth factors. In coculture with A. woodii or Methanospirillum hungatei, PEGs and ethanol were completely fermented to acetate (and methane). A marine isolate is described as the type strain of a new species, Pelobacter venetianus sp. nov. Its physiology and ecological significance, as well as the importance and possible mechanism of anaerobic polyether degradation, are discussed.

Blue-light-emitting organic electroluminescence via exciplex emission based on a fluorene derivative

International Nuclear Information System (INIS)

Li Fushan; Chen Zhijian; Wei Wei; Cao Huayu; Gong Qihuang; Teng Feng; Qian Lei; Wang Yuanmin

2004-01-01

The synthesis of a high photoluminescence efficiency (88%, compared with tris(8-hydroxyquinoline)(Alq 3 )) organic material 9,9-Dibutyl-N,N,N,N-tetraphenyl-9H-fluorene-2,7-diamine (DTFD) via Ullmann condensation was reported. Exiciplex emission of the ITO/DTFD/2,2-[1,2-phenylenebis(oxy)]bis(N,N-diphenylacetamide)/Alq 3 /LiF/Al device was observed and the peak wavelength of the emission was measured to be 480 nm, which belongs to the blue region. A turn-on voltage as low as 4 V and maximal brightness as large as 400 cd m -2 were measured. The electroluminescence spectrum was observed to be blue-shifted with increase in applied voltage

Blue-light-emitting organic electroluminescence via exciplex emission based on a fluorene derivative

Energy Technology Data Exchange (ETDEWEB)

Li Fushan [Department of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, Peking University, 100871 (China); Chen Zhijian [Department of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, Peking University, 100871 (China); Wei Wei [Department of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, Peking University, 100871 (China); Cao Huayu [Department of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, Peking University, 100871 (China); Gong Qihuang [Department of Physics, State Key Laboratory for Artificial Microstructures and Mesoscopic Physics, Peking University, 100871 (China); Teng Feng [Institute of Optoelectronic Technology, Northern Jiaotong University, Beijing 100044 (China); Qian Lei [Institute of Optoelectronic Technology, Northern Jiaotong University, Beijing 100044 (China); Wang Yuanmin [Institute of Optoelectronic Technology, Northern Jiaotong University, Beijing 100044 (China)

2004-06-21

The synthesis of a high photoluminescence efficiency (88%, compared with tris(8-hydroxyquinoline)(Alq{sub 3})) organic material 9,9-Dibutyl-N,N,N,N-tetraphenyl-9H-fluorene-2,7-diamine (DTFD) via Ullmann condensation was reported. Exiciplex emission of the ITO/DTFD/2,2-[1,2-phenylenebis(oxy)]bis(N,N-diphenylacetamide)/Alq{sub 3}/LiF/Al device was observed and the peak wavelength of the emission was measured to be 480 nm, which belongs to the blue region. A turn-on voltage as low as 4 V and maximal brightness as large as 400 cd m{sup -2} were measured. The electroluminescence spectrum was observed to be blue-shifted with increase in applied voltage.

Isolation and characterization of an acrylamide-degrading yeast Rhodotorula sp. strain MBH23 KCTC 11960BP.

Science.gov (United States)

Rahim, M B H; Syed, M A; Shukor, M Y

2012-10-01

As well as for chemical and environmental reasons, acrylamide is widely used in many industrial applications. Due to its carcinogenicity and toxicity, its discharge into the environment causes adverse effects on humans and ecology alike. In this study, a novel acrylamide-degrading yeast has been isolated. The isolate was identified as Rhodotorula sp. strain MBH23 using ITS rRNA analysis. The results showed that the best carbon source for growth was glucose at 1.0% (w/v). The optimum acrylamide concentration, being a nitrogen source for cellular growth, was at 500 mg l(-1). The highest tolerable concentration of acrylamide was 1500 mg l(-1) whereas growth was completely inhibited at 2000 mg l(-1). At 500 mg l(-1), the strain MBH completely degraded acrylamide on day 5. Acrylic acid as a metabolite was detected in the media. Strain MBH23 grew well between pH 6.0 and 8.0 and between 27 and 30 °C. Amides such as 2-chloroacetamide, methacrylamide, nicotinamide, acrylamide, acetamide, and propionamide supported growth. Toxic heavy metals such as mercury, chromium, and cadmium inhibited growth on acrylamide. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Novel insight into the genetic context of the cadAB genes from a 4-chloro-2-methylphenoxyacetic acid-degrading Sphingomonas

DEFF Research Database (Denmark)

Nielsen, Tue Kjærgaard; Xu, Zhuofei; Gozdereliler, Erkin

2013-01-01

of IS3 elements. The canonical tfdA alpha-gene of group III 2,4-D degraders, encoding the first step in degradation of 2,4-D and related compounds, was not present in the chromosomal contigs. However, the alternative cadAB genes, also providing the initial degradation step, were found in Tn6228, along...... with the 2,4-D-degradation-associated genes tfdBCDEFKR and cadR. Putative reductase and ferredoxin genes cadCD of Rieske non-heme iron oxygenases were also present in close proximity to cadAB, suggesting that these might have an unknown role in the initial degradation reaction. Parts of the composite...

Solar-energy production and energy-efficient lighting: photovoltaic devices and white-light-emitting diodes using poly(2,7-fluorene), poly(2,7-carbazole), and poly(2,7-dibenzosilole) derivatives.

Science.gov (United States)

Beaupré, Serge; Boudreault, Pierre-Luc T; Leclerc, Mario

2010-02-23

World energy needs grow each year. To address global warming and climate changes the search for renewable energy sources with limited greenhouse gas emissions and the development of energy-efficient lighting devices are underway. This Review reports recent progress made in the synthesis and characterization of conjugated polymers based on bridged phenylenes, namely, poly(2,7-fluorene)s, poly(2,7-carbazole)s, and poly(2,7-dibenzosilole)s, for applications in solar cells and white-light-emitting diodes. The main strategies and remaining challenges in the development of reliable and low-cost renewable sources of energy and energy-saving lighting devices are discussed.

A new processable electrochromic polymer based on an electron deficient fluorene derivative with a high coloration efficiency

International Nuclear Information System (INIS)

Çarbaş, Buket Bezgin; Kivrak, Arif; Önal, Ahmet M.

2011-01-01

Highlights: ► Electrochemical synthesis and elecroptical properties of a new soluble polymer based on fluorenone and 3,4-propylenedioxythiophene are highlighted. ► The polymer film exhibits reversible electrochromic behavior and both p and n dopable. ► In addition it has high electrochemical stability and coloration efficiency. ► In THF, polymer film emits orange light when excited at 355 nm. - Abstract: A new fluorenone based soluble polymer, namely poly(2,7-bis-(3,3-dihexyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl) -fluoren-9-one) (PPFP), containing propylenedioxythiophene (ProDOT) as a donor and fluorenone (FO) as an acceptor group is highlighted. Electrochemical polymerization of 2,7-bis-(3,3-dihexyl-3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-6-yl) -fluoren-9-one (PFP) was achieved in dichloromethane/acetonitrile mixture with 0.1 M tetrabutylammonium hexafluorophosphate via potential cycling. The polymer shows an electrochromic behavior, a color change from orange to dark blue during oxidation with a high coloration efficiency (422 cm 2 /C at 684 nm) and orange to yellow during reduction with high optical and electrochemical stability as compared to its close analogues, in addition it is found to be both p and n dopable. Furthermore, this soluble polymer exhibits fluorescent properties (the emission of orange light (578 nm) in THF solution).

Soluble Electrochromic Polymers Incorporating Benzoselenadiazole and Electron Donor Units (Carbazole or Fluorene: Synthesis and Electronic-Optical Properties

Directory of Open Access Journals (Sweden)

Jianzhong Xu

2018-04-01

Full Text Available A series of π-conjugated polymers containing alternating benzoselenadiazole (BSe-bi(thiophene derivative-carbazole or benzoththiadiazole (BSe-bi(thiophene derivative-fluorene units were designed and synthesized. Thiophene derivatives, namely 3-hexylthiophene, 3,4-bihexyloxythiophene, and 3,4-bioctyloxythiophene, were used as the π-bridges of the polymers. The polymers were characterized in detail in terms of their thermal stabilities, cyclic voltammograms, UV-Vis absorption, spectroelectrochemistry, dynamic switching property and so forth. The alkoxy thiophene π-bridged polymers have lower onset oxidation potentials and bandgaps than that of their corresponding alkyl thiophene π-bridged polymers. The selection of the donor units between the carbazole and the fluorene units has nearly no effect on the bandgaps and colors as well as the onset oxidation potentials of the polymers. The increase in the length of the side alkyl chains on the thiophene ring caused a slight increase in the polymer bandgap, which may be caused by the space hindrance effect. The dynamic switching abilities of the polymers were obtained by the chronoabsorptometry method, and the results also suggested that the alkoxy thiophene-containing polymers (as π-bridges have higher contrast ratios than the corresponding alkyl thiophene-containing polymers. Furthermore, the increase in the length of the side alkyl chain might have a detrimental effect on the optical contrast ratios of the polymers.

Conjugated Polymers Containing BODIPY and Fluorene Units for Sensitive Detection of CN− Ions: Site-Selective Synthesis, Photo-Physical and Electrochemical Properties

Directory of Open Access Journals (Sweden)

Tian He

2017-10-01

Full Text Available Conjugated polymers containing distinct molecular units are expected to be very interesting because of their unique properties endowed by these units and the formed conjugated polymers. Herein, four new conjugated copolymers based on fluorene and 4,4’-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY have been designed and synthesized via Sonogashira polymerization. The fluorene unit was attached to the 3,5- or 2,6-positions of BODIPY by ethynylenes or p-diacetylenebenzene. The obtained polymers show good thermal stability and broad absorption in the wavelength range from 300 to 750 nm. The effects of site-selective copolymerization and conjugation length along the polymer backbone on the optoelectronic and electrochemical properties of these copolymers were systematically studied by UV-Vis spectroscopy, photoluminescence (PL and cyclic voltammetry. Besides, it is found that the BODIPY-based copolymers exhibit selectively sensitive responses to cyanide anions, resulting in obvious change of UV-Vis absorption spectra and significant fluorescence quenching of the polymers among various common anions.

Novel Chryseobacterium sp. PYR2 degrades various organochlorine pesticides (OCPs) and achieves enhancing removal and complete degradation of DDT in highly contaminated soil.

Science.gov (United States)

Qu, Jie; Xu, Yang; Ai, Guo-Min; Liu, Ying; Liu, Zhi-Pei

2015-09-15

Long term residues of organochlorine pesticides (OCPs) in soils are of great concerning because they seriously threaten food security and human health. This article focuses on isolation of OCP-degrading strains and their performance in bioremediation of contaminated soil under ex situ conditions. A bacterium, Chryseobacterium sp. PYR2, capable of degrading various OCPs and utilizing them as a sole carbon and energy source for growth, was isolated from OCP-contaminated soil. In culture experiments, PYR2 degraded 80-98% of hexachlorocyclohexane (HCH) or 1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane (DDT) isomers (50 mg L(-1)) in 30 days. A pilot-scale ex situ bioremediation study of highly OCP-contaminated soil augmented with PYR2 was performed. During the 45-day experimental period, DDT concentration was reduced by 80.3% in PYR2-augmented soils (35.37 mg kg(-1) to 6.97 mg kg(-1)) but by only 57.6% in control soils. Seven DDT degradation intermediates (metabolites) were detected and identified in PYR2-augmented soils: five by GC/MS: 1,1-dichloro-2,2-bis (4-chlorophenyl) ethane (DDD), 1,1-dichloro-2,2-bis (4-chlorophenyl) ethylene (DDE), 1-chloro-2,2-bis (4-chlorophenyl) ethylene (DDMU), 1-chloro-2,2-bis (4-chlorophenyl) ethane (DDMS), and dichlorobenzophenone (DBP); and two by LC/MS: 4-chlorobenzoic acid (PCBA) and 4-chlorophenylacetic acid (PCPA). Levels of metabolites were fairly stable in control soils but varied greatly with time in PYR2-augmented soils. Levels of DDD, DDMU, and DDE in PYR2-augmented soils increased from day 0 to day 30 and then decreased by day 45. A DDT biodegradation pathway is proposed based on our identification of DDT metabolites in PYR2-augmented systems. PYR2 will be useful in future studies of OCP biodegradation and in bioremediation of OCP-contaminated soils. Copyright © 2015 Elsevier Ltd. All rights reserved.

Synthesis of electro-optically active polymer composite of poly[2,2'-bis(3,4-ethylenedioxythiophene-alt-fluorene]/hydroxypropyl cellulose showing liquid crystal structure

Directory of Open Access Journals (Sweden)

N. Eguchi

2017-10-01

Full Text Available Electrochemical preparation of a composite consisting of poly[2,2′-bis(3,4-ethylenedioxythiophene-alt-fluorene] and hydroxypropyl cellulose (PEFE/HPC was carried out. We conducted electrochemical polymerization of poly[2,2′-bis(3,4-ethylenedioxythiophene-alt-fluorene] (EFE as a monomer in a lyotropic liquid crystal of HPC. We used an organic solvent instead of water for lyotropic liquid crystal medium to expand the possibility of the range of monomers, although water is usually employed as a solvent for HPC for showing liquid crystallinity. Here, we employed N,N-dimethylformamide (DMF as a solvent for HPC. Electrochemical polymerization in the polymer liquid crystal was carried out to obtain a polymer film with liquid crystal order. The polymer film thus prepared exhibited optical activity. Fourier transfer infrared (FT-IR absorption spectroscopy reveals that the film is a composite consisting of HPC and polymer. The composite PEFE/HPC thus prepared in HPC/DMF system showed electrochromism.

Degradation of β-Aryl Ether Bonds in Transgenic Plants

DEFF Research Database (Denmark)

Mnich, Ewelina

Lignin is one of the main building blocks of the plant cell wall. It tethers the cell wall by cross-linking with polysaccharides conferring mechanical strength to plants, aiding water transport and providing a mechanical barrier against pathogens. It is generated by the polymerization....... Compared to other plants grass cell walls contain elevated amount of ferulates which play a crucial role in cross-linking of polysaccharides and lignin. In addition ferulates are believed to be nucleation cites for the lignification. The bacterium Sphingomonas paucimobilis SYK6 has developed an enzyme...... of the cell wall. The aim of the study was to alter lignin structure by expression in plants of the enzymes from S. paucimobilis involved in ether bond degradation (LigDFG). Arabidopsis thaliana and Brachypodium distachyon transgenic lines were generated and characterized with respect to lignin structure...

Sphingomonas paucimobilis bacteraemia and shock in a patient with rheumatic carditis

Directory of Open Access Journals (Sweden)

Y Yozgat

2014-01-01

Full Text Available Acute rheumatic fever (ARF carditis is treated with steroids, which can cause changes in the cellular immune response, especially decreased CD3 (+ T cells. Nosocomial infections due to steroid use for treatment of ARF carditis or secondary to the changes in the cellular immune response have not been reported in the literature. Sphingomonas paucimobilis is a Gram-negative bacillus causing community- and hospital-acquired infections. It has been reported as causing bacteraemia/sepsis, pneumonia or peritonitis in patients with malignancies, immunosuppression or diabetes. We present a case with S. paucimobilis bacteraemia/sepsis and shock after administration of steroids for treatment of ARF carditis. We suggest early identification of the causative agent and appropriate adjustments of the treatment plan to avoid shock and possible mortality. This is the first reported case of S. paucimobilis bacteraemia/sepsis in the setting of steroid use for ARF carditis.

The role of heterotrophic microorganism Galactomyces sp. Z3 in improving pig slurry bioleaching.

Science.gov (United States)

Zhou, Jun; Zheng, Guanyu; Zhou, Lixiang; Liu, Fenwu; Zheng, Chaocheng; Cui, Chunhong

2013-01-01

The feasibility of removing heavy metals and eliminating pathogens from pig slurry through bioleaching involving the fungus Galactomyces sp. Z3 and two acidophilic thiobacillus (A. ferrooxidans LX5 and A. thiooxidans TS6) was investigated. It was found that the isolated pig slurry dissolved organic matter (DOM) degrader Z3 was identified as Galactomyces sp. Z3, which could grow well at pH 2.5-7 and degrade pig slurry DOM from 1973 to 942 mg/l within 48 h. During the successive multi-batch bioleaching systems, the co-inoculation of pig slurry degrader Galactomyces sp. Z3 and the two Acidithiobacillus species could improve pig slurry bioleaching efficiency compared to the single system without Galactomyces sp. Z3. The removal efficiency of Zn and Cu exceeded 94% and 85%, respectively. In addition, the elimination efficiencies of pathogens, including both total coliform and faecal coliform counts, exceeded 99% after bioleaching treatment. However, the counts of Galactomyces sp. Z3 decreased with the fall of pH and did not restore to the initial level during successive multi-batch bioleaching systems, and it is necessary to re-inoculate Galactomyces sp. Z3 cells into the bioleaching system to maintain its role in degrading pig slurry DOM. Therefore, a bioleaching technique involving both Galactomyces sp. Z3 and Acidithiobacillus species is an efficient method for removing heavy metals and eliminating pathogens from pig slurry.

Destruction of acenaphthene, fluorene, anthracene and pyrene by a dc gliding arc plasma reactor

International Nuclear Information System (INIS)

Yu Liang; Tu Xin; Li Xiaodong; Wang Yu; Chi Yong; Yan Jianhua

2010-01-01

In this study, four kinds of PAHs (polycyclic aromatic hydrocarbons) i.e. acenaphthene, fluorene, anthracene and pyrene are used as targets for investigation of PAHs treatment process assisted by dc gliding arc discharge. The effects of carrier gas and external resistance on the PAHs decomposition process are discussed. The results indicate that the destruction rate can be achieved to the highest with the carrier gas of oxygen and the external resistance of 50 kΩ independent of type of PAHs. Furthermore, experimental results suggest that destruction energy efficiency of gliding arc plasma would be improved by treating higher concentration pollutants. Based on the analysis of experimental results, possible destruction mechanisms in different gas discharge are discussed.

Microbial characterization of toluene-degrading denitrifying consortia obtained from terrestrial and marine ecosystems.

Science.gov (United States)

An, Y-J; Joo, Y-H; Hong, I-Y; Ryu, H-W; Cho, K-S

2004-10-01

The degradation characteristics of toluene coupled to nitrate reduction were investigated in enrichment culture and the microbial communities of toluene-degrading denitrifying consortia were characterized by denaturing gradient gel electrophoresis (DGGE) technique. Anaerobic nitrate-reducing bacteria were enriched from oil-contaminated soil samples collected from terrestrial (rice field) and marine (tidal flat) ecosystems. Enriched consortia degraded toluene in the presence of nitrate as a terminal electron acceptor. The degradation rate of toluene was affected by the initial substrate concentration and co-existence of other hydrocarbons. The types of toluene-degrading denitrifying consortia depended on the type of ecosystem. The clone RS-7 obtained from the enriched consortium of the rice field was most closely related to a toluene-degrading and denitrifying bacterium, Azoarcus denitrificians (A. tolulyticus sp. nov.). The clone TS-11 detected in the tidal flat enriched consortium was affiliated to Thauera sp. strain S2 (T. aminoaromatica sp. nov.) that was able to degrade toluene under denitrifying conditions. This indicates that environmental factors greatly influence microbial communities obtained from terrestrial (rice field) and marine (tidal flat) ecosystems.

Isolation of Asphaltene-Degrading Bacteria from Sludge Oil

Directory of Open Access Journals (Sweden)

Pingkan Aditiawati

2015-03-01

Full Text Available Sludge oil contains 30%–50% hydrocarbon fractions that comprise saturated fractions, aromatics, resins, and asphaltene. Asphaltene fraction is the most persistent fraction. In this research, the indigenous bacteria that can degrade asphaltene fractions from a sludge oil sample from Balikpapan that was isolated using BHMS medium (Bushnell-Hass Mineral Salt with 0.01% (w/v yeast extract, 2% (w/v asphaltene extract, and 2% (w/v sludge oil. The ability of the four isolates to degrade asphaltene fractions was conducted by the biodegradation asphaltene fractions test using liquid cultures in a BHMS medium with 0.01% (w/v yeast extract and 2% (w/v asphaltene extract as a carbon source. The parameters measured during the process of biodegradation of asphaltene fractions include the quantification of Total Petroleum Hydrocarbon (g, log total number of bacteria (CFU/ml, and pH. There are four bacteria (isolates 1, 2, 3, and 4 that have been characterized to degrade asphaltic fraction and have been identified as Bacillus sp. Lysinibacillus fusiformes, Acinetobacter sp., and Mycobacterium sp., respectively. The results showed that the highest ability to degrade asphaltene fractions is that of Bacillus sp. (isolate 1 and Lysinibacillus fusiformes (Isolate 2, with biodegradation percentages of asphaltene fractions being 50% and 55%, respectively, and growth rate at the exponential phase is 7.17x107 CFU/mL.days and 4.21x107 CFU/mL.days, respectively.

Degradation of slime extracellular polymeric substances and inhibited sludge flocs destruction contribute to sludge dewaterability enhancement during fungal treatment of sludge using filamentous fungus Mucor sp. GY-1.

Science.gov (United States)

Wang, Zhenyu; Zheng, Guanyu; Zhou, Lixiang

2015-09-01

Mechanisms responsible for the sludge dewaterability enhanced by filamentous fungi during fungal treatment of sludge were investigated in the present study. The filamentous fungus Mucor sp. GY-1, isolated from waste activated sludge, enhanced sludge dewaterability by 82.1% to achieve the lowest value of normalized sludge specific resistance to filtration (SRF), 8.18 × 10(10) m · L/kg · g-TSS. During the fungal treatment of sludge, 57.8% of slime extracellular polymeric substances (EPS) and 51.1% of polysaccharide in slime EPS were degraded, respectively, by Mucor sp. GY-1, contributing to the improvement of sludge dewaterability. Slime EPS is much more available for Mucor sp. GY-1 than either LB-EPS or TB-EPS that bound with microbial cells. In addition, filamentous fungus Mucor sp. GY-1 entrapped small sludge particles and inhibited the destruction of sludge flocs larger than 100 μm, thus enhancing sludge dewaterability, during fungal treatment of sludge using Mucor sp. GY-1. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fungal hyphae stimulate bacterial degradation of 2,6-dichlorobenzamide (BAM)

International Nuclear Information System (INIS)

Knudsen, Berith Elkær; Ellegaard-Jensen, Lea; Albers, Christian Nyrop; Rosendahl, Søren; Aamand, Jens

2013-01-01

Introduction of specific degrading microorganisms into polluted soil or aquifers is a promising remediation technology provided that the organisms survive and spread in the environment. We suggest that consortia, rather than single strains, may be better suited to overcome these challenges. Here we introduced a fungal–bacterial consortium consisting of Mortierella sp. LEJ702 and the 2,6-dichlorobenzamide (BAM)-degrading Aminobacter sp. MSH1 into small sand columns. A more rapid mineralisation of BAM was obtained by the consortium compared to MSH1 alone especially at lower moisture contents. Results from quantitative real-time polymerase chain reaction (qPCR) demonstrated better spreading of Aminobacter when Mortierella was present suggesting that fungal hyphae may stimulate bacterial dispersal. Extraction and analysis of BAM indicated that translocation of the compound was also affected by the fungal hyphae in the sand. This suggests that fungal–bacterial consortia are promising for successful bioremediation of pesticide contamination. -- Highlights: •Presence of fungi increased the rate of BAM mineralization by Aminobacter sp. MSH1. •Fungal–bacterial consortium enhanced BAM degradation at low moisture contents. •Mortierella hyphae facilitated transport of the BAM degrader Aminobacter sp. MSH1. -- This study brings new knowledge to the benefits of applying bacterial–fungal consortia for bioremediation

Biodegradation of dicyclopentadiene by a mini-consortium isolated from hydrocarbon contaminated soil

International Nuclear Information System (INIS)

Shen, Y.; Stehmeier, L.; Voordouw, G.

1997-01-01

Thirty-five bacterial species were isolated from soil contaminated by low molecular weight hydrocarbons (C5+). All species were identified by gene sequencing. The isolated genomic DNAs from these bacteria were spotted on a master filter in denatured form. They were then hybridized with total community DNAs isolated from soil exposed to dicyclopentadiene (DCPD) in order to determine the effect of DCPD on the soil microbial community by comparison with an untreated control group. Incubation of soil with DCPD enriched a Sphingomonas sp. while incubation with DCPD in the absence of soil gave enrichment of a Pseudomonas sp. These results indicate that identification of bacterial isolates with DCPD degrading potential is possible and that such organisms can be isolated from C5+ contaminated sites. However, the possibility of removing DCPD contamination in soil by bioremediation is not yet proven.10 refs., 2 tabs., 2 figs

Degradation of chitosan hydrogel dispersed in dilute carboxylic acids by solution plasma and evaluation of anticancer activity of degraded products

Science.gov (United States)

Chokradjaroen, Chayanaphat; Rujiravanit, Ratana; Theeramunkong, Sewan; Saito, Nagahiro

2018-01-01

Chitosan is a polysaccharide that has been extensively studied in the field of biomedicine, especially its water-soluble degraded products called chitooligosaccharides (COS). In this study, COS were produced by the degradation of chitosan hydrogel dispersed in a dilute solution (i.e., 1.55 mM) of various kinds of carboxylic acids using a non-thermal plasma technology called solution plasma (SP). The degradation rates of chitosan were influenced by the type of carboxylic acids, depending on the interaction between chitosan and each carboxylic acid. After SP treatment, the water-soluble degraded products containing COS could be easily separated from the water-insoluble residue of chitosan hydrogel by centrifugation. The production yields of the COS were mostly higher than 55%. Furthermore, the obtained COS products were evaluated for their inhibitory effect as well as their selectivity against human lung cancer cells (H460) and human lung normal cells (MRC-5).

Study of the electronic structure at the interface between fluorene-1-carboxylic acid molecules and Cu(110)

International Nuclear Information System (INIS)

Song Fei; Mao Hongying; Guan Dandan; Dou Weidong; Zhang Hanjie; Li Haiyang; He Pimo; Bao Shining; Hofmann, Philip

2009-01-01

The interface electronic properties of fluorene-1-carboxylic acid (FC-1) adsorbed on Cu(110) have been studied by ultraviolet photoemission spectroscopy (UPS) and first-principles calculations. Both the molecular orbitals and the Cu valence band are significantly modified upon adsorption. FC-1 is chemically bonded to Cu(110) through charge donation and back donation involving the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) of the molecule. An observed reduction of the work function can be attributed to the adsorption induced charge redistribution, and the positive interface dipole.

Isolation of Marine Bacillus sp. with Antagonistic and Organic-Substances-Degrading Activities and Its Potential Application as a Fish Probiotic

Directory of Open Access Journals (Sweden)

Shuxin Zhou

2018-06-01

Full Text Available We report on the isolation and characterization of an acid- and bile-tolerant bacterial strain, Bacillus sp. YB1701 with antibacterial and quorum-quenching activity. Strain YB1701 was isolated from coastal sediment samples and characterized by biochemical tests and 16S rRNA sequencing. In vitro study indicated that strain YB1701 can survive at pH 2.0 for up to 3 h and tolerate bile up to 2.0% concentration even after 12 h of exposure. Strain YB1701 showed antimicrobial activity against fish pathogens Aeromonas hydrophila and Vibrio parahemolyticus using an agar well diffusion assay. The trial test showed dietary supplementation of YB1701 significantly improved the resistance of Carassius auratus gibelio against A. hydrophila challenge. The safety assessment revealed that the isolate Bacillus sp. YB1701 was not cytotoxic to Carassius auratus gibelio or mice and did not exhibit hemolytic activity on rabbit blood agar plate. Disc-diffusion assays using a panel of antibiotics listed by the European Food Safety Authority (EFSA showed that YB1701 was susceptible to selected antibiotics. Under laboratory conditions, the degradation rate of organic waste (predominately fish excrement for 14 days by YB1701 was 79.69%. Results from the present study suggest that strain YB1701 is a potential probiotic strain and can be used in aquaculture for degrading organic waste and improving disease resistance of fish against bacterial infection. Further study is needed to assess the utility of strain YB1701 on a commercial scale.

High-density polyethylene (HDPE)-degrading potential bacteria from marine ecosystem of Gulf of Mannar, India.

Science.gov (United States)

Balasubramanian, V; Natarajan, K; Hemambika, B; Ramesh, N; Sumathi, C S; Kottaimuthu, R; Rajesh Kannan, V

2010-08-01

Assessment of high-density polyethylene (HDPE)-degrading bacteria isolated from plastic waste dumpsites of Gulf of Mannar. Rationally, 15 bacteria (GMB1-GMB15) were isolated by enrichment technique. GMB5 and GMB7 were selected for further studies based on their efficiency to degrade the HDPE and identified as Arthrobacter sp. and Pseudomonas sp., respectively. Assessed weight loss of HDPE after 30 days of incubation was nearly 12% for Arthrobacter sp. and 15% for Pseudomonas sp. The bacterial adhesion to hydrocarbon (BATH) assay showed that the cell surface hydrophobicity of Pseudomonas sp. was higher than Arthrobacter sp. Both fluorescein diacetate hydrolysis and protein content of the biofilm were used to test the viability and protein density of the biomass. Acute peak elevation was observed between 2 and 5 days of inoculation for both bacteria. Fourier transform infrared (FT-IR) spectrum showed that keto carbonyl bond index (KCBI), Ester carbonyl bond index (ECBI) and Vinyl bond index (VBI) were increased indicating changes in functional group(s) and/or side chain modification confirming the biodegradation. The results pose us to suggest that both Pseudomonas sp. and Arthrobacter sp. were proven efficient to degrade HDPE, albeit the former was more efficacious, yet the ability of latter cannot be neglected. Recent alarm on ecological threats to marine system is dumping plastic waste in the marine ecosystem and coastal arena by anthropogenic activity. In maintenance phase of the plastic-derived polyethylene waste, the microbial degradation plays a major role; the information accomplished in this work will be the initiating point for the degradation of polyethylene by indigenous bacterial population in the marine ecosystem and provides a novel eco-friendly solution in eco-management.

Isolation and Identification of Pyrene Mineralizing Mycobacterium spp. from Contaminated and Uncontaminated Sources

International Nuclear Information System (INIS)

Lease, C.W.M; Bentham, R.H; Gaskin, S.E; Juhasz, A.L

2011-01-01

Mycobacterium isolates obtained from PAH-contaminated and uncontaminated matrices were evaluated for their ability to degrade three-, four- and five-ring PAHs. PAH enrichment studies were prepared using pyrene and inocula obtained from manufacturing gas plant (MGP) soil, uncontaminated agricultural soil, and faeces from Macropus fuliginosus (Western Grey Kangaroo). Three pyrene-degrading microorganisms isolated from the corresponding enrichment cultures had broad substrate ranges, however, isolates could be differentiated based on surfactant, phenol, hydrocarbon and PAH utilisation. 16S rRNA analysis identified all three isolates as Mycobacterium sp. The Mycobacterium spp. could rapidly degrade phenanthrene and pyrene, however, no strain had the capacity to utilise fluorene or benzo[a]pyrene. When pyrene mineralisation experiments were performed, 70-79% of added 14 C was evolved as 14 CO 2 after 10 days. The present study demonstrates that PAH degrading microorganisms may be isolated from a diverse range of environmental matrices. The present study demonstrates that prior exposure to PAHs was not a prerequisite for PAH catabolic activity for two of these Mycobacterium isolates.

Utilizing a Spiro Core with Acridine- and Phenothiazine-Based New Hole Transporting Materials for Highly Efficient Green Phosphorescent Organic Light-Emitting Diodes

Directory of Open Access Journals (Sweden)

Ramanaskanda Braveenth

2018-03-01

Full Text Available Two new hole transporting materials, 2,7-bis(9,9-diphenylacridin-10(9H-yl-9,9′ spirobi[fluorene] (SP1 and 2,7-di(10H-phenothiazin-10-yl-9,9′-spirobi[fluorene] (SP2, were designed and synthesized by using the Buchwald–Hartwig coupling reaction with a high yield percentage of over 84%. Both of the materials exhibited high glass transition temperatures of over 150 °C. In order to understand the device performances, we have fabricated green phosphorescent organic light-emitting diodes (PhOLEDs with SP1 and SP2 as hole transporting materials. Both of the materials revealed improved device properties, in particular, the SP2-based device showed excellent power (34.47 lm/W and current (38.41 cd/A efficiencies when compare with the 4,4′-bis(N-phenyl-1-naphthylaminobiphenyl (NPB-based reference device (30.33 lm/W and 32.83 cd/A. The external quantum efficiency (EQE of SP2 was 13.43%, which was higher than SP1 (13.27% and the reference material (11.45% with a similar device structure. The SP2 hole transporting material provides an effective charge transporting path from anode to emission layer, which is explained by the device efficiencies.

Application of sewage sludge and intermittent aeration strategy to the bioremediation of DDT- and HCH-contaminated soil.

Science.gov (United States)

Liang, Qi; Lei, Mei; Chen, Tongbin; Yang, Jun; Wan, Xiaoming; Yang, Sucai

2014-08-01

Adding organic amendments to stimulate the biodegradation of pesticides is a subject of ongoing interest. The effect of sewage sludge on the bioremediation of dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH) contaminated soil was investigated in bench scale experiments, and intermittent aeration strategy was also used in this study to form an anaerobic-aerobic cycle. Bioremediation of DDT and HCH was enhanced with the addition of sewage sludge and the intermittent aeration. The removal rates of HCH and DDT were raised by 16.8%-80.8% in 10 days. Sewage sludge increased the organic carbon content from 6.2 to 218 g/kg, and it could also introduce efficient degradation microbes to soil, including Pseudomonas sp., Bacillus sp. and Sphingomonas sp. The unaerated phase enhanced the anaerobic dechlorination of DDT and HCH, and anaerobic removal rates of β-HCH, o,p'-DDT and p,p'-DDT accounted for more than 50% of the total removal rates, but the content of α-HCH declined more in the aerobic phase. Copyright © 2014. Published by Elsevier B.V.

Polyelectrolyte Complexes of a Cationic All Conjugated Fluorene Thiophene Diblock Copolymer with Aqueous DNA

DEFF Research Database (Denmark)

Knaapila, Matti; Costa, Telma; Garamus, Vasil M.

2015-01-01

TMAHT repeat units; x = 0.5 equals the nominal charge neutralization. PF2/6-P3TMAHT forms 20–40 nm sized particles with PF2/6 core and hydrated P3TMAHT exterior. The polymer particles form loose one-dimensional chains giving micrometer long branched chains (0.19 ≤ x ≤ 0.76) and subsequently randomly......We report on the structural and colorimetric effects of interaction of aqueous ∼0.06–1% poly[9,9-bis(2-ethylhexyl)fluorene]-b-poly[3-6-trimethylammoniumhexyl)thiophene] bromide (PF2/6-P3TMAHT) with double-stranded DNA to form PF2/6-P3TMAHT(DNA)x where x is the molar ratio of DNA base pairs to P3...

Destruction of acenaphthene, fluorene, anthracene and pyrene by a dc gliding arc plasma reactor.

Science.gov (United States)

Yu, Liang; Tu, Xin; Li, Xiaodong; Wang, Yu; Chi, Yong; Yan, Jianhua

2010-08-15

In this study, four kinds of PAHs (polycyclic aromatic hydrocarbons) i.e. acenaphthene, fluorene, anthracene and pyrene are used as targets for investigation of PAHs treatment process assisted by dc gliding arc discharge. The effects of carrier gas and external resistance on the PAHs decomposition process are discussed. The results indicate that the destruction rate can be achieved to the highest with the carrier gas of oxygen and the external resistance of 50 kOmega independent of type of PAHs. Furthermore, experimental results suggest that destruction energy efficiency of gliding arc plasma would be improved by treating higher concentration pollutants. Based on the analysis of experimental results, possible destruction mechanisms in different gas discharge are discussed. Copyright 2010 Elsevier B.V. All rights reserved.

Release and Degradation of Microencapsulated Spinosad and Emamectin Benzoate.

Science.gov (United States)

Huang, Bin Bin; Zhang, Shao Fei; Chen, Peng Hao; Wu, Gang

2017-09-07

The dynamics of release and degradation of the microencapsulation formulation containing spinosad (SP) and emamectin benzoate (EM) were evaluated in the present study. SP and EM were microencapsulated using biodegradable poly-lactic acid (PLA) as the wall material. Their release from and degradation within the prepared SP and EM microspheres (SP-EM-microspheres) were studied. It was found that the encapsulation significantly prolonged the insecticide release. The release could be further extended if the external aqueous phase was pre-saturated with the insecticides and the microspheres were additionally coated with gelatin. On the other hand, increasing the water content of the emulsion or the hydrophilic polycaprolactone (PCL) content in the PLA/PCL mixture accelerated the release. Due to the photolysis and hydrolysis of SP and EM by sunlight, the toxicity of the non-encapsulated insecticides in water declined continuously from 0 through the 9 th day (d), and dissipated in 13 d. In contrast, an aqueous suspension containing 5% SP-EM-microspheres maintained a mostly constant toxicity to Plutella xylostella for 17 d. The biodegradable SP-EM-microspheres showed significantly higher long-term toxicity to P. xylostella due to lower release, reduced photolysis and hydrolysis of the encapsulated insecticides, which were affected by the varied preparation conditions.

Biodegradation of Methyl tert-Butyl Ether by Co-Metabolism with a Pseudomonas sp. Strain

Directory of Open Access Journals (Sweden)

Shanshan Li

2016-09-01

Full Text Available Co-metabolic bioremediation is supposed to be an impressive and promising approach in the elimination technology of methyl tert-butyl ether (MTBE, which was found to be a common pollutant worldwide in the ground or underground water in recent years. In this paper, bacterial strain DZ13 (which can co-metabolically degrade MTBE was isolated and named as Pseudomonas sp. DZ13 based on the result of 16S rRNA gene sequencing analysis. Strain DZ13 could grow on n-alkanes (C5-C8, accompanied with the co-metabolic degradation of MTBE. Diverse n-alkanes with different carbon number showed a significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA. When Pseudomonas sp. DZ13 co-metabolically degraded MTBE with n-pentane as the growth substrate, a higher MTBE-degrading rate (Vmax = 38.1 nmol/min/mgprotein, Ks = 6.8 mmol/L and lower TBA-accumulation was observed. In the continuous degradation experiment, the removal efficiency of MTBE by Pseudomonas sp. Strain DZ13 did not show an obvious decrease after five times of continuous addition.

Modulated charge injection in p-type dye-sensitized solar cells using fluorene-based light absorbers.

Science.gov (United States)

Liu, Zonghao; Xiong, Dehua; Xu, Xiaobao; Arooj, Qudsia; Wang, Huan; Yin, Liyuan; Li, Wenhui; Wu, Huaizhi; Zhao, Zhixin; Chen, Wei; Wang, Mingkui; Wang, Feng; Cheng, Yi-Bing; He, Hongshan

2014-03-12

In this study, new pull-push arylamine-fluorene based organic dyes zzx-op1, zzx-op2, and zzx-op3 have been designed and synthesized for p-type dye-sensitized solar cells (p-DSCs). In zzx-op1, a di(p-carboxyphenyl)amine (DCPA) was used as an electron donor, a perylenemonoimide (PMID) as an electron acceptor, and a fluorene (FLU) unit with two aliphatic hexyl chains as a π-conjugated linker. In zzx-op2 and zzx-op3, a 3,4-ethylenedioxythiophene (EDOT) and a thiophene were inserted consecutively between PMID and FLU to tune the energy levels of the frontier molecular orbitals of the dyes. The structural modification broadened the spectral coverage from an onset of 700 nm for zzx-op1 to 750 nm for zzx-op3. The electron-rich EDOT and thiophene lifted up the HOMO (highest occupied molecular orbital) levels of zzx-op2 and zzx-op3, making their potential more negative than zzx-op1. When three dyes were employed in p-type DSCs with I(-)/I3(-) as a redox couple and NiO nanoparticles as hole materials, zzx-op1 exhibited impressive energy conversion efficiency of 0.184% with the open-circuit voltage (VOC) of 112 mV and the short-circuit current density (JSC) of 4.36 mA cm(-2) under AM 1.5G condition. Density functional theory calculations, transient photovoltage decay measurements, and electrochemical impedance spectroscopic studies revealed that zzx-op1 sensitized solar cell exhibited much higher charge injection efficiency (90.3%) than zzx-op2 (53.9%) and zzx-op3 (39.0%), indicating a trade-off between spectral broadening and electron injection driving force in p-type DSCs.

Theoretical investigations on fluorene-pyridines as electroactive sensor molecules

International Nuclear Information System (INIS)

Horner, S.; Romaner, L.; Zojer, E.; Kappaun, S.; Slugovc, C.; Kelterer, A.-M.

2006-01-01

Full text: Organic semiconducting oligomers and polymers are promising candidates for chemical sensing applications. In this work, sensor molecules comprising a sequence of para- and meta-linked fluorene- and pyridine- units are studied. Spectroscopic investigations show that upon protonation of the pyridine rings (i.e., when adding acids to the solutions), one observes a distinct red-shift of the absorption and emission maxima by approximately 0.5 eV. The fact that the polymers are highly emissive in both, the non protonated as well as protonated state makes them particularly interesting candidates for ratio metric sensors based on organic semiconductors. To rationalize the observed behaviour, we calculate the geometric and electronic structures of the relevant molecules at various stages of protonation using both semiempirical as well as density functional theory based methods. In general, we obtain good agreement between theory and experiment and excited state localization is found to play a crucial role in the sensing process. In practice, one can expect the interaction between the proton and the nitrogen of the pyridine unit to be modulated by interaction with the counter-ion as well as by screening through solvent molecules. These effects are accounted for in calculations on smaller model systems. (author)

Isolation and Characterization of Paracoccus sp. GSM2 Capable of Degrading Textile Azo Dye Reactive Violet 5

Directory of Open Access Journals (Sweden)

Mallikarjun C. Bheemaraddi

2014-01-01

Full Text Available A potential bacterial strain GSM2, capable of degrading an azo dye Reactive Violet 5 as a sole source of carbon, was isolated from textile mill effluent from Solapur, India. The 16S rDNA sequence and phenotypic characteristics indicated an isolated organism as Paracoccus sp. GSM2. This strain exhibited complete decolorization of Reactive Violet 5 (100 mg/L within 16 h, while maximally it could decolorize 800 mg/L of dye within 38 h with 73% decolorization under static condition. For color removal, the most suitable pH and temperature were pH 6.0–9.0 and 25–40°C, respectively. The isolate was able to decolorize more than 70% of five structurally different azo dyes within 38 h. The isolate is salt tolerant as it can bring out more than 90% decolorization up to a salt concentration of 2% (w/v. UV-Visible absorption spectra before and after decolorization suggested that decolorization was due to biodegradation and was further confirmed by FT-IR spectroscopy. Overall results indicate the effectiveness of the strain GSM2 explored for the treatment of textile industry effluents containing various azo dyes. To our knowledge, this could be the first report on biodegradation of Reactive Violet 5 by Paracoccus sp. GSM2.

Studies of action of heavy metals on caffeine degradation by ...

African Journals Online (AJOL)

Caffeine is an important naturally occurring compound that can be degraded by bacteria. Excessive caffeine consumption is known to have some adverse problems. Previously, Leifsonia sp. strain SIU capable of degrading caffeine was isolated from agricultural soil. The bacterium was tested for its ability to degrade caffeine ...

Ternary thiophene-X-thiophene semiconductor building blocks (X = fluorene, carbazole, phenothiazine): Modulating electronic properties and electropolymerization ability by tuning the X core

Energy Technology Data Exchange (ETDEWEB)

Tacca, Alessandra, E-mail: alessandra.tacca@eni.com [Centro Ricerche per le Energie non Convenzionali, Istituto ENI Donegani, ENI S.p.A., Via G. Fauser 4, 28100 Novara (Italy); Po, Riccardo; Caldararo, Maria; Chiaberge, Stefano; Gila, Liliana; Longo, Luca [Centro Ricerche per le Energie non Convenzionali, Istituto ENI Donegani, ENI S.p.A., Via G. Fauser 4, 28100 Novara (Italy); Mussini, Patrizia Romana [Dipartimento di Chimica Fisica ed Elettrochimica, Universita degli Studi di Milano, Via Golgi 19, 20133 Milano (Italy); Pellegrino, Andrea; Perin, Nicola; Salvalaggio, Mario; Savoini, Alberto; Spera, Silvia [Centro Ricerche per le Energie non Convenzionali, Istituto ENI Donegani, ENI S.p.A., Via G. Fauser 4, 28100 Novara (Italy)

2011-07-30

Highlights: > Effect of aromatic core on electronic properties in thiophene-X-thiophene trimers. > The lower the electron richness of X core, the deeper the HOMO level. > Different thiophene positions on X lead to kinked structure with lower conjugation. > The fluorene structure exhibits the lowest Stokes shift and the highest quantum yield. > The corresponding polymers obtained through three routes were studied. - Abstract: To achieve rationalization criteria for target-oriented molecular design of Th-X-Th (Th = thiophene) semiconductor building blocks, we have carried out an extensive investigation on the effects of the X core (X = fluorene, carbazole or phenothiazine) on the electronic properties and polymerization ability of Th-X-Th monomers and on the electronic and structural properties of the corresponding periodic conducting polymers -(Th-X-Th){sub n}-, obtained by electropolymerization and, for comparison's sake, by FeCl{sub 3}-catalyzed polymerization and/or Suzuki coupling. The effects of molecule bending and of solubilising bulky alkyl substituents have also been considered. The systematic, exhaustive template sequence combined with a rigorous, multitechnique investigation protocol affords a unique data library and a complete set of reliable interpretative/predictive guidelines.

Interactions between Pteris vittata L. genotypes and a polycyclic aromatic hydrocarbon (PAH)-degrading bacterium (Alcaligenes sp.) in arsenic uptake and PAH-dissipation.

Science.gov (United States)

Sun, Lu; Zhu, Ganghui; Liao, Xiaoyong; Yan, Xiulan

2017-11-01

The effects of two Pteris vittata L. accessions and a polycyclic aromatic hydrocarbon (PAH)-degrading bacterium (Alcaligenes sp.) on arsenic (As) uptake and phenanthrene dissipation were studied. The Alcaligenes sp. survived in the rhizosphere and improved soil As bioavailability with co-exposure. However, bacterial inoculation altered Pteris vittata L. stress tolerance, and substantially affected the As distribution in the rhizosphere of the two P. vittata accessions. Bacterial inoculation was beneficial to protect the Guangxi accession against the toxic effects, and significantly increased plant As and phenanthrene removal ratios by 27.8% and 2.89%, respectively. In contrast, As removal was reduced by 29.8% in the Hunan accession, when compared with corresponding non-inoculated treatments. We conclude that plant genotype selection is critically important for successful microorganism-assisted phytoremediation of soil co-contaminated with As and PAHs, and appropriate genotype selection may enhance remediation efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

Taxonomic characterization of the cellulose-degrading bacterium NCIB 10462

Energy Technology Data Exchange (ETDEWEB)

Dees, C.; Ringleberg, D.; Scott, T.C. [Oak Ridge National Lab., TN (United States); Phelps, T. [Univ. of Tennessee, Knoxville, TN (United States)

1994-06-01

The gram negative cellulase-producing bacterium NCIB 10462 has been previously named Pseudomonas fluorescens subsp. or var. cellulosa. Since there is renewed interest in cellulose-degrading bacteria for use in bioconversion of cellulose to chemical feed stocks and fuels, we re-examined the characteristics of this microorganism to determine its proper taxonomic characterization and to further define it`s true metabolic potential. Metabolic and physical characterization of NCIB 10462 revealed that this was an alkalophilic, non-fermentative, gram negative, oxidase positive, motile, cellulose-degrading bacterium. The aerobic substrate utilization profile of this bacterium was found to have few characteristics consistent with a classification of P. fluorescens with a very low probability match with the genus Sphingomonas. Total lipid analysis did not reveal that any sphingolipid bases are produced by this bacterium. NCIB 10462 was found to grow best aerobically but also grows well in complex media under reducing conditions. NCIB 10462 grew slowly under full anaerobic conditions on complex media but growth on cellulosic media was found only under aerobic conditions. Total fatty acid analysis (MIDI) of NCIB 10462 failed to group this bacterium with a known pseudomonas species. However, fatty acid analysis of the bacteria when grown at temperatures below 37{degrees}C suggest that the organism is a pseudomonad. Since a predominant characteristic of this bacterium is it`s ability to degrade cellulose, we suggest it be called Pseudomonas cellulosa.

Heterologous expression of mlrA in a photoautotrophic host - Engineering cyanobacteria to degrade microcystins.

Science.gov (United States)

Dexter, Jason; Dziga, Dariusz; Lv, Jing; Zhu, Junqi; Strzalka, Wojciech; Maksylewicz, Anna; Maroszek, Magdalena; Marek, Sylwia; Fu, Pengcheng

2018-06-01

In this report, we establish proof-of-principle demonstrating for the first time genetic engineering of a photoautotrophic microorganism for bioremediation of naturally occurring cyanotoxins. In model cyanobacterium Synechocystis sp. PCC 6803 we have heterologously expressed Sphingopyxis sp. USTB-05 microcystinase (MlrA) bearing a 23 amino acid N-terminus secretion peptide from native Synechocystis sp. PCC 6803 PilA (sll1694). The resultant whole cell biocatalyst displayed about 3 times higher activity against microcystin-LR compared to a native MlrA host (Sphingomonas sp. ACM 3962), normalized for optical density. In addition, MlrA activity was found to be almost entirely located in the cyanobacterial cytosolic fraction, despite the presence of the secretion tag, with crude cellular extracts showing MlrA activity comparable to extracts from MlrA expressing E. coli. Furthermore, despite approximately 9.4-fold higher initial MlrA activity of a whole cell E. coli biocatalyst, utilization of a photoautotrophic chassis resulted in prolonged stability of MlrA activity when cultured under semi-natural conditions (using lake water), with the heterologous MlrA biocatalytic activity of the E. coli culture disappearing after 4 days, while the cyanobacterial host displayed activity (3% of initial activity) after 9 days. In addition, the cyanobacterial cell density was maintained over the duration of this experiment while the cell density of the E. coli culture rapidly declined. Lastly, failure to establish a stable cyanobacterial isolate expressing native MlrA (without the N-terminus tag) via the strong cpcB560 promoter draws attention to the use of peptide tags to positively modulate expression of potentially toxic proteins. Copyright © 2018 Elsevier Ltd. All rights reserved.

Exciplex elimination in an organic light-emitting diode based on a fluorene derivative by inserting 4,4'-N,N'-dicarbazole-biphenylinto donor/acceptor interface

International Nuclear Information System (INIS)

Wei, Zhang; Jun-Sheng, Yu; Jiang, Huang; Ya-Dong, Jiang; Qing, Zhang; Kang-Li, Cao

2010-01-01

Organic light-emitting diodes (OLEDs) composed of a novel fluorene derivative of 2,3-bis(9,9-dihexyl-9H-fluoren-2-yl)-6,7-difluoroquinoxaline (F2Py) were fabricated, and exciplex emission was observed in the device. To depress the exciplex in an OLED for pure colour light emission, 4, 4'-N,N'-dicarbazole-biphenyl (CBP) was inserted as a separator at the donor/acceptor interface. It was found that the device without the CBP layer emitted a green light peaking at 542 nm from the exciplex and a shoulder peak about 430 nm from F2Py. In contrast, the OLED with CBP layer emitted only a blue light peak at about 432 nm from F2Py. Device efficiencies were calculated by a simulative mode in an injection controlled type mechanism, and the results showed that exciplexes yield much lower quantum efficiency than excitons. The device with CBP has a higher power efficiency as no exciplex was present. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Biodegradation of resorcinol byPseudomonas sp.

Institute of Scientific and Technical Information of China (English)

Nader Hajizadeh; Najibeh Shirzad; Ali Farzi; Mojtaba Salouti; Azra Momeni

2016-01-01

ABSTRACT Objective:To investigate the ability ofPseudomonas sp. isolated from East Azarbaijan, Iran in bioremediation of resorcinol. Methods: Resorcinol biodegradation was evaluated using spectrophotometry and confirmed by gas chromatography-mass spectroscopy. Results:This isolate was able to remove up to 37.12% of resorcinol from contaminated water. Reusability experiments had confirmed the biodegradation process which produced seven intermediate compounds. These intermediates were characterized by gas chromatography-mass spectroscopy technique. The products of resorcinol biodegradation were apparently 1, 4-cyclohexadiene, nonadecene, 2-heptadecanone, 1-isopropyl-2-methoxy-4-methylbenzene, hexadecanoic acid, 9-octadecenoic acid, phenol and 5-methyl-2-(1-methylethyl). Conclusions: The findings revealed thatPseudomonas sp. is able to degrade resorcinol. Because of being an indigenous organism, this isolate is more compatible with the climate of the northwest region of Iran and possibly will be used for degradation of other similar aromatic compounds.

Glyphosate catabolism by Pseudomonas sp

International Nuclear Information System (INIS)

Shinabarger, D.L.

1986-01-01

The pathway for the degradation of glyphosate (N-phosphonomethylglycine) by Pseudomonas sp. PG2982 has been determined using metabolic radiolabeling experiments. Radiorespirometry experiments utilizing [3- 14 C] glyphosate revealed that approximately 50-59% of the C3 carbon was oxidized to CO 2 . Fractionation of stationary phase cells labeled with [3- 14 C]glyphosate revealed that from 45-47% of the assimilated C3 carbon is distributed to proteins and that amino acids methionine and serine are highly labeled. The nucleic acid bases adenine and guanine received 90% of the C3 label that was incorporated into nucleic acids, and the only pyrimidine base labeled was thymine. Pulse labeling of PG2982 cells with [3- 14 C]glyphosate revealed that [3- 14 C]sarcosine is an intermediate in glyphosate degradation. Examination of crude extracts prepared from PG2982 cells revealed the presence of an enzyme that oxidizes sarcosine to glycine and formaldehyde. These results indicate that the first step in glyphosate degradation by PG2982 is cleavage of the carbon-phosphorus bond, resulting in the release of sarcosine and a phosphate group. The phosphate group is utilized as a source of phosphorus, and the sarcosine is degraded to glycine and formaldehyde. Phosphonate utilization by Pseudomonas sp. PG2982 was investigated. Each of the ten phosphonates tested were utilized as a sole source of phosphorus by PG2982. Representative compounds tested included alkylphosphonates, 1-amino-substituted alkylphosphonates, amino-terminal phosphonates, and an arylphosphonate. PG2982 cultures degraded phenylphosphonate to benzene and produced methane from methylphosphonate. The data indicate that PG2982 is capable of cleaving the carbon-phosphorus bond of several structurally different phosphonates

Bacterial degradation of styrene in waste gases using a peat filter

Energy Technology Data Exchange (ETDEWEB)

Arnold, M.; Reittu, A. [Kuopio Univ. (Finland). Dept. of Environmental Sciences; Wright, A. von; Suihko, M.L. [VTT Biotechnology and Food Research (Finland); Martikainen, P.J. [Kuopio Univ. (Finland). Dept. of Environmental Sciences]|[National Public Health Inst., Lab. of Environmental Microbiology, Kuopio (Finland)

1997-12-31

A biofiltration process was developed for styrene-containing off-gases using peat as filter material. The average styrene reduction ratio after 190 days of operation was 70% (max. 98%) and the mean styrene elimination capacity was 12 g m{sup -3} h{sup -1} (max. 30 g m{sup -3} h{sup -1}). Efficient styrene degradation required addition of nutrients to the peat, adjustment of the pH to a neutral level and efficient control of the humidity. Maintenance of the water balance was easier in a down-flow than in an up-flow process, the former consequently resulting in much better filtration efficiency. The optimum operation temperature was around 23 C, but the styrene removal was still satisfactory at 12 C. Seven different bacterial isolates belonging to the genera Tsukamurella, Pseudomonas, Sphingomonas, Xanthomonas and an unidentified genus in the {gamma} group of the Proteobacteria isolated from the microflora of active peat filter material were capable of styrene degradation. The isolates differed in their capacity to decompose styrene to carbon dioxide and assimilate it to biomass. No toxic intermediate degradation products of styrene were detected in the filter outlet gas or in growing cultures of isolated bacteria. The use of these isolates in industrial biofilters is beneficial at low styrene concentrations and is safe from both the environmental and public health points of view. (orig.)

Bacterial degradation of styrene in waste gases using a peat filter.

Science.gov (United States)

Arnold, M; Reittu, A; von Wright, A; Martikainen, P J; Suihko, M L

1997-12-01

A biofiltration process was developed for styrene-containing off-gases using peat as filter material. The average styrene reduction ratio after 190 days of operation was 70% (max. 98%) and the mean styrene elimination capacity was 12 g m-3 h-1 (max. 30 g m-3 h-1). Efficient styrene degradation required addition of nutrients to the peat, adjustment of the pH to a neutral level and efficient control of the humidity. Maintenance of the water balance was easier in a down-flow than in an up-flow process, the former consequently resulting in much better filtration efficiency. The optimum operation temperature was around 23 degrees C, but the styrene removal was still satisfactory at 12 degrees C. Seven different bacterial isolates belonging to the genera Tsukamurella, Pseudomonas, Sphingomonas, Xanthomonas and an unidentified genus in the gamma group of the Proteobacteria isolated from the microflora of active peat filter material were capable of styrene degradation. The isolates differed in their capacity to decompose styrene to carbon dioxide and assimilate it to biomass. No toxic intermediate degradation products of styrene were detected in the filter outlet gas or in growing cultures of isolated bacteria. The use of these isolates in industrial biofilters is beneficial at low styrene concentrations and is safe from both the environmental and public health points of view.

Toxicity assessment of pesticide triclosan by aquatic organisms and degradation studies.

Science.gov (United States)

Taştan, Burcu Ertit; Tekinay, Turgay; Çelik, Hatice Sena; Özdemir, Caner; Cakir, Dilara Nur

2017-12-01

Triclosan is considered as an important contaminant and is widely used in personal care products as an antimicrobial agent. This study demonstrates the biodegradation of triclosan by two freshwater microalgae and the acute toxicity of triclosan and 2,4-dichlorophenol. The effects of culture media and light on biodegradation of triclosan and the changing morphology of microalgae were systematically studied. Geitlerinema sp. and Chlorella sp. degraded 82.10% and 92.83% of 3.99 mg/L of triclosan at 10 days, respectively. The microalgal growth inhibition assay confirmed absence of toxic effects of triclosan on Chlorella sp., even at higher concentration (50 mg/L) after 72 h exposure. HPLC analysis showed that 2,4-dichlorophenol was produced as degradation product of triclosan by Geitlerinema sp. and Chlorella sp. This study proved to be beneficial to understand biodegradation and acute toxicity of triclosan by microalgae in order to provide aquatic environmental protection. Copyright © 2017 Elsevier Inc. All rights reserved.

Bacteria capable of degrading anthracene, phenanthrene, and fluoranthene as revealed by DNA based stable-isotope probing in a forest soil

Energy Technology Data Exchange (ETDEWEB)

Song, Mengke [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Jiang, Longfei [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Zhang, Dayi [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Luo, Chunling, E-mail: clluo@gig.ac.cn [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Wang, Yan [Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Yu, Zhiqiang [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Yin, Hua [College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Zhang, Gan [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

2016-05-05

Highlights: • Investigate PAHs degraders in forest carbon-rich soils via DNA-SIP. • Rhodanobacter is identified to metabolite anthracene for the first time. • The first fluoranthene degrader belongs to Acidobacteria. • Different functions of PAHs degraders in forest soils from contaminated soils. - Abstract: Information on microorganisms possessing the ability to metabolize different polycyclic aromatic hydrocarbons (PAHs) in complex environments helps in understanding PAHs behavior in natural environment and developing bioremediation strategies. In the present study, stable-isotope probing (SIP) was applied to investigate degraders of PAHs in a forest soil with the addition of individually {sup 13}C-labeled phenanthrene, anthracene, and fluoranthene. Three distinct phylotypes were identified as the active phenanthrene-, anthracene- and fluoranthene-degrading bacteria. The putative phenanthrene degraders were classified as belonging to the genus Sphingomona. For anthracene, bacteria of the genus Rhodanobacter were the putative degraders, and in the microcosm amended with fluoranthene, the putative degraders were identified as belonging to the phylum Acidobacteria. Our results from DNA-SIP are the first to directly link Rhodanobacter- and Acidobacteria-related bacteria with anthracene and fluoranthene degradation, respectively. The results also illustrate the specificity and diversity of three- and four-ring PAHs degraders in forest soil, contributes to our understanding on natural PAHs biodegradation processes, and also proves the feasibility and practicality of DNA-based SIP for linking functions with identity especially uncultured microorganisms in complex microbial biota.

Diesel degradation and biosurfactant production by Gram-positive ...

African Journals Online (AJOL)

The ability of Gram-positive bacteria to degrade diesel increased in a comparable trend as its biosurfactant production increased. The E24 index was highest at 87.6% for isolate D9. Isolates D2, D9 and D10, were identified as Paenibacillus sp. whilst isolate DJLB was found to belong to Stenotrophomonas sp. This study ...

New strains of oil-degrading microorganisms for treating contaminated soils and wastes

Science.gov (United States)

Muratova, A. Yu; Panchenko, L. V.; Semina, D. V.; Golubev, S. N.; Turkovskaya, O. V.

2018-01-01

Two new strains Achromobacter marplatensis101n and Acinetobacter sp. S-33, capable of degrading 49 and 46% of oil within 7 days were isolated, identified, and characterized. The application of A. marplatensis 101n in combination with ammonium nitrate (100 mg·kg-1) for 30 days of cultivation resulted in the degradation of 49% of the initial total petroleum hydrocarbon content (274 g·kg-1) in the original highly acid (pH 4.9) oil-contaminated waste. Up to 30% of oil sludge added to a liquid mineral medium at a concentration of 15% was degraded after 10 days of cultivation of A. marplatensis 101n. Application of yellow alfalfa (Medicago falcata L.) plants with Acinetobacter sp. S-33 for bioremediation of oil-sludge-contaminated soil improved the quality of cleanup in comparison with the bacterium- or plant-only treatment. Inoculation of Acinetobacter sp. S-33 increased the growth of both roots and shoots by more than 40%, and positively influenced the soil microflora. We conclude that the new oil-degrading strains, Acinetobacter sp. S-33 and A. marplatensis 101n, can serve as the basis for new bioremediation agents for the treatment of oil contaminated soils and waste.

Evaluation of toughness degradation by small punch (SP) tests for neutron irradiated structural steels

International Nuclear Information System (INIS)

Misawa, Toshihei; Hamaguchi, Yoshikazu; Kimura, Akihiko; Eto, Motokuni; Suzuki, Masahide; Nakajima, Nobuya.

1992-01-01

The small punch (SP) test as one of the useful small specimen testing technique (SSTT) has been developed to evaluate the fracture toughness, ductile-brittle transition temperature (DBTT) and tensile properties for neutron irradiated structural materials. The SP tests using the miniaturized specimens of φ3 mm TEM disk and 10 mm 2 coupon were performed for six kinds of ferritic steels of F-82, F-82H, HT-9, JFMS, 2.25-1Mo and SQV2A. It was shown that the temperature dependence of SP fracture energies with scatter in miniaturized testing can give reliable information on the DBTT by use of the statistical analysis based on the Weibull distribution. A good correlation between the DBTT of the SP tests and that of the standard CVN test has been obtained for the various nuclear ferritic steels. The SP test was performed for cryogenic austenitic steels as a way of evaluating elastic-plastic fracture toughness, J IC , on the basis of a universal empirical relationship between J IC and SP equivalent fracture strain, ε-bar qf . The SP testing using the neutron irradiated specimens of 2.25Cr-1Mo, F-82, F-82H and HT-9 steels was successfully applied and presented the neutron radiation induced changes on the DBTT, fracture toughness and tensile properties. (author)

Enhanced photocatalytic activity induced by sp 3 to sp 2 transition of carbon dopants in BiOCl crystals

KAUST Repository

Sun, Jianguo

2017-09-19

The insufficient light absorption and low quantum efficiency limit the photocatalytic performance of wide bandgap semiconductors. Here, we report a facile strategy to engineer the surface disordered defects of BiOCl nanosheets via carbon doping. The surface defects boost the light absorption and also the quantum yields, as the doped carbon atoms exhibit a transition from sp3 to sp2 hybridization at elevated temperature, corresponding to a change of assembly state from 3D cluster to 2D graphite-like structure. This transition results in an effective charge separation and thus one order of enhancement in photocatalytic activity toward phenol degradation under visible light. The current study opens an avenue to introduce sp3 to sp2 transition of carbon dopants for simultaneous increment of light absorption and quantum efficiency for application in photocatalysis and energy conversion.

Treatment of petroleum industry oil sludge by Rhodotorula sp

Energy Technology Data Exchange (ETDEWEB)

Shailubhai, K.; Rao, N.N.; Modi, V.V.

1984-06-01

A Rhodotorula sp., isolated from soil, which showed a versatile capacity to degrade various aromatic and aliphatic hydrocarbons, was used to treat oil sludge. As a result of treatment, there was significant decrease in BOD, COD and contents of various petroleum fractions. The susceptibility to degradation was in the following order: saturate fraction >aromatic fraction> asphaltic fraction.

Combination of upflow anaerobic sludge blanket (UASB) and membrane bioreactor (MBR) for berberine reduction from wastewater and the effects of berberine on bacterial community dynamics.

Science.gov (United States)

Qiu, Guanglei; Song, Yonghui; Zeng, Ping; Duan, Liang; Xiao, Shuhu

2013-02-15

Berberine is a broad-spectrum antibiotic extensively used in personal medication. The production of berberine results in the generation of wastewater containing concentrated residual berberine. However, few related studies up to date focus on berberine removal from wastewaters. In this study, a lab-scale upflow anaerobic sludge blanket (UASB)-membrane bioreactor (MBR) process was developed for berberine removal from synthetic wastewater. The performance of the UASB-MBR system on berberine, COD and NH(4)(+)--N removal was investigated at different berberine loadings. And the effects of berberine on bacterial communities were evaluated using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Results showed that, as the increase of berberine loadings, UASB performance was affected remarkably, whereas, efficient and stable performance of MBR ensured the overall removal rates of berberine, COD and NH(4)(+)--N consistently reached up to 99%, 98% and 98%, respectively. Significant shifts of bacterial community structures were detected in both UASB and MBR, especially in the initial operations. Along with the increase of berberine loadings, high antibiotic resisting species and some functional species, i.e. Acinetobacter sp., Clostridium sp., Propionibacterium sp., and Sphingomonas sp. in UASB, as well as Sphingomonas sp., Methylocystis sp., Hydrogenophaga sp. and Flavobacterium sp. in MBR were enriched in succession. Copyright © 2013 Elsevier B.V. All rights reserved.

Paracetamol - toxicity and microbial utilization. Pseudomonas moorei KB4 as a case study for exploring degradation pathway.

Science.gov (United States)

Żur, Joanna; Wojcieszyńska, Danuta; Hupert-Kocurek, Katarzyna; Marchlewicz, Ariel; Guzik, Urszula

2018-09-01

Paracetamol, a widely used analgesic and antipyretic drug, is currently one of the most emerging pollutants worldwide. Besides its wide prevalence in the literature only several bacterial strains able to degrade this compound have been described. In this study, we isolated six new bacterial strains able to remove paracetamol. The isolated strains were identified as the members of Pseudomonas, Bacillus, Acinetobacter and Sphingomonas genera and characterized phenotypically and biochemically using standard methods. From the isolated strains, Pseudomonas moorei KB4 was able to utilize 50 mg L -1 of paracetamol. As the main degradation products, p-aminophenol and hydroquinone were identified. Based on the measurements of specific activity of acyl amidohydrolase, deaminase and hydroquinone 1,2-dioxygenase and the results of liquid chromatography analyses, we proposed a mechanism of paracetamol degradation by KB4 strain under co-metabolic conditions with glucose. Additionally, toxicity bioassays and the influence of various environmental factors, including pH, temperature, heavy metals at no-observed-effective-concentrations, and the presence of aromatic compounds on the efficiency and mechanism of paracetamol degradation by KB4 strain were determined. This comprehensive study about paracetamol biodegradation will be helpful in designing a treatment systems of wastewaters contaminated with paracetamol. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sequential Isolation of Saturated, Aromatic, Resinic and Asphaltic Fractions Degrading Bacteria from Oil Contaminated Soil in South Sumatera

Directory of Open Access Journals (Sweden)

Pingkan Aditiawati

2012-04-01

Full Text Available Sequential isolation has been conducted to obtain isolates of saturated, aromatic, resin, and asphaltene fractions degrading bacteria from oil contaminated sites. Five soil samples were collected from South Sumatera. These were analyzed using soil extract medium enriched with oil recovery or Remaining-Oil recovery Degradated (ROD as sole carbon and energy sources according to the isolation stage. ROD at the end of every isolation stage analyzed oil fractions by use of the SARA analysis method. Six isolates of bacteria have been selected, one isolate was fraction saturates degrading bacteria that are Mycobacterium sp. T1H2D4-7 at degradation rate 0.0199 mgs/h with density 8.4x106 cfu/g from stage I. The isolate T2H1D2-4, identified as Pseudomonas sp. was fraction aromatics degrading bacteria at accelerate 0.0141 mgs/h with density 5.1x106 cfu/g are obtained at stage II. Two isolates namely Micrococcus sp. T3H2D4-2 and Pseudomonas sp. T1H1D5-5 were fraction resins degrading bacteria by accelerate 0.0088 mgs/h at density 5.6x106 cfu/g and 0.0089 mgs/h at density 5.7x106 cfu/g are obtained at stage III. Isolation of stage IV has been obtained two isolates Pseudomonas sp. T4H1D3-1and Pseudomonas sp. T4H3D5-4 were fraction asphaltenes degrading bacteria by accelerate 0.0057 mgs/h at density 5.6x106 cfu/g and accelerate 0.0058 mgs/h at density 5.7x106 cfu/g.

Whole Genome Sequence Analysis of an Alachlor and Endosulfan Degrading Micrococcus sp. strain 2385 Isolated from Ochlockonee River, Florida.

Science.gov (United States)

Pathak, Ashish; Chauhan, Ashvini; Ewida, Ayman Y I; Stothard, Paul

2016-01-01

We recently isolated Micrococcus sp. strain 2385 from Ochlockonee River, Florida and demonstrated potent biodegradative activity against two commonly used pesticides- alachlor [(2-chloro-2`,6`-diethylphenyl-N (methoxymethyl)acetanilide)] and endosulfan [(6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9methano-2,3,4-benzo(e)di-oxathiepin-3-oxide], respectively. To further identify the repertoire of metabolic functions possessed by strain 2385, a draft genome sequence was obtained, assembled, annotated and analyzed. The genome sequence of Micrococcus sp. strain 2385 consisted of 1,460,461,440 bases which assembled into 175 contigs with an N50 contig length of 50,109 bases and a coverage of 600x. The genome size of this strain was estimated at 2,431,226 base pairs with a G+C content of 72.8 and a total number of 2,268 putative genes. RAST annotated a total of 340 subsystems in the genome of strain 2385 along with the presence of 2,177 coding sequences. A genome wide survey indicated that that strain 2385 harbors a plethora of genes to degrade other pollutants including caprolactam, PAHs (such as naphthalene), styrene, toluene and several chloroaromatic compounds.

Effect of pH and inoculum size on pentachlorophenol degradation ...

African Journals Online (AJOL)

The success of this depends on finding strains able to degrade PCP in a changeable environment. The aim of this work was to study the influence of pH of the medium and the effect of inoculum size on pentachlorophenol degradation by Pseudomonas sp. A study of PCP degradation kinetics was performed to assess such ...

Impact of the hydrogen partial pressure on lactate degradation in a coculture of Desulfovibrio sp. G11 and Methanobrevibacter arboriphilus DH1.

Science.gov (United States)

Junicke, H; Feldman, H; van Loosdrecht, M C M; Kleerebezem, R

2015-04-01

In this study, the impact of the hydrogen partial pressure on lactate degradation was investigated in a coculture of Desulfovibrio sp. G11 and Methanobrevibacter arboriphilus DH1. To impose a change of the hydrogen partial pressure, formate was added to the reactor. Hydrogen results from the bioconversion of formate besides lactate in the liquid phase. In the presence of a hydrogen-consuming methanogen, this approach allows for a better estimation of low dissolved hydrogen concentrations than under conditions where hydrogen is supplied externally from the gas phase, resulting in a more accurate determination of kinetic parameters. A change of the hydrogen partial pressure from 1,200 to 250 ppm resulted in a threefold increase of the biomass-specific lactate consumption rate. The 50 % inhibition constant of hydrogen on lactate degradation was determined as 0.692 ± 0.064 μM dissolved hydrogen (831 ± 77 ppm hydrogen in the gas phase). Moreover, for the first time, the maximum biomass-specific lactate consumption rate of Desulfovibrio sp. G11 (0.083 ± 0.006 mol-Lac/mol-XG11/h) and the affinity constant for hydrogen uptake of Methanobrevibacter arboriphilus DH1 (0.601 ± 0.022 μM dissolved hydrogen) were determined. Contrary to the widely established view that the biomass-specific growth rate of a methanogenic coculture is determined by the hydrogen-utilizing partner; here, it was found that the hydrogen-producing bacterium determined the biomass-specific growth rate of the coculture grown on lactate and formate.

Mouse Mammary Tumor Virus Signal Peptide Uses a Novel p97-Dependent and Derlin-Independent Retrotranslocation Mechanism To Escape Proteasomal Degradation

Directory of Open Access Journals (Sweden)

Hyewon Byun

2017-03-01

Full Text Available Multiple pathogens, including viruses and bacteria, manipulate endoplasmic reticulum-associated degradation (ERAD to avoid the host immune response and promote their replication. The betaretrovirus mouse mammary tumor virus (MMTV encodes Rem, which is a precursor protein that is cleaved into a 98-amino-acid signal peptide (SP and a C-terminal protein (Rem-CT. SP uses retrotranslocation for ER membrane extraction and yet avoids ERAD by an unknown mechanism to enter the nucleus and function as a Rev-like protein. To determine how SP escapes ERAD, we used a ubiquitin-activated interaction trap (UBAIT screen to trap and identify transient protein interactions with SP, including the ERAD-associated p97 ATPase, but not E3 ligases or Derlin proteins linked to retrotranslocation, polyubiquitylation, and proteasomal degradation of extracted proteins. A dominant negative p97 ATPase inhibited both Rem and SP function. Immunoprecipitation experiments indicated that Rem, but not SP, is polyubiquitylated. Using both yeast and mammalian expression systems, linkage of a ubiquitin-like domain (UbL to SP or Rem induced degradation by the proteasome, whereas SP was stable in the absence of the UbL. ERAD-associated Derlin proteins were not required for SP activity. Together, these results suggested that Rem uses a novel p97-dependent, Derlin-independent retrotranslocation mechanism distinct from other pathogens to avoid SP ubiquitylation and proteasomal degradation.

Decolorization pathways of anthraquinone dye Disperse Blue 2BLN by Aspergillus sp. XJ-2 CGMCC12963.

Science.gov (United States)

Pan, Huiran; Xu, Xiaolin; Wen, Zhu; Kang, Yanshun; Wang, Xinhao; Ren, Youshan; Huang, Danqi

2017-09-03

Anthraquinone dye represents an important group of recalcitrant pollutants in dye wastewater. Aspergillus sp XJ-2 CGMCC12963 showed broad-spectrum decolorization ability, which could efficiently decolorize and degrade various anthraquinone dyes (50 mg L -1 ) under microaerophilic condition. And the decolorization rate of 93.3% was achieved at 120 h with Disperse Blue 2BLN (the target dye). Intermediates of degradation were detected by FTIR and GC-MS, which revealed the cleavage of anthraquinone chromophoric group and partial mineralization of target dye. In addition, extracellular manganese peroxidase showed the most closely related to the increasing of decolorization rate and biomass among intracellular and extracellular ligninolytic enzymes. Given these results, 2 possible degraded pathways of target dye by Aspergillus sp XJ-2 CGMCC12963 were proposed first in this work. The degradation of Disperse Blue 2BLN and broad spectrum decolorization ability provided the potential for Aspergillus sp XJ-2 CGMCC12963 in the treatment of wastewater containing anthraquinone dyes.

Growth kinetics and biodeterioration of polypropylene microplastics by Bacillus sp. and Rhodococcus sp. isolated from mangrove sediment.

Science.gov (United States)

Auta, H S; Emenike, C U; Jayanthi, B; Fauziah, S H

2018-02-01

Interest in the biodegradation of microplastics is due to their ubiquitous distribution, availability, high persistence in the environment and deleterious impact on marine biota. The present study evaluates the growth response and mechanism of polypropylene (PP) degradation by Bacillus sp. strain 27 and Rhodococcus sp. strain 36 isolated from mangrove sediments upon exposure to PP microplastics. Both bacteria strains were able to utilise PP microplastic for growth as confirmed by the reduction of the polymer mass. The weight loss was 6.4% by Rhodococcus sp. strain 36 and 4.0% by Bacillus sp. strain 27 after 40days of incubation. PP biodegradation was further confirmed using Fourier-transform infrared spectroscopy and scanning electron microscopy analyses, which revealed structural and morphological changes in the PP microplastics with microbial treatment. These analyses showed that the isolates can colonise, modify and utilise PP microplastics as carbon source. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aerobic degradation of buprofezin via novel degradation intermediates by Rhodococcus sp. strain RX-3

OpenAIRE

Ruixue Li; Chun Dai; Guangli Wang; Shaoxian Wu; Yubao Gong; Yuanyuan Jiang; Zhijia Wang; Naiyue Sun

2016-01-01

Buprofezin is a commonly used chemical with satisfactory efficacy against sucking insect pests, but its disposal causes serious environmental problems. In this study, a bacterial strain RX-3 isolated by continuous enrichment from buprofezin-treated soil was tested for biodegradation of buprofezin. The bacteria were most similar to Rhodococcus sp. based on their morphological, physiological and biochemical characteristics, as well as phylogenetic placement inferred from 16S rRNA gene sequence....

Recognition and repair of 2-aminofluorene- and 2-(acetylamino)fluorene-DNA adducts by UVRABC nuclease

International Nuclear Information System (INIS)

Pierce, J.R.; Case, R.; Tang, Moonshong

1989-01-01

Recognition of damage induced by N-hydroxy-2-aminofluorene (N-OH-AF) and N-acetoxy-2-(acetylamino)fluorene (NAAAF) in both φX174 RFI supercoiled DNA and a linear DNA fragment by purified UVRA, UVRB, and UVRC proteins was investigated. The authors have previously demonstrated that N-OH-AF and NAAAF treatments produce N-(deoxyguanosin-8-yl)-2-aminofluorene (dG-C8-AF) and N-(deoxyguanosin-8-yl)-2-(acetylamino)fluorene (dG-C8-AAF), respectively, in DNA. Using a piperidine cleavage method and DNA sequence analysis, they have found that all guanine residues can be modified by N-OH-AF and NAAAF. These two kinds of adducts have different impacts on the DNA helix structure; while dG-C8-AF maintains the anti configuration, dG-C8-AAF is in the syn form. φX174 RF DNA-Escherichia coli transfection results indicate that while the uvrA, uvrB, and uvrC gene products are needed to repair dG-C8-AAF, the uvrC, but not the uvrA or uvrB gene products, is needed for repair of dG-C8-Af. However, they have found that in vitro the UVRA, UVRB, and UVRC proteins must work in concert to nick both dG-C8-AF and dG-C8-AAF. In general, the reactions of UVRABC nuclease toward dG-C8-AF are similar to those toward dG-C8-AAF; it incises seven to eight nucleotides from the 5' side and three to four nucleotides from the 3' side of the DNA adduct. Evidence is presented to suggest that hydrolysis on the 3' and 5' sides of the damaged base by UVRABC nuclease is not simultaneous and that at least occasionally hydrolysis occurs only on the 3' side or on the 5' side of the damage site. The possible mechanisms of UVRABC nuclease incision for AF-DNA are discussed

Azoarcus sp. CIB, an anaerobic biodegrader of aromatic compounds shows an endophytic lifestyle.

Directory of Open Access Journals (Sweden)

Helga Fernández

Full Text Available BACKGROUND: Endophytic bacteria that have plant growth promoting traits are of great interest in green biotechnology. The previous thought that the Azoarcus genus comprises bacteria that fit into one of two major eco-physiological groups, either free-living anaerobic biodegraders of aromatic compounds or obligate endophytes unable to degrade aromatics under anaerobic conditions, is revisited here. METHODOLOGY/PRINCIPAL FINDINGS: Light, confocal and electron microscopy reveal that Azoarcus sp. CIB, a facultative anaerobe β-proteobacterium able to degrade aromatic hydrocarbons under anoxic conditions, is also able to colonize the intercellular spaces of the rice roots. In addition, the strain CIB displays plant growth promoting traits such nitrogen fixation, uptake of insoluble phosphorus and production of indoleacetic acid. Therefore, this work demonstrates by the first time that a free-living bacterium able to degrade aromatic compounds under aerobic and anoxic conditions can share also an endophytic lifestyle. The phylogenetic analyses based on the 16S rDNA and nifH genes confirmed that obligate endophytes of the Azoarcus genus and facultative endophytes, such as Azoarcus sp. CIB, locate into different evolutionary branches. CONCLUSIONS/SIGNIFICANCE: This is the first report of a bacterium, Azoarcus sp. CIB, able to degrade anaerobically a significant number of aromatic compounds, some of them of great environmental concern, and to colonize the rice as a facultative endophyte. Thus, Azoarcus sp. CIB becomes a suitable candidate for a more sustainable agricultural practice and phytoremediation technology.

Evidence for the microbial degradation of imidacloprid in soils of Cameron Highlands

Directory of Open Access Journals (Sweden)

Nasrin Sabourmoghaddam

2015-06-01

Full Text Available Imidacloprid (1-[(6-chloro-3-pyridinylmethyl]-N-nitro-2-imidazolidinimine, with a novel mode of action is a recent systemic and contact insecticide with high activity against a wide range of pests. Continuous dispersion of this pesticide in the environment and its stability in soil results in environmental pollution which demands remediation. The present research was attempted to isolate and characterize imidacloprid degrading bacteria from vegetable farms of Cameron Highlands in Malaysia. The degradation ability of the isolates was tested in minimal salt medium (MSM for a duration of 25 days and the selected strains were characterized based on their biochemical and molecular characteristics. Levels of imidacloprid in MSM medium were analyzed by high performance liquid chromatography (HPLC. Among 50 soil bacterial isolates Bacillus sp., Brevibacterium sp., Pseudomonas putida F1, Bacillus subtilis and Rhizobium sp. were able to degrade 25.36–45.48% of the initial amount of imidacloprid at the concentration of 25 mg L−1 in C limited media. Brevibacterium sp. was isolated from organic farms that had never been exposed to imidacloprid while the other farms had previously been exposed to different levels of imidacloprid. All bacteria introduced in this study were among the first reports of imidacloprid degrading isolates in C limited media from tropical soil. Therefore, the results of this study demonstrate the effectiveness of using soil bacteria for microbial degradation of imidacloprid. These findings suggest that these strains may be promising candidates for bioremediation of imidacloprid-contaminated soils.

Degradation of textile dyes by cyanobacteria.

Science.gov (United States)

Dellamatrice, Priscila Maria; Silva-Stenico, Maria Estela; Moraes, Luiz Alberto Beraldo de; Fiore, Marli Fátima; Monteiro, Regina Teresa Rosim

Dyes are recalcitrant compounds that resist conventional biological treatments. The degradation of three textile dyes (Indigo, RBBR and Sulphur Black), and the dye-containing liquid effluent and solid waste from the Municipal Treatment Station, Americana, São Paulo, Brazil, by the cyanobacteria Anabaena flos-aquae UTCC64, Phormidium autumnale UTEX1580 and Synechococcus sp. PCC7942 was evaluated. The dye degradation efficiency of the cyanobacteria was compared with anaerobic and anaerobic-aerobic systems in terms of discolouration and toxicity evaluations. The discoloration was evaluated by absorption spectroscopy. Toxicity was measured using the organisms Hydra attenuata, the alga Selenastrum capricornutum and lettuce seeds. The three cyanobacteria showed the potential to remediate textile effluent by removing the colour and reducing the toxicity. However, the growth of cyanobacteria on sludge was slow and discoloration was not efficient. The cyanobacteria P. autumnale UTEX1580 was the only strain that completely degraded the indigo dye. An evaluation of the mutagenicity potential was performed by use of the micronucleus assay using Allium sp. No mutagenicity was observed after the treatment. Two metabolites were produced during the degradation, anthranilic acid and isatin, but toxicity did not increase after the treatment. The cyanobacteria showed the ability to degrade the dyes present in a textile effluent; therefore, they can be used in a tertiary treatment of effluents with recalcitrant compounds. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Surfaces wettability and morphology modulation in a fluorene derivative self-assembly system

Energy Technology Data Exchange (ETDEWEB)

Cao, Xinhua, E-mail: caoxhchem@163.com; Gao, Aiping; Zhao, Na; Yuan, Fangyuan; Liu, Chenxi; Li, Ruru

2016-04-15

Graphical abstract: - Highlights: • The different structures could be obtained in this self-assembly system. • A water-drop could freely roll on the xerogel film with the sliding angle of 15.0. • The superhydrophobic surface can be obtained via supramolecular self-assembly. - Abstract: A new organogelator based on fluorene derivative (gelator 1) was designed and synthesized. Organogels could be obtained via the self-assembly of the derivative in acetone, toluene, ethyl acetate, hexane, DMSO and petroleum ether. The self-assembly process was thoroughly characterized using field-emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), UV–vis, FT-IR and the contact angle. Surfaces with different morphologies and wetting properties were formed via the self-assembly of gelator 1 in the six different solvents. Interestingly, a superhydrophobic surface with a contact angle of 150° was obtained from organogel 1 in DMSO and exhibited the lotus-effect. The sliding angle necessary for a water droplet to move on the glass was only 15°. Hydrogen bonding and van der Waals forces were attributed as the main driving forces for gel formation.

Ecotoxicity by the biodegradation of alkylphenol polyethoxylates depends on the effect of trace elements.

Science.gov (United States)

Hotta, Yudai; Hosoda, Akifumi; Sano, Fumihiko; Wakayama, Manabu; Niwa, Katsuki; Yoshikawa, Hiromichi; Tamura, Hiroto

2010-01-27

The bacteria Sphingomonas sp. strain BSN22, isolated from bean fields, degraded octylphenol polyethoxylates (OPEO(n)) to octylphenol (OP) under aerobic conditions. This biodegradation mechanism proceeded by the following two-step degradation process: (1) degradation of OPEO(n) to octylphenol triethoxylate (OPEO(3)), (2) degradation from OPEO(3) to OP via octylphenoxy acetic acid (OPEC(1)). The chemical structure of OPEC(1) was confirmed by analysis using (18)O-labeled water. Quantitative studies revealed that magnesium (Mg(2+)) and calcium (Ca(2+)) ions were essential for the biodegradation of OPEO(n). Furthermore, the rate of biodegradation was especially accelerated by ferric ions (Fe(3+)), and the accumulated amounts of endocrine active chemicals, such as OP, OPEO(1), and OPEC(1), significantly increased to the concentration of 22.8, 221.7, and 961.1 microM in the presence of 37.0 microM Fe(3+), respectively. This suggests that environmental elements significantly influence the resultant ecotoxicity as well as the rate of their biodegradation in the environment. This study on the mechanism of OPEO(n) biodegradation may play an important role in understanding and managing environmental safety, including drinking water safety.

Degradation of crude oil by marine cyanobacteria

Digital Repository Service at National Institute of Oceanography (India)

Raghukumar, C.; Vipparty, V.; David, J.J.; Chandramohan, D.

The marine cyanobacteria Oscillatoria salina Biswas, Plectonema terebrans Bornet et Flanhault and Aphanocapsa sp. degraded Bombay High crude oil when grown in artificial seawater nutrients as well as in plain natural seawater. Oil removals...

BIOREMEDIATION PERSPECTIVES USING AUTOCHTHONOUS SPECIES OF Trichoderma sp. FOR DEGRADATION OF ATRAZINE IN AGRICULTURAL SOIL FROM THE TULANCINGO VALLEY, HIDALGO, MEXICO

Directory of Open Access Journals (Sweden)

Margarita Islas Pelcastre

2013-08-01

Full Text Available The objective of this study was to show an in vitro bioremediation methodology for atrazine-contaminated soils through the use of local strains of native fungi isolated from the Phaseolus vulgaris L rhizosphere present in cultivable soils as well as to evaluate its resistance and capacity for atrazine degradation. A Trichoderma sp. species was identified in three cultivable soils from the Tulancingo Hidalgo, México region (contaminated with and without atrazine, which resisted atrazine concentrations of 10,000 mg L-1.  Tests showed that the strain grows exponentially in atrazine-contaminated soil over a range of 105-106 CFU g-1 in 15 days using atrazine as the only carbon and nitrogen source, while the control and witress showed a decrease of 100-103 UFC g-1 in the same period of time. For the atrazine degradation experiments, a treatment of the application of Trichoderma (104 - 105 CFU mL-1 was applied to sterilized and non-sterilized soil contaminated with 500 mg Kg-1 of atrazine, evaluated at four time intervals (5, 10, 20 and 40 days. Statistical differences were found (α=0.050, Tukey among treatments with the fungi and the test days. The native Trichoderma strain degraded 89% of the atrazine in 40 days. It showed that it is viable and cultivable in soil bioremediation.

Sintésis y propiedades fotofísicas de compuestos de platino y paladio con ligandos (fluoren-9-iliden) metanoditiolato

OpenAIRE

Pérez Cadenas, María

2007-01-01

En este trabajo se ha realizado la síntesis y caracterización estructural de complejos de platino y paladio con el ligando (fluoren-9-iliden) metanoditiolato y sus derivados 2,7-disustituídos. Se ha estudiado la influencia del carácter fuertemente dador de los nuevos ligandos en las estructuras, reactividades, comportamiento redox y propiedades fotofísicas de sus complejos metálicos, así como las posibilidades de agregación de centros metálicos adicionales y su influencia en las propiedades f...

Syntrophorhabdus aromaticivorans gen. nov., sp. nov., the first cultured anaerobe capable of degrading phenol to acetate in obligate syntrophic associations with a hydrogenotrophic methanogen.

Science.gov (United States)

Qiu, Yan-Ling; Hanada, Satoshi; Ohashi, Akiyoshi; Harada, Hideki; Kamagata, Yoichi; Sekiguchi, Yuji

2008-04-01

Phenol degradation under methanogenic conditions has long been studied, but the anaerobes responsible for the degradation reaction are still largely unknown. An anaerobe, designated strain UI(T), was isolated in a pure syntrophic culture. This isolate is the first tangible, obligately anaerobic, syntrophic substrate-degrading organism capable of oxidizing phenol in association with an H(2)-scavenging methanogen partner. Besides phenol, it could metabolize p-cresol, 4-hydroxybenzoate, isophthalate, and benzoate. During the degradation of phenol, a small amount of 4-hydroxybenzoate (a maximum of 4 microM) and benzoate (a maximum of 11 microM) were formed as transient intermediates. When 4-hydroxybenzoate was used as the substrate, phenol (maximum, 20 microM) and benzoate (maximum, 92 microM) were detected as intermediates, which were then further degraded to acetate and methane by the coculture. No substrates were found to support the fermentative growth of strain UI(T) in pure culture, although 88 different substrates were tested for growth. 16S rRNA gene sequence analysis indicated that strain UI(T) belongs to an uncultured clone cluster (group TA) at the family (or order) level in the class Deltaproteobacteria. Syntrophorhabdus aromaticivorans gen. nov., sp. nov., is proposed for strain UI(T), and the novel family Syntrophorhabdaceae fam. nov. is described. Peripheral 16S rRNA gene sequences in the databases indicated that the proposed new family Syntrophorhabdaceae is largely represented by abundant bacteria within anaerobic ecosystems mainly decomposing aromatic compounds.

Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

Science.gov (United States)

Fei, Yong-tao; Liu, Dong-mei; Luo, Tong-hui; Chen, Gu; Wu, Hui; Li, Li; Yu, Yi-gang

2014-01-01

Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010) was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (PLactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively) of the L-lactate dehydrogenase 1 (L-ldh1) gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

Microbialproperty improvement of saline-alkali soil for vegetable cultivation in Shanghai coastal area and its evaluation

Directory of Open Access Journals (Sweden)

KOU Yiming

2015-10-01

Full Text Available In order to improve the fertility of saline-alkali soil in Shanghai coastal area,and make it suitable for vegetable cultiration,in the study,the saline-alkali soil was mixed with organic fertilizer,and then sprayed with composite microbes,which have the ability of the synergistically degrading organic substrate.The results showed that the saline-alkali soil added with 5∶1 organic fertilizer can rapidly increase the utilization ability soil organic matter.The soil microbial populations and microbial diversity index were significantly improved when applied with the 0.5% composite microbial liquid which containeds 1∶3∶3∶1 of Bacillus licheniformis,Pseudomonas sp., Flavobacterium sp.and Sphingomonas sp..At the same time,the enzymology indicators of soil urease,phosphatase,cellulase and catalase increased significantly.The vegetable cultivation experiments showed that:the biomass of Brassica chinensis nearly doubled in the original saline-alkali soil,while the yield of organic fertilizer increased 30.2% after 50 days.The research result on of the biological improvement for saline-alkali soil will have good application value in vegetable planting in coastal saline-alkali soil.

Population dynamics of biofilm development during start-up of a butyrate-degrading fluidized-bed reactor

Energy Technology Data Exchange (ETDEWEB)

Zellner, G.; Geveke, M.; Diekmann, H. (Hannover Univ. (Germany). Inst. fuer Mikrobiologie); Conway de Macario, E. (New York State Dept. of Health, Albany, NY (United States). Wadsworth Center for Laboratories and Research)

1991-12-01

Population dynamics during start-up of a fluidized-bed reactor with butyrate or butyrate plus acetate as sole substrates as well as biofilm development on the sand substratum were studied microbiologically, immunologically and by scanning electron microscopy. An adapted syntrophic consortium consisting of Syntrophospora sp., Methanothrix soehngenii, Methanosarcina mazei and Methanobrevibacter arboriphilus or Methanogenium sp. achieved high-rate butyrate degradation to methane and carbon dioxide. Desulfovibrio sp., Methanocorpusculum sp., and Methanobacterium sp. were also present in lower numbers. Immunological analysis demonstrated methanogens antigenically related to Methanobrevibacter ruminantium M1, Methanosarcina mazei S6, M. thermophila TM1, Methanobrevibacter arboriphilus AZ and Methanothrix soehngenii Opfikon in the biofilm. Immunological analysis also showed that the organisms isolated from the butyrate-degrading culture used as a source of inoculum were related to M. soehngenii Opfikon, Methanobacterium formicium MF and Methanospirillum hungatei JF1. (orig.).

Degradation of polynuclear aromatic hydrocarbons by two strains of Pseudomonas.

Science.gov (United States)

Nwinyi, Obinna C; Ajayi, Oluseyi O; Amund, Olukayode O

2016-01-01

The goal of this investigation was to isolate competent polynuclear aromatic hydrocarbons degraders that can utilize polynuclear aromatic hydrocarbons of former industrial sites at McDoel Switchyard in Bloomington, Indiana. Using conventional enrichment method based on soil slurry, we isolated, screened and purified two bacterial species strains PB1 and PB2. Applying the ribotyping technique using the 16S rRNA gene analysis, the strains were assigned to the genus Pseudomonas (Pseudomonas plecoglossicida strain PB1 and Pseudomonas sp. PB2). Both isolates showed promising metabolic capacity on pyrene sprayed MS agar plates during the preliminary investigations. Using time course studies in the liquid cultures at calculated concentrations 123, 64, 97 and 94ppm for naphthalene, chrysene, fluroanthene and pyrene, P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 showed partial utilization of the polynuclear aromatic hydrocarbons. Naphthalene was degraded between 26% and 40%, chrysene 14% and 16%, fluroanthene 5% and 7%; pyrene 8% and 13% by P. plecoglossicida strain PB1 and Pseudomonas sp. PB2 respectively. Based on their growth profile, we developed a model R(2)=1 to predict the degradation rate of slow polynuclear aromatic hydrocarbon-degraders where all the necessary parameters are constant. From this investigation, we confirm that the former industrial site soil microbial communities may be explored for the biorestoration of the industrial site. Copyright © 2016. Published by Elsevier Editora Ltda.

Polycyclic aromatic hydrocarbons degradation by marine-derived basidiomycetes: optimization of the degradation process.

Science.gov (United States)

Vieira, Gabriela A L; Magrini, Mariana Juventina; Bonugli-Santos, Rafaella C; Rodrigues, Marili V N; Sette, Lara D

2018-05-03

Pyrene and benzo[a]pyrene (BaP) are high molecular weight polycyclic aromatic hydrocarbons (PAHs) recalcitrant to microbial attack. Although studies related to the microbial degradation of PAHs have been carried out in the last decades, little is known about degradation of these environmental pollutants by fungi from marine origin. Therefore, this study aimed to select one PAHs degrader among three marine-derived basidiomycete fungi and to study its pyrene detoxification/degradation. Marasmiellus sp. CBMAI 1062 showed higher levels of pyrene and BaP degradation and was subjected to studies related to pyrene degradation optimization using experimental design, acute toxicity, organic carbon removal (TOC), and metabolite evaluation. The experimental design resulted in an efficient pyrene degradation, reducing the experiment time while the PAH concentration applied in the assays was increased. The selected fungus was able to degrade almost 100% of pyrene (0.08mgmL -1 ) after 48h of incubation under saline condition, without generating toxic compounds and with a TOC reduction of 17%. Intermediate metabolites of pyrene degradation were identified, suggesting that the fungus degraded the compound via the cytochrome P450 system and epoxide hydrolases. These results highlight the relevance of marine-derived fungi in the field of PAH bioremediation, adding value to the blue biotechnology. Copyright © 2018. Published by Elsevier Editora Ltda.

The marine bacterium Marinobacter hydrocarbonoclasticus SP17 degrades a wide range of lipids and hydrocarbons through the formation of oleolytic biofilms with distinct gene expression profiles.

Science.gov (United States)

Mounier, Julie; Camus, Arantxa; Mitteau, Isabelle; Vaysse, Pierre-Joseph; Goulas, Philippe; Grimaud, Régis; Sivadon, Pierre

2014-12-01

Hydrophobic organic compounds (mainly lipids and hydrocarbons) represent a significant part of the organic matter in marine waters, and their degradation has an important impact in the carbon fluxes within oceans. However, because they are nearly insoluble in the water phase, their degradation by microorganisms occurs at the interface with water and thus requires specific adaptations such as biofilm formation. We show that Marinobacter hydrocarbonoclasticus SP17 develops biofilms, referred to as oleolytic biofilms, on a large variety of hydrophobic substrates, including hydrocarbons, fatty alcohols, fatty acids, triglycerides, and wax esters. Microarray analysis revealed that biofilm growth on n-hexadecane or triolein involved distinct genetic responses, together with a core of common genes that might concern general mechanisms of biofilm formation. Biofilm growth on triolein modulated the expression of hundreds of genes in comparison with n-hexadecane. The processes related to primary metabolism and genetic information processing were downregulated. Most of the genes that were overexpressed on triolein had unknown functions. Surprisingly, their genome localization was restricted to a few regions identified as putative genomic islands or mobile elements. These results are discussed with regard to the adaptive responses triggered by M. hydrocarbonoclasticus SP17 to occupy a specific niche in marine ecosystems. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Naphthalene degradation by bacterial consortium (DV-AL) developed from Alang-Sosiya ship breaking yard, Gujarat, India.

Science.gov (United States)

Patel, Vilas; Jain, Siddharth; Madamwar, Datta

2012-03-01

Naphthalene degrading bacterial consortium (DV-AL) was developed by enrichment culture technique from sediment collected from the Alang-Sosiya ship breaking yard, Gujarat, India. The 16S rRNA gene based molecular analyzes revealed that the bacterial consortium (DV-AL) consisted of four strains namely, Achromobacter sp. BAB239, Pseudomonas sp. DV-AL2, Enterobacter sp. BAB240 and Pseudomonas sp. BAB241. Consortium DV-AL was able to degrade 1000 ppm of naphthalene in Bushnell Haas medium (BHM) containing peptone (0.1%) as co-substrate with an initial pH of 8.0 at 37°C under shaking conditions (150 rpm) within 24h. Maximum growth rate and naphthalene degradation rate were found to be 0.0389 h(-1) and 80 mg h(-1), respectively. Consortium DV-AL was able to utilize other aromatic and aliphatic hydrocarbons such as benzene, phenol, carbazole, petroleum oil, diesel fuel, and phenanthrene and 2-methyl naphthalene as sole carbon source. Consortium DV-AL was also efficient to degrade naphthalene in the presence of other pollutants such as petroleum hydrocarbons and heavy metals. Copyright © 2011 Elsevier Ltd. All rights reserved.

Crude oil biodegradation aided by biosurfactants from Pseudozyma sp. NII 08165 or its culture broth.

Science.gov (United States)

Sajna, Kuttuvan Valappil; Sukumaran, Rajeev Kumar; Gottumukkala, Lalitha Devi; Pandey, Ashok

2015-09-01

The aim of this work was to evaluate the biosurfactants produced by the yeast Pseudozyma sp. NII 08165 for enhancing the degradation of crude oil by a model hydrocarbon degrading strain, Pseudomonas putida MTCC 1194. Pseudozyma biosurfactants were supplemented at various concentrations to the P. putida culture medium containing crude oil as sole carbon source. Supplementation of the biosurfactants enhanced the degradation of crude oil by P. putida; the maximum degradation of hydrocarbons was observed with a 2.5 mg L(-1) supplementation of biosurfactants. Growth inhibition constant of the Pseudozyma biosurfactants was 11.07 mg L(-1). It was interesting to note that Pseudozyma sp. NII 08165 alone could also degrade diesel and kerosene. Culture broth of Pseudozyma containing biosurfactants resulted up to ∼46% improvement in degradation of C10-C24 alkanes by P. putida. The enhancement in degradation efficiency of the bacterium with the culture broth supplementation was even more pronounced than that with relatively purer biosurfactants. Copyright © 2015 Elsevier Ltd. All rights reserved.

Combined use of alkane-degrading and plant growth-promoting bacteria enhanced phytoremediation of diesel contaminated soil.

Science.gov (United States)

Tara, Nain; Afzal, Muhammad; Ansari, Tariq M; Tahseen, Razia; Iqbal, Samina; Khan, Qaiser M

2014-01-01

Inoculation of plants with pollutant-degrading and plant growth-promoting microorganisms is a simple strategy to enhance phytoremediation activity. The objective of this study was to determine the effect of inoculation of different bacterial strains, possessing alkane-degradation and 1-amino-cyclopropane-1 -carboxylic acid (ACC) deaminase activity, on plant growth and phytoremediation activity. Carpet grass (Axonopus affinis) was planted in soil spiked with diesel (1% w/w) for 90 days and inoculated with different bacterial strains, Pseudomonas sp. ITRH25, Pantoea sp. BTRH79 and Burkholderia sp. PsJN, individually and in combination. Generally, bacterial application increased total numbers of culturable hydrocarbon-degrading bacteria in the rhizosphere ofcarpet grass, plant biomass production, hydrocarbon degradation and reduced genotoxicity. Bacterial strains possessing different beneficial traits affect plant growth and phytoremediation activity in different ways. Maximum bacterial population, plant biomass production and hydrocarbon degradation were achieved when carpet grass was inoculated with a consortium of three strains. Enhanced plant biomass production and hydrocarbon degradation were associated with increased numbers of culturable hydrocarbon-degrading bacteria in the rhizosphere of carpet grass. The present study revealed that the combined use of different bacterial strains, exhibiting different beneficial traits, is a highly effective strategy to improve plant growth and phytoremediation activity.

Isolation and characterization of bacteria capable of degrading polycyclic aromatic hydrocarbons (PAHs) and organophosphorus pesticides from PAH-contaminated soil in Hilo, Hawaii.

Science.gov (United States)

Seo, Jong-Su; Keum, Young-Soo; Harada, Renee M; Li, Qing X

2007-07-11

Nineteen bacterial strains were isolated from petroleum-contaminated soil in Hilo, HI, and characterized by two different spray-plated methods, turbidity test in liquid medium, and 16S rRNA gene sequence analysis. Analysis of the soil showed 13 polycyclic aromatic hydrocarbons (PAHs) in a range from 0.6 to 30 mg/kg of dry weight each and 12 PAH metabolites. Five distinct bacterial strains (C3, C4, P1-1, JS14, and JS19b1) selected from preliminary plating and turbidity tests were further tested for PAH degradation through single PAH degradation assay. Strains C3, C4, and P1-1 degraded phenanthrene (40 mg/L) completely during 7 days of incubation. Strain JS14 degraded fluoranthene (40 mg/L) completely during 10 days of incubation. Strain JS19b1 degraded 100% of phenanthrene (40 mg/L) in 7 days, 77% of fluorene (40 mg/L) in 14 days, 97% of fluoranthene (40 mg/L) in 10 days, and 100% of pyrene (40 mg/L) in 14 days. Turbidity tests showed that strains P1-1, JS14, and JS19b1 utilized several organophosphorus pesticides as growth substrate. P1-1 can degrade carbofenothion, chlorfenvinphos, diazinon, fonofos, and pirimiphos-methyl. JS14 can transform chlorfenvinphos and diazinon. JS19b1 can break down diazinon, pirimiphos-methyl, and temephos.

Enhanced selection of micro-aerobic pentachlorophenol degrading granular sludge

Energy Technology Data Exchange (ETDEWEB)

Lv, Yuancai, E-mail: donkey1204@hotmail.com [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Chen, Yuancai, E-mail: chenyc@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Song, Wenzhe, E-mail: songwenzhe007@126.com [Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Hu, Yongyou, E-mail: ppyyhu@scut.edu.cn [State Key Laboratory of Pulp and Paper Engineering, College of Light Industry and Food Science, South China University of Technology, Guangzhou 510640 (China); Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China)

2014-09-15

-aerobic condition and PCP on microbial community. Furthermore, nucleotide sequencing indicated that the main microorganisms for PCP degradation might be related to Actinobacterium and Sphingomonas. These results provided insights into situ bioremediation of environments contaminated by PCP and had practical implications for the strategies of PCP degradation.

Enhanced selection of micro-aerobic pentachlorophenol degrading granular sludge

International Nuclear Information System (INIS)

Lv, Yuancai; Chen, Yuancai; Song, Wenzhe; Hu, Yongyou

2014-01-01

PCP on microbial community. Furthermore, nucleotide sequencing indicated that the main microorganisms for PCP degradation might be related to Actinobacterium and Sphingomonas. These results provided insights into situ bioremediation of environments contaminated by PCP and had practical implications for the strategies of PCP degradation

[Oil degradation by basidiomycetes in soil and peat at low temperatures].

Science.gov (United States)

Kulikova, N A; Klein, O I; Pivchenko, D V; Landesman, E O; Pozdnyakova, N N; Turkovskaya, O V; Zaichik, B Ts; Ruzhitskii, A O; Koroleva, O V

2016-01-01

A total of 17 basidiomycete strains causing white rot and growing on oil-contaminated substrates have been screened. Three strains with high (Steccherinum murashkinskyi), average (Trametes maxima), and low (Pleurotus ostreatus) capacities for the colonization of oil-contaminated substrates have been selected. The potential for degrading crude oil hydrocarbons has been assessed with the use of fungi grown on nonsterile soil and peat at low temperatures. Candida sp. and Rhodococcus sp. commercial strains have been used as reference organisms with oil-degrading ability. All microorganisms introduced in oil-contaminated soil have proved to be ineffective, whereas the inoculation of peat with basidiomycetes and oil-degrading microorganisms accelerated the destruction of oil hydrocarbons. The greatest degradation potential of oil-aliphatic hydrocarbons has been found in S. murashlinskyi. T. maxima turned out to be the most successful in degrading aromatic hydrocarbons. It has been suggested that aboriginal microflora contributes importantly to the effectiveness of oil-destructing microorganisms. T. maxima and S. murashkinskyi strains are promising for further study as oil-oxidizing agents during bioremediation of oil-contaminated peat soil under conditions of low temperatures.

Effects of different culture media on biodegradation of triclosan by Rhodotorula mucilaginosa and Penicillium sp.

Science.gov (United States)

Ertit Taştan, Burcu; Özdemir, Caner; Tekinay, Turgay

Triclosan is an antimicrobial agent and a persistent pollutant. The biodegradation of triclosan is dependent on many variables including the biodegradation organism and the environmental conditions. Here, we evaluated the triclosan degradation potential of two fungi strains, Rhodotorula mucilaginosa and Penicillium sp., and the rate of its turnover to 2,4-dichlorophenol (2,4-DCP). Both of these strains showed less susceptibility to triclosan when grown in minimal salt medium. In order to further evaluate the effects of environmental conditions on triclosan degradation, three different culture conditions including original thermal power plant wastewater, T6 nutrimedia and ammonium mineral salts medium were used. The maximum triclosan degradation yield was 48% for R. mucilaginosa and 82% for Penicillium sp. at 2.7 mg/L triclosan concentration. Biodegradation experiments revealed that Penicillium sp. was more tolerant to triclosan. Scanning electron microscopy micrographs also showed the morphological changes of fungus when cells were treated with triclosan. Overall, these fungi strains could be used as effective microorganisms in active uptake (degradation) and passive uptake (sorption) of triclosan and their efficiency can be increased by optimizing the culture conditions.

Exposure of Cucurbita pepo to DDE-contamination alters the endophytic community: A cultivation dependent vs a cultivation independent approach.

Science.gov (United States)

Eevers, N; Hawthorne, J R; White, J C; Vangronsveld, J; Weyens, N

2016-02-01

2,2-bis(p-chlorophenyl)-1,1-dichloro-ethylene (DDE) is the most abundant and persistent degradation product of the pesticide 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and is encountered in contaminated soils worldwide. Both DDE and DDT are classified as Persistent Organic Pollutants (POPs) due to their high hydrophobicity and potential for bioaccumulation and biomagnification in the food chain. Zucchini (Cucurbita pepo ssp. pepo) has been shown to accumulate high concentrations of DDE and other POPs and has been proposed as a phytoremediation tool for contaminated soils. The endophytic bacteria associated with this plant may play an important role in the remedial process. Therefore, this research focuses on changes in endophytic bacterial communities caused by the exposure of C. pepo to DDE. The total bacterial community was investigated using cultivation-independent 454 pyrosequencing, while the cultivable community was identified using cultivation-dependent isolation procedures. For both procedures, increasing numbers of endophytic bacteria, as well as higher diversities of genera were observed when plants were exposed to DDE. Several bacterial genera such as Stenotrophomonas sp. and Sphingomonas sp. showed higher abundance when DDE was present, while, for example Pseudomonas sp. showed a significantly lower abundance in the presence of DDE. These findings suggest tolerance of different bacterial strains to DDE, which might be incorporated in further investigations to optimize phytoremediation with the possible use of DDE-degrading endophytes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Elucidating MTBE degradation in a mixed consortium using a multidisciplinary approach.

Science.gov (United States)

Bastida, Felipe; Rosell, Mònica; Franchini, Alessandro G; Seifert, Jana; Finsterbusch, Stefanie; Jehmlich, Nico; Jechalke, Sven; von Bergen, Martin; Richnow, Hans H

2010-08-01

The structure and function of a microbial community capable of biodegrading methyl-tert-butyl ether (MTBE) was characterized using compound-specific stable isotope analysis (CSIA), clone libraries and stable isotope probing of proteins (Protein-SIP). The enrichment culture (US3-M), which originated from a gasoline-impacted site in the United States, has been enriched on MTBE as the sole carbon source. The slope of isotopic enrichment factors (epsilon(C) of -2.29+/-0.03 per thousand; epsilon(H) of -58+/-6 per thousand) for carbon and hydrogen discrimination (Deltadelta(2)H/Deltadelta(13)C) was on average equal to Lambda=24+/-2, a value closely related to the reaction mechanism of MTBE degradation in Methylibium petroleiphilum PM1. 16S rRNA gene libraries revealed sequences belonging to M. petroleiphilum PM1, Hydrogenophaga sp., Thiothrix unzii, Rhodobacter sp., Nocardiodes sp. and different Sphingomonadaceae bacteria. Protein-SIP analysis of the culture grown on (13)C-MTBE as the only carbon source revealed that proteins related to members of the Comamonadaceae family, such as Delftia acidovorans, Acidovorax sp. or Comamonas sp., were not (13)C-enriched, whereas proteins related to M. petroleiphilum PM1 showed an average incorporation of 94.5 atom%(13)C. These results indicate a key role for this species in the degradation of MTBE within the US3-M consortia. The combination of CSIA, molecular biology and Protein-SIP facilitated the analysis of an MTBE-degrading mixed culture from a functional and phylogenetic point of view.

In vivo degradation characteristics of poly (β-propiolactone) prepared by radiation-induced polymerization at low temperature

International Nuclear Information System (INIS)

Asano, Masaharu; Yoshida, Masaru; Kaetsu, Isao

1987-01-01

The polymerization rate of β-propiolactone (PL) by irradiation at -78deg C in vacuo inceased markedly with the irradiation dose of up to 50 kGy and then gradually increased at an irradiation dose of up to 200 kGy. The yields of poly(PL) obtained at irradiation doses of 50 and 200 kGy were 22 and 25%, respectively. The polymer was shaped into a cylindrical form with high rigidity and density by pressing at 200 kg/cm 2 in a range of 50deg C to 75deg C. The in vivo degradation of cylindrical specimens was checked by implanting subcutaneously in the back of male Wistar rats. The degrees of in vivo degradation of poly(PL) obtained at 5, 10, 50, 100, 160, and 200 kGy irradiations were 5, 9, 25, 34, 37, and 40%, respectively. The viscosity (η sp /c value) of these polymers showed a decrease tendency with an increase in the irradiation dose. From the relationship between the η sp /c value and the in vivo degradation, it was found that the degree of in vivo degradation had a inflection point at a η sp /c value of 0.4 dl/g (30 kGy irradiation). That is, the in vivo degradation of poly(PL) with η sp /c values below 0.4 dl/g (above 30 kGy irradiation) was markedly accelerated by a slight decrease of viscosity, but such an acceleration was not remarkable at η sp /c values aboves 0.4 dl/g (below 30 kGy irradiation). This may be primarily attributed to the scssion of polymer chains during the irradiation polymerization. The data of X-ray diffraction patterns and DSC curves also showed that the in vivo degradation is influenced by a change in the crystallinity or by a decrease in the melting point of poly(PL). (author)

Molecular characterization of Lactobacillus plantarum DMDL 9010, a strain with efficient nitrite degradation capacity.

Directory of Open Access Journals (Sweden)

Yong-tao Fei

Full Text Available Nitrites commonly found in food, especially in fermented vegetables, are potential carcinogens. Therefore, limiting nitrites in food is critically important for food safety. A Lactobacillus strain (Lactobacillus sp. DMDL 9010 was previously isolated from fermented vegetables by our group, and is not yet fully characterized. A number of phenotypical and genotypical approaches were employed to characterize Lactobacillus sp. DMDL 9010. Its nitrite degradation capacity was compared with four other Lactobacillus strains, including Lactobacillus casei subsp. rhamnosus 719, Lactobacillus delbrueckii subsp. bulgaricu 1.83, Streptococcus thermophilus 1.204, and lactobacillus plantarum 8140, on MRS medium. Compared to these four Lactobacillus strains, Lactobacillus sp. DMDL 9010 had a significantly higher nitrite degradation capacity (P<0.001. Based on 16S rDNA sequencing and sequence comparison, Lactobacillus sp. DMDL 9010 was identified as either Lactobacillus plantarum or Lactobacillus pentosus. To further identify this strain, the flanking regions (922 bp and 806 bp upstream and downstream, respectively of the L-lactate dehydrogenase 1 (L-ldh1 gene were amplified and sequenced. Lactobacillus sp. DMDL 9010 had 98.92 and 76.98% sequence identity in the upstream region with L. plantarum WCFS1 and L. pentosus IG1, respectively, suggesting that Lactobacillu sp. DMDL 9010 is an L. plantarum strain. It was therefore named L. plantarum DMDL 9010. Our study provides a platform for genetic engineering of L. plantarum DMDL 9010, in order to further improve its nitrite degradation capacity.

Polycyclovorans algicola gen. nov., sp. nov., an aromatic-hydrocarbon-degrading marine bacterium found associated with laboratory cultures of marine phytoplankton.

Science.gov (United States)

Gutierrez, Tony; Green, David H; Nichols, Peter D; Whitman, William B; Semple, Kirk T; Aitken, Michael D

2013-01-01

A strictly aerobic, halotolerant, rod-shaped bacterium, designated strain TG408, was isolated from a laboratory culture of the marine diatom Skeletonema costatum (CCAP1077/1C) by enrichment with polycyclic aromatic hydrocarbons (PAHs) as the sole carbon source. 16S rRNA gene sequence analysis placed this organism within the order Xanthomonadales of the class Gammaproteobacteria. Its closest relatives included representatives of the Hydrocarboniphaga-Nevskia-Sinobacter clade (compounds and small organic acids. Notably, it displayed versatility in degrading two- and three-ring PAHs. Moreover, catechol 2,3-dioxygenase activity was detected in lysates, indicating that this strain utilizes the meta-cleavage pathway for aromatic compound degradation. Cells produced surface blebs and contained a single polar flagellum. The predominant isoprenoid quinone of strain TG408 was Q-8, and the dominant fatty acids were C(16:0), C(16:1) ω7c, and C(18:1) ω7c. The G+C content of the isolate's DNA was 64.3 mol% ± 0.34 mol%. On the basis of distinct phenotypic and genotypic characteristics, strain TG408 represents a novel genus and species in the class Gammaproteobacteria for which the name Polycyclovorans algicola gen. nov., sp. nov., is proposed. Quantitative PCR primers targeting the 16S rRNA gene of this strain were developed and used to show that this organism is found associated with other species of marine phytoplankton. Phytoplankton may be a natural biotope in the ocean where new species of hydrocarbon-degrading bacteria await discovery and which contribute significantly to natural remediation processes.

Efficient biotransformation of herbicide diuron by bacterial strain Micrococcus sp. PS-1.

Science.gov (United States)

Sharma, Priyanka; Chopra, Adity; Cameotra, Swaranjit Singh; Suri, C Raman

2010-11-01

A Gram-positive, Micrococcus sp. strain PS-1 capable of utilizing phenylurea herbicide diuron as a sole carbon source at a high concentration (up to 250 ppm) was isolated from diuron storage site by selective enrichment study. The taxonomic characterization with 16S rRNA gene sequencing (1,477 bp) identified PS-1 as a member of Micrococcus sp. It was studied for the degradation of diuron and a range of its analogues (monuron, linuron, monolinuron, chlortoluron and fenuron). The shake flasks experiments demonstrated fast degradation of diuron (up to 96% at 250 ppm within 30 h incubation) with the addition of small quantity (0.01%) of non-ionic detergent. The relative degradation profile by the isolate was in the order of fenuron > monuron > diuron > linuron > monolinuron > chlortoluron. Further, the biochemical characterization of catabolic pathway by spectroscopic and chromatographic techniques demonstrated that the degradation proceeded via formation of dealkylated metabolites to form 3,4-dichloroaniline (3,4-DCA). It was the major metabolite formed, associated with profound increase in degradation kinetics in presence of appropriate additive.

Genes involved in degradation of para-nitrophenol are differentially arranged in form of non-contiguous gene clusters in Burkholderia sp. strain SJ98.

Directory of Open Access Journals (Sweden)

Surendra Vikram

Full Text Available Biodegradation of para-Nitrophenol (PNP proceeds via two distinct pathways, having 1,2,3-benzenetriol (BT and hydroquinone (HQ as their respective terminal aromatic intermediates. Genes involved in these pathways have already been studied in different PNP degrading bacteria. Burkholderia sp. strain SJ98 degrades PNP via both the pathways. Earlier, we have sequenced and analyzed a ~41 kb fragment from the genomic library of strain SJ98. This DNA fragment was found to harbor all the lower pathway genes; however, genes responsible for the initial transformation of PNP could not be identified within this fragment. Now, we have sequenced and annotated the whole genome of strain SJ98 and found two ORFs (viz., pnpA and pnpB showing maximum identity at amino acid level with p-nitrophenol 4-monooxygenase (PnpM and p-benzoquinone reductase (BqR. Unlike the other PNP gene clusters reported earlier in different bacteria, these two ORFs in SJ98 genome are physically separated from the other genes of PNP degradation pathway. In order to ascertain the identity of ORFs pnpA and pnpB, we have performed in-vitro assays using recombinant proteins heterologously expressed and purified to homogeneity. Purified PnpA was found to be a functional PnpM and transformed PNP into benzoquinone (BQ, while PnpB was found to be a functional BqR which catalyzed the transformation of BQ into hydroquinone (HQ. Noticeably, PnpM from strain SJ98 could also transform a number of PNP analogues. Based on the above observations, we propose that the genes for PNP degradation in strain SJ98 are arranged differentially in form of non-contiguous gene clusters. This is the first report for such arrangement for gene clusters involved in PNP degradation. Therefore, we propose that PNP degradation in strain SJ98 could be an important model system for further studies on differential evolution of PNP degradation functions.

Fenpropathrin biodegradation pathway in Bacillus sp. DG-02 and its potential for bioremediation of pyrethroid-contaminated soils.

Science.gov (United States)

Chen, Shaohua; Chang, Changqing; Deng, Yinyue; An, Shuwen; Dong, Yi Hu; Zhou, Jianuan; Hu, Meiying; Zhong, Guohua; Zhang, Lian-Hui

2014-03-12

The widely used insecticide fenpropathrin in agriculture has become a public concern because of its heavy environmental contamination and toxic effects on mammals, yet little is known about the kinetic and metabolic behaviors of this pesticide. This study reports the degradation kinetics and metabolic pathway of fenpropathrin in Bacillus sp. DG-02, previously isolated from the pyrethroid-manufacturing wastewater treatment system. Up to 93.3% of 50 mg L(-1) fenpropathrin was degraded by Bacillus sp. DG-02 within 72 h, and the degradation rate parameters qmax, Ks, and Ki were determined to be 0.05 h(-1), 9.0 mg L(-1), and 694.8 mg L(-1), respectively. Analysis of the degradation products by gas chromatography-mass spectrometry led to identification of seven metabolites of fenpropathrin, which suggest that fenpropathrin could be degraded first by cleavage of its carboxylester linkage and diaryl bond, followed by degradation of the aromatic ring and subsequent metabolism. In addition to degradation of fenpropathrin, this strain was also found to be capable of degrading a wide range of synthetic pyrethroids including deltamethrin, λ-cyhalothrin, β-cypermethrin, β-cyfluthrin, bifenthrin, and permethrin, which are also widely used insecticides with environmental contamination problems with the degradation process following the first-order kinetic model. Bioaugmentation of fenpropathrin-contaminated soils with strain DG-02 significantly enhanced the disappearance rate of fenpropathrin, and its half-life was sharply reduced in the soils. Taken together, these results depict the biodegradation mechanisms of fenpropathrin and also highlight the promising potentials of Bacillus sp. DG-02 in bioremediation of pyrethroid-contaminated soils.

Isolation and Identification of Phenol Degrader Bacteria from Sirjan Golgohar Mine Effluent

Directory of Open Access Journals (Sweden)

Mehdi Hassanshhian

2016-03-01

Full Text Available Phenol and phenolic compounds are highly toxic substances that are found as monoaromatic compounds in various industrial effluents from oil refineries, petrochemical plants, (coal mines, and phenol resin plants. Their discharge into the environment, especially in water resources, causes serious toxicity. Traditionally, physicochemical methods have been used for the removal of phenol and phenolic compounds. Nowadays, bioremediation is known to be the best method for phenol removal from wastewater. The objective of the present study was twofold: isolation and identification of phenol degrading bacteria in the effluent from Golgohar Mine in Sirjan. For this purpose, samples were collected from different sections at Golgohar Mine and its effluent. Phenol degrading bacteria were isolated via enrichment of the samples in the Bushnell Hass medium with phenol used as the only source of carbon and energy. The predominant phenol degrader bacteria were selected by measuring turbidity at 600 nm. The bacteria were subsequently identified by amplification of 16S rRNA with specific primers and PCR sequencing. In this study, 17 strains of phenol degrader bacteria were isolated in soil and wastewater samples collected from different zones of the mine. Screening methods confirmed that 4 strains exhibit a better capability for phenol degradation as evidenced by their capability to degrade 0.4 g/l of phenol. Molecular identification showed that these bacteria belong to the species Pesudomonas sp, Nitrratireductor sp., and Salegentibacter sp. The results also show that the effluent from Golgohar Mine in Sirjan contains many phenol degrading bacteria. The use of these bacteria in the treatment process may lead to a significant reduction in phenol pollution in the mineral effluent.

No evidential correlation between veterinary antibiotic degradation ability and resistance genes in microorganisms during the biodegradation of doxycycline.

Science.gov (United States)

Wen, Xin; Wang, Yan; Zou, Yongde; Ma, Baohua; Wu, Yinbao

2018-01-01

Biodegradation of antibiotic residues in the environment by microorganisms may lead to the generation of antibiotic resistance genes (ARGs), which are of great concern to human health. The aim of this study was to determine whether there is a relationship between the ability to degrade antibiotic doxycycline (DOX) and the development of resistance genes in microorganisms. We isolated and identified ten bacterial strains from a vegetable field that had received long-term manure application as fertilizer and were capable of surviving in a series of DOX concentrations (25, 50, 80, and 100mg/L). Our results showed no evidential correlation between DOX degradation ability and the development of resistance genes among the isolated microorganisms that had high DOX degradation capability (P > 0.05). This was based on the fact that Escherichia sp. and Candida sp. were the most efficient bacterial strains to degrade DOX (92.52% and 91.63%, respectively), but their tetracycline resistance genes showed a relatively low risk of antibiotic resistance in a 7-day experiment. Moreover, the tetM of the ribosomal protection protein genes carried by these two preponderant bacteria was five-fold higher than that carried by other isolates (P genes of three isolates, except for Escherichia sp. and Candida sp., showed remarkable negative correlations (P < 0.05), mainly because tetG markedly increased during the DOX degradation process. Our results concluded that the biodegradation of antibiotic residues may not necessarily lead to the development of ARGs in the environment. In addition, the two bacteria that we isolated, namely, Escherichia sp. and Candida sp., are potential candidates for the engineering of environmentally friendly bacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

Six New Polyacetylenic Alcohols from the Marine Sponges Petrosia sp. and Halichondria sp.

Science.gov (United States)

Gabriel, Adeyemi Francis; Li, Zhen; Kusuda, Ryouhei; Tanaka, Chiaki; Miyamoto, Tomofumi

2015-01-01

Six new polyacetylenic alcohols, termed strongylotriols A and B; pellynols J, K, and L; and isopellynol A, together with three known polyacetylenic alcohols, pellynols A, B, and C were isolated from the marine sponges Petrosia sp., and Halichondria sp. collected in Okinawa, Japan. Their planer structures were determined based on 2D-NMR and mass spectrometric analysis of the degraded products by RuCl3 oxidation. The absolute stereochemistry of isolates was examined by their Mosher's esters. The strongylotriols were found to be optically pure compounds, whereas the pellynols are diastereomeric mixtures at the C-6 position. Proliferation experiments using the HeLa and K562 cell lines suggested that the essential structural units for activity are the "hexa-2,4-diyn-1,6-diol" and "pent-1-en-4-yn-3-ol" on the termini.

Possible linkage of SP6 transcriptional activity with amelogenesis by protein stabilization.

Science.gov (United States)

Utami, Trianna W; Miyoshi, Keiko; Hagita, Hiroko; Yanuaryska, Ryna Dwi; Horiguchi, Taigo; Noma, Takafumi

2011-01-01

Ameloblasts produce enamel matrix proteins such as amelogenin, ameloblastin, and amelotin during tooth development. The molecular mechanisms of ameloblast differentiation (amelogenesis) are currently not well understood. SP6 is a transcription factor of the Sp/KLF family that was recently found to regulate cell proliferation in a cell-type-specific manner. Sp6-deficient mice demonstrate characteristic tooth anomalies such as delayed eruption of the incisors and supernumerary teeth with disorganized amelogenesis. However, it remains unclear how Sp6 controls amelogenesis. In this study, we used SP6 high producer cells to identify SP6 target genes. Based on the observations that long-term culture of SP6 high producer cells reduced SP6 protein expression but not Sp6 mRNA expression, we found that SP6 is short lived and specifically degraded through a proteasome pathway. We established an in vitro inducible SP6 expression system coupled with siRNA knockdown and found a possible linkage between SP6 and amelogenesis through the regulation of amelotin and Rock1 gene expression by microarray analysis. Our findings suggest that the regulation of SP6 protein stability is one of the crucial steps in amelogenesis.

Possible Linkage of SP6 Transcriptional Activity with Amelogenesis by Protein Stabilization

Directory of Open Access Journals (Sweden)

Trianna W. Utami

2011-01-01

Full Text Available Ameloblasts produce enamel matrix proteins such as amelogenin, ameloblastin, and amelotin during tooth development. The molecular mechanisms of ameloblast differentiation (amelogenesis are currently not well understood. SP6 is a transcription factor of the Sp/KLF family that was recently found to regulate cell proliferation in a cell-type-specific manner. Sp6-deficient mice demonstrate characteristic tooth anomalies such as delayed eruption of the incisors and supernumerary teeth with disorganized amelogenesis. However, it remains unclear how Sp6 controls amelogenesis. In this study, we used SP6 high producer cells to identify SP6 target genes. Based on the observations that long-term culture of SP6 high producer cells reduced SP6 protein expression but not Sp6 mRNA expression, we found that SP6 is short lived and specifically degraded through a proteasome pathway. We established an in vitro inducible SP6 expression system coupled with siRNA knockdown and found a possible linkage between SP6 and amelogenesis through the regulation of amelotin and Rock1 gene expression by microarray analysis. Our findings suggest that the regulation of SP6 protein stability is one of the crucial steps in amelogenesis.

Biotransformation of geosmin by terpene-degrading bacteria.

Science.gov (United States)

Two terpene-degrading bacteria that are able to transform geosmin have been identified. Pseudomonas sp. SBR3-tpnb, isolated on -terpinene, converts geosmin to several products; the major products are keto-geosmins. This geosmin transformation ability is inducible by -terpinene. Rhodococcus wratisl...

Characterization and degradation potential of diesel-degrading bacterial strains for application in bioremediation.

Science.gov (United States)

Balseiro-Romero, María; Gkorezis, Panagiotis; Kidd, Petra S; Van Hamme, Jonathan; Weyens, Nele; Monterroso, Carmen; Vangronsveld, Jaco

2017-10-03

Bioremediation of polluted soils is a promising technique with low environmental impact, which uses soil organisms to degrade soil contaminants. In this study, 19 bacterial strains isolated from a diesel-contaminated soil were screened for their diesel-degrading potential, biosurfactant (BS) production, and biofilm formation abilities, all desirable characteristics when selecting strains for re-inoculation into hydrocarbon-contaminated soils. Diesel-degradation rates were determined in vitro in minimal medium with diesel as the sole carbon source. The capacity to degrade diesel range organics (DROs) of strains SPG23 (Arthobacter sp.) and PF1 (Acinetobacter oleivorans) reached 17-26% of total DROs after 10 days, and 90% for strain GK2 (Acinetobacter calcoaceticus). The amount and rate of alkane degradation decreased significantly with increasing carbon number for strains SPG23 and PF1. Strain GK2, which produced BSs and biofilms, exhibited a greater extent, and faster rate of alkane degradation compared to SPG23 and PF1. Based on the outcomes of degradation experiments, in addition to BS production, biofilm formation capacities, and previous genome characterizations, strain GK2 is a promising candidate for microbial-assisted phytoremediation of diesel-contaminated soils. These results are of particular interest to select suitable strains for bioremediation, not only presenting high diesel-degradation rates, but also other characteristics which could improve rhizosphere colonization.

Structural studies of the polysaccharides from the lipopolysaccharides of Azospirillum brasilense Sp246 and SpBr14.

Science.gov (United States)

Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Grinev, Vyacheslav S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

2014-10-29

Lipopolysaccharides from closely related Azospirillum brasilense strains, Sp246 and SpBr14, were obtained by phenol-water extraction. Mild acid hydrolysis of the lipopolysaccharides followed by GPC on Sephadex G-50 resulted in polysaccharide mixtures. On the basis of sugar and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy data, it was concluded that both bacteria possess the same two distinct polysaccharides having structures 1 and 2: [structure: see text]. Structure 1 has been reported earlier for a polysaccharide of A. brasilense 54 [Fedonenko et al., 2011] whereas to our knowledge structure 2 has not been hitherto found in bacterial polysaccharides. Copyright © 2014 Elsevier Ltd. All rights reserved.

Isolation, identification and characterization of lignin-degrading bacteria from Qinling, China.

Science.gov (United States)

Yang, C-X; Wang, T; Gao, L-N; Yin, H-J; Lü, X

2017-12-01

Lignin is an aromatic heteropolymer forming a physical barrier and it is a big challenge in biomass utilization. This paper first investigated lignin-degradation bacteria from rotten wood in Qinling Mountain. Nineteen potential strains were selected and ligninolytic enzyme activities were determined over 84 h. Strains that had higher enzyme activities were selected. Further, the biodegradation of wheat straw lignin and alkali lignin was evaluated indicating that Burkholderia sp. H1 had the highest capability. It was confirmed by gel permeation chromatography and field emission scanning electron microscope that alkali lignin was depolymerized into small fragments. The degraded products were analysed using gas chromatography-mass spectrometry. The total ion chromatograph of products treated for 7 days showed the formation of aromatic compounds, an important intermediate from lignin degradation. Interestingly, they disappeared in 15 days while the aldehyde and ester compounds increased. The results suggest that the lignin-degrading bacteria are abundant in rotten wood and strain H1 has high potential to break down lignin. The diversity of lignin-degrading bacteria in Qinling Mountain is revealed. The study of Burkholderia sp. H1 expands the range of bacteria for lignin degradation and provides novel bacteria for application to lignocellulosic biomass. © 2017 The Society for Applied Microbiology.

Isolation and characterization of diuron-degrading bacteria from lotic surface water.

Science.gov (United States)

Batisson, Isabelle; Pesce, Stéphane; Besse-Hoggan, Pascale; Sancelme, Martine; Bohatier, Jacques

2007-11-01

The bacterial community structure of a diuron-degrading enrichment culture from lotic surface water samples was analyzed and the diuron-degrading strains were selected using a series of techniques combining temporal temperature gradient gel electrophoresis (TTGE) of 16 S rDNA gene V1-V3 variable regions, isolation of strains on agar plates, colony hybridization methods, and biodegradation assays. The TTGE fingerprints revealed that diuron had a strong impact on bacterial community structure and highlighted both diuron-sensitive and diuron-adapted bacterial strains. Two bacterial strains, designated IB78 and IB93 and identified as belonging to Pseudomonas sp. and Stenotrophomonas sp., were isolated and shown to degrade diuron in pure resting cells in a first-order kinetic reaction during the first 24 h of incubation with no 3,4-DCA detected. The percentages of degradation varied from 25% to 60% for IB78 and 20% to 65% for IB93 and for a diuron concentration range from 20 mg/L to 2 mg/L, respectively. It is interesting to note that diuron was less degraded by single isolates than by mixed resting cells, thereby underlining a cumulative effect between these two strains. To the best of our knowledge, this is the first report of diuron-degrading strains isolated from lotic surface water.

Degradation of lignocelluloses in rice straw by BMC-9, a composite microbial system.

Science.gov (United States)

Zhao, Hongyan; Yu, Hairu; Yuan, Xufeng; Piao, Renzhe; Li, Hulin; Wang, Xiaofen; Cui, Zongjun

2014-05-01

To evaluate the potential utility of pretreatment of raw biomass with a complex microbial system, we investigated the degradation of rice straw by BMC-9, a lignocellulose decomposition strain obtained from a biogas slurry compost environment. The degradation characteristics and corresponding changes in the bacterial community were assessed. The results showed that rapid degradation occurred from day 0 to day 9, with a peak total biomass bacterium concentration of 3.3 × 10(8) copies/ml on day 1. The pH of the fermentation broth declined initially and then increased, and the mass of rice straw decreased steadily. The highest concentrations of volatile fatty acid contents (0.291 mg/l lactic acid, 0.31 mg/l formic acid, 1.93 mg/l acetic acid, and 0.73 mg/l propionic acid) as well as the highest xylanse activity (1.79 U/ml) and carboxymethyl cellulase activity (0.37 U/ml) occurred on day 9. The greatest diversity among the microbial community also occurred on day 9, with the presence of bacteria belonging to Clostridium sp., Bacillus sp., and Geobacillus sp. Together, our results indicate that BMC-9 has a strong ability to rapidly degrade the lignocelluloses of rice straw under relatively inexpensive conditions, and the optimum fermentation time is 9 days.

Benzoate-mediated changes on expression profile of soluble proteins in Serratia sp. DS001.

Science.gov (United States)

Pandeeti, E V P; Chinnaboina, M R; Siddavattam, D

2009-05-01

To assess differences in protein expression profile associated with shift in carbon source from succinate to benzoate in Serratia sp. DS001 using a proteomics approach. A basic proteome map was generated for the soluble proteins extracted from Serratia sp. DS001 grown in succinate and benzoate. The differently and differentially expressed proteins were identified using ImageMaster 2D Platinum software (GE Healthcare). The identity of the proteins was determined by employing MS or MS/MS. Important enzymes such as Catechol 1,2 dioxygenase and transcriptional regulators that belong to the LysR superfamily were identified. Nearly 70 proteins were found to be differentially expressed when benzoate was used as carbon source. Based on the protein identity and degradation products generated from benzoate it is found that ortho pathway is operational in Serratia sp. DS001. Expression profile of the soluble proteins associated with shift in carbon source was mapped. The study also elucidates degradation pathway of benzoate in Serratia sp. DS001 by correlating the proteomics data with the catabolites of benzoate.

Biodegradation of 3,5-dimethyl-2,4-dichlorophenol in saline wastewater by newly isolated Penicillium sp. yz11-22N2.

Science.gov (United States)

Yan, Zhou; He, Huijun; Yang, Chunping; Zeng, Guangming; Luo, Le; Jiao, Panpan; Li, Huiru; Lu, Li

2017-07-01

In this study, the performance of 3,5-dimethyl-2,4-dichlorophenol (DCMX) degradation by a screened strain was investigated. 18S rDNA and the neighbor-joining method were used for identification of the isolated strain. The results of phylogenetic analysis and scanning electron micrographs showed that the most probable identity of the screened strain should be Penicillium sp. Growth characteristics of Penicillium sp. and degradation processes of DCMX were examined. Fourier transform infrared spectroscopy of the inoculated DCMX solution was recorded, which supported the capacity of DCMX degradation by the screened Penicillium sp. Under different salinity conditions, the highest growth rate and removal efficiency for DCMX were obtained at pH6.0. The removal efficiency decreased from 100% to 66% when the DCMX concentration increased from 5 to 60mg/L, respectively. Using a Box-Behnken design, the maximum DCMX removal efficiency was determined to be 98.4%. With acclimation to salinity, higher removal efficiency could be achieved. The results demonstrate that the screened Penicillium sp. has the capability for degradation of DCMX. Copyright © 2017. Published by Elsevier B.V.

Draft genome sequences of six neonatal meningitis-causing escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65)

Science.gov (United States)

Neonatal meningitis Escherichia coli isolates (SP-4, SP-5, SP-13, SP-16, SP-46, and SP-65) were recovered from infants in the Netherlands from 1989 to 1997. Here, we report the draft genome sequences for these six E. coli isolates, which are currently being used to validate food safety processing te...

Identification and genetic characterization of phenol- degrading ...

African Journals Online (AJOL)

SAURABH

2013-02-20

Feb 20, 2013 ... this paper, we reported about the new strain of Acinetobacter sp. ... characteristics of an efficient phenol-degrading microorganism. ... compounds are widespread in the environment. The problem is compounded by the fact that phenol is toxic, ... The phenol biodegradation ability of this bacterium was.

Mineralization of a Malaysian crude oil by Pseudomonas sp. and Achromabacter sp. isolated from coastal waters

Energy Technology Data Exchange (ETDEWEB)

Ahmad, J.; Ahmad, M.F.

1995-12-31

Regarded as being a potentially effective tool to combat oil pollution, bioremediation involves mineralization, i.e., the conversion of complex hydrocarbons into harmless CO{sub 2} and water by action of microorganisms. Therefore, in achieving optimum effectiveness from the application of these products on crude oil in local environments, the capability of the bacteria to mineralize hydrocarbons was evaluated. The microbial laboratory testing of mineralization on local oil degraders involved, first, isolation of bacteria found at a port located on the west coast of Peninsular Malaysia. Subsequently, these bacteria were identified by means of Biomereux`s API 20E and 20 NE systems and later screened by their growth on a Malaysian crude oil. Selected strains of Pseudomonas sp. and Achromabacter sp. were then exposed individually to a similar crude oil in a mineralization unit and monitored for 16 days for release of CO{sub 2}. Pseudomonas paucimobilis was found to produce more CO{sub 2} than Achromobacter sp. When tested under similar conditions, mixed populations of these two taxa produced more CO{sub 2} than that produced by any individual strain. Effective bioremediation of local crude in Malaysian waters can therefore be achieved from biochemically developed Pseudomonas sp. strains.

Identification of three homologous latex-clearing protein (lcp) genes from the genome of Streptomyces sp. strain CFMR 7.

Science.gov (United States)

Nanthini, Jayaram; Ong, Su Yean; Sudesh, Kumar

2017-09-10

Rubber materials have greatly contributed to human civilization. However, being a polymeric material does not decompose easily, it has caused huge environmental problems. On the other hand, only few bacteria are known to degrade rubber, with studies pertaining them being intensively focusing on the mechanism involved in microbial rubber degradation. The Streptomyces sp. strain CFMR 7, which was previously confirmed to possess rubber-degrading ability, was subjected to whole genome sequencing using the single molecule sequencing technology of the PacBio® RS II system. The genome was further analyzed and compared with previously reported rubber-degrading bacteria in order to identify the potential genes involved in rubber degradation. This led to the interesting discovery of three homologues of latex-clearing protein (Lcp) on the chromosome of this strain, which are probably responsible for rubber degrading activities. Genes encoding oxidoreductase α-subunit (oxiA) and oxidoreductase β-subunit (oxiB) were also found downstream of two lcp genes which are located adjacent to each other. In silico analysis reveals genes that have been identified to be involved in the microbial degradation of rubber in the Streptomyces sp. strain CFMR 7. This is the first whole genome sequence of a clear-zone-forming natural rubber- degrading Streptomyces sp., which harbours three Lcp homologous genes with the presence of oxiA and oxiB genes compared to the previously reported Gordonia polyisoprenivorans strain VH2 (with two Lcp homologous genes) and Nocardia nova SH22a (with only one Lcp gene). Copyright © 2017 Elsevier B.V. All rights reserved.

Effective pesticide nano formulations and their bacterial degradation

Science.gov (United States)

Ramadass, M.; Thiagarajan, P.

2017-11-01

The use of chemical pesticides for agricultural pest control and the consequent damage to the ecosystem at air, water and soil levels has become a factor of common knowledge. This alarming trend has led to research and development in the area of nanoformulations to achieve the end use of pest control with very low concentrations of pesticides. Such formulations are being proven to be as effective as traditional formulations due to their inherent ability to achieve controlled delivery of their respective active ingredients. The end result is a successful pest control with minimum environmental damage. Despite this, certain organic groups, that form the essential structural constituents of these pesticides, are not readily degraded due to their complex nature. They continue to persist, accumulate and biomagnify in the environment leading to short and long term hazards. In this context, it has been noted that certain common genera of bacteria such as Bacillus, Pseudomonas, Flavobacterium, Sphingomonas, Brevibacterium, Burkholderia, etc possess the inherent ability to utilise specific chemical groups in the pesticides as their sole source of either carbon and / or nitrogen and consequently achieve their conversion into non-toxic end products. A potential bioremediation process is thus slowly gaining popularity and being implemented on a pilot scale. However, large scale successful pesticide microbial remediation will involve experimentation with several combinations of a variety of nano pesticide formulations with different genera of bacteria under optimised conditions. Such studies will throw light on the precise genus and species of bacteria that may degrade the required groups of pesticides, for environmental damage control in the long run.

Halococcus agarilyticus sp. nov., an agar-degrading haloarchaeon isolated from commercial salt.

Science.gov (United States)

Minegishi, Hiroaki; Echigo, Akinobu; Shimane, Yasuhiro; Kamekura, Masahiro; Itoh, Takashi; Ohkuma, Moriya; Usami, Ron

2015-05-01

Two agar-degrading halophilic archaeal strains, 62 E(T) and 197 A, were isolated from commercial salt samples. Cells were non-motile cocci, approximately 1.2-2.0 µm in diameter and stained Gram-negative. Colonies were pink-pigmented. Strain 62 E(T) was able to grow with 24-30% (w/v) NaCl (optimum, 27%), at pH 6.5-8.5 (optimum, pH 7.5) and at 22-47 °C (optimum, 42 °C). The 16S rRNA gene sequences of strains 62 E(T) and 197 A were identical, and the level of DNA-DNA relatedness between them was 90 and 90% (reciprocally). The closest relative was Halococcus saccharolyticus JCM 8878(T) with 99.7% similarity in 16S rRNA orthologous gene sequences, followed by Halococcus salifodinae JCM 9578(T) (99.6%), while similarities with other species of the genus Halococcus were equal to or lower than 95.1%. The rpoB' gene tree strongly supported that the two strains were members of the genus Halococcus . Mean DNA-DNA relatedness between strain 62 E(T) and H. saccharolyticus JCM 8878(T) and H. salifodinae JCM 9578(T) was 46 and 44%, respectively. The major polar lipids were archaeol derivatives of phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, derived from both C20C20 and C20C25 archaeol, and sulfated diglycosyl archaeol-1. Several unidentified glycolipids were present. Based on the phenotypic and phylogenetic analyses, the isolates are considered to represent a novel species of the genus Halococcus , for which the name Halococcus agarilyticus sp. nov. is proposed. The type strain is 62 E(T) ( = JCM 19592(T) =KCTC 4143(T)). © 2015 IUMS.

Cellulase production by thermophilic Bacillus sp. SMIA-2 and its detergent compatibility

Directory of Open Access Journals (Sweden)

Silvania A. Ladeira

2015-03-01

Conclusions: The properties presented by Bacillus sp. SMIA-2 suggest that this organism might become a potential source of lignocellulose-degrading enzymes for industrial applications such as in the detergent industry.

Network structure and functional properties of transparent hydrogel sanxan produced by Sphingomonas sanxanigenens NX02.

Science.gov (United States)

Wu, Mengmeng; Shi, Zhong; Huang, Haidong; Qu, Jianmei; Dai, Xiaohui; Tian, Xuefeng; Wei, Weiying; Li, Guoqiang; Ma, Ting

2017-11-15

The micro-network structure and functional properties of sanxan, a novel polysaccharide produced by Sphingomonas sanxanigenens NX02, were investigated. Transparent hydrogel sanxan was a high acyl polymer containing 8.96% acetyl and 4.75% glyceroyl. The micro-network structure of sanxan was mainly cyclic configurations composed of side-by-side intermolecular associations, with many rounded nodes found. Sanxan exhibited predominant gelation behavior at concentrations above 0.1%, which was enhanced by adding cations, especially Ca 2+ . The gel strength of sanxan was much higher than that of low acyl gellan, but slightly lower than that of high acyl gellan. Furthermore, the conformation transition temperature was increased in the presence of added cations. Moreover, sanxan showed excellent emulsifying and emulsion stabilizing properties. Consequently, such excellent functional properties make sanxan a good candidate as a gelling, stabilizing, emulsifying, or suspending agent in food and cosmetics industries, and in medical and pharmaceutical usage. Copyright © 2017 Elsevier Ltd. All rights reserved.

Produksi, isolasi dan karakterisasi enzim dekstranase dari Arthrobacter sp. B7

Directory of Open Access Journals (Sweden)

Afaf Baktir

2012-02-01

Full Text Available Dextranase enzyme has been purified and characterized from Arthrobacter sp. B7. This enzyme was purified from the culture supernatant of Arthrobacter sp. B7 by procedure of native PAGE. The molecular size of the enzyme was estimated 72,5 kDa by SDSPAGE. The N-terminal amino acid sequence of this enzyme determined using Edman degradation techniques were APVTADVGNLHT. SDS-PAGE and native-PAGE analysis revealed that the enzyme molecule consisted of one sub-unit.

The quantitative significance of Syntrophaceae and syntrophic partnerships in methanogenic degradation of crude oil alkanes.

Science.gov (United States)

Gray, N D; Sherry, A; Grant, R J; Rowan, A K; Hubert, C R J; Callbeck, C M; Aitken, C M; Jones, D M; Adams, J J; Larter, S R; Head, I M

2011-11-01

Libraries of 16S rRNA genes cloned from methanogenic oil degrading microcosms amended with North Sea crude oil and inoculated with estuarine sediment indicated that bacteria from the genera Smithella (Deltaproteobacteria, Syntrophaceace) and Marinobacter sp. (Gammaproteobacteria) were enriched during degradation. Growth yields and doubling times (36 days for both Smithella and Marinobacter) were determined using qPCR and quantitative data on alkanes, which were the predominant hydrocarbons degraded. The growth yield of the Smithella sp. [0.020 g(cell-C)/g(alkane-C)], assuming it utilized all alkanes removed was consistent with yields of bacteria that degrade hydrocarbons and other organic compounds in methanogenic consortia. Over 450 days of incubation predominance and exponential growth of Smithella was coincident with alkane removal and exponential accumulation of methane. This growth is consistent with Smithella's occurrence in near surface anoxic hydrocarbon degrading systems and their complete oxidation of crude oil alkanes to acetate and/or hydrogen in syntrophic partnership with methanogens in such systems. The calculated growth yield of the Marinobacter sp., assuming it grew on alkanes, was [0.0005 g(cell-C)/g(alkane-C)] suggesting that it played a minor role in alkane degradation. The dominant methanogens were hydrogenotrophs (Methanocalculus spp. from the Methanomicrobiales). Enrichment of hydrogen-oxidizing methanogens relative to acetoclastic methanogens was consistent with syntrophic acetate oxidation measured in methanogenic crude oil degrading enrichment cultures. qPCR of the Methanomicrobiales indicated growth characteristics consistent with measured rates of methane production and growth in partnership with Smithella. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Effective enhancement of polylactic acid-degrading enzyme production by Amycolatopsis sp. strain SCM_MK2-4 using statistical and one-factor-at-a-time approaches.

Science.gov (United States)

Penkhrue, Watsana; Kanpiengjai, Apinun; Khanongnuch, Chartchai; Masaki, Kazuo; Pathom-Aree, Wasu; Punyodom, Winita; Lumyong, Saisamorn

2017-08-09

This study aims to find the optimal medium and conditions for polylactic acid (PLA)-degrading enzyme production by Amycolatopsis sp. SCM_MK2-4. Screening of the most effective components in the enzyme production medium by Plackett-Burman design revealed that the silk cocoon and PLA film were the most significant variables enhancing the PLA-degrading enzyme production. After an response surface methodology, a maximum amount of PLA-degrading enzyme activity at 0.74 U mL -1 was predicted and successfully validated at 95% after 0.39% (w/v) silk cocoon and 1.62% (w/v) PLA film were applied to the basal medium. The optimal initial pH value, temperature, and inoculum size were evaluated by a method considering one-factor-at-a-time. The values were recorded at an initial pH in the range of 7.5-9.0, a temperature of 30-32°C, and an inoculum size of 4-10%. The highest activity of approximately 0.95 U mL -1 was achieved after 4 days of cultivation using the optimized medium and under optimized conditions in a shake flask. Upscaling to the use of a 3-L stirred tank fermenter was found to be successful with a PLA-degrading activity of 5.53 U mL -1 ; which represents a 51-fold increase in the activity compared with that obtained from the nonoptimized medium and conditions in the shake flask.

Biosynthesis of gold nanoparticles by Aspergillum sp. WL-Au for degradation of aromatic pollutants

Science.gov (United States)

Qu, Yuanyuan; Pei, Xiaofang; Shen, Wenli; Zhang, Xuwang; Wang, Jingwei; Zhang, Zhaojing; Li, Shuzhen; You, Shengnan; Ma, Fang; Zhou, Jiti

2017-04-01

A simple method for synthesis of gold nanoparticles (AuNPs) using Aspergillum sp. WL-Au was presented in this study. According to UV-vis spectra and transmission electron microscopy images, the shape and size of AuNPs were affected by different parameters, including buffer solution, pH, biomass and HAuCl4 concentrations. Phosphate sodium buffer was more suitable for extracellular synthesis of AuNPs, and the optimal conditions for AuNPs synthesis were pH 7.0, biomass 100 mg/mL and HAuCl4 3 mM, leading to the production of spherical and pseudo-spherical nanoparticles. The biosynthesized AuNPs possessed excellent catalytic activities for the reduction of 2-nitrophenol, 3-nitrophenol, 4-nitrophenol, o-nitroaniline and m-nitroaniline in the presence of NaBH4, and the catalytic rate constants were calculated to be 6.3×10-3 s-1, 5.5×10-3 s-1, 10.6×10-3 s-1, 8.4×10-3 s-1 and 13.8×10-3 s-1, respectively. The AuNPs were also able to catalyze the decolorization of various azo dyes (e.g. Cationic Red X-GRL, Acid Orange II and Acid scarlet GR) using NaBH4 as the reductant, and the decolorization rates reached 91.0-96.4% within 7 min. The present study should provide a potential candidate for green synthesis of AuNPs, which could serve as efficient catalysts for aromatic pollutants degradation.

Effect of actinobacteria agent inoculation methods on cellulose degradation during composting based on redundancy analysis.

Science.gov (United States)

Zhao, Yue; Lu, Qian; Wei, Yuquan; Cui, Hongyang; Zhang, Xu; Wang, Xueqin; Shan, Si; Wei, Zimin

2016-11-01

In this study, actinobacteria agent including Streptomyces sp. and Micromonospora sp. were inoculated during chicken manure composting by different inoculation methods. The effect of different treatments on cellulose degradation and the relationship between inoculants and indigenous actinobacteria were investigated during composting. The results showed that inoculation in different stages of composting all improved the actinobacteria community diversity particularly in the cooling stage of composting (M3). Moreover, inoculation could distinctly accelerate the degradation of organic matters (OM) especially celluloses. Redundancy analysis indicated that the correlation between indigenous actinobacteria and degradation of OM and cellulose were regulated by inoculants and there were significant differences between different inoculation methods. Furthermore, synergy between indigenous actinobacteria and inoculants for degradation of OM and cellulose in M3 was better than other treatments. Conclusively, we suggested an inoculation method to regulate the indigenous actinobacteria based on the relationship between inoculants and indigenous actinobacteria and degradation content. Copyright © 2016 Elsevier Ltd. All rights reserved.

Preparation of Novel Fused Ring Spiro[benzotetraphene-fluorene] Derivatives and Application for Deep-Blue Host Materials

Energy Technology Data Exchange (ETDEWEB)

Kim, Minji; Lee, Chilwon; Gong, Myoungseon [Dankook Univ., Yongin (Korea, Republic of)

2014-06-15

A series of novel fused-ring spiro compounds, spiro[benzo[ij]tetraphene-7,9'-fluorene] derivatives containing an end-capping aryl substituent at both the C3 and C10-positions has been designed and synthesized via multi-step Suzuki coupling reactions. 3-(1-Naphthyl)-10-phenyl, 3-(2-naphthyl)-10-phenyl and 3-[4-(1-naphthyl)phenyl]-10-phenyl showed improved glass transition temperatures (T{sub g}) with good thermal stability. Their photophysical, electrochemical, and electroluminescent properties were investigated and were used to construct blue organic light emission diodes (OLEDs). The typical OLED devices showed excellent performance; the based device exhibited highly efficient deep blue-light emission with a maximum efficiency of 5.27 cd/A (EQE, 4.63%) with CIE (x = 0.133, y = 0.144). According to these characteristics, these deep-blue light emitting materials have sufficient potential for fluorescent OLED applications.

Two new nontoxic, non-pathogenic strains of Sphingomonas elodea for gellan gum production.

Science.gov (United States)

Dolan, Laurie C; Matulka, Ray A; LeBeau, Alex L; Boulet, Jamie M

2016-07-01

Two new strains of Sphingomonas elodea (designated as PHP1 and PBAD1) were tested for toxicity and pathogenicity in healthy Sprague-Dawley CD(®) IGS rats in separate studies. In each study, twelve rats/sex were administered ≥10(8) viable cells/rat by oral gavage, and four untreated rats/sex served as controls. Blood, feces, and selected organs/tissues collected at various times over the course of the 22 day study were evaluated for the presence of PHP1 or PBAD1 (depending on the study) by a validated method, to determine the potential for survival, propagation, or infectivity of PHP1 and PBAD1 cells in the rat. No mortalities, test substance-related changes in clinical or macroscopic findings, body weight or body weight gain were observed in treated animals compared with controls, indicating a lack of toxicity. PHP1 or PBAD1 were not detected in the tissue, fecal or fluid samples collected from treated animals. Therefore, neither PHP1 nor PBAD1 were pathogenic or acutely toxic under the conditions of the studies. Copyright © 2016. Published by Elsevier Inc.

The polycyclic aromatic hydrocarbon degradation potential of Gulf of Mexico coastal microbial communities after the Deepwater Horizon oil spill

Directory of Open Access Journals (Sweden)

Anthony D. Kappell

2014-05-01

Full Text Available The Deepwater Horizon (DWH blowout resulted in oil transport, including polycyclic aromatic hydrocarbons (PAHs to the Gulf of Mexico shoreline. The microbial communities of these shorelines are thought to be responsible for the intrinsic degradation of PAHs. To investigate the Gulf Coast beach microbial community response to hydrocarbon exposure, we examined the functional gene diversity, bacterial community composition, and PAH degradation capacity of a heavily oiled and non-oiled beach following the oil exposure. With a non-expression functional gene microarray targeting 539 gene families, we detected 28,748 coding sequences. Of these sequences, 10% were uniquely associated with the severely oil-contaminated beach and 6.0% with the non-oiled beach. There was little variation in the functional genes detected between the two beaches; however the relative abundance of functional genes involved in oil degradation pathways, including PAHs, were greater in the oiled beach. The microbial PAH degradation potentials of both beaches, were tested in mesocosms. Mesocosms were constructed in glass columns using sands with native microbial communities, circulated with artificial sea water and challenged with a mixture of PAHs. The low-molecular weight PAHs, fluorene and naphthalene, showed rapid depletion in all mesocosms while the high-molecular weight benzo[α]pyrene was not degraded by either microbial community. Both the heavily oiled and the non-impacted coastal communities showed little variation in their biodegradation ability for low molecular weight PAHs. Massively-parallel sequencing of 16S rRNA genes from mesocosm DNA showed that known PAH degraders and genera frequently associated with oil hydrocarbon degradation represented a major portion of the bacterial community. The observed similar response by microbial communities from beaches with a different recent history of oil exposure suggests that Gulf Coast beach communities are primed for PAH

Accumulation of metabolites during bacterial degradation of PAH-mixtures

Energy Technology Data Exchange (ETDEWEB)

Vila, J.; Lopez, Z.; Bauza, J.I. [Universitat de Barcelona (Spain). Department de Microbiologia; Minguillon, C. [Parc Cientific de Barcelona (ES). Institut de Recerca de Barcelona (IRB-PCB); Grifoll, M.

2003-07-01

In a previous work we identified a number of metabolites accumulated during growth in pyrene by Mycobacterium sp. AP1, and proposed a metabolic pathway for pyrene utilization. In order to confirm and complete this pathway we have isolated and identified the pyrene-degrading strains Mycobacterium sp. PGP2, CP1 and CP2. During growth on pyrene, strains AP1, PGP2, CP1 and CP2 accumulated 4,5-cis-pyrene-dihydrodiol, 4,5-phenanthrene dicarboxylic acid, 4-phenanthrene carboxylic acid, 3,4-dihydroxy-3-hydrophenanthrene-4-carboxylic acid, phthalic acid, and 6,6'-dihydroxy-2,2'-biphenyl dicarboxylic acid. Strains AP1, PGP2, CP1 and CP2 also grew on fluoranthene accumulating acenaphthenone, naphthalene-1,8-dicarboxylic acid, 9-fluorenone-1-carboxylic acid, Z-9-carboxymethylenefluorene-1-carboxylic acid and benzene-1,2,3-tricarboxylic acid. Similar metabolites were produced during growth onf fluoranthene by the Gram-positive strains CFt2 and CFt6, isolated by their capability of using this PAH as a sole source of carbon and energy. These fluoranthene-degrading strains also accumulated cis-1,9a-dihydroxy-1-hydrofluorene-9-one-8-carboxylic acid. In addition to pyrene and fluoranthene, all pyrene-degrading utilized phenanthrene as a sole source of carbon and energy, while the fluoranthene-degrading strains were unable to utilize pyrene or phenanthrene. Mycobacterium sp. AP1 acted on a wide range of PAHs, accumulating aromatic dicarboxylic acids, hydroxyacids, and ketones resulting from dioxygenation and ortho-cleavage, dioxygenation and meta-cleavage, and monooxygenation reactions. In cultures of strains AP1 and CP1 with a defined PAH-mixture only 20% removal of the parent compounds was observed. Analysis of acidic extracts showed the accumulation of the anticipated aromatic acids, suggesting that accumulation of acidic compounds could prevent further degradation of the mixture. Those results led us to isolation of strains DF11 and OH3, able to grow on the selected

Evaluation of microbially-influenced degradation of massive concrete structures

International Nuclear Information System (INIS)

Hamilton, M.A.; Rogers, R.D.; Zolynski, M.; Veeh, R.

1996-01-01

Many low level waste disposal vaults, both above and below ground, are constructed of concrete. One potential contributing agent to the destruction of concrete structures is microbially-influenced degradation (MID). Three groups of bacteria are known to create conditions that are conducive to destroying concrete integrity. They are sulfur oxidizing bacteria, nitrifying bacteria, and heterotrophic bacteria. Research is being conducted at the Idaho National Engineering Laboratory to assess the extent of naturally occurring microbially influenced degradation (MID) and its contribution to the deterioration of massive concrete structures. The preliminary steps to understanding the extent of MID, require assessing the microbial communities present on degrading concrete surfaces. Ultimately such information can be used to develop guidelines for preventive or corrective treatments for MID and aid in formulation of new materials to resist corrosion. An environmental study was conducted to determine the presence and activity of potential MID bacteria on degrading concrete surfaces of massive concrete structures. Scanning electron microscopy detected bacteria on the surfaces of concrete structures such as bridges and dams, where corrosion was evident. Enumeration of sulfur oxidizing thiobacilli and nitrogen oxidizing Nitrosomonas sp. and Nitrobacter sp. from surface samples was conducted. Bacterial community composition varied between sampling locations, and generally the presence of either sulfur oxidizers or nitrifiers dominated, although instances of both types of bacteria occurring together were encountered. No clear correlation between bacterial numbers and degree of degradation was exhibited

Microbial degradation of high impact polystyrene (HIPS), an e-plastic with decabromodiphenyl oxide and antimony trioxide

International Nuclear Information System (INIS)

Sekhar, Vini C.; Nampoothiri, K. Madhavan; Mohan, Arya J.; Nair, Nimisha R.; Bhaskar, Thallada; Pandey, Ashok

2016-01-01

Highlights: • Biodegradation of a high impact polystyrene e − plastic. • 12.4% (w/w) e plastic film lost using an isolate, Enterobacter sp. • Noted changes in the physico-chemical characteristics of degraded e-plastic film. • Polystyrene intermediates were detected in the degradation medium. • e-plastic degrading microbes displayed extracellular depolymerase activity. - Abstract: Accumulation of electronic waste has increased catastrophically and out of that various plastic resins constitute one of the leading thrown out materials in the electronic machinery. Enrichment medium, containing high impact polystyrene (HIPS) with decabromodiphenyl oxide and antimony trioxide as sole carbon source, was used to isolate microbial cultures. The viability of these cultures in the e-plastic containing mineral medium was further confirmed by triphenyl tetrazolium chloride (TTC) reduction test. Four cultures were identified by 16S rRNA sequencing as Enterobacter sp., Citrobacter sedlakii, Alcaligenes sp. and Brevundimonas diminuta. Biodegradation experiments were carried out in flask level and gelatin supplementation (0.1% w/v) along with HIPS had increased the degradation rate to a maximum of 12.4% (w/w) within 30 days. This is the first report for this kind of material. The comparison of FTIR, NMR, and TGA analysis of original and degraded e-plastic films revealed structural changes under microbial treatment. Polystyrene degradation intermediates in the culture supernatant were also detected using HPLC analysis. The gravity of biodegradation was validated by morphological changes under scanning electron microscope. All isolates displayed depolymerase activity to substantiate enzymatic degradation of e-plastic.

Microbial degradation of high impact polystyrene (HIPS), an e-plastic with decabromodiphenyl oxide and antimony trioxide

Energy Technology Data Exchange (ETDEWEB)

Sekhar, Vini C. [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India); Nampoothiri, K. Madhavan, E-mail: madhavan85@hotmail.com [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India); Mohan, Arya J.; Nair, Nimisha R. [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India); Bhaskar, Thallada [Bio-Fuels Division (BFD), CSIR-Indian Institute of Petroleum (IIP), Dehradun, Uttarakhand 248005 (India); Pandey, Ashok [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India)

2016-11-15

Highlights: • Biodegradation of a high impact polystyrene e − plastic. • 12.4% (w/w) e plastic film lost using an isolate, Enterobacter sp. • Noted changes in the physico-chemical characteristics of degraded e-plastic film. • Polystyrene intermediates were detected in the degradation medium. • e-plastic degrading microbes displayed extracellular depolymerase activity. - Abstract: Accumulation of electronic waste has increased catastrophically and out of that various plastic resins constitute one of the leading thrown out materials in the electronic machinery. Enrichment medium, containing high impact polystyrene (HIPS) with decabromodiphenyl oxide and antimony trioxide as sole carbon source, was used to isolate microbial cultures. The viability of these cultures in the e-plastic containing mineral medium was further confirmed by triphenyl tetrazolium chloride (TTC) reduction test. Four cultures were identified by 16S rRNA sequencing as Enterobacter sp., Citrobacter sedlakii, Alcaligenes sp. and Brevundimonas diminuta. Biodegradation experiments were carried out in flask level and gelatin supplementation (0.1% w/v) along with HIPS had increased the degradation rate to a maximum of 12.4% (w/w) within 30 days. This is the first report for this kind of material. The comparison of FTIR, NMR, and TGA analysis of original and degraded e-plastic films revealed structural changes under microbial treatment. Polystyrene degradation intermediates in the culture supernatant were also detected using HPLC analysis. The gravity of biodegradation was validated by morphological changes under scanning electron microscope. All isolates displayed depolymerase activity to substantiate enzymatic degradation of e-plastic.

Removal Capacities of Polycyclic Aromatic Hydrocarbons (PAHs by a Newly Isolated Strain from Oilfield Produced Water

Directory of Open Access Journals (Sweden)

Yi-Bin Qi

2017-02-01

Full Text Available The polycyclic aromatic hydrocarbon (PAH-degrading strain Q8 was isolated from oilfield produced water. According to the analysis of a biochemical test, 16S rRNA gene, house-keeping genes and DNA–DNA hybridization, strain Q8 was assigned to a novel species of the genus Gordonia. The strain could not only grow in mineral salt medium (MM and utilize naphthalene and pyrene as its sole carbon source, but also degraded mixed naphthalene, phenanthrene, anthracene and pyrene. The degradation ratio of these four PAHs reached 100%, 95.4%, 73.8% and 53.4% respectively after being degraded by Q8 for seven days. A comparative experiment found that the PAHs degradation efficiency of Q8 is higher than that of Gordonia alkaliphila and Gordonia paraffinivorans, which have the capacities to remove PAHs. Fourier transform infrared spectra, saturate, aromatic, resin and asphaltene (SARA and gas chromatography–mass spectrometry (GC–MS analysis of crude oil degraded by Q8 were also studied. The results showed that Q8 could utilize n-alkanes and PAHs in crude oil. The relative proportions of the naphthalene series, phenanthrene series, thiophene series, fluorene series, chrysene series, C21-triaromatic steroid, pyrene, and benz(apyrene were reduced after being degraded by Q8. Gordonia sp. nov. Q8 had the capacity to remediate water and soil environments contaminated by PAHs or crude oil, and provided a feasible way for the bioremediation of PAHs and oil pollution.

Production of raw starch-degrading enzyme by Aspergillus sp. and its use in conversion of inedible wild cassava flour to bioethanol.

Science.gov (United States)

Moshi, Anselm P; Hosea, Ken M M; Elisante, Emrode; Mamo, Gashaw; Önnby, Linda; Nges, Ivo Achu

2016-04-01

The major bottlenecks in achieving competitive bioethanol fuel are the high cost of feedstock, energy and enzymes employed in pretreatment prior to fermentation. Lignocellulosic biomass has been proposed as an alternative feedstock, but because of its complexity, economic viability is yet to be realized. Therefore, research around non-conventional feedstocks and deployment of bioconversion approaches that downsize the cost of energy and enzymes is justified. In this study, a non-conventional feedstock, inedible wild cassava was used for bioethanol production. Bioconversion of raw starch from the wild cassava to bioethanol at low temperature was investigated using both a co-culture of Aspergillus sp. and Saccharomyces cerevisiae, and a monoculture of the later with enzyme preparation from the former. A newly isolated strain of Aspergillus sp. MZA-3 produced raw starch-degrading enzyme which displayed highest activity of 3.3 U/mL towards raw starch from wild cassava at 50°C, pH 5.5. A co-culture of MZA-3 and S. cerevisiae; and a monoculture of S. cerevisiae and MZA-3 enzyme (both supplemented with glucoamylase) resulted into bioethanol yield (percentage of the theoretical yield) of 91 and 95 at efficiency (percentage) of 84 and 96, respectively. Direct bioconversion of raw starch to bioethanol was achieved at 30°C through the co-culture approach. This could be attractive since it may significantly downsize energy expenses. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Degradative capacities and bioaugmentation potential of an anaerobic benzene-degrading bacterium strain DN11

Energy Technology Data Exchange (ETDEWEB)

Yuki Kasai; Yumiko Kodama; Yoh Takahata; Toshihiro Hoaki; Kazuya Watanabe [Marine Biotechnology Institute, Kamaishi (Japan)

2007-09-15

Azoarcus sp. strain DN11 is a denitrifying bacterium capable of benzene degradation under anaerobic conditions. The present study evaluated strain DN11 for its application to bioaugmentation of benzene-contaminated underground aquifers. Strain DN11 could grow on benzene, toluene, m-xylene, and benzoate as the sole carbon and energy sources under nitrate-reducing conditions, although o- and p-xylenes were transformed in the presence of toluene. Phenol was not utilized under anaerobic conditions. Kinetic analysis of anaerobic benzene degradation estimated its apparent affinity and inhibition constants to be 0.82 and 11 {mu}M, respectively. Benzene-contaminated groundwater taken from a former coal-distillation plant site in Aichi, Japan was anaerobically incubated in laboratory bottles and supplemented with either inorganic nutrients (nitrogen, phosphorus, and nitrate) alone, or the nutrients plus strain DN11, showing that benzene was significantly degraded only when DN11 was introduced. Denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments, and quantitative PCR revealed that DN11 decreased after benzene was degraded. Following the decrease in DN11 16S rRNA gene fragments corresponding to bacteria related to Owenweeksia hongkongensis and Pelotomaculum isophthalicum, appeared as strong bands, suggesting possible metabolic interactions in anaerobic benzene degradation. Results suggest that DN11 is potentially useful for degrading benzene that contaminates underground aquifers at relatively low concentrations. 50 refs., 6 figs., 1 tab.

Biofilm-forming activity of bacteria isolated from toilet bowl biofilms and the bactericidal activity of disinfectants against the isolates.

Science.gov (United States)

Mori, Miho; Gomi, Mitsuhiro; Matsumune, Norihiko; Niizeki, Kazuma; Sakagami, Yoshikazu

2013-01-01

To evaluate the sanitary conditions of toilets, the bacterial counts of the toilet bowl biofilms in 5 Kansai area and 11 Kansai and Kanto area homes in Japan were measured in winter and summer seasons, respectively. Isolates (128 strains) were identified by analyzing 16S ribosomal RNA sequences. The number of colonies and bacterial species from biofilms sampled in winter tended to be higher and lower, respectively, than those in summer. Moreover, the composition of bacterial communities in summer and winter samples differed considerably. In summer samples, biofilms in Kansai and Kanto areas were dominated by Blastomonas sp. and Mycobacterium sp., respectively. Methylobacterium sp. was detected in all toilet bowl biofilms except for one sample. Methylobacterium sp. constituted the major presence in biofilms along with Brevundimonas sp., Sphingomonas sp., and/or Pseudomonas sp. The composition ratio of the sum of their genera was 88.0 from 42.9% of the total bacterial flora. The biofilm formation abilities of 128 isolates were investigated, and results suggested that Methylobacterium sp. and Sphingomonas sp. were involved in biofilm formation in toilet bowls. The biofilm formation of a mixed bacteria system that included bacteria with the highest biofilm-forming ability in a winter sample was greater than mixture without such bacteria. This result suggests that isolates possessing a high biofilm-forming activity are involved in the biofilm formation in the actual toilet bowl. A bactericidal test against 25 strains indicated that the bactericidal activities of didecyldimethylammonium chloride (DDAC) tended to be higher than those of polyhexamethylene biguanide (PHMB) and N-benzyl-N,N-dimethyldodecylammonium chloride (ADBAC). In particular, DDAC showed high bactericidal activity against approximately 90% of tested strains under the 5 h treatment.

Control of Branchionus sp. and Amoeba sp. in cultures of Arthrospira sp. Control de Branchionus sp. y Amoeba sp. en cultivos de Arthrospira sp.

Directory of Open Access Journals (Sweden)

Carlos Méndez

2012-09-01

Full Text Available Cultivation of cyanobacterium Arthrospira sp. has been developed in many countries for the production of proteins, pigments and other compounds. Outdoor mass cultures are often affected by biological contamination, drastically reducing productivity as far as bringing death. This study evaluates the control of Branchionus sp. and Amoeba sp. with two chemical compounds: urea (U and ammonium bicarbonate (AB, in laboratory conditions and outdoor mass culture of Arthrospira sp. The lethal concentration 100 (LC100 at 24 h for Branchionus sp. and Amoeba sp. determined was of 60-80 mg L-1 (U and 100-150 mg L-1 (AB. The average effective inhibition concentration for 50% of the population (IC50 in Arthrospira sp., after 72 h, was 80 mg L-1 (U and 150 mg L-1 (AB. The application of doses of 60 mg L-1 (U or 100 mg L-1 (AB in the outdoor mass culture of this contaminated microalga, completely inhibited grazing and did not affect the growth of Arthrospira sp. but rather promoted rapid recovery of algal density at levels prior to infestation. These compounds provided an economical and effective control of predators in cultures of Arthrospira sp.El cultivo de la cianobacteria Arthrospira sp. ha sido desarrollado en muchos países para la obtención de proteínas, pigmentos y otros compuestos. Cultivo que a nivel industrial se ve afectado frecuentemente por contaminación biológica, reduciendo drásticamente la productividad hasta causar la muerte. Este estudio evalúa el control de Branchionus sp. y de Amoeba sp. con dos compuestos químicos, la urea (U y bicarbonato de amonio (AB en cultivos de Arthrospira sp. La concentración letal 100 (LC100 determinada a las 24 h para Branchionus sp. y Amoeba sp. fue de 60-80 mg L-1 (U y 100-150 mg L-1 (AB. La concentración media de inhibición efectiva, después de 72 h, para el 50% de la población (IC50 en Arthrospira fue de 80 mg L-1 (U y 150 mg L-1 (AB. La aplicación de dosis de 60 mg L-1 (U ó 100 mg L-1 (AB en

Degradation of natural cellulose by thermophilic and thermotolerant fungi

Energy Technology Data Exchange (ETDEWEB)

Thakre, A P; Johri, B N

1981-06-01

Aspergillus fumigatus Friesen, Sporotrichum sp., Thermoascus aurantiacus Miche and Torula thermophila Cooney and Emerson were able to degrade filter paper to an appreciable extent. Absidia corymbifera (Cohn) Saccardo et Trotter, Rhizopus microsporus van Tieghem and R. rhizopodiformis (Cohn) Zopf could not degrade filter paper though they were able to grow on the media supplied. The fungi able to degrade filter paper were also capable of elaborating extracellular cellulase and produced sufficient hydrolysis of carboxymethyl cellulose. The Cx enzyme was stable at 45 degrees C for 25 days. An incubation period of 15 to 25 days was sufficient not only to degrade CMC but even more complex substrates, such as jute, cotton and filter paper. The cellulases of these fungi were inductive in nature. (Refs. 11).

Impacts of varying light regimes on phycobiliproteins of Nostoc sp. HKAR-2 and Nostoc sp. HKAR-11 isolated from diverse habitats.

Science.gov (United States)

Kannaujiya, Vinod K; Sinha, Rajeshwar P

2015-11-01

The adaptability of cyanobacteria in diverse habitats is an important factor to withstand harsh conditions. In the present investigation, the impacts of photosynthetically active radiation (PAR; 400-700 nm), ultraviolet-B (UV-B; 280-315 nm), and PAR + UV-B radiations on two cyanobacteria viz., Nostoc sp. HKAR-2 and Nostoc sp. HKAR-11 inhabiting diverse habitats such as hot springs and rice fields, respectively, were studied. Cell viability was about 14 % in Nostoc sp. HKAR-2 and Nostoc sp. HKAR-11 after 48 h of UV-B exposure. PAR had negligible negative impact on the survival of both cyanobacteria. The continuous exposure of UV-B and PAR + UV-B showed rapid uncoupling, bleaching, fragmentation, and degradation in both phycocyanin (C-PC) and phycoerythrin (C-PE) subunits of phycobiliproteins (PBPs). Remarkable bleaching effect of C-PE and C-PC was not only observed with UV-B or PAR + UV-B radiation, but longer period (24-48 h) of exposure with PAR alone also showed noticeable negative impact. The C-PE and C-PC subunits of the rice field isolate Nostoc sp. HKAR-11 were severely damaged in comparison to the hot spring isolate Nostoc sp. HKAR-2 with rapid wavelength shifting toward shorter wavelengths denoting the bleaching of both the accessory light harvesting pigments. The results indicate that PBPs of the hot spring isolate Nostoc sp. HKAR-2 were more stable under various light regimes in comparison to the rice field isolate Nostoc sp. HKAR-11 that could serve as a good source of valuable pigments to be used in various biomedical and biotechnological applications.

Co-metabolism of DDT by the newly isolated bacterium, Pseudoxanthomonas sp. wax

Directory of Open Access Journals (Sweden)

Guangli Wang

2010-06-01

Full Text Available Microbial degradation of 1,1,1-trichloro-2,2-bis(p-chlorophenylethane (DDT is the most promising way to clean up DDT residues found in the environment. In this paper, a bacterium designated as wax, which was capable of co-metabolizing DDT with other carbon sources, was isolated from a long-term DDT-contaminated soil sample by an enrichment culture technique. The new isolate was identified as a member of the Pseudoxanthomonas sp., based on its morphological, physiological and biochemical properties, as well as by 16S rRNA gene analysis. In the presence of 100 mg l-1 glucose, the wax strain could degrade over 95% of the total DDT, at a concentration of 20 mg l-1, in 72 hours, and could degrade over 60% of the total DDT, at a concentration of 100 mg l-1, in 144 hours. The wax strain had the highest degradation efficiency among all of the documented DDT-degrading bacteria. The wax strain could efficiently degrade DDT at temperatures ranging from 20 to 37ºC, and with initial pH values ranging from 7 to 9. The bacterium could also simultaneously co-metabolize 1,1-dichloro-2,2-bis(p-chlorophenylethane (DDD, 2,2-bis(p-chlorophenyl-1,1-dichlorethylene (DDE, and other organochlorine compounds. The wax strain could also completely remove 20 mg kg-1 of DDT from both sterile and non-sterile soils in 20 days. This study demonstrates the significant potential use of Pseudoxanthomonas sp. wax for the bioremediation of DDT in the environment.

Degradation of the Phosphonate Herbicide Glyphosate by Arthrobacter atrocyaneus ATCC 13752

OpenAIRE

Pipke, Rüdiger; Amrhein, Nikolaus

1988-01-01

Of nine authentic Arthrobacter strains tested, only A. atrocyaneus ATCC 13752 was capable of using the herbicide glyphosate [N-(phosphonomethyl)glycine] as its sole source of phosphorus. Contrary to the previously isolated Arthrobacter sp. strain GLP-1, which degrades glyphosate via sarcosine, A. atrocyaneus metabolized glyphosate to aminomethylphosphonic acid. The carbon of aminomethylphosphonic acid was entirely converted to CO2. This is the first report on glyphosate degradation by a bacte...

Polymer Film-Based Screening and Isolation of Polylactic Acid (PLA)-Degrading Microorganisms.

Science.gov (United States)

Kim, Mi Yeon; Kim, Changman; Moon, Jungheun; Heo, Jinhee; Jung, Sokhee P; Kim, Jung Rae

2017-02-28

Polylactic acid (PLA) has been highlighted as an alternative renewable polymer for the replacement of petroleum-based plastic materials, and is considered to be biodegradable. On the other hand, the biodegradation of PLA by terminal degraders, such as microorganisms, requires a lengthy period in the natural environment, and its mechanism is not completely understood. PLA biodegradation studies have been conducted using mainly undefined mixed cultures, but only a few bacterial strains have been isolated and examined. For further characterization of PLA biodegradation, in this study, the PLA-degrading bacteria from digester sludge were isolated and identified using a polymer film-based screening method. The enrichment of sludge on PLA granules was conducted with the serial transference of a subculture into fresh media for 40 days, and the attached biofilm was inoculated on a PLA film on an agar plate. 3D optical microscopy showed that the isolates physically degraded the PLA film due to bacterial degradation. 16S rRNA gene sequencing identified the microbial colonies to be Pseudomonas sp. MYK1 and Bacillus sp. MYK2. The two isolates exhibited significantly higher specific gas production rates from PLA biodegradation compared with that of the initial sludge inoculum.

Constitutive expression of Vitreoscilla haemoglobin in Sphingomonas elodea to improve gellan gum production.

Science.gov (United States)

Wu, X C; Chen, Y M; Li, Y D; Li, O; Zhu, L; Qian, C D; Tao, X L; Teng, Y

2011-02-01

To improve a commercially used strain for gellan production by exogenous Vitreoscilla haemoglobin (VHb). VHb gene was expressed in Sphingomonas elodea under the control of constitutive bla promoter. Biochemical activity of expressed VHb was confirmed by CO-difference spectra analysis that exhibited a characteristic absorption maximum at 419 nm. During cultivation, not only enhanced cell growth was detected, but also 20% improvement in gellan production was observed after 48 h of incubation, with a maximum yield of 16·82 g l(-1). Moreover, maximum sucrose conversion efficiency (g gellan per g sucrose) was 57·8, 20% higher than that of the parental strain. We further examined the polysaccharide production of VHb-expressing strain at different aeration levels in Erlenmeyer flasks. Again, in all cases, a significant enhancement of gellan production was observed, and the enhancement was more significant under oxygen-limiting conditions (up to 26·8%). VHb exhibited positive effect on cell growth and gellan yield of S. elodea, especially under hypoxic conditions. This is the first application of VHb as an effective metabolic engineering strategy in S. elodea to regulate cell growth and optimize gellan yield. © 2010 The Authors. Journal of Applied Microbiology © 2010 The Society for Applied Microbiology.

Seroprevalencia de Leptospira sp., Rickettsia sp. Ehrlichia sp. en trabajadores rurales del departamento de Sucre, Colombia Seroprevalence of Leptospira sp., Rickettsia sp. and Ehrlichia sp. in rural workers of Sucre, Colombia

Directory of Open Access Journals (Sweden)

Rodrigo Ríos

2008-06-01

Full Text Available Objective. Determinar la seroprevalencia de Leptospira sp., Rickettsia sp. y Ehrlichia sp. en trabajadores de áreas rurales del departamento de Sucre. Material y métodos. Se realizó un estudio escriptivo, prospectivo, de corte transversal, que pretendió determinar la seroprevalencia e Leptospira sp., Rickettsia sp. y Ehrlichia sp. en 90 trabajadores de áreas rurales del departamento de Sucre. Se estableció la presencia de anticuerpos séricos anti-IgM específicos anti-Leptospira por la técnica de ELISA indirecta. Para la determinación de Rickettsia sp. y Ehrlichia sp. se uso la técnica de inmunofluorescencia indirecta. Resultados. La población evaluada estaba compuesta por 27 (30% ordeñadores, 21 (23% jornaleros, 18 (20% profesionales del campo y 24 (27% que realizaban otras actividades. Ventidós (24% muestras resultaron positivas en alguna de las pruebas. De éstas, 12 (13,3% fueron positivas para Leptospira sp., 7 (7,8% para Rickettsia sp. y 3 (3,3% ara Ehrlichia sp. Conclusión. Este fue el primer estudio que se llevó a cabo en el departamento de Sucre y permitió demostrar que existe una prevalencia importante de Leptospira p.,Rickettsia sp. y Ehrlichia sp.. Los factores de riesgo ocupacional fueron factores determinantes en la seropositividad.Objective. To determine the seroprevalence of Leptospira sp., Rickettsia sp. and Ehrlichia sp. in agricultural workers of Sucre. Methods. A descriptive prospective cross-sectional study was conducted in ninety rural workers of Sucre. Presence of serum antibodies anti-IgM specific anti-Leptospira by indirect ELISA was established. For the determination of Rickettsia and Ehrlichia indirect inmunoflorescence was used. Results.The population was composed by 27 (30% milkers, 21 (23% day workers, 18 farm professionals (20% and 24 (26% workers in others activities. A total of 22 (24% samples were positive to some test. Twelve (13.3% were positive to Leptospira sp., seven (7.8% to Rickettsia sp

Bacterial diversity and community along the succession of biological soil crusts in the Gurbantunggut Desert, Northern China.

Science.gov (United States)

Zhang, Bingchang; Kong, Weidong; Wu, Nan; Zhang, Yuanming

2016-06-01

Biological soil crusts (BSCs) are common and play critical roles in semi-arid and arid ecosystems. Bacteria, as an important community in BSCs, play critical roles in biochemical processes. However, how bacterial diversity and community change in different successional stages of BSCs is still unknown. We used 454 pyrosequencing of 16S rRNA to investigate the bacterial composition and community, and the relationships between bacterial composition and environmental factors were also explored. In different successional stages of BSCs, the number of bacteria operational taxonomic units (OTUs) detected in each sample ranged from 2572 to 3157. Proteobacteria, Cyanobacteria, Bacteroidetes were dominant in BSCs, followed by Firmicutes, Acidobacteria, and Actinobacteria. At the successional stages of BSCs, bacterial communities, OTU composition and their relative abundance notably differentiated, and Cyanobacteria, especially Microcoleus vaginatus, dominated algal crust and lichen crust, and were the main C-fixing bacteria in BSCs. Proteobacteria and Bacteroidetes increased with the development of BSCs. OTUs related to Planomicrobium Chinese, Desulfobulbus sp., Desulfomicrobium sp., Arthrobacter sp., and Ahhaerbacter sp. showed higher relative abundance in bare sand than other successional stages of BSCs, while relative abundance of Sphingomonas sp. Niastella sp., Pedobacter, Candidatus solobacter, and Streptophyta increased with the development of BSCs. In successional stages of BSCs, bacterial OTUs composition demonstrated strong correlations with soil nutrients, soil salts, and soil enzymes. Additionally, variation of bacterial composition led to different ecological function. In bare sand, some species were related with mineral metabolism or promoting plant growth, and in algal crust and lichen crust, C-fixing bacteria increased and accumulated C to the desert soil. In later developed stage of BSCs, bacteria related with decomposition of organic matter, such as

Biotransformation of 2,4-dinitroanisole by a fungal Penicillium sp.

Science.gov (United States)

Schroer, Hunter W; Langenfeld, Kathryn L; Li, Xueshu; Lehmler, Hans-Joachim; Just, Craig L

2017-02-01

Insensitive munitions explosives are new formulations that are less prone to unintended detonation compared to traditional explosives. While these formulations have safety benefits, the individual constituents, such as 2,4-dinitroanisole (DNAN), have an unknown ecosystem fate with potentially toxic impacts to flora and fauna exposed to DNAN and/or its metabolites. Fungi may be useful in remediation and have been shown to degrade traditional nitroaromatic explosives, such as 2,4,6-trinitrotoluene and 2,4-dinitrotoluene, that are structurally similar to DNAN. In this study, a fungal Penicillium sp., isolated from willow trees and designated strain KH1, was shown to degrade DNAN in solution within 14 days. Stable-isotope labeled DNAN and an untargeted metabolomics approach were used to discover 13 novel transformation products. Penicillium sp. KH1 produced DNAN metabolites resulting from ortho- and para-nitroreduction, demethylation, acetylation, hydroxylation, malonylation, and sulfation. Incubations with intermediate metabolites such as 2-amino-4-nitroanisole and 4-amino-2-nitroanisole as the primary substrates confirmed putative metabolite isomerism and pathways. No ring-cleavage products were observed, consistent with other reports that mineralization of DNAN is an uncommon metabolic outcome. The production of metabolites with unknown persistence and toxicity suggests further study will be needed to implement remediation with Penicillium sp. KH1. To our knowledge, this is the first report on the biotransformation of DNAN by a fungus.

Isolation and identification of bacterial consortia responsible for degrading oil spills from the coastal area of Yanbu, Saudi Arabia

Directory of Open Access Journals (Sweden)

Amr Abd-EL Mooti EL Hanafy

2016-01-01

Full Text Available Twenty-three crude-oil-degrading bacteria were isolated from oil-contaminated sites near the Red Sea. Based on a high growth rate on crude oil and on hydrocarbon degradation ability, four strains were selected from the 23 isolated strains for further study. These four strains were selected on the basis of dichlorophenolindophenol assay. The nucleotide sequences of the 16S rRNA gene showed that these isolated strains belonged to genus Pseudomonas and Nitratireductor. Among the four isolates, strains S5 (Pseudomonas sp., 95% and 4b (Nitratireductor sp., 70% were the most effective ones in degrading crude oil. Using a spectrophotometer and gas chromatography–mass spectrometry, degradation of more than 90% of the crude oil was observed after two weeks of cultivation in Bushnell–Haas medium. The results showed that these strains have the ability to degrade crude oil and may be used for environmental remediation.

Characterization of newly isolated Pseudonocardia sp. N23 with high 1,4-dioxane-degrading ability.

Science.gov (United States)

Yamamoto, Norifumi; Saito, Yuji; Inoue, Daisuke; Sei, Kazunari; Ike, Michihiko

2018-01-02

This study was conducted to elucidate the 1,4-dioxane degradation characteristics of a newly isolated 1,4-dioxane-degrading bacterial strain and evaluate the applicability of the strain to biological 1,4-dioxane removal from wastewater. A bacterial strain (designated strain N23) capable of degrading 1,4-dioxane as the sole carbon and energy source was isolated from an enrichment culture prepared from 1,4-dioxane-contaminated groundwater. Strain N23 was phylogenetically identified as belonging to the genus Pseudonocardia, based on 16S rRNA gene sequencing. 1,4-Dioxane degradation experiments revealed that strain N23 is capable of constitutive 1,4-dioxane degradation. Further, this strain exhibited the highest specific 1,4-dioxane degradation rate of 0.230 mg-1,4-dioxane (mg-protein) -1  h -1 among 1,4-dioxane-degrading bacteria with constitutively expressed degrading enzymes reported to date. In addition, strain N23 was shown to degrade up to 1100 mg L -1 of 1,4-dioxane without significant inhibition, and to maintain a high level of 1,4-dioxane degradation activity under a wide pH (pH 3.8-8.2) and temperature (20-35 °C) range. In particular, the specific 1,4-dioxane degradation rate, even at pH 3.8, was 83% of the highest rate at pH 7.0. In addition, strain N23 was capable of utilizing ethylene glycol and diethylene glycol, which are both considered to be present in 1,4-dioxane-containing industrial wastewater, as the sole carbon source. The present results indicate that strain N23 exhibits the potential for 1,4-dioxane removal from industrial wastewater. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Ideonella sakaiensis sp. nov., isolated from a microbial consortium that degrades poly(ethylene terephthalate).

Science.gov (United States)

Tanasupawat, Somboon; Takehana, Toshihiko; Yoshida, Shosuke; Hiraga, Kazumi; Oda, Kohei

2016-08-01

A Gram-stain-negative, aerobic, non-spore-forming, rod-shaped bacterium, designed strain 201-F6T, was isolated from a microbial consortium that degrades poly(ethylene terephthalate) (PET) collected in Sakai city, Japan, and was characterized on the basis of a polyphasic taxonomic study. The cells were motile with a polar flagellum. The strain contained cytochrome oxidase and catalase. It grew within the pH range 5.5-9.0 (optimally at pH 7-7.5) and at 15-42 ºC (optimally at 30-37 ºC). The major isoprenoid quinone was ubiquinone with eight isoprene units (Q-8). C16 : 0, C17 : 0 cyclo, C18 :1ω7c and C12 : 0 2-OH were the predominant cellular fatty acids. The major polar lipids were phosphatidylethanolamine, lyso-phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The G+C content of genomic DNA was 70.4 mol%. Phylogenetic analysis using the 16S rRNA gene sequences showed that strain 201-F6T was affiliated to the genus Ideonella, and was closely related to Ideonella dechloratans LMG 28178T (97.7 %) and Ideonella azotifigens JCM 15503T (96.6 %). Strain 201-F6T could be clearly distinguished from the related species of the genus Ideonella by its physiological and biochemical characteristics as well as by its phylogenetic position and DNA-DNA relatedness. Therefore, the strain represents a novel species of the genus Ideonella, for which the name Ideonella sakaiensis sp. nov. (type strain 201-F6T=NBRC 110686T=TISTR 2288T) is proposed.

Benzo[a]pyrene co-metabolism in the presence of plant root extracts and exudates: Implications for phytoremediation

International Nuclear Information System (INIS)

Rentz, Jeremy A.; Alvarez, Pedro J.J.; Schnoor, Jerald L.

2005-01-01

Benzo[a]pyrene, a high molecular weight (HMW) polycyclic aromatic hydrocarbon (PAH) was removed from solution by Sphingomonas yanoikuyae JAR02 while growing on root products as a primary carbon and energy source. Plant root extracts of osage orange (Maclura pomifera), hybrid willow (Salix albaxmatsudana), or kou (Cordia subcordata), or plant root exudates of white mulberry (Morus alba) supported 15-20% benzo[a]pyrene removal over 24 h that was similar to a succinate grown culture and an unfed acetonitrile control. No differences were observed between the different root products tested. Mineralization of 14 C-7-benzo[a]pyrene by S. yanoikuyae JAR02 yielded 0.2 to 0.3% 14 CO 2 when grown with plant root products. Collectively, these observations were consistent with field observations of enhanced phytoremediation of HMW PAH and corroborated the hypothesis that co-metabolism may be a plant/microbe interaction important to rhizoremediation. However, degradation and mineralization was much less for root product-exposed cultures than salicylate-induced cultures, and suggested the rhizosphere may not be an optimal environment for HMW PAH degradation by Sphingomonas yanoikuyae JAR02. - Bacterial benzo[a]pyrene cometabolism, a plant-microbe interaction affecting polycyclic aromatic hydrocarbon phytoremediation was demonstrated with Sphingomonas yanoikuyae JAR02 that utilized plant root extracts and exudates as primary substrates

Potential of bacteria isolated from landfill soil in degrading low density polyethylene plastic

Science.gov (United States)

Munir, E.; Sipayung, F. C.; Priyani, N.; Suryanto, D.

2018-03-01

Plastic is an important material and used for many purposes. It is returned to the environment as a waste which is recently considered as the second largest solid waste. The persistency of plastic in the environment has been attracted researchers from a different point of view. The study of the degradation of plastic using bacteria isolated from local landfill soil was conducted. Low density polyethylene (LDPE) plastic was used as tested material. Potential isolates were obtained by culturing the candidates in mineral salt medium broth containing LDPE powder. Two of ten exhibited better growth response in the selection media and were used in degradation study. Results showed that isolate SP2 and SP4 reduced the weight of LDPE film significantly to a weight loss of 10.16% and 12.06%, respectively after four weeks of incubation. Scanning electron micrograph analyses showed the surface of LDPE changed compared to the untreated film. It looked rough and cracked, and bacteria cells attached to the surface was also noticed. Fourier transform infrared spectroscopy analyses confirmed the degradation of LDPE film. These results indicated that bacteria isolated from landfill might play an important role in degrading plastic material in the landfill.

Modified nanocrystal cellulose/fluorene-containing sulfonated poly(ether ether ketone ketone) composites for proton exchange membranes

Science.gov (United States)

Wei, Yingcong; Shang, Yabei; Ni, Chuangjiang; Zhang, Hanyu; Li, Xiaobai; Liu, Baijun; Men, Yongfeng; Zhang, Mingyao; Hu, Wei

2017-09-01

Highly sulfonated poly(ether ether ketone ketone)s (SFPEEKKs) with sulfonation degrees of 2.34 (SFPEEKK5) and 2.48 (SFPEEKK10) were synthesized through the direct sulfonation of a fluorene-containing poly(ether ether ketone ketone) under a relatively mild reaction condition. Using the solution blending method, sulfonated nanocrystal cellulose (sNCC)-enhanced SFPEEKK composites (SFPEEKK/sNCC) were successfully prepared for investigation as proton exchange membranes. Transmission electron microscopy showed that sNCC was uniformly distributed in the composite membranes. The properties of the composite membranes, including thermal stability, mechanical properties, water uptake, swelling ratio, oxidative stability and proton conductivity were thoroughly evaluated. Results indicated that the insertion of sNCC could contribute to water management and improve the mechanical performance of the membranes. Notably, the proton conductivity of SFPEEKK5/sNCC-5 was as high as 0.242 S cm-1 at 80 °C. All data proved the potential of SFPEEKK/sNCC composites for proton exchange membranes in medium-temperature fuel cells.

Effect of fusarium oxysporum f. sp. lycopersici on the degradation of humic acid associated with Cu, Pb, and Ni: an in vitro study

Energy Technology Data Exchange (ETDEWEB)

Corrales Escobosa, Alma Rosa; Gutierrez Corona, J.F. [University of Guanajuato, Department of Biology, Guanajuato (Mexico); Landero Figueroa, Julio Alberto; Wrobel, Katarzyna; Wrobel, Kazimierz [University of Guanajuato, Department of Chemistry, Guanajuato (Mexico)

2009-08-15

The intent of this work was to gain further insight on the fungus-assisted degradation/solubilization of humic acid and the related changes in metal-binding profiles. In the experimental design, Aldrich reagent humic acid (HA) or HA enriched with Cu, Pb, and Ni (HA(Me)) was added to Fusarium oxysporum f. sp. lycopersici cultures in vitro. The cultures were supplied by different carbon- and nitrogen-containing nutrients (glucose, Glc, or glutamate, Glu and ammonium, NH{sub 4}{sup +}, or nitrate, NO{sub 3}{sup -}, ions, respectively) in order to examine their possible effect on HA and HA(Me) decomposition. During the first 48 h of fungus growth, gradual acidification to pH 2 was observed in medium containing Glc+NH{sub 4}{sup +}, while for other cultures, alkalinization to pH 9 occurred and then, the above conditions were stable up to at least 200 h. Size exclusion chromatography (SEC) with UV/Vis detection showed progressive degradation and solubilization of both HA and HA(Me) with the increasing time of fungus growth. However, the molecular mass distributions of HA-related soluble species were different in the presence of metals (HA(Me)) as referred to HA and were also influenced by the composition of growth medium. The solubilization of Pb, Cu, and Ni and their association with HA molecular mass fractions were studied using inductively coupled plasma mass spectrometry (ICP-MS) detection. Under acidic conditions, relatively high concentrations of low-molecular-mass metallic species were found in culture supernatants, while in alkaline media, metal solubilization was generally poorer. In contrast to low pH culture, SEC-ICP-MS results obtained in alkaline supernatants indicated metal binding to degradation products of humic substances of MM>5 kDa. In summary, the results of this study suggest that fungus-assisted degradation of HA and HA(Me) might be controlled using appropriate N- and C-sources required for fungus growth, which in turn would affect molecular mass

Effect of Fusarium oxysporum f. sp. lycopersici on the degradation of humic acid associated with Cu, Pb, and Ni: an in vitro study.

Science.gov (United States)

Corrales Escobosa, Alma Rosa; Landero Figueroa, Julio Alberto; Gutiérrez Corona, J Félix; Wrobel, Katarzyna; Wrobel, Kazimierz

2009-08-01

The intent of this work was to gain further insight on the fungus-assisted degradation/solubilization of humic acid and the related changes in metal-binding profiles. In the experimental design, Aldrich reagent humic acid (HA) or HA enriched with Cu, Pb, and Ni (HA(Me)) was added to Fusarium oxysporum f. sp. lycopersici cultures in vitro. The cultures were supplied by different carbon- and nitrogen-containing nutrients (glucose, Glc, or glutamate, Glu and ammonium, NH4+, or nitrate, NO3-, ions, respectively) in order to examine their possible effect on HA and HA(Me) decomposition. During the first 48 h of fungus growth, gradual acidification to pH 2 was observed in medium containing Glc + NH4+, while for other cultures, alkalinization to pH 9 occurred and then, the above conditions were stable up to at least 200 h. Size exclusion chromatography (SEC) with UV/Vis detection showed progressive degradation and solubilization of both HA and HA(Me) with the increasing time of fungus growth. However, the molecular mass distributions of HA-related soluble species were different in the presence of metals (HA(Me)) as referred to HA and were also influenced by the composition of growth medium. The solubilization of Pb, Cu, and Ni and their association with HA molecular mass fractions were studied using inductively coupled plasma mass spectrometry (ICP-MS) detection. Under acidic conditions, relatively high concentrations of low-molecular-mass metallic species were found in culture supernatants, while in alkaline media, metal solubilization was generally poorer. In contrast to low pH culture, SEC-ICP-MS results obtained in alkaline supernatants indicated metal binding to degradation products of humic substances of MM > 5 kDa. In summary, the results of this study suggest that fungus-assisted degradation of HA and HA(Me) might be controlled using appropriate N- and C- sources required for fungus growth, which in turn would affect molecular mass distribution of soluble metallic

Fungal hyphae stimulate bacterial degradation of 2,6-dichlorobenzamide (BAM).

Science.gov (United States)

Knudsen, Berith Elkær; Ellegaard-Jensen, Lea; Albers, Christian Nyrop; Rosendahl, Søren; Aamand, Jens

2013-10-01

Introduction of specific degrading microorganisms into polluted soil or aquifers is a promising remediation technology provided that the organisms survive and spread in the environment. We suggest that consortia, rather than single strains, may be better suited to overcome these challenges. Here we introduced a fungal-bacterial consortium consisting of Mortierella sp. LEJ702 and the 2,6-dichlorobenzamide (BAM)-degrading Aminobacter sp. MSH1 into small sand columns. A more rapid mineralisation of BAM was obtained by the consortium compared to MSH1 alone especially at lower moisture contents. Results from quantitative real-time polymerase chain reaction (qPCR) demonstrated better spreading of Aminobacter when Mortierella was present suggesting that fungal hyphae may stimulate bacterial dispersal. Extraction and analysis of BAM indicated that translocation of the compound was also affected by the fungal hyphae in the sand. This suggests that fungal-bacterial consortia are promising for successful bioremediation of pesticide contamination. Copyright © 2013 Elsevier Ltd. All rights reserved.

Potential of the strain Raoultella sp KDF8 for removal of analgesics

Czech Academy of Sciences Publication Activity Database

Palyzová, Andrea; Zahradník, Jiří; Marešová, Helena; Sokolová, Lucie; Kyslíková, Eva; Grulich, Michal; Štěpánek, Václav; Řezanka, Tomáš; Kyslík, Pavel

2018-01-01

Roč. 63, č. 3 (2018), s. 273-282 ISSN 0015-5632 R&D Projects: GA TA ČR TH02030337 Institutional support: RVO:61388971 ; RVO:86652036 Keywords : Microbial degradation * Raoultella sp. * Analgesics Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 1.521, year: 2016

Enhanced degradation of chitosan by applying plasma treatment in combination with oxidizing agents for potential use as an anticancer agent.

Science.gov (United States)

Chokradjaroen, Chayanaphat; Rujiravanit, Ratana; Watthanaphanit, Anyarat; Theeramunkong, Sewan; Saito, Nagahiro; Yamashita, Kazuko; Arakawa, Ryuichi

2017-07-01

Solution plasma (SP) treatment in combination with oxidizing agents, i.e., hydrogen peroxide (H 2 O 2 ), potassium persulfate (K 2 S 2 O 8 ) and sodium nitrite (NaNO 2 ) were adopted to chitosan degradation in order to achieve fast degradation rate, low chemicals used and high yield of low-molecular-weight chitosan and chitooligosaccharide (COS). Among the studied oxidizing agents, H 2 O 2 was found to be the best choice in terms of appreciable molecular weight reduction without major change in chemical structure of the degraded products of chitosan. By the combination with SP treatment, dilute solution of H 2 O 2 (4-60mM) was required for effective degradation of chitosan. The combination of SP treatment and dilute solution of H 2 O 2 (60mM) resulted in the great reduction of molecular weight of chitosan and water-soluble chitosan was obtained as a major product. The resulting water-soluble chitosan was precipitated to obtain COS. An inhibitory effect against cervical cancer cell line (HeLa cells) of COS was also examined. Copyright © 2017 Elsevier Ltd. All rights reserved.

Rapid anaerobic mineralization of pyridine in a subsurface sediment inoculated with a pyridine-degrading Alcaligenes sp

Energy Technology Data Exchange (ETDEWEB)

Ronen, Z; Bollag, J M [Pennsylvania State Univ., University Park, PA (United States). Lab. of Soil Biochemistry

1992-05-01

A denitrifying bacterium capable of pyridine mineralization under anaerobic conditions was isolated from polluted soil. The bacterium, identified as Alcaligenes sp., was used in inoculation experiments. A subsurface sediment from a polluted site was amended with 10 {mu}g/g {sup 14}C-labeled pyridine, and 250 {mu}g/g nitrate, and then inoculated with the bacterium at an inoculum size of 4.5x10{sup 7} cells/g. After 44 h incubation at 28deg C under anaerobic conditions, 67% of the radioactivity was recovered as {sup 14}CO{sub 2}: 2% was extracted with 50% methanol, and 24% was recovered by combustion of the sediment. Analysis of the methanol extract revealed that no pyridine could be detected in the inoculated sediment. In contrast, mineralization of pyridine by the native microflora in the sediment occurred much more slowly: After 7 days of incubation only 10% of the added radioactivity was recovered as {sup 14}CO{sub 2}. At an inoculum size of 2x10{sup 3} cells/g pyridine mineralization was not as effective as at an inoculum size of 2x10{sup 7} cells/g. It is presumed that suppression of the introduced bacteria by the native microflora of the sediment prevents degradation at a low inoculum size. Amending the sediment with nitrate and phosphate improved pyridine mineralization by the introduced bacterium. These findings demonstrate the feasibility of using soil inoculation anaerobically for the bioremediation of pyridine-polluted soils. (orig.).

Biofilm Formation on Reverse Osmosis Membranes Is Initiated and Dominated by Sphingomonas spp.▿ †

Science.gov (United States)

Bereschenko, L. A.; Stams, A. J. M.; Euverink, G. J. W.; van Loosdrecht, M. C. M.

2010-01-01

The initial formation and spatiotemporal development of microbial biofilm layers on surfaces of new and clean reverse osmosis (RO) membranes and feed-side spacers were monitored in situ using flow cells placed in parallel with the RO system of a full-scale water treatment plant. The feed water of the RO system had been treated by the sequential application of coagulation, flocculation, sand filtration, ultrafiltration, and cartridge filtration processes. The design of the flow cells permitted the production of permeate under cross-flow conditions similar to those in spiral-wound RO membrane elements of the full-scale system. Membrane autopsies were done after 4, 8, 16, and 32 days of flow-cell operation. A combination of molecular (fluorescence in situ hybridization [FISH], denaturing gradient gel electrophoresis [DGGE], and cloning) and microscopic (field emission scanning electron, epifluorescence, and confocal laser scanning microscopy) techniques was applied to analyze the abundance, composition, architecture, and three-dimensional structure of biofilm communities. The results of the study point out the unique role of Sphingomonas spp. in the initial formation and subsequent maturation of biofilms on the RO membrane and feed-side spacer surfaces. PMID:20190090

Decolorization of two azo dyes using marine Lysobacter sp. T312D9

Directory of Open Access Journals (Sweden)

Khouloud M. I. B.

2013-01-01

Full Text Available Aims: Novel azo dye-degrading bacterium T312D9 strain has been isolated from Abou Quir Gulf, Alexandria, Egypt. Methodology and Results: The identification of the isolate by 16S rRNA gene sequencing revealed to be Lysobacter sp. This marine ecofriendly isolate was exploited for its ability to degrade two synthetic azo dyes considered as detrimental pollutants from industrial effluents: congo red and methyl red. Using different dye concentrations showed the highest metabolic activity for complete degradation obtained from 100 to 500 mg/L within 30 h under static condition, also, sustaining higher dye loading of 1 g/L was carried out. The significant induction of enzymes NADH - 2,6-dichloroindophenol (NADH-DCIP reductase and tyrosinaseindicated their prominent role in dye degradation. The biodegradation of two azo dyes were analyzed by gas chromatographicmass spectrum analysis (GC-MS and Fourier transform infrared spectroscopy (FTIR before and after treatment. Toxicity study revealed the much less toxic nature of the metabolites produced after complete decolorization. Conclusion, significance and impact of study: Lysobacter sp T312D9 represent an inexpensive and promising marine bacteria for removal of both methyl and congo red. High sustainable metabolic activity for biodegradation under static condition. NADHDCIPreductase and tyrosinase were significantly induced during biodegradation of dyes. The obtained metabolites revealed to beless toxic in nature which offers a practical biological treatment.

Multifarious activities of cellulose degrading bacteria from Koala (Phascolarctos cinereus) faeces.

Science.gov (United States)

Singh, Surender; Thavamani, Palanisami; Megharaj, Mallavarapu; Naidu, Ravi

2015-01-01

Cellulose degrading bacteria from koala faeces were isolated using caboxymethylcellulose-Congo red agar, screened in vitro for different hydrolytic enzyme activities and phylogenetically characterized using molecular tools. Bacillus sp. and Pseudomonas sp. were the most prominent bacteria from koala faeces. The isolates demonstrated good xylanase, amylase, lipase, protease, tannase and lignin peroxidase activities apart from endoglucanase activity. Furthermore many isolates grew in the presence of phenanthrene, indicating their probable application for bioremediation. Potential isolates can be exploited further for industrial enzyme production or in bioremediation of contaminated sites.

Identification and characterization of epoxide hydrolase activity of polycyclic aromatic hydrocarbon-degrading bacteria for biocatalytic resolution of racemic styrene oxide and styrene oxide derivatives.

Science.gov (United States)

Woo, Jung-Hee; Kwon, Tae-Hyung; Kim, Jun-Tae; Kim, Choong-Gon; Lee, Eun Yeol

2013-04-01

A novel epoxide hydrolase (EHase) from polycyclic aromatic hydrocarbon (PAH)-degrading bacteria was identified and characterized. EHase activity was identified in four strains of PAH-degrading bacteria isolated from commercial gasoline and oil-contaminated sediment based on their growth on styrene oxide and its derivatives, such as 2,3- and 4-chlorostyrene oxides, as a sole carbon source. Gordonia sp. H37 exhibited high enantioselective hydrolysis activity for 4-chlorostyrene oxide with an enantiomeric ratio of 27. Gordonia sp. H37 preferentially hydrolyzed the (R)-enantiomer of styrene oxide derivatives resulting in the preparation of a (S)-enantiomer with enantiomeric excess greater than 99.9 %. The enantioselective EHase activity was identified and characterized in various PAH-degrading bacteria, and whole cell Gordonia sp. H37 was employed as a biocatalyst for preparing enantiopure (S)-styrene oxide derivatives.

Asymmetric transfer hydrogenation of ketones in aqueous solution catalyzed by Rhodium(III) complexes with C2-symmetric fluorene-ligands containing chiral (1R,2R)-cyclohexane-1,2-diamine

International Nuclear Information System (INIS)

Montalvo-Gonzalez, Ruben; Chavez, Daniel; Aguirre, Gerardo; Parra-Hake, Miguel; Somanathan, Ratnasamy

2010-01-01

Two C 2 -symmetric bis(sulfonamide) ligands containing fluorene-chiral (1R, 2R)-cyclohexane-1,2-diamine were complexed to Rh III (Cp * ) and used as catalyst to reduce aromatic ketones. The corresponding chiral secondary alcohols were obtained in 87-100% ee and 85-99% yield, under asymmetric transfer hydrogenation (ATH) conditions using aqueous sodium formate as the hydride source. With acetophenone, 94% ee and 86-97% yield was achieved with substrate/catalyst (S/C) ratio of 10,000. (author)

Upgrading of highly elapsed degradation damage evaluation of structural materials for the light water reactors

International Nuclear Information System (INIS)

Katada, Yasuyuki; Matsushima, Shinobu; Sato, Shunji

1998-01-01

In this study, for degradation of structural materials in accompanying with highly yearly lapse of the nuclear power plants, it was an aim to elucidate interaction between material degradation and degradation under high hot water environment. And, another aims consisted in intention of expansion protection and recovery evaluation of damage due to laser processing method and so on for welded portion showing extreme material degradation and in preparation of damage region diagram based on the obtained data. In this fiscal year, on interaction between materials and environmental degradation, it was found that as stress corrosion cracking of materials hardened by shot peening shows a resemble shapes of stress-strain curve in CERT and CLRT, shapes of load-time curve were much different. On comparison of the SP material and non-processing material, as peak current showing activity of newly created surface shows no difference, re-passivation of the SP material was found to be too late. And, on recovery evaluation of material degradation damage, as it was found that constant melt depth was essential to evaluate corrosion, a condition preparation aimed for melt depth of more than 1 mm. As only small amount of bubbles were observed at molten metal part on YAG laser processing, it was found that many small bubbles scatter at thermal effect part. (G.K.)

Characterization of Carbofuran Degrading Bacteria Obtained from Potato Cultivated Soils with Different Pesticide Application Records / Caracterización de Bacterias Degradadoras de Carbofuran Obtenidas de Suelos Bajo Cultivo de Papa y con Diferente Histor

Directory of Open Access Journals (Sweden)

Castellanos Rozo José

2013-08-01

Full Text Available Abstract. Eighty-two bacterial isolates with potential Carbofurandegradation activity (Furadan®3SC were obtained from soilscultivated with the potato variety Unica (Solanum tuberosumin Silos, Norte de Santander (Colombia, with different recordsof pesticide application. The bacteria were selected for theirability to grow at 25 °C for 72 h in media containing 200 mgL-1 of analytical Carbofuran as the sole source of carbon and/or nitrogen. The results showed that ten isolates, 12% of those obtained, grew in the culture media. Eight of theses isolates were obtained from soils with a high pesticide exposure (eight years of application, and identified, by macroscopic, microscopic and biochemical characteristics, as Sphingomonas paucimobilis. The other two were obtained from soils with three years and one year of application and were identified as Pseudomonas aeruginosa and Yersinia pseudotuberculosis, respectively. Subsequently, these bacteria were tested for their ability of hydrolytic degradation of Carbofuran; the results show that the pesticide was degraded only by the isolates of Sphingomonas paucimobilis for 72 h. The results obtained in the in vitro tests show the bacterial metabolic capacity for the biodegradation of Carbofuran, highlighting the potential use of the bacteria for future field evaluation tests in places where residues of the pesticide may exist, as an alternative to control the impact that N-methyl carbamate pesticides have on the environment and human health. / Resumen. Ochenta y dos aislamientos bacterianos con actividad potencial de degradación de Carbofuran (Furadan®3SC, fueron obtenidos de suelos, cultivados con papa (Solanum tuberosum variedad Única, del municipio de Silos, Norte de Santander (Colombia con diferente historia de aplicación del plaguicida. Las bacterias fueron seleccionadas por su capacidad para crecer a 25 °C durante 72 h, en medios de cultivo conteniendo 200 mg L-1 de Carbofuran analítico como

Comparison of Rumen Degradation Characteristics between Pennisetum sp.and Commonly Used Roughages for Dairy Cows%禾王草与奶牛常用粗饲料瘤胃降解特性的对比研究

Institute of Scientific and Technical Information of China (English)

马健; 刘艳芳; 杜云; 李胜利; 余雄

2016-01-01

本试验旨在研究2种刈割高度的禾王草干草和青贮、羊草干草、苜蓿干草以及全株玉米青贮共7种粗饲料的瘤胃降解特性。选用4头装有永久性瘤胃瘘管的荷斯坦奶牛为试验动物，采用尼龙袋法评定其干物质（ DM）、粗蛋白质（ CP）、中性洗涤纤维（ NDF）和酸性洗涤纤维（ ADF）的72 h瘤胃降解率。结果表明：1）禾王草干草CP含量显著高于羊草干草（ P＜0．05）， NDF含量显著低于羊草干草（ P＜0．05）；禾王草青贮CP和NDF含量显著高于全株玉米青贮（ P＜0．05）。2）苜蓿干草DM有效降解率最高，与依次降低的全株玉米青贮、2．0 m禾王草青贮、2．5 m禾王草青贮、2．0 m禾王草干草、2．5 m禾王草干草和羊草干草差异显著（ P＜0．05），羊草干草的DM有效降解率显著低于其他粗饲料（ P＜0．05）；CP有效降解率以苜蓿干草最高，与2．0 m禾王草青贮差异不显著（ P＞0．05），显著高于依次降低的2．5 m禾王草青贮、2．0 m禾王草干草、全株玉米青贮、2．5 m禾王草干草和羊草干草（ P＜0．05）；全株玉米青贮与禾王草青贮的NDF有效降解率差异不显著（ P＞0．05），而显著高于其他粗饲料（ P＜0．05）；禾王草青贮72 h时ADF有效降解率显著高于其他粗饲料（ P＜0．05）。由此可知，禾王草有作为奶牛粗饲料的潜力，禾王草经青贮后可以保存营养成分，并可以提高营养成分的瘤胃利用效率。%This experiment was conducted to determine the rumen degradation characteristics of 7 kinds of roughages including 2 kinds of Pennisetum sp.hay ( different cutting height) , 2 kinds of Pennisetum sp.silage ( different cutting height) , dried Chinese wildye, dried alfalfa hay and whole corn silage.Four Holstein cows with permanent ruminal cannulas were used.Nylon-bag technique was used to evaluate the ruminal degradabili-ty of dry matter

Biodegradation of chlorpyrifos and its hydrolysis product 3,5,6-trichloro-2-pyridinol using a novel bacterium Ochrobactrum sp. JAS2: A proposal of its metabolic pathway.

Science.gov (United States)

Abraham, Jayanthi; Silambarasan, Sivagnanam

2016-01-01

Biodegradation of chlorpyrifos and its major metabolite 3,5,6-trichloro-2-pyridinol (TCP) were studied with a novel bacterial strain JAS2 isolated from paddy rhizosphere soil. The molecular characterization based on 16S rRNA gene sequence homology confirmed its identity as Ochrobactrum sp. JAS2. The JAS2 strain degraded 300mgl(-1) of chlorpyrifos within 12h of incubation in the aqueous medium and it produced the TCP metabolite. However, after 72h of incubation TCP was also completely degraded by the JAS2 strain. A tentative degradation pathway of chlorpyrifos by Ochrobactrum sp. JAS2 has been proposed on basis of GC-MS analysis. The complete degradation of chlorpyrifos occurred within 24h in the soil spiked with and without addition of nutrients inoculated with Ochrobactrum sp. JAS2. TCP was obtained in both the studies which was degraded completely by 96h in the soil spiked with nutrients and whereas 120h in absence of nutrients in the soil. The mpd gene which is responsible for organophosphorus hydrolase production was identified. The isolates Ochrobactrum sp. JAS2 also exhibited a time dependent increase in the amount of tricalcium phosphate solubilization in Pikovskaya's medium. Further screening of the strain JAS2 for auxiliary plant growth promoting activities revealed its remarkable capability of producing the indole acetic acid (IAA), hydrogen cyanide (HCN) and ammonia. Copyright © 2015 Elsevier B.V. All rights reserved.

Identification of the para-nitrophenol catabolic pathway, and characterization of three enzymes involved in the hydroquinone pathway, in pseudomonas sp. 1-7

Directory of Open Access Journals (Sweden)

Zhang Shuangyu

2012-03-01

Full Text Available Abstract Background para-Nitrophenol (PNP, a priority environmental pollutant, is hazardous to humans and animals. However, the information relating to the PNP degradation pathways and their enzymes remain limited. Results Pseudomonas sp.1-7 was isolated from methyl parathion (MP-polluted activated sludge and was shown to degrade PNP. Two different intermediates, hydroquinone (HQ and 4-nitrocatechol (4-NC were detected in the catabolism of PNP. This indicated that Pseudomonas sp.1-7 degraded PNP by two different pathways, namely the HQ pathway, and the hydroxyquinol (BT pathway (also referred to as the 4-NC pathway. A gene cluster (pdcEDGFCBA was identified in a 10.6 kb DNA fragment of a fosmid library, which cluster encoded the following enzymes involved in PNP degradation: PNP 4-monooxygenase (PdcA, p-benzoquinone (BQ reductase (PdcB, hydroxyquinol (BT 1,2-dioxygenase (PdcC, maleylacetate (MA reductase (PdcF, 4-hydroxymuconic semialdehyde (4-HS dehydrogenase (PdcG, and hydroquinone (HQ 1,2-dioxygenase (PdcDE. Four genes (pdcDEFG were expressed in E. coli and the purified pdcDE, pdcG and pdcF gene products were shown to convert HQ to 4-HS, 4-HS to MA and MA to β-ketoadipate respectively by in vitro activity assays. Conclusions The cloning, sequencing, and characterization of these genes along with the functional PNP degradation studies identified 4-NC, HQ, 4-HS, and MA as intermediates in the degradation pathway of PNP by Pseudomonas sp.1-7. This is the first conclusive report for both 4-NC and HQ- mediated degradation of PNP by one microorganism.

Diesel oil removal by immobilized Pseudoxanthomonas sp. RN402.

Science.gov (United States)

Nopcharoenkul, Wannarak; Netsakulnee, Parichat; Pinyakong, Onruthai

2013-06-01

Pseudoxanthomonas sp. RN402 was capable of degrading diesel, crude oil, n-tetradecane and n-hexadecane. The RN402 cells were immobilized on the surface of high-density polyethylene plastic pellets at a maximum cell density of 10(8) most probable number (MPN) g(-1) of plastic pellets. The immobilized cells not only showed a higher efficacy of diesel oil removal than free cells but could also degrade higher concentrations of diesel oil. The rate of diesel oil removal by immobilized RN402 cells in liquid culture was 1,050 mg l(-1) day(-1). Moreover, the immobilized cells could maintain high efficacy and viability throughout 70 cycles of bioremedial treatment of diesel-contaminated water. The stability of diesel oil degradation in the immobilized cells resulted from the ability of living RN402 cells to attach to material surfaces by biofilm formation, as was shown by CLSM imaging. These characteristics of the immobilized RN402 cells, including high degradative efficacy, stability and flotation, make them suitable for the purpose of continuous wastewater bioremediation.

Airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 for treatment of lubricants in wastewater

Energy Technology Data Exchange (ETDEWEB)

Khondee, Nichakorn; Tathong, Sitti [International Postgraduate Programs in Environmental Management, Graduate School, Chulalongkorn University, Bangkok (Thailand); Bioremediation Research Unit, Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); Pinyakong, Onruthai [Bioremediation Research Unit, Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); National Center of Excellence for Environmental and Hazardous Waste Management (NCE-EHWM), Chulalongkorn University, Bangkok (Thailand); Powtongsook, Sorawit [Center of Excellence for Marine Biotechnology (c/o Department of Marine Science, Chulalongkorn University), National Center for Genetic Engineering and Biotechnology, Pathum Thani (Thailand); Chatchupong, Thawach; Ruangchainikom, Chalermchai [Environmental Research and Management Department, PTT Research and Technology Institute, Ayutthaya (Thailand); Luepromchai, Ekawan, E-mail: ekawan.l@chula.ac.th [Bioremediation Research Unit, Department of Microbiology, Faculty of Science, Chulalongkorn University, Bangkok (Thailand); National Center of Excellence for Environmental and Hazardous Waste Management (NCE-EHWM), Chulalongkorn University, Bangkok (Thailand)

2012-04-30

Highlights: Black-Right-Pointing-Pointer Sphingobium sp. P2 effectively degraded various lubricant samples. Black-Right-Pointing-Pointer Efficiency of Sphingobium sp. P2 increased after immobilization on chitosan. Black-Right-Pointing-Pointer High removal efficiency was due to both sorption and degradation processes. Black-Right-Pointing-Pointer The immobilized bacteria (4 g L{sup -1}) were applied in internal loop airlift bioreactor. Black-Right-Pointing-Pointer The bioreactor continuously removed lubricant from emulsified wastewater. - Abstract: An internal loop airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 was applied for the removal of automotive lubricants from emulsified wastewater. The chitosan-immobilized bacteria had higher lubricant removal efficiency than free and killed-immobilized cells because they were able to sorp and degrade the lubricants simultaneously. In a semi-continuous batch experiment, the immobilized bacteria were able to remove 80-90% of the 200 mg L{sup -1} total petroleum hydrocarbons (TPH) from both synthetic and carwash wastewater. The internal loop airlift bioreactor, containing 4 g L{sup -1} immobilized bacteria, was later designed and operated at 2.0 h HRT (hydraulic retention time) for over 70 days. At a steady state, the reactor continuously removed 85 {+-} 5% TPH and 73 {+-} 11% chemical oxygen demand (COD) from the carwash wastewater with 25-200 mg L{sup -1} amended lubricant. The internal loop airlift reactor's simple operation and high stability demonstrate its high potential for use in treating lubricants in emulsified wastewater from carwashes and other industries.

Airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 for treatment of lubricants in wastewater

International Nuclear Information System (INIS)

Khondee, Nichakorn; Tathong, Sitti; Pinyakong, Onruthai; Powtongsook, Sorawit; Chatchupong, Thawach; Ruangchainikom, Chalermchai; Luepromchai, Ekawan

2012-01-01

Highlights: ► Sphingobium sp. P2 effectively degraded various lubricant samples. ► Efficiency of Sphingobium sp. P2 increased after immobilization on chitosan. ► High removal efficiency was due to both sorption and degradation processes. ► The immobilized bacteria (4 g L −1 ) were applied in internal loop airlift bioreactor. ► The bioreactor continuously removed lubricant from emulsified wastewater. - Abstract: An internal loop airlift bioreactor containing chitosan-immobilized Sphingobium sp. P2 was applied for the removal of automotive lubricants from emulsified wastewater. The chitosan-immobilized bacteria had higher lubricant removal efficiency than free and killed-immobilized cells because they were able to sorp and degrade the lubricants simultaneously. In a semi-continuous batch experiment, the immobilized bacteria were able to remove 80–90% of the 200 mg L −1 total petroleum hydrocarbons (TPH) from both synthetic and carwash wastewater. The internal loop airlift bioreactor, containing 4 g L −1 immobilized bacteria, was later designed and operated at 2.0 h HRT (hydraulic retention time) for over 70 days. At a steady state, the reactor continuously removed 85 ± 5% TPH and 73 ± 11% chemical oxygen demand (COD) from the carwash wastewater with 25–200 mg L −1 amended lubricant. The internal loop airlift reactor's simple operation and high stability demonstrate its high potential for use in treating lubricants in emulsified wastewater from carwashes and other industries.

Polycyclic aromatic hydrocarbon degradation by the white rot fungus Bjerkandera sp. strain BOS55

NARCIS (Netherlands)

Kotterman, M.

1998-01-01

Outline of this thesis
In this thesis the conditions for optimal PAH oxidation by the white rot fungus Bjerkandera sp. strain BOS55 were evaluated. In Chapter 2, culture conditions like aeration and cosubstrate concentrations,

Anaerobic Co-Digestion of the Microalgae Scenedesmus Sp.

Energy Technology Data Exchange (ETDEWEB)

Ramos-Suarez, J. L.; Carreras, N.

2011-06-07

Microalgae biomass has been widely studied for biogas production over the last years and results show that anaerobic digestion is often limited by the low C/N ratio of this type of biomass. Therefore, codigestion with substrates of high C/N ratio is necessary. The objectives of this study are to set up an experimental method that ease reproducibility and control of anaerobic digestion processes in laboratory conditions and to determine the biodegradability and biogas production potential of the co-digestion process of microalgae Scenedesmus sp. and energy crop Opuntia ficus indica (L.) Miller. Results obtained showed that higher C/N ratios are preferred in order to maximize methane production. Highest methane yield obtained was 0.252m3CH4/Kg VS and degradability expressed as percentage COD reduced is around 30% for the ideal mixture found, made up of 75% O. ficus-indica and 25% Scenedesmus sp. in VS basis. A laboratory setup using MicroOxymax respirometer, after its adaptation to work under anaerobic conditions, can be used for the monitoring of anaerobic digestion processes. Scenedesmus sp. as sole substrate for anaerobic digestion does not give good results due to low C/N ratio. However, when codigesting it with O. ficus-indica methane production is satisfactory. Best mixture was made up of 75% O. ficus-indica and 25% Scenedesmus sp. in VS basis. (Author)

Decolorization and detoxification of Synozol red HF-6BN azo dye, by Aspergillus niger and Nigrospora sp

Directory of Open Access Journals (Sweden)

Sidra Ilyas

2013-01-01

Full Text Available In the present investigation the fungi, Aspergillus niger and Nigrospora sp. were employed for decolorization of Synazol red HF-6BN. Decolorization study showed that Aspergillus niger and Nigrospora sp. were able to decolorize 88% and 96% Synazol red 6BN, respectively, in 24 days. It was also studied that 86% and 90% Synazol red containing of dye effluent was decolorized by Aspergillus niger and Nigrospora sp. after 28 days of incubation at room temperature. A fungal-based protein with relative molecular mass of 70 kDa was partially purified and examined for enzymatic characteristics. The enzyme exhibited highest activity at temperature ranging from 40-50[degree sign]C and at pH=6.0. The enzyme activity was enhanced in the presence of metal cations. High performance liquid chromatography analysis confirmed that these fungal strains are capable to degrade Synazol red dye into metabolites. No zones of inhibition on agar plates and growth of Vigna radiata in the presence of dye extracted sample, indicated that the fungal degraded dye metabolites are nontoxic to beneficial micro-flora and plant growth. Aspergillus niger and Nigrospora sp. have promising potential in color removal from textile wastewater-containing azo dyes.

PENGGUNAAN EKSTRAK BIOTA LAUTAGLAOPHENIA SP. UNTUK MENGENDALIKANFUSARIUM OXYSPORUM F.SP.VANILLAE PENYEBAB BUSUK BATANG VANILI

Directory of Open Access Journals (Sweden)

I KETUT SUADA

2012-11-01

Full Text Available The Use of Aglaophenia sp. Marine Biota Extract to Control Fusarium oxysporum f. sp. vanillae, a Pathogen of Vanilla Stem Rot The use of marine biota for organic fungicide material has enormous potential to be developed. The organic fungicide was directed to substitute synthetic fungicide for vanilla cultivation. Application of synthetic fungicide degraded environmental quality, therefore its applications does not support sustainable agriculture. The objective of this research was to know the potence of Aglaopheniain suppressing the growth of F. oxysporum f. sp.vanillae, the pathogen of vanilla stem rot. The research was done in green house in order to find the best substance for formulation of the extract. The substances screened were water, tween-80, and detergents with two different concentrations. Subsequently, two best formulas were chosen to apply in endemic area in Tabanan. The green house and field trial research used Randomized Completely Design with three and five replications respectively. Results showed that tween was the best substance used for formulation and concentration of 0.2% was better than other concentrations. The extract diluted in tween-80 on the concentration of 0.2% showed the lowest rot on stem, longest shoot, and the most leaves on vanilla shoot. Because of its significant performance, the 0.1% extract ofAglaopheniain 0.1% tween-80 was proposed to be the best formula to suppress the vanilla stem rot disease.

Kinetics of petroleum oil biodegradation by a consortium of three protozoan isolates (Aspidisca sp., Trachelophyllum sp. and Peranema sp.

Directory of Open Access Journals (Sweden)

L. Kachieng’a

2017-09-01

Full Text Available Petroleum oil is a complex mixture of substances, the majority of which are hydrocarbons; the latter represent an extremely important and heterogeneous group of compounds that find their way into water resources by anthropogenic or natural ways. The majority of toxic hydrocarbon components of petroleum are biodegradable, where bioremediation using microbial species has become an integral process for the restoration of oil-polluted areas. In this study, three bioremediation processes, namely natural attenuation, nutrient supplementation by adding glucose and biostimulation by adding Tween® 80, were carried out in various petroleum hydrocarbon concentrations in polluted water media using a consortium of three protozoan isolates (Aspidisca sp., Trachelophyllum sp. and Peranema sp.. A first-order kinetics model was fitted to the biodegradation data to evaluate the biodegradation rate and to determine the corresponding half-life time. First-order kinetics satisfactorily described the biodegradation of the petroleum-based contaminants under abiotic conditions. The results showed an increase in the percentage removal of petroleum oil at the lower petroleum concentrations and a gradual percentage decrease in removing petroleum oil residues occurred when there was an increase in the initial concentrations of the petroleum oil: 39%, 27%, 22%, 12%, 10% for various petroleum oil concentrations of 50, 100, 150, 200, 250 mg/L, respectively. A similar trend was also observed in the glucose-supplemented culture media where the reduction was 45% and 78% for petroleum concentrations of 250 mg/L and 50 mg/L, respectively. Biodegradation of between 33 and 90% was achieved at a Tween® 80 concentration of between 50 mg/L and 250 mg/L. The degradation rate constants for the natural attenuation process ranged between ≥0 to ≤0.50, ≥0 to ≤0.35, ≥0 to ≤0.25, ≥0 to ≤ 0.14 and ≥ 0 to ≤0.11 for petroleum oil concentrations varying from 50, 100, 150

Asymmetric transfer hydrogenation of ketones in aqueous solution catalyzed by Rhodium(III) complexes with C2-symmetric fluorene-ligands containing chiral (1R,2R)-cyclohexane-1,2-diamine

Energy Technology Data Exchange (ETDEWEB)

Montalvo-Gonzalez, Ruben [Universidad Autonoma de Nayarit, Tepic, Nay (Mexico). Unidad Academica de Ciencias Quimico Biologicas y Farmaceuticas; Chavez, Daniel; Aguirre, Gerardo; Parra-Hake, Miguel; Somanathan, Ratnasamy, E-mail: somanatha@sundown.sdsu.ed [Instituto Tecnologico de Tijuana, B.C. (Mexico). Centro de Graduados e Investigacion

2010-07-01

Two C{sub 2}-symmetric bis(sulfonamide) ligands containing fluorene-chiral (1R, 2R)-cyclohexane-1,2-diamine were complexed to Rh{sup III}(Cp{sup *}) and used as catalyst to reduce aromatic ketones. The corresponding chiral secondary alcohols were obtained in 87-100% ee and 85-99% yield, under asymmetric transfer hydrogenation (ATH) conditions using aqueous sodium formate as the hydride source. With acetophenone, 94% ee and 86-97% yield was achieved with substrate/catalyst (S/C) ratio of 10,000. (author)

Biodegradation of benzalkonium chlorides singly and in mixtures by a Pseudomonas sp. isolated from returned activated sludge

International Nuclear Information System (INIS)

Khan, Adnan Hossain; Topp, Edward; Scott, Andrew; Sumarah, Mark; Macfie, Sheila M.; Ray, Madhumita B.

2015-01-01

Highlights: • Pseudomonas sp. degraded two benzalkonium chlorides: BDDA and BDTA. • Although BDTA biodegraded at low concentration, it inhibited the degradation of BDDA. • For BDDA, two transformation products indicate two sites of bacterial activity. • "1"4C-labelled BDDA was mineralized to "1"4CO_2 within 300 h. - Abstract: Bactericidal cationic surfactants such as quaternary ammonium compounds (QACs) are widely detected in the environment, and found at mg kg"−"1 concentrations in biosolids. Although individual QACs are amenable to biodegradation, it is possible that persistence is increased for mixtures of QACs with varying structure. The present study evaluated the biodegradation of benzyl dimethyl dodecyl ammonium chloride (BDDA) singly and in the presence of benzyl dimethyl tetradecyl ammonium chloride (BDTA) using Pseudomonas sp., isolated from returned activated sludge. Growth was evaluated, as was biodegradation using "1"4C and HPLC-MS methods. BDTA was more toxic to growth of Pseudomonas sp. compared to BDDA, and BDTA inhibited BDDA biodegradation. The benzyl ring of [U-"1"4C-benzyl] BDDA was readily and completely mineralized. The detection of the transformation products benzyl methyl amine and dodecyl dimethyl amine in spent culture liquid was consistent with literature. Overall, this study demonstrates the antagonistic effect of interactions on biodegradation of two widely used QACs suggesting further investigation on the degradation of mixture of QACs in wastewater effluents and biosolids.

Benzo[a]pyrene co-metabolism in the presence of plant root extracts and exudates: Implications for phytoremediation

Energy Technology Data Exchange (ETDEWEB)

Rentz, Jeremy A [Civil and Environmental Engineering, University of Iowa, Iowa City, IA 52242 (United States); Alvarez, Pedro J.J. [Civil and Environmental Engineering, Rice University, Houston, TX 77251 (United States); Schnoor, Jerald L [Civil and Environmental Engineering, University of Iowa, Iowa City, IA 52242 (United States)

2005-08-15

Benzo[a]pyrene, a high molecular weight (HMW) polycyclic aromatic hydrocarbon (PAH) was removed from solution by Sphingomonas yanoikuyae JAR02 while growing on root products as a primary carbon and energy source. Plant root extracts of osage orange (Maclura pomifera), hybrid willow (Salix albaxmatsudana), or kou (Cordia subcordata), or plant root exudates of white mulberry (Morus alba) supported 15-20% benzo[a]pyrene removal over 24 h that was similar to a succinate grown culture and an unfed acetonitrile control. No differences were observed between the different root products tested. Mineralization of {sup 14}C-7-benzo[a]pyrene by S. yanoikuyae JAR02 yielded 0.2 to 0.3% {sup 14}CO{sub 2} when grown with plant root products. Collectively, these observations were consistent with field observations of enhanced phytoremediation of HMW PAH and corroborated the hypothesis that co-metabolism may be a plant/microbe interaction important to rhizoremediation. However, degradation and mineralization was much less for root product-exposed cultures than salicylate-induced cultures, and suggested the rhizosphere may not be an optimal environment for HMW PAH degradation by Sphingomonas yanoikuyae JAR02. - Bacterial benzo[a]pyrene cometabolism, a plant-microbe interaction affecting polycyclic aromatic hydrocarbon phytoremediation was demonstrated with Sphingomonas yanoikuyae JAR02 that utilized plant root extracts and exudates as primary substrates.

Biodegradation of 4-chlorophenol by adsorptive immobilized Alcaligenes sp. A 7-2 in soil.

Science.gov (United States)

Balfanz, J; Rehm, H J

1991-08-01

Alcaligenes sp. A 7-2 immobilized on granular clay has been applied in a percolator to degrade 4-chlorophenol in sandy soil. Good adsorption rates on granular clay were achieved using cell suspensions with high titres and media at pH 8.0. The influence of various parameters such as aeration rate, pH, temperature, concentration of 4-chlorophenol and size of inoculum on the degradation rate were investigated. During fed-batch fermentations under optimal culture conditions, concentrations of 4-chlorophenol up to 160 mg.l-1 could be degraded. Semicontinuous culture experiments demonstrated that the degradation potential in soil could be well established and enhanced by the addition of immobilized bacteria. Continuous fermentation was performed with varying 4-chlorophenol concentrations in the feed and different input levels. The maximum degradation rate was 1.64 g.l-1.day-1.

Desulfotignum toluenicum sp. nov., a novel toluene-degrading, sulphate-reducing bacterium isolated from an oil-reservoir model column.

Science.gov (United States)

Ommedal, Hege; Torsvik, Terje

2007-12-01

A Gram-negative, sulphate-reducing bacterium (strain H3(T)) was isolated from an oil-reservoir model column. The new isolate was able to oxidize toluene coupled to hydrogen sulphide production. For growth, the optimum salt concentration was 1.5 % (w/v), the optimum pH was 7.2 and the optimum temperature was 34 degrees C. The cells were straight to slightly curved rods, 0.6-1.0 microm in diameter and 1.4-2.5 microm in length. The predominant fatty acids were C(16 : 0), C(16 : 1)omega7c and C(17 : 0) cyclo, and the cells also contained dimethylacetals. Cloning and sequencing of a 1505 bp long fragment of the 16S rRNA gene showed that strain H3(T) is a member of the Deltaproteobacteria and is related closely to Desulfotignum balticum DSM 7044(T). The G+C content of the DNA was 52.0 mol% and the DNA-DNA similarity to D. balticum DSM 7044(T) was 56.1 %. Based on differences in DNA sequence and the unique property of toluene degradation, it is proposed that strain H3(T) should be designated a member of a novel species within the genus Desulfotignum, for which the name Desulfotignum toluenicum sp. nov. is proposed. The type strain is H3(T) (=DSM 18732(T)=ATCC BAA-1460(T)).

Potential Marine Fungi Hypocreaceae sp. as Agarase Enzyme to Hydrolyze Macroalgae Gelidium latifolium (Potensi Jamur Hypocreaceae sp. sebagai Enzim Agarase untuk menghidrolisis Makroalga Gelidium latifolium

Directory of Open Access Journals (Sweden)

Mujizat Kawaroe

2015-03-01

Full Text Available Agarase dapat mendegradasi agar ke oligosakarida dan memiliki banyak manfaat untuk makanan, kosmetik, dan lain-lain. Banyak spesies pendegradasi agar adalah organismelaut. Beberapa agarase telah diisolasi dari genera yang berbeda dari mikroorganisme yang ditemukan di air dan sedimen laut. Hypocreaceae sp. diisolasi dari air laut Pulau Pari, Kepulauan Seribu, Jakarta, Indonesia. Berdasarkan hasil identifikasi gen 16S rDNA dari 500 basis pasangan, isolat A10 memiliki 99% kesamaan dengan Hypocreaceae sp. Enzim agarase ekstraseluler dari Hypocreaceae sp. memiliki pH dan suhu optimum pada 8 TrisHCl (0,148 μ.mL-1 dan 50°C (0,182 μ.mL-1, masing-masing. Enzim Agarase dari Hypocreaceae sp. mencapai kondisi optimum pada aktivitas enzim tertinggi selama inkubasi dalam 24 jam (0,323 μ.mL-1. SDS page mengungkapkan bahwa ada dua band dari protein yang dihasilkan oleh agarase dari Hypocreaceae sp. yang berada di berat molekul 39 kDa dan 44 kDa dan hidrolisis Gelidium latifolium diperoleh 0,88% etanol. Kata kunci: enzim agarase, Hypocreaceae sp., hidrolisis, fungi, rDNA. Agarase can degradedagarto oligosaccharide and has a lot of benefits for food, cosmetics, and others. Many species of agar- degrader are marine-organism. Several agarases have been isolated from different genera of microorganisms found in seawater and marine sediments. Hypocreaceae sp. was isolated from sea water of Pari Islands, Seribu Islands, Jakarta, Indonesia. Based on the results of the 16S rDNA gene identification of 500 base pairs, A10 isolates had 99 % similarity toHypocreaceae sp. The extracellular agarase enzyme from Hypocreaceae sp. have optimum pH and temperature at 8 TrisHCl (0.148 µ.mL-1 and 50 °C (0.182 µ.mL-1, respectively. Agarase enzyme of Hypocreaceae sp. reach an optimum condition at the highest enzyme activity during incubation in 24 hours (0.323 µ.mL-1. SDS Page revealed that there are two bands of protein produced by agarase of Hypocreaceae sp. which are at

Isolation and Identification of Carcinogen Acenaphthene-Degrading Endemic Bacteria from Crude Oil Contaminated Soils around Abadan Refinery

Directory of Open Access Journals (Sweden)

Farshid Kafilzadeh

2012-12-01

Full Text Available Background and Objective: PAHs are non-polar organic compounds consisting of two or more fused benzene multi-rings. Among these compounds, acenaphthene is a multi-ring hydrocarbon that occurs abundantly in nature. Use of microorganisms to clean the contaminations of soil can be cheap and effective. The most important acenaphthene-degrading bacteria are pseudomonas, micrococcus, and Bacillus. The goal of this study was to isolate and identify the bacteria which degrade acenaphthene in soils around Abadan Refinery and to investigate the relation between the levels of environmental pollution with acenaphthene. Materials and Methods: Soil samples were collected from three areas around Abadan Refinery. The number of the bacteria was counted on the nutrient agar culture with and without acenaphthene. Isolation of the bacteria was done by culturing the samples on acenaphthene broth with a mineral-salt medium, and on an acenaphthene agar medium. Then, the bacteria were identified via biochemical diagnostic tests. Results: The logarithm average of the bacteria was 4.786 ± 0.073 at a medium with acenaphthene, which was 6.671 ± 0.073 less than that of the control medium. The maximum number of degrading bacteria was 7.089 ± 0.089 at Station C, and the minimum number of the degrading bacteria was 4.485 ± 0.089 at Station B. In this study, Bacillus sp, Micrococcus Luteus, Corynebacterium sp, Staphylococcus epidermidis, and Pseudomonas sp bacteria were isolated and identified in terms of frequency, respectively. Conclusion: The results of this study showed that the soil around Abadan Refinery contained a great number of acenaphthene degrading bacteria, especially Bacillus and Micrococcus.

Effective production of bioenergy from marine Chlorella sp. by high-pressure homogenization

Directory of Open Access Journals (Sweden)

Woon Yong Choi

2016-01-01

Full Text Available This study investigated the use of a high-pressure homogenization process for the production of high shear stress on Chlorella sp. cells in order to effectively degrade their cell walls. The high-pressure homogenization process was conducted by using various pressure conditions in the range of 68.94–275.78 MPa with different numbers of repeated cycles. The optimal high-pressure homogenization pretreatment conditions were found to be two cycles at a pressure of 206.84 MPa, which provided an extraction yield of 20.35% (w/w total cellular lipids. In addition, based on the confocal microscopic images of Chlorella sp. cells stained by using nile red, the walls of Chlorella sp. cells were disrupted more effectively using this process when compared with the disruption achieved by conventional lipid-extraction processes. By using the by-product of Chlorella sp., 47.3% ethanol was obtained from Saccharomyces cerevisiae cultures. These results showed that the high-pressure homogenization process efficiently hydrolysed this marine resource for subsequent bioethanol production by using only water.

Exposure of Cucurbita pepo to DDE-contamination alters the endophytic community: A cultivation dependent vs a cultivation independent approach

International Nuclear Information System (INIS)

Eevers, N.; Hawthorne, J.R.; White, J.C.; Vangronsveld, J.; Weyens, N.

2016-01-01

2,2-bis(p-chlorophenyl)-1,1-dichloro-ethylene (DDE) is the most abundant and persistent degradation product of the pesticide 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) and is encountered in contaminated soils worldwide. Both DDE and DDT are classified as Persistent Organic Pollutants (POPs) due to their high hydrophobicity and potential for bioaccumulation and biomagnification in the food chain. Zucchini (Cucurbita pepo ssp. pepo) has been shown to accumulate high concentrations of DDE and other POPs and has been proposed as a phytoremediation tool for contaminated soils. The endophytic bacteria associated with this plant may play an important role in the remedial process. Therefore, this research focuses on changes in endophytic bacterial communities caused by the exposure of C. pepo to DDE. The total bacterial community was investigated using cultivation-independent 454 pyrosequencing, while the cultivable community was identified using cultivation-dependent isolation procedures. For both procedures, increasing numbers of endophytic bacteria, as well as higher diversities of genera were observed when plants were exposed to DDE. Several bacterial genera such as Stenotrophomonas sp. and Sphingomonas sp. showed higher abundance when DDE was present, while, for example Pseudomonas sp. showed a significantly lower abundance in the presence of DDE. These findings suggest tolerance of different bacterial strains to DDE, which might be incorporated in further investigations to optimize phytoremediation with the possible use of DDE-degrading endophytes. - Highlights: • Cucurbita pepo accumulates DDE and can be used for phytoremediation. • Phytoremediation capacity might be enhanced with endophytic bacteria. • The differences in bacterial communities without and with DDE are investigated. • Several DDE-tolerant bacteria are discovered and might be used in phytoremediation. - DDE-exposure and DDE-uptake of Cucurbita pepo lead to increases in both diversity

Ecofriendly biodegradation and detoxification of Reactive Red 2 textile dye by newly isolated Pseudomonas sp. SUK1

International Nuclear Information System (INIS)

Kalyani, D.C.; Telke, A.A.; Dhanve, R.S.; Jadhav, J.P.

2009-01-01

The aim of this work is to evaluate textile dyes degradation by novel bacterial strain isolated from the waste disposal sites of local textile industries. Detailed taxonomic studies identified the organisms as Pseudomonas species and designated as strain Pseudomonas sp. SUK1. The isolate was able to decolorize sulfonated azo dye (Reactive Red 2) in a wide range (up to 5 g l -1 ), at temperature 30 deg. C, and pH range 6.2-7.5 in static condition. This isolate also showed decolorization of the media containing a mixture of dyes. Measurements of COD were done at regular intervals to have an idea of mineralization, showing 52% reduction in the COD within 24 h. Induction in the activity of lignin peroxidase and azoreductase was observed during decolorization of Reactive Red 2 in the batch culture, which represented their role in degradation. The biodegradation was monitored by UV-vis, IR spectroscopy, HPLC. The final product, 2-naphthol was characterized by GC-mass spectroscopy. The phytotoxicity study revealed the degradation of Reactive Red 2 into non-toxic product by Pseudomonas sp. SUK1

Paraburkholderia aromaticivorans sp. nov., an aromatic hydrocarbon-degrading bacterium, isolated from gasoline-contaminated soil.

Science.gov (United States)

Lee, Yunho; Jeon, Che Ok

2018-04-01

A Gram-stain-negative, facultatively aerobic, aromatic hydrocarbon-degrading bacterium, designated strain BN5 T , was isolated from gasoline-contaminated soil. Cells were motile and slightly curved rods with a single flagellum showing catalase and oxidase activities. Growth was observed at 20-37 °C (optimum, 25-30 °C), pH 3-7 (optimum, pH 5-6) and 0-2 % NaCl (optimum, 0 %). Ubiquinone-8 was the predominant respiratory quinone. The major fatty acids were C16 : 0, cyclo-C19 : 0ω8c and summed feature 8 (comprising C18 : 1ω7c and/or C18 : 1ω6c). Diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified phosphoamino lipid, three unidentified amino lipids and eight unidentified lipids were the identified polar lipids. The DNA G+C content was 62.93 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain BN5 T formed a phylogenic lineage with members of the genus Paraburkholderia and showed the highest 16S rRNA gene sequence similarities to Paraburkholderia phytofirmans PsJN T (99.4 %), Paraburkholderia dipogonis DL7 T (98.8 %) and Paraburkholderia insulsa PNG-April T (98.8 %). The average nucleotide identity and in silico DNA-DNA hybridization (DDH) values between strain BN5 T and P. phytofirmans PsJN T were 88.5 and 36.5 %, respectively. The DDH values for strain BN5 T with P. dipogonis LMG 28415 T and P. insulsa DSM 28142 T were 41.0±4.9 % (reciprocal, 33.0±4.3 %) and 47.1±6.6 % (reciprocal, 51.7±5.4 %), respectively. Based on its physiological, chemotaxonomic and phylogenetic features, we conclude that strain BN5 T is a novel species of the genus Paraburkholderia, for which the name Paraburkholderia aromaticivorans sp. nov. is proposed. The type strain is BN5 T (=KACC 19419 T =JCM 32303 T ).

Biodegradation of benzalkonium chlorides singly and in mixtures by a Pseudomonas sp. isolated from returned activated sludge

Energy Technology Data Exchange (ETDEWEB)

Khan, Adnan Hossain, E-mail: akhan462@uwo.ca [Department of Chemical and Biochemical Engineering, University of Western Ontario, London, ON N6A 5B9 (Canada); Topp, Edward, E-mail: Ed.Topp@AGR.GC.CA [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Department of Biology, University of Western Ontario, London, ON N6A 5B7 (Canada); Scott, Andrew, E-mail: Andrew.Scott@AGR.GC.CA [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Sumarah, Mark, E-mail: Mark.Sumarah@agr.gc.ca [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Macfie, Sheila M., E-mail: smacfie@uwo.ca [Department of Biology, University of Western Ontario, London, ON N6A 5B7 (Canada); Ray, Madhumita B., E-mail: mbhowmic@uwo.ca [Department of Chemical and Biochemical Engineering, University of Western Ontario, London, ON N6A 5B9 (Canada)

2015-12-15

Highlights: • Pseudomonas sp. degraded two benzalkonium chlorides: BDDA and BDTA. • Although BDTA biodegraded at low concentration, it inhibited the degradation of BDDA. • For BDDA, two transformation products indicate two sites of bacterial activity. • {sup 14}C-labelled BDDA was mineralized to {sup 14}CO{sub 2} within 300 h. - Abstract: Bactericidal cationic surfactants such as quaternary ammonium compounds (QACs) are widely detected in the environment, and found at mg kg{sup −1} concentrations in biosolids. Although individual QACs are amenable to biodegradation, it is possible that persistence is increased for mixtures of QACs with varying structure. The present study evaluated the biodegradation of benzyl dimethyl dodecyl ammonium chloride (BDDA) singly and in the presence of benzyl dimethyl tetradecyl ammonium chloride (BDTA) using Pseudomonas sp., isolated from returned activated sludge. Growth was evaluated, as was biodegradation using {sup 14}C and HPLC-MS methods. BDTA was more toxic to growth of Pseudomonas sp. compared to BDDA, and BDTA inhibited BDDA biodegradation. The benzyl ring of [U-{sup 14}C-benzyl] BDDA was readily and completely mineralized. The detection of the transformation products benzyl methyl amine and dodecyl dimethyl amine in spent culture liquid was consistent with literature. Overall, this study demonstrates the antagonistic effect of interactions on biodegradation of two widely used QACs suggesting further investigation on the degradation of mixture of QACs in wastewater effluents and biosolids.

Microbial degradation of resins fractionated from Arabian light crude oil

International Nuclear Information System (INIS)

Venkateswaran, K.; Hoaki, T.; Kato, M.; Maruyama, T.

1995-01-01

Sediment samples from the Japanese coasts were screened for microorganisms able to degrade resin components of crude oil. A mixed population that could degrade 35% of 5000 ppm resin in 15 days was obtained. This population also metabolized 50% of saturates and aromatics present in crude oil (5000 ppm) in 7 days. A Pseudomonas sp., isolated from the mixed population, emulsified and degraded 30% of resins. It also degraded saturates and aromatics (30%) present in crude oil (5000 ppm). These results were obtained from Iatroscan analysis. Degradation of crude oil was also analyzed by gas chromatography (GC). The peaks corresponding to known aliphatic hydrocarbons in crude oil greatly decreased within the first two days of incubation in the cultures of the RY-mixed population and of Pseudomonas strain UN3. Aromatic compounds detected as a broad peak by GC were significantly degraded at day 7 by Pseudomonas strain UN3, and at day 15 by the RY-mixed population. Investigations are ongoing to determine the genetic basis for the ability of these organisms to grow on the resin fractions of crude oil as a sole source of carbon and energy. 28 refs., 4 figs., 1 tab

Gelria glutamica gen. nov., sp. a thermophilic oligately syntrophic glutamate-degrading anaerobe

NARCIS (Netherlands)

Plugge, C.M.; Balk, M.; Zoetendal, E.G.; Stams, A.J.M.

2002-01-01

A novel anaerobic, Gram-positive, thermophilic, spore-forming, obligately syntrophic, glutamate-degrading bacterium, strain TGO(T), was isolated from a propionate-oxidizing methanogenic enrichment culture. The axenic culture was obtained by growing the bacterium on pyruvate. Cells were rod-shaped

Crystallization of Spätzle, a cystine-knot protein involved in embryonic development and innate immunity in Drosophila melanogaster

Energy Technology Data Exchange (ETDEWEB)

Hoffmann, Anita; Neumann, Piotr [Institut für Biochemie und Biotechnologie, Martin-Luther-Universität Halle-Wittenberg, Abteilung Physikalische Biotechnologie, Kurt-Mothes-Strasse 3, 06120 Halle (Saale) (Germany); Schierhorn, Angelika [Max-Planck-Institut für Proteinfaltung, Abteilung Massenspektrometrie, Kurt-Mothes-Strasse 3, 06120 Halle (Saale) (Germany); Stubbs, Milton T., E-mail: stubbs@biochemtech.uni-halle.de [Institut für Biochemie und Biotechnologie, Martin-Luther-Universität Halle-Wittenberg, Abteilung Physikalische Biotechnologie, Kurt-Mothes-Strasse 3, 06120 Halle (Saale) (Germany); Mitteldeutsches Zentrum für Struktur und Dynamik der Proteine (MZP), Martin-Luther-Universität Halle-Wittenberg (Germany)

2008-08-01

Crystallization of the cystine-knot protein Spätzle occurred following serendipitous limited degradation of the pro-Spätzle propeptide during the crystallization experiment. The Spätzle protein is involved in both the definition of the dorsal–ventral axis during embryonic development and in the adult innate immune response. The disulfide-linked dimeric cystine-knot protein has been expressed as a proprotein in inclusion bodies in Escherichia coli and refolded in vitro by rapid dilution. Initial orthorhombic crystals that diffracted to 7 Å resolution were obtained after three months by the sitting-drop vapour-diffusion method. Optimization of the crystallization conditions resulted in orthorhombic crystals (space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 53.0, b = 59.2, c = 62.5 Å) that diffracted to 2.8 Å resolution in-house. The small volume of the asymmetric unit indicated that it was not possible for the crystals to contain the complete pro-Spätzle dimer. Mass spectrometry, N-terminal sequencing and Western-blot analysis revealed that the crystals contained the C-terminal disulfide-linked cystine-knot dimer. Comparison of various crystallization experiments indicated that degradation of the N-terminal prodomain was dependent on the buffer conditions.

Potential use of soil-born fungi isolated from treated soil in Indonesia to degrade glyphosate herbicide

Directory of Open Access Journals (Sweden)

N. Arfarita

2014-01-01

Full Text Available The glyphosate herbicide is the most common herbicides used in palm-oil plantations and other agricultural in Indonesial. In 2020, Indonesian government to plan the development of oil palm plantations has reached 20 million hectares of which now have reached 6 million hectares. It means that a huge chemicals particularly glyphosate has been poured into the ground and continues to pollute the soil. However, there is no report regarding biodegradation of glyphosate-contaminated soils using fungal strain especially in Indonesia. This study was to observe the usage of Round Up as selection agent for isolation of soil-born fungi capable to grow on glyphosate as a sole source of phosphorus. Five fungal strains were able to grow consistently in the presence of glyphosate as the sole phosphorus source and identified as Aspergillus sp. strain KRP1, Fusarium sp. strain KRP2, Verticillium sp. strain KRP3, Acremoniumsp. strain GRP1 and Scopulariopsis sp. strain GRP2. This indicates as their capability to utilize and degrade this herbicide. We also used standard medium as control and get seventeen fungal strains. The seventeen fungal strains were identified as species of Botrytis, Fusarium, Aspergillus, Penicillium, Verticillium, Trichoderma and Paecilomyces. These results show the reduction in the number of fungal strains on solid medium containing glyphosate. Of the five isolated fungal species, Verticillium sp. strain KRP3 and Scopulariopsis sp. strain GRP2 were selected for further study based on their highest ratio of growth diameter. This study indicates that treatment of soil with glyphosate degrading fungus would be useful in some areas where this herbicide is extensively used.

The insulin radioimmunoassay kit prepared by IPEN-CNEN/SP - Brazil

International Nuclear Information System (INIS)

Mesquita, C.H. de; Silva, C.P.G. da; Hamada, M.M.

1985-11-01

The specification and methodological aspects of the insulin radioimmunoassay kit produced by IPEN-CNEN/SP - Brazil are described. The limitations taking care and the following quality control parameters or procedures are discussed: specific radioactivity, comparison between two insulin - 125 I purification procedures, affinity constant 'K' of the antigen - antibody reaction, minimal detectable dose (MDD), kinetics degradation of the radioinsulin, radioassay imprecision profile, radioassay performance temperature dependence and normal values histogram. (Author) [pt

Spectroscopic investigation of the interfaces in new poly(9,9-dihexyl–9H-fluorene-2,7- diyl based electroluminescent devices

Directory of Open Access Journals (Sweden)

C. Donitsi

2014-01-01

Full Text Available The highest occupied and lowest unoccupied states of the new electroluminescent material poly(9,9-dihexyl–9H- fluorene-2,7-diyl (PPV-D and polyvinylcarbazole (PVK are investigated using ultraviolet photoelectron and inverse photoemission spectroscopies. Hole injection barriers are determined for interfaces between indium-tin oxide covered substrates with work function ranging from 4.4 to 4.7 eV and these two polymers. Vacuum level alignment with flat bands away from the interface is found when the interface hole barrier is 0.6 eV or larger. Band bending away from the Fermi level occurs when the hole barrier is smaller than 0.6 eV. This is due to the accumulation charges at the interface with the polymer when the injection barrier is small. The resulting field bends the polymer levels to limit charge incoming in the bulk of the film. The efficiency of the electroluminescent structures is strongly influenced by the different energy levels alignment at the layer interfaces.

Reductive dehalogenation of 3,5-dibromo-4-hydroxybenzoate by an aerobic strain of Delftia sp. EOB-17.

Science.gov (United States)

Chen, Kai; Jian, Shanshan; Huang, Linglong; Ruan, Zhepu; Li, Shunpeng; Jiang, Jiandong

2015-12-01

To confirm the reductive dehalogenation ability of the aerobic strain of Delftia sp. EOB-17, finding more evidences to support the hypothesis that reductive dehalogenation may occur extensively in aerobic bacteria. Delftia sp. EOB-17, isolated from terrestrial soil contaminated with halogenated aromatic compounds, completely degraded 0.2 mM DBHB in 28 h and released two equivalents of bromides under aerobic conditions in the presence of sodium succinate. LC-MS analysis revealed that DBHB was transformed to 4-hydroxybenzoate via 3-bromo-4-hydroxybenzoate by successive reductive dehalogenation. Highly conserved DBHB-degrading genes, including reductive dehalogenase gene (bhbA3) and the extra-cytoplasmic binding receptor gene (bhbB3), were also found in strain EOB-17 by genome sequencing. The optimal temperature and pH for DBHB reductive dehalogenation activity are 30 °C and 8, respectively, and 0.1 mM Cd(2+), Cu(2+), Hg(2+) and Zn(2+) strongly inhibited dehalogenation activity. The aerobic strain of Delftia sp. EOB-17 was confirmed to reductively dehalogenate DBHB under aerobic conditions, providing another evidence to support the hypothesis that reductive dehalogenation occurs extensively in aerobic bacteria.

Characterization and role of a metalloprotease induced by chitin in Serratia sp. KCK.

Science.gov (United States)

Kim, Hyun-Soo; Golyshin, Peter N; Timmis, Kenneth N

2007-11-01

A metalloprotease induced by chitin in a new chitinolytic bacterium Serratia sp. Strain KCK was purified and characterized. Compared with other Serratia enzymes, it exhibited a rather broad pH activity range (pH 5.0-8.0), and thermostability. The cognate ORF, mpr, was cloned and expressed. Its deduced amino acid sequence showed high similarity to those of bacterial zinc-binding metalloproteases and a well-conserved serralysin family motif. Pretreatment of chitin with the Mpr protein promoted chitin degradation by chitinase A, which suggests that Mpr participates in, and facilitates, chitin degradation by this microorganism.

Fundamental and future prospects of printed ambipolar fluorene-type polymer light-emitting transistors for improved external quantum efficiency, mobility, and emission pattern

Science.gov (United States)

Kajii, Hirotake

2018-05-01

In this review, we focus on the improved external quantum efficiency, field-effect mobility, and emission pattern of top-gate-type polymer light-emitting transistors (PLETs) based on ambipolar fluorene-type polymers. A low-temperature, high-efficiency, printable red phosphorescent PLET based on poly(alkylfluorene) with modified alkyl side chains fabricated by a film transfer process is demonstrated. Device fabrication based on oriented films leads to an improved EL intensity owing to the increase in field-effect mobility. There are three factors that affect the transport of carriers, i.e., the energy level, threshold voltage, and mobility of each layer for heterostructure PLETs, which result in various emission patterns such as the line-shaped, multicolor and in-plane emission pattern in the full-channel area between source and drain electrodes. Fundamentals and future prospects in heterostructure devices are discussed and reviewed.

Global microarray analysis of carbohydrate use in alkaliphilic hemicellulolytic bacterium Bacillus sp. N16-5.

Directory of Open Access Journals (Sweden)

Yajian Song

Full Text Available The alkaliphilic hemicellulolytic bacterium Bacillus sp. N16-5 has a broad substrate spectrum and exhibits the capacity to utilize complex carbohydrates such as galactomannan, xylan, and pectin. In the monosaccharide mixture, sequential utilization by Bacillus sp. N16-5 was observed. Glucose appeared to be its preferential monosaccharide, followed by fructose, mannose, arabinose, xylose, and galactose. Global transcription profiles of the strain were determined separately for growth on six monosaccharides (glucose, fructose, mannose, galactose, arabinose, and xylose and four polysaccharides (galactomannan, xylan, pectin, and sodium carboxymethylcellulose using one-color microarrays. Numerous genes potentially related to polysaccharide degradation, sugar transport, and monosaccharide metabolism were found to respond to a specific substrate. Putative gene clusters for different carbohydrates were identified according to transcriptional patterns and genome annotation. Identification and analysis of these gene clusters contributed to pathway reconstruction for carbohydrate utilization in Bacillus sp. N16-5. Several genes encoding putative sugar transporters were highly expressed during growth on specific sugars, suggesting their functional roles. Two phosphoenolpyruvate-dependent phosphotransferase systems were identified as candidate transporters for mannose and fructose, and a major facilitator superfamily transporter was identified as a candidate transporter for arabinose and xylose. Five carbohydrate uptake transporter 1 family ATP-binding cassette transporters were predicted to participate in the uptake of hemicellulose and pectin degradation products. Collectively, microarray data improved the pathway reconstruction involved in carbohydrate utilization of Bacillus sp. N16-5 and revealed that the organism precisely regulates gene transcription in response to fluctuations in energy resources.

Global Microarray Analysis of Carbohydrate Use in Alkaliphilic Hemicellulolytic Bacterium Bacillus sp. N16-5

Science.gov (United States)

Song, Yajian; Xue, Yanfen; Ma, Yanhe

2013-01-01

The alkaliphilic hemicellulolytic bacterium Bacillus sp. N16-5 has a broad substrate spectrum and exhibits the capacity to utilize complex carbohydrates such as galactomannan, xylan, and pectin. In the monosaccharide mixture, sequential utilization by Bacillus sp. N16-5 was observed. Glucose appeared to be its preferential monosaccharide, followed by fructose, mannose, arabinose, xylose, and galactose. Global transcription profiles of the strain were determined separately for growth on six monosaccharides (glucose, fructose, mannose, galactose, arabinose, and xylose) and four polysaccharides (galactomannan, xylan, pectin, and sodium carboxymethylcellulose) using one-color microarrays. Numerous genes potentially related to polysaccharide degradation, sugar transport, and monosaccharide metabolism were found to respond to a specific substrate. Putative gene clusters for different carbohydrates were identified according to transcriptional patterns and genome annotation. Identification and analysis of these gene clusters contributed to pathway reconstruction for carbohydrate utilization in Bacillus sp. N16-5. Several genes encoding putative sugar transporters were highly expressed during growth on specific sugars, suggesting their functional roles. Two phosphoenolpyruvate-dependent phosphotransferase systems were identified as candidate transporters for mannose and fructose, and a major facilitator superfamily transporter was identified as a candidate transporter for arabinose and xylose. Five carbohydrate uptake transporter 1 family ATP-binding cassette transporters were predicted to participate in the uptake of hemicellulose and pectin degradation products. Collectively, microarray data improved the pathway reconstruction involved in carbohydrate utilization of Bacillus sp. N16-5 and revealed that the organism precisely regulates gene transcription in response to fluctuations in energy resources. PMID:23326578

Isolation and application of hydrocarbon degradation of indigenous microbial from oil contaminated soil

International Nuclear Information System (INIS)

Dadang Sudrajat; Nana Mulyana; Tri Retno DL

2015-01-01

The aims of this research are to obtain indigenous potential microbes from bacterial and fungal groups which have capable of degrading hydrocarbon from crude oil contaminated soil. The research carried out were isolation, selection, and identification potential microbial isolates capable of degrading hydrocarbon from oil contaminated soil located at Cepu East Java. The isolates were tested for their growth and ability to degrades crude oil. Each isolate was inoculated unto minimum mineral salt medium (MSM) contained 1% crude oil. Viability and stability test of selected isolates were carried out on irradiated compost carrier materials contained 5% crude oil. The fours series microbial s consortium consists of microbial consortium I, II, III, and IV were tested for the in vitro biodegradability of hydrocarbon. The results shows there sixty two (62) isolates are obtained, among them 42 bacteria and 20 molds. From 42 bacterial isolates, only 8 strains were potent hydrocarbon degraders. Three of these isolates are identified Bacillus cereus (BMC2), Bacillus sp (BMC4), and Pseudomonas sp (BMC6). Whereas from 20 fungal isolates, only 4 strains were potent hydrocarbon degraders. Two of these isolates are identified Aspergillus fumigatus (FMC2) and Aspergillus niger (FMC6). All isolates show good growth in mineral salt medium contained crude oil with decrease in pH. The ability of decrease of TPH content by the bacterial and fungal isolates were 54, 61, 67, 74, and 78% respectively at day 30. The viability and stability of microbial isolates show considerable good viability on irradiated compost carrier materials after 14 days storage. From the fours series microbial consortium, the highest TPH degradation rates is found in microbial consortium III (BMC6, BMC2, and FMC6) with 89,1% in 5 weeks. (author)

Novel diesel-oil-degrading bacteria and fungi from the Ecuadorian Amazon rainforest.

Science.gov (United States)

Maddela, N R; Masabanda, M; Leiva-Mora, M

2015-01-01

Isolating new diesel-oil-degrading microorganisms from crude-oil contaminated sites and evaluating their degradation capacities are vitally important in the remediation of oil-polluted environments and crude-oil exploitation. In this research, new hydrocarbon-degrading bacteria and fungi were isolated from the crude-oil contaminated soil of the oil-fields in the Amazon rainforest of north-east Ecuador by using a soil enrichment technique. Degradation analysis was tracked by gas chromatography and a flame ionization detector. Under laboratory conditions, maximum degradability of the total n-alkanes reached up to 77.34 and 62.62 removal ratios after 30 days of incubation for the evaporated diesel oil by fungi (isolate-1) and bacteria (isolate-1), respectively. The 16S/18S rDNA sequence analysis indicated that the microorganisms were most closely (99-100%) related to Bacillus cereus (isolate-1), Bacillus thuringiensis (isolate-2), Geomyces pannorum (isolate-1), and Geomyces sp. (isolate-2). Therefore, these strains enable the degradation of hydrocarbons as the sole carbon source, and these findings will benefit these strains in the remediation of oil-polluted environments and oil exploitation.

Identification and production of bioflocculants by Enterobacter sp. and Bacillus sp. and their characterization studies.

Science.gov (United States)

Muthulakshmi, L; Nellaiah, H; Kathiresan, T; Rajini, N; Christopher, Fenila

2017-05-28

In this work, two bioflocculants, namely, EB-EPS and B1-EPS, were derived from Enterobacter sp. and Bacillus sp., respectively, and analyzed with regard to their production and characterization. About 0.9 and 0.16 g of purified EB and B1 were obtained from I L of fermentation broth. Chemical analysis showed the contents of purified EB and B1 mainly as 88.7 and 92.8% (w/w) of carbohydrate, and 11.3 and 21.8% (w/w) protein, respectively. Fourier-transform infrared spectrometry analysis revealed the presence of hydroxyl, amide, and carboxyl groups in the identified bioflocculant. Thermogravimetric analysis (TGA) results exhibited enhanced thermal stability with a minimum mass loss of 50% while 25% were found to have occurred at higher temperatures (>400°C) for microbe-derived compounds EB and B1 leading to the possibility of using these compounds as fillers or for fabricating composite films for high-temperature applications. Further, the compounds from both the bacteria exhibited good antibacterial characteristics against pathogenic Escherichia coli. Degradability study of bioflocculant-embedded composite films shows the possibility of attaining eco-friendly bioremediation. Accordingly, experimental results revealed the suitability of developed composite films as a suitable alternative for food packaging and biomedical applications.

Expression of Heterologous Cellulases in Thermotoga sp. Strain RQ2

Directory of Open Access Journals (Sweden)

Hui Xu

2015-01-01

Full Text Available The ability of Thermotoga spp. to degrade cellulose is limited due to a lack of exoglucanases. To address this deficiency, cellulase genes Csac_1076 (celA and Csac_1078 (celB from Caldicellulosiruptor saccharolyticus were cloned into T. sp. strain RQ2 for heterologous overexpression. Coding regions of Csac_1076 and Csac_1078 were fused to the signal peptide of TM1840 (amyA and TM0070 (xynB, resulting in three chimeric enzymes, namely, TM1840-Csac_1078, TM0070-Csac_1078, and TM0070-Csac_1076, which were carried by Thermotoga-E. coli shuttle vectors pHX02, pHX04, and pHX07, respectively. All three recombinant enzymes were successfully expressed in E. coli DH5α and T. sp. strain RQ2, rendering the hosts with increased endo- and/or exoglucanase activities. In E. coli, the recombinant enzymes were mainly bound to the bacterial cells, whereas in T. sp. strain RQ2, about half of the enzyme activities were observed in the culture supernatants. However, the cellulase activities were lost in T. sp. strain RQ2 after three consecutive transfers. Nevertheless, this is the first time heterologous genes bigger than 1 kb (up to 5.3 kb in this study have ever been expressed in Thermotoga, demonstrating the feasibility of using engineered Thermotoga spp. for efficient cellulose utilization.

Molecular Analysis of Bacterial Communities in Biofilms of a Drinking Water Clearwell

Science.gov (United States)

Zhang, Minglu; Liu, Wenjun; Nie, Xuebiao; Li, Cuiping; Gu, Junnong; Zhang, Can

2012-01-01

Microbial community structures in biofilms of a clearwell in a drinking water supply system in Beijing, China were examined by clone library, terminal restriction fragment length polymorphism (T-RFLP) and 454 pyrosequencing of the amplified 16S rRNA gene. Six biofilm samples (designated R1–R6) collected from six locations (upper and lower sites of the inlet, middle and outlet) of the clearwell revealed similar bacterial patterns by T-RFLP analysis. With respect to the dominant groups, the phylotypes detected by clone library and T-RFLP generally matched each other. A total of 9,543 reads were obtained from samples located at the lower inlet and the lower outlet sites by pyrosequencing. The bacterial diversity of the two samples was compared at phylum and genus levels. Alphaproteobacteria dominated the communities in both samples and the genus of Sphingomonas constituted 75.1%–99.6% of this phylum. A high level of Sphingomonas sp. was first observed in the drinking water biofilms with 0.6–1.0 mg L−1 of chlorine residual. Disinfectant-resistant microorganisms deserve special attention in drinking water management. This study provides novel insights into the microbial populations in drinking water systems and highlights the important role of Sphingomonas species in biofilm formation. PMID:23059725

Characterization of acetanilide herbicides degrading bacteria isolated from tea garden soil.

Science.gov (United States)

Wang, Yei-Shung; Liu, Jian-Chang; Chen, Wen-Ching; Yen, Jui-Hung

2008-04-01

Three different green manures were added to the tea garden soils separately and incubated for 40 days. After, incubation, acetanilide herbicides alachlor and metolachlor were spiked into the soils, separately, followed by the isolation of bacteria in each soil at designed intervals. Several bacterial strains were isolated from the soils and identified as Bacillus silvestris, B. niacini, B. pseudomycoides, B. cereus, B. thuringiensis, B. simplex, B. megaterium, and two other Bacillus sp. (Met1 and Met2). Three unique strains with different morphologies were chosen for further investigation. They were B. megaterium, B. niacini, and B. silvestris. The isolated herbicide-degrading bacteria showed optimal performance among three incubation temperatures of 30 degrees C and the best activity in the 10 to 50 microg/ml concentration of the herbicide. Each bacterial strain was able to degrade more than one kind of test herbicides. After incubation for 119 days, B. cereus showed the highest activity to degrade alachlor and propachlor, and B. thuringiensis to degrade metolachlor.

Diazinon degradation by a novel strain Ralstonia sp. DI-3 and X-ray ...

Indian Academy of Sciences (India)

2016-06-25

Jun 25, 2016 ... vegetables, grains and other foods products. The residues of ... 2007). Degradation products of diazinon include diazoxon, a toxic metabolite, ..... Research Innovation Team of Anhui Province—Ecological. Restoration and ...

Biodegradation of di-n-Butyl Phthalate by Achromobacter sp. Isolated from Rural Domestic Wastewater

Directory of Open Access Journals (Sweden)

Decai Jin

2015-10-01

Full Text Available A bacterial strain W-1, isolated from rural domestic wastewater, can utilize the environmental hormone di-n-butyl phthalate (DBP as the sole carbon and energy source. The isolated bacterium species was confirmed to belong to the genus Achromobacter based on its 16S rRNA gene sequence. The results of substrate utilization tests showed that the strain W-1 could utilize other common phthalates and phenol. High-performance liquid chromatography analysis revealed that the optimal conditions for DBP degradation were pH 7.0, 35 °C, and an agitation rate of 175 rpm. Under these conditions, 500 mg/L of DBP was completely degraded within 30 h. The effects of heavy metals (50 mg/L Cu2+ and 500 mg/L Pb2+ and surfactants (100 mg/L SDS and 500 mg/L Tween 20 on DBP degradation were investigated. The results demonstrated that Cu2+ and SDS severely inhibited DBP degradation and Pb2+ weakly inhibited DBP degradation, while Tween 20 greatly enhanced DBP degradation. Furthermore, phthalate degradation genes were found to be located on a plasmid present in Achromobacter sp. W-1.

Transcriptome and membrane fatty acid analyses reveal different strategies for responding to permeating and non-permeating solutes in the bacterium Sphingomonas wittichii

Directory of Open Access Journals (Sweden)

Johnson David R

2011-11-01

Full Text Available Abstract Background Sphingomonas wittichii strain RW1 can completely oxidize dibenzo-p-dioxins and dibenzofurans, which are persistent contaminants of soils and sediments. For successful application in soil bioremediation systems, strain RW1 must cope with fluctuations in water availability, or water potential. Thus far, however, little is known about the adaptive strategies used by Sphingomonas bacteria to respond to changes in water potential. To improve our understanding, strain RW1 was perturbed with either the cell-permeating solute sodium chloride or the non-permeating solute polyethylene glycol with a molecular weight of 8000 (PEG8000. These solutes are assumed to simulate the solute and matric components of the total water potential, respectively. The responses to these perturbations were then assessed and compared using a combination of growth assays, transcriptome profiling, and membrane fatty acid analyses. Results Under conditions producing a similar decrease in water potential but without effect on growth rate, there was only a limited shared response to perturbation with sodium chloride or PEG8000. This shared response included the increased expression of genes involved with trehalose and exopolysaccharide biosynthesis and the reduced expression of genes involved with flagella biosynthesis. Mostly, the responses to perturbation with sodium chloride or PEG8000 were very different. Only sodium chloride triggered the increased expression of two ECF-type RNA polymerase sigma factors and the differential expression of many genes involved with outer membrane and amino acid metabolism. In contrast, only PEG8000 triggered the increased expression of a heat shock-type RNA polymerase sigma factor along with many genes involved with protein turnover and repair. Membrane fatty acid analyses further corroborated these differences. The degree of saturation of membrane fatty acids increased after perturbation with sodium chloride but had the

Genome Analysis of Fimbriiglobus ruber SP5T, a Planctomycete with Confirmed Chitinolytic Capability.

Science.gov (United States)

Ravin, Nikolai V; Rakitin, Andrey L; Ivanova, Anastasia A; Beletsky, Alexey V; Kulichevskaya, Irina S; Mardanov, Andrey V; Dedysh, Svetlana N

2018-04-01

Members of the bacterial order Planctomycetales have often been observed in associations with Crustacea. The ability to degrade chitin, however, has never been reported for any of the cultured planctomycetes although utilization of N -acetylglucosamine (GlcNAc) as a sole carbon and nitrogen source is well recognized for these bacteria. Here, we demonstrate the chitinolytic capability of a member of the family Gemmataceae , Fimbriiglobus ruber SP5 T , which was isolated from a peat bog. As revealed by metatranscriptomic analysis of chitin-amended peat, the pool of 16S rRNA reads from F. ruber increased in response to chitin availability. Strain SP5 T displayed only weak growth on amorphous chitin as a sole source of carbon but grew well with chitin as a source of nitrogen. The genome of F. ruber SP5 T is 12.364 Mb in size and is the largest among all currently determined planctomycete genomes. It encodes several enzymes putatively involved in chitin degradation, including two chitinases affiliated with the glycoside hydrolase (GH) family GH18, GH20 family β- N -acetylglucosaminidase, and the complete set of enzymes required for utilization of GlcNAc. The gene encoding one of the predicted chitinases was expressed in Escherichia coli , and the endochitinase activity of the recombinant enzyme was confirmed. The genome also contains genes required for the assembly of type IV pili, which may be used to adhere to chitin and possibly other biopolymers. The ability to use chitin as a source of nitrogen is of special importance for planctomycetes that inhabit N-depleted ombrotrophic wetlands. IMPORTANCE Planctomycetes represent an important part of the microbial community in Sphagnum -dominated peatlands, but their potential functions in these ecosystems remain poorly understood. This study reports the presence of chitinolytic potential in one of the recently described peat-inhabiting members of the family Gemmataceae , Fimbriiglobus ruber SP5 T This planctomycete uses

Methanogenic degradation of acetone by an enrichment culture

OpenAIRE

Platen, Harald; Schink, Bernhard

1987-01-01

An anaerobic enrichment culture degraded 1 mol of acetone to 2 tool of methane and 1 tool of carbon dioxide. Two microorganisms were involved in this process, a filament-forming rod similar to Methanothrix sp. and an unknown rod with round to slightly pointed ends. Both organisms formed aggregates up to 300 gm in diameter. No fluorescing bacteria were observed indicating that hydrogen or formate-utilizing methanogens are not involved in this process. Acetate was utilized in this culture by th...

Response characteristics of vegetation and soil environment to permafrost degradation in the upstream regions of the Shule River Basin

International Nuclear Information System (INIS)

Chen Shengyun; Liu Wenjie; Qin Xiang; Liu Yushuo; Ren Jiawen; Qin Dahe; Zhang Tongzuo; Hu Fengzu; Chen Kelong

2012-01-01

Permafrost degradation exhibits striking and profound influences on the alpine ecosystem, and response characteristics of vegetation and soil environment to such degradation inevitably differ during the entire degraded periods. However, up to now, the related research is lacking in the Qinghai–Tibetan Plateau (QTP). For this reason, twenty ecological plots in the different types of permafrost zones were selected in the upstream regions of the Shule River Basin on the northeastern margin of the QTP. Vegetation characteristics (species diversity, community coverage and biomass etc) and topsoil environment (temperature (ST), water content (SW), mechanical composition (SMC), culturable microorganism (SCM), organic carbon (SOC) and total nitrogen (TN) contents and so on), as well as active layer thickness (ALT) were investigated in late July 2009 and 2010. A spatial–temporal shifts method (the spatial pattern that is represented by different types of permafrost shifting to the temporal series that stands for different stages of permafrost degradation) has been used to discuss response characteristics of vegetation and topsoil environment throughout the entire permafrost degradation. The results showed that (1) ST of 0–40 cm depth and ALT gradually increased from highly stable and stable permafrost (H-SP) to unstable permafrost (UP). SW increased initially and then decreased, and SOC content and the quantities of SCM at a depth of 0–20 cm first decreased and then increased, whereas TN content and SMC showed obscure trends throughout the stages of permafrost degradation with a stability decline from H-SP to extremely unstable permafrost (EUP); (2) further, species diversity, community coverage and biomass first increased and then decreased in the stages from H-SP to EUP; (3) in the alpine meadow ecosystem, SOC and TN contents increased initially and then decreased, soil sandy fractions gradually increased with stages of permafrost degradation from substable (SSP

Isolation and characterization of a furfural-degrading bacterium Bacillus cereus sp. strain DS1.

Science.gov (United States)

Zheng, Dan; Bao, Jianguo; Lu, Jueming; Gao, Chunlei

2015-02-01

Furfural was found to be the main organic pollutant in the wastewater coming from the Diosgenin factory. This substance is derived from acidic pentosan in Dioscorea zingiberensis and is also found in a variety of agricultural byproducts, including corncobs, oat, wheat bran, and sawdust. It is regarded as a toxicant and an inhibitor to the growth of microorganism in both sewage disposal and biological fermentation. A furfural-degrading strain (DS1) was isolated from activated sludge of wastewater treatment plant in a diosgenin factory by continuous enrichment culture. The strain was identified as Bacillus cereus based on morphological, physiological tests, as well as on 16S rDNA sequence and Biolog analyses. The capacity of this strain to grow on a mineral salt medium, utilizing furfural as the sole carbon and energy source to degrade furfural, was investigated in this study. Under the condition of pH 9.0, temperature 35 °C, with rotating speed of 150 rpm, and an inoculum of 6 %, the strain showed that the furfural degradation capacity reaches 35 % in 7 days, as measured by high-performance liquid chromatography. The addition of inorganic carbon sources could bring down the biodegradation efficiency of the furfural. The strain DS1 showed better furfural removal capacity, as compared to other inorganic carbon sources in the media. Furthermore, a furfural concentration of as high as 4,000 mg L(-1) was tolerated by the culture. The capacity to degrade furfural was demonstrated for the first time by using the genus B. cereus. This study suggests the possible application in biodegradation strategies.

Silencing the SpMPK1, SpMPK2, and SpMPK3 Genes in Tomato Reduces Abscisic Acid—Mediated Drought Tolerance

Directory of Open Access Journals (Sweden)

Yan Liang

2013-11-01

Full Text Available Drought is a major threat to agriculture production worldwide. Mitogen-activated protein kinases (MAPKs play a pivotal role in sensing and converting stress signals into appropriate responses so that plants can adapt and survive. To examine the function of MAPKs in the drought tolerance of tomato plants, we silenced the SpMPK1, SpMPK2, and SpMPK3 genes in wild-type plants using the virus-induced gene silencing (VIGS method. The results indicate that silencing the individual genes or co-silencing SpMPK1, SpMPK2, and SpMPK3 reduced the drought tolerance of tomato plants by varying degrees. Co-silencing SpMPK1 and SpMPK2 impaired abscisic acid (ABA-induced and hydrogen peroxide (H2O2-induced stomatal closure and enhanced ABA-induced H2O2 production. Similar results were observed when silencing SpMPK3 alone, but not when SpMPK1 and SpMPK2 were individually silenced. These data suggest that the functions of SpMPK1 and SpMPK2 are redundant, and they overlap with that of SpMPK3 in drought stress signaling pathways. In addition, we found that SpMPK3 may regulate H2O2 levels by mediating the expression of CAT1. Hence, SpMPK1, SpMPK2, and SpMPK3 may play crucial roles in enhancing tomato plants’ drought tolerance by influencing stomatal activity and H2O2 production via the ABA-H2O2 pathway.

Biodegradation of dimethyl phthalate, diethyl phthalate and di-n-butyl phthalate by Rhodococcus sp. L4 isolated from activated sludge.

Science.gov (United States)

Lu, Yi; Tang, Fei; Wang, Ying; Zhao, Jinhui; Zeng, Xin; Luo, Qifang; Wang, Lin

2009-09-15

In this study, an aerobic bacterial strain capable of utilizing dimethyl phthalate (DMP), diethyl phthalate (DEP) and di-n-butyl phthalate (DBP) as sole carbon source and energy was isolated from activated sludge collected from a dyeing plant. According to its morphology, physiochemical characteristics and 16S rDNA sequence, the strain was identified as Rhodococcus ruber. The biodegradation batch tests of DMP, DEP and DBP by the Rhodococcus sp. L4 showed the optimal pH value, temperature and substrate concentration: pH 7.0-8.0, 30-37 degrees C and PAEs concentration Kinetics of degradation have also been performed at different initial concentrations. The results show that the degradation can be described with exponential model. The half-life of degradation was about 1.30 days when the concentration of PAEs mixture was lower than 300 mg/L. PAEs contaminated water samples (300 mg/L) with non-emulsification and completed emulsification were prepared to investigate the effect on PAEs degradation rate. Little difference between the above two sample preparations was observed in terms of ultimate degradation rate. Rhodococcus sp. L4 can also grow on phenol, sodium benzoate or naphthalene solution as sole carbon source and energy which suggests its ability in resisting environmental toxicants. This work provides some new evidence for the possibility of applying Rhodococcus for contaminated water remediation in the area of industry.

Purification and properties of a novel quizalofop-p-ethyl-hydrolyzing esterase involved in quizalofop-p-ethyl degradation by Pseudomonas sp. J-2.

Science.gov (United States)

Zhang, Hui; Li, Mengya; Li, Jie; Wang, Guangli; Liu, Yuan

2017-05-10

Quizalofop-p-ethyl (QPE) is a post-emergence herbicide that effectively controls grass weeds and is often detected in the environment. However, the biochemical and molecular mechanisms of QPE degradation in the environment remains unclear. In this study, a highly effective QPE-degrading bacterial strain J-2 was isolated from acclimated activated sludge and identified as a Pseudomonas sp., containing the QPE breakdown metabolite quizalofop acid (QA) identified by Liquid Chromatography-Ion Trap-Mass Spectrometry (LC-IT-MS n ) analysis. A novel QPE hydrolase esterase-encoding gene qpeH was cloned from strain J-2 and functionally expressed in Escherichia coli BL21 (DE3). The specific activity of recombinant QpeH was 198.9 ± 2.7 U mg -1 for QPE with K m and K cat values of 41.3 ± 3.6 μM and 127.3 ± 4.5 s -1 . The optimal pH and temperature for the recombinant QpeH were 8.0 and 30 °C, respectively and the enzyme was activated by Ca 2+ , Cd 2+ , Li + , Fe 3+ and Co 2+ and inhibited by Ni 2+ , Fe 2+ , Ag + , DEPC, SDS, Tween 80, Triton X, β-mercaptoethanol, PMSF, and pCMB. In addition, the catalytic efficiency of QpeH toward different AOPP herbicides in descending order was as follows: fenoxaprop-P-ethyl > quizalofop-P-tefuryl > QPE > haloxyfop-P-methyl > cyhalofopbutyl > clodinafop-propargyl. On the basis of the phylogenetic analysis and multiple sequence alignment, the identified enzyme QpeH, was clustered with esterase family V, suggesting a new member of this family because of its low similarity of amino acid sequence with esterases reported previously.

Ovos de Toxocara sp. e larvas de Ancylostoma sp. em praça pública de Lavras, MG Toxocara sp. eggs and Ancylostoma sp. larva in public parks, Brazil

Directory of Open Access Journals (Sweden)

Antônio Marcos Guimarães

2005-04-01

Full Text Available Larva migrans visceral e cutânea são zoonoses parasitárias causadas pela infecção da larva de Toxocara sp. e Ancylostoma sp., respectivamente. O objetivo do estudo foi verificar a contaminação por ovos de Toxocara sp. e ovos e larvas de Ancylostoma sp. em amostras de solos coletadas de praças públicas e de áreas de recreação infantil de Lavras, Estado de Minas Gerais, por meio da técnica de centrífugo-flutuação e do método de Baermann. A ocorrência de ovos de Toxocara sp. e, ovos e larvas de Ancylostoma sp. foi observada em 69,6% (16/23 das amostras de solo coletadas de praças públicas. A contaminação somente por ovos de Ancylostoma sp. em amostras de solo coletadas em escolas/creches foi de 22,2% (4/18. A percentagem de amostras de areia coletadas de escolas/creches contaminadas somente com larvas de Ancylostoma sp. foi de 11,1% (2/18. Praças públicas são as áreas com maior risco potencial de infecção por Toxocara sp. e Ancylostoma sp. Exame coproparasitológico realizado em 174 amostras de fezes de cães observou 58% e 23%, respectivamente, com ovos de Ancylostoma sp. e Toxocara sp.Visceral and cutaneous larva migrans are parasitic zoonoses caused by the infection of larval nematodes Toxocara sp. and Ancylostoma sp. respectively. The objective of this study was to investigate the contamination by Toxocara sp. eggs and Ancylostoma sp. eggs and larva of soil samples collected from public parks and children's playground areas in state of Minas Gerais, Brazil, using both Baermann's method and centrifugal flotation technique. Toxocara sp. and Ancylostoma sp. eggs were observed in soil samples collected from public squares in 17.4% (4/23 and 69.6 (16/23 respectively. In schools and child day care settings the contamination by Ancylostoma sp. larva in sand samples was 11.1% (2/18. Public parks are settings of more potential risk of Toxocara sp. eggs and Ancylostoma sp. infection. Stool parasitology testing of 174 stool

Field electron emission characteristics of chemical vapour deposition diamond films with controlled sp2 phase concentration

International Nuclear Information System (INIS)

Lu, X.; Yang, Q.; Xiao, C.; Hirose, A.

2008-01-01

Diamond films were synthesized in a microwave plasma-enhanced chemical vapour deposition reactor. The microstructure and surface morphology of deposited films were characterized by Raman spectroscope and scanning electron microscope. The sp 2 phase concentration in diamond films was varied and its effect on the field electron emission (FEE) properties was investigated. Diamond films deposited under higher methane concentration exhibit better FEE property including lower turn-on electric field and larger emission current. The predominating factor modifying the FEE property is presumed to be the increase of sp 2 phase concentration. The influence of bias voltage on the FEE property of diamond films is not monotonic. Postgrowth acid treatment reduces the sp 2 phase content in diamond films without changing diamond grain sizes. The corresponding FEE property was degraded

Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1

International Nuclear Information System (INIS)

Deng, Shuyan; Chen, Yao; Wang, Daosheng; Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong; Hua, Rimao; Tang, Xinyun; Li, Qing X.

2015-01-01

Highlights: • Stenotrophomonas sp. G1 was isolated from chlorpyrifos contaminated sludge. • Strain G1 is closest to Stenotrophomonas acidaminiphila. • Strain G1 can efficiently degrade 8 organophosphorus pesticides (OPs). • Intracellular methyl parathion hydrolase is responsible for the OP degradation. • Three factors were orthogonally optimized for degradation of methyl parathion. - Abstract: Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation

Rapid biodegradation of organophosphorus pesticides by Stenotrophomonas sp. G1

Energy Technology Data Exchange (ETDEWEB)

Deng, Shuyan; Chen, Yao [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Wang, Daosheng [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Shi, Taozhong; Wu, Xiangwei; Ma, Xin; Li, Xiangqiong [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Hua, Rimao, E-mail: rimaohua@ahau.edu.cn [Key Laboratory of Agri-food Safety of Anhui Province, Lab of Quality & Safety and Risk Assessment for Agro-products on Storage and Preservation (Hefei), Ministry of Agriculture, School of Resource and Environment, Anhui Agricultural University, Hefei 230036 (China); Tang, Xinyun [School of Life Science, Anhui Agricultural University, Hefei 230036 (China); Li, Qing X. [Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, 1955 East–West Road, Honolulu, HI 957822 (United States)

2015-10-30

Highlights: • Stenotrophomonas sp. G1 was isolated from chlorpyrifos contaminated sludge. • Strain G1 is closest to Stenotrophomonas acidaminiphila. • Strain G1 can efficiently degrade 8 organophosphorus pesticides (OPs). • Intracellular methyl parathion hydrolase is responsible for the OP degradation. • Three factors were orthogonally optimized for degradation of methyl parathion. - Abstract: Organophosphorus insecticides have been widely used, which are highly poisonous and cause serious concerns over food safety and environmental pollution. A bacterial strain being capable of degrading O,O-dialkyl phosphorothioate and O,O-dialkyl phosphate insecticides, designated as G1, was isolated from sludge collected at the drain outlet of a chlorpyrifos manufacture plant. Physiological and biochemical characteristics and 16S rDNA gene sequence analysis suggested that strain G1 belongs to the genus Stenotrophomonas. At an initial concentration of 50 mg/L, strain G1 degraded 100% of methyl parathion, methyl paraoxon, diazinon, and phoxim, 95% of parathion, 63% of chlorpyrifos, 38% of profenofos, and 34% of triazophos in 24 h. Orthogonal experiments showed that the optimum conditions were an inoculum volume of 20% (v/v), a substrate concentration of 50 mg/L, and an incubation temperature in 40 °C. p-Nitrophenol was detected as the metabolite of methyl parathion, for which intracellular methyl parathion hydrolase was responsible. Strain G1 can efficiently degrade eight organophosphorus pesticides (OPs) and is a very excellent candidate for applications in OP pollution remediation.

Biodegradation of methyl tert-butyl ether by Kocuria sp.

Directory of Open Access Journals (Sweden)

Kiković Dragan D.

2012-01-01

Full Text Available Methyl tert-butyl ether (MTBE has been used to replace the toxic compounds from gasoline and to reduce emission of air pollutants. Due to its intensive use, MTBE has become one of the most important environment pollutants. The aim of this paper is isolation and identification of the bacteria from wastewater sample of “HIP Petrohemija” Pančevo (Serbia, capable of MTBE biodegradation. The results of the investigation showed that only the bacterial isolate 27/1 was capable of growth on MTBE. The result of sequence analyzes of 16S rDNA showed that this bacterial isolate belongs to the Kocuria sp. After the incubation period of 86 days, the degradation rates of initial MTBE concentration of 25 and 125 μg/ml were 55 and 36%, respectively. These results indicated that bacteria Kocuria sp. is successfully adapted on MTBE and can be potentially used in bioremediation of soils and waters contaminated with MTBE.

Expression, Characterization and Synergistic Interactions of Myxobacter Sp. AL-1 Cel9 and Cel48 Glycosyl Hydrolases

Directory of Open Access Journals (Sweden)

Mario Pedraza-Reyes

2008-02-01

Full Text Available The soil microorganism Myxobacter Sp. AL-1 regulates in a differential manner the production of five extracellular cellulases during its life cycle. The nucleotide sequence of a cel9-cel48 cluster from the genome of this microorganism was recently obtained. Cel48 was expressed in Escherichia coli to generate a His6-Cel48 protein and the biochemical properties of the pure protein were determined. Cel48 was more efficient in degrading acid-swollen avicel (ASC than carboxymethylcellulose (CMC. On the other hand, cel9 was expressed in Bacillus subtilis from an IPTG-inducible promoter. Zymogram analysis showed that after IPTG-induction, Cel9 existed in both the cell fraction and the culture medium of B. subtilis and the secreted protein was purified to homogeneity by FPLC-ionic exchange chromatography. The exocellobiohydrolase Cel48 showed a synergism of 1.68 times with the endocellulase Cel9 during ASC degradation using an 8.1- fold excess of Cel48 over Cel9. Western blot analysis revealed that both proteins were synthesized and secreted to the culture medium of Myxobacter Sp. AL-1. These results show that the cel9-cel48 cluster encodes functional endo- and exo-acting cellulases that allows Myobacter Sp. AL-1 to hydrolyse cellulose.

The effect of structure and a secondary carbon source on the microbial degradation of chlorophenoxy acids.

Science.gov (United States)

Evangelista, S; Cooper, D G; Yargeau, V

2010-05-01

Pseudomonas putida, Aspergillus niger, Bacillus subtilis, Pseudomonas fluorescens, Sphingomonas herbicidovorans and Rhodococcus rhodochrous growing on glucose in a medium containing one of three chlorophenoxy acids at a concentration of 0.1 g L(-1) (clofibric acid, (R)-2-(4-chloro-2-methylphenoxy)propionic acid (mecoprop or MCPP) and 4-chloro-2-methylphenoxyacetic acid (MCPA)) degraded these compounds to varying degrees; from nonmeasurable to almost complete removal. These results with the addition of glucose (2.5 g L(-1)) as an easy to use carbon source indicated the formation of metabolites different from results reported in the literature for growth studies in which the chlorophenoxy acid was the sole carbon source. The metabolite, 4-chloro-2-methylphenol, which had been reported previously, was only observed in trace amounts for MCPP and MCPA in the presence of S. herbicidovorans and glucose. In addition, three other compounds (M1, M3 and M4) were observed. It is suggested that these unidentified metabolites resulted from ring opening of the metabolite 4-chloro-2-methylphenol (M2). The rate of biodegradation of the chlorophenoxy acids was influenced by the degree of steric hindrance adjacent to the internal oxygen bond common to all three compounds. The most hindered compound, clofibric acid, was converted to ethyl clofibrate by R. rhodochrous but was not degraded by any microorganisms studied. The more accessible internal oxygen bonds of the other two chlorophenoxy acids, MCPP and MCPA, were readily broken by S. herbicidovorans. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Influence of temperature on nucleus degradation of 4-androstene-3, 17-dione in phytosterol biotransformation by Mycobacterium sp.

Science.gov (United States)

Xu, X W; Gao, X Q; Feng, J X; Wang, X D; Wei, D Z

2015-07-01

One of the steroid intermediates, 4-androstene-3, 17-dione (AD), in the biotransformation of phytosterols is valuable for the production of steroid medicaments. However, its degradation during the conversion process is one of the main obstacles to obtain high yields. In this study, the effect of temperature on nucleus degradation during microbial biotransformation of phytosterol was investigated. The results indicated that microbial degradation of phytosterol followed the AD-ADD-'9-OH-ADD' pathway, and that two important reactions involved in nucleus degradation, conversions of AD to ADD and ADD to 9-OH-ADD, were inhibited at 37°C. With a change in the culture temperature from 30 to 37°C, nucleus degradation was reduced from 39·9% to 17·6%, due to inhibition of the putative KstD and Ksh. These results suggested a simple way to decrease the nucleus degradation in phytosterol biotransformation and a new perspective on the possibilities of modifying the metabolism of strains used in industrial applications. Nucleus degradation of products is one of the main problems encountered during phytosterol biotransformation. To solve this problem, the effect of temperature on nucleus degradation was investigated in the industrial production of steroid intermediates. The results are also helpful to the genetic modification of sterol-producing strains. © 2015 The Society for Applied Microbiology.

Antibacterial Actions and Potential Phototoxic Effects of Volatile oils of Foeniculum sp. (fennel, Salvia sp. (sage, Vitis sp. (grape, Lavandula sp. (lavender

Directory of Open Access Journals (Sweden)

Elif Ayse Erdogan Eliuz

2016-09-01

Full Text Available In the present study, the volatile compounds of essential oil of Foeniculum vulgare (fennel, Salvia officinalis (sage, Vitis vinifera (grape, Lavandula angustifolia (lavender were analysed by gas chromatography-mass spectrometry (GC-MS using the Nist and Willey libraries. It was determined that the main components of Foeniculum sp. were anethole (41.11%, carvacrol (9.18%. whereas main components of Salvia sp were 1.8 cineole (34.09%, caryophyllene (10.95%, camphor (9.44%, α-pinene (8.42%. Vitis sp. contained linoleic acid (36.98%, 2,4-decadienal (30.79%. Finally, volatile component of Lavandula sp. was linalool (33.57%, linalyl acetate (30.74%. Photoxic antibacterial activity of volatile oil of those plants against Escherichia coli (ATCC 25293, Klebsiella pneumoniae (10031, Salmonella thyphimurium, Bacillus subtilis (ATCC 6633, Staphylococcus aureus (ATCC 25925, Enterococcus feacalis (ATCC 29212 were examined by using disc diffusion method. We demonstrated that volatile oil effectively can be activated by a standard LED light. In vitro, significant phototoxicity was demonstrated by volatile oil of Foeniculum sp. and Vitis sp. (P < 0.05, while minor phototoxicity was induced by Lavandula sp. Therefore, volatile oil of plant can be considered as a potential photosensitizer in the photochemical therapy.

Comparative metagenomic analysis of soil microbial communities across three hexachlorocyclohexane contamination levels.

Directory of Open Access Journals (Sweden)

Naseer Sangwan

Full Text Available This paper presents the characterization of the microbial community responsible for the in-situ bioremediation of hexachlorocyclohexane (HCH. Microbial community structure and function was analyzed using 16S rRNA amplicon and shotgun metagenomic sequencing methods for three sets of soil samples. The three samples were collected from a HCH-dumpsite (450 mg HCH/g soil and comprised of a HCH/soil ratio of 0.45, 0.0007, and 0.00003, respectively. Certain bacterial; (Chromohalobacter, Marinimicrobium, Idiomarina, Salinosphaera, Halomonas, Sphingopyxis, Novosphingobium, Sphingomonas and Pseudomonas, archaeal; (Halobacterium, Haloarcula and Halorhabdus and fungal (Fusarium genera were found to be more abundant in the soil sample from the HCH-dumpsite. Consistent with the phylogenetic shift, the dumpsite also exhibited a relatively higher abundance of genes coding for chemotaxis/motility, chloroaromatic and HCH degradation (lin genes. Reassembly of a draft pangenome of Chromohalobacter salaxigenes sp. (∼8X coverage and 3 plasmids (pISP3, pISP4 and pLB1; 13X coverage containing lin genes/clusters also provides an evidence for the horizontal transfer of HCH catabolism genes.

DECOLORIZATION OF AZO DYES AND MINERALIZATION OF PHENANTHRENE BY TRAMETES SP. AS03 ISOLATED FROM INDONESIAN MANGROVE FOREST

Directory of Open Access Journals (Sweden)

Asep Hidayat

2014-04-01

Full Text Available Textile industry contributes the most disposals of synthetic dyes, and about 40% of textile dyes has been generating high amount of colored wastewater. Polycyclic aromatic hydrocarbons (PAHs, such as phenanthrene, is a group of organic compounds, that structurally comprised of two or more benzene rings, which persist in air, water, and soil. The organic pollutants of dyes and PAHs have adversely effects the food chain and are potentially toxic, mutagenic, and carcinogenic to the environment. The objective of this research is to screen and investigate the potential fungus from mangrove forest to degrade azo dyes and phenanthrene.  In this study, fungi were collected from mangrove forest in Riau Province – Sumatra – Indonesia. Previously, Trametes sp. AS03 is one of the fungi isolated from mangrove forest in Riau Province, that was able to decolorize Remazol Brilliant Blue R (RBBR. The capability of Trametes sp. AS03 to decolorize four azo dyes, Remazol B. Violet (V5, Levafix Orange E3GA (Or64, Levafix B. Red E-6BA (R159, and Sumifix S. Scarlet 2GF (R222, were further evaluated. The result shows that Trametes sp. AS03 decolorized 91, 60, 48, and 31 of V5, R222, R159, and Or64, respectively. By showing its capability to decolorize some of the dyes, Trametes sp. AS03 was used to break down phenanthrene. AS03 degraded more than 70% of phenanthrene in 15 days.

Production, Optimization, and Characterization of Organic Solvent Tolerant Cellulases from a Lignocellulosic Waste-Degrading Actinobacterium, Promicromonospora sp. VP111.

Science.gov (United States)

Thomas, Lebin; Ram, Hari; Kumar, Alok; Singh, Ved Pal

2016-07-01

High costs of natural cellulose utilization and cellulase production are an industrial challenge. In view of this, an isolated soil actinobacterium identified as Promicromonospora sp. VP111 showed potential for production of major cellulases (CMCase, FPase, and β-glucosidase) utilizing untreated agricultural lignocellulosic wastes. Extensive disintegration of microcrystalline cellulose and adherence on it during fermentation divulged true cellulolytic efficiency of the strain. Conventional optimization resulted in increased cellulase yield in a cost-effective medium, and the central composite design (CCD) analysis revealed cellulase production to be limited by cellulose and ammonium sulfate. Cellulase activities were enhanced by Co(+2) (1 mM) and retained up to 60 °C and pH 9.0, indicating thermo-alkaline tolerance. Cellulases showed stability in organic solvents (25 % v/v) with log P ow  ≥ 1.24. Untreated wheat straw during submerged fermentation was particularly degraded and yielded about twofold higher levels of cellulases than with commercial cellulose (Na-CMC and avicel) which is especially economical. Thus, this is the first detailed report on cellulases from an efficient strain of Promicromonospora that was non-hemolytic, alkali-halotolerant, antibiotic (erythromycin, kanamycin, rifampicin, cefaclor, ceftazidime) resistant, multiple heavy metal (Mo(+6) = W(+6) > Pb(+2) > Mn(+2) > Cr(+3) > Sn(+2)), and organic solvent (n-hexane, isooctane) tolerant, which is industrially and environmentally valuable.

Physicochemical parameters influencing coaggregation between the freshwater bacteria Sphingomonas natatoria 2.1 and Micrococcus luteus 2.13.

Science.gov (United States)

Min, K R; Zimmer, M N; Rickard, A H

2010-11-01

The aim of this study was to explore the physicochemical parameters that influence coaggregation between the freshwater bacteria Sphingomonas natatoria 2.1 and Micrococcus luteus 2.13. Using visual coaggregation assays, the effect of different buffers, solutions of differing ionic strength, pH, temperature, and viscosity on the degree of coaggregation was assessed. Coaggregation occurred maximally in distilled water but was inhibited when coaggregates were suspended in a commonly-used oral bacterial coaggregation buffer, saline solutions, and Tris-Cl buffers. Coaggregation was weakly expressed in standard laboratory buffers. The ionic strength of inorganic salt solutions required to inhibit coaggregation depended upon the inorganic salt being tested. Coaggregation occurred at a pH of 3-10, between 5 and 80°C and was inhibited in solutions with a viscosity of 22.5 centipoises at 20°C. Inhibition of coaggregation with NaCl impaired biofilm development. When developing buffers to test for coaggregation, the natural liquid environment should be considered. Coaggregation between S. natatoria 2.1 and M. luteus 2.13 is only affected by physicochemical conditions beyond those typically found in natural freshwater ecosystems. Such a robust ability to coaggregate may enhance the ability of S. natatoria 2.1 and M. luteus 2.13 to develop a niche in freshwater biofilms.

Biodegradation of buprofezin by Rhodococcus sp. strain YL-1 isolated from rice field soil.

Science.gov (United States)

Li, Chao; Zhang, Ji; Wu, Zhi-Guo; Cao, Li; Yan, Xin; Li, Shun-Peng

2012-03-14

A buprofezin-degrading bacterium, YL-1, was isolated from rice field soil. YL-1 was identified as Rhodococcus sp. on the basis of the comparative analysis of 16S rDNA sequences. The strain could use buprofezin as the sole source of carbon and nitrogen for growth and was able to degrade 92.4% of 50 mg L(-1) buprofezin within 48 h in liquid culture. During the degradation of buprofezin, four possible metabolites, 2-tert-butylimino-3-isopropyl-1,3,5-thiadiazinan-4-one, N-tert-butyl-thioformimidic acid formylaminomethyl ester, 2-isothiocyanato-2-methyl-propane, and 2-isothiocyanato-propane, were identified using gas chromatography-mass spectrometry (GC-MS) analysis. The catechol 2,3-dioxygenase activity was strongly induced during the degradation of buprofezin. A novel microbial biodegradation pathway for buprofezin was proposed on the basis of these metabolites. The inoculation of soils treated with buprofezin with strain YL-1 resulted in a higher degradation rate than that observed in noninoculated soils, indicating that strain YL-1 has the potential to be used in the bioremediation of buprofezin-contaminated environments.

Biodegradation of cyanide by acetonitrile-induced cells of Rhodococcus sp. UKMP-5M.

Science.gov (United States)

Nallapan Maniyam, Maegala; Sjahrir, Fridelina; Ibrahim, Abdul Latif; Cass, Anthony E G

2013-01-01

A Rhodococcus sp. UKMP-5M isolate was shown to detoxify cyanide successfully, suggesting the presence of an intrinsic property in the bacterium which required no prior cyanide exposure for induction of this property. However, in order to promote growth, Rhodococcus sp. UKMP-5M was fully acclimatized to cyanide after 7 successive subcultures in 0.1 mM KCN for 30 days. To further shorten the lag phase and simultaneously increase the tolerance towards higher cyanide concentrations, the bacterium was induced with various nitrile compounds sharing a similar degradatory pathway to cyanide. Acetonitrile emerged as the most favored inducer and the induced cells were able to degrade 0.1 mM KCN almost completely within 18 h. With the addition of subsequent aliquots of 0.1 mM KCN a shorter period for complete removal of cyanide was required, which proved to be advantageous economically. Both resting cells and crude enzyme of Rhodococcus sp. UKMP-5M were able to biodegrade cyanide to ammonia and formate without the formation of formamide, implying the identification of a simple hydrolytic cyanide degradation pathway involving the enzyme cyanidase. Further verification with SDS-PAGE revealed that the molecular weight of the active enzyme was estimated to be 38 kDa, which is consistent with previously reported cyanidases. Since the recent advancement in the application of biological methods in treating cyanide-bearing wastewater has been promising, the discovery of this new bacterium will add value by diversifying the existing microbial populations capable of cyanide detoxification.

Co-metabolic formation of substituted phenylacetic acids by styrene-degrading bacteria

Directory of Open Access Journals (Sweden)

Michel Oelschlägel

2015-06-01

The styrene-degrading strains Rhodococcus opacus 1CP, Pseudomonas fluorescens ST, and the novel isolates Sphingopyxis sp. Kp5.2 and Gordonia sp. CWB2 were investigated with respect to their applicability to co-metabolically produce substituted phenylacetic acids. Isolates were found to differ significantly in substrate tolerance and biotransformation yields. Especially, P. fluorescens ST was identified as a promising candidate for the production of several phenylacetic acids. The biotransformation of 4-chlorostyrene with cells of strain ST was shown to be stable over a period of more than 200 days and yielded about 38 mmolproduct gcelldryweight−1 after nearly 350 days. Moreover, 4-chloro-α-methylstyrene was predominantly converted to the (S-enantiomer of the acid with 40% enantiomeric excess.

Enterocin T, a novel class IIa bacteriocin produced by Enterococcus sp. 812.

Science.gov (United States)

Chen, Yi-Sheng; Yu, Chi-Rong; Ji, Si-Hua; Liou, Min-Shiuan; Leong, Kun-Hon; Pan, Shwu-Fen; Wu, Hui-Chung; Lin, Yu-Hsuan; Yu, Bi; Yanagida, Fujitoshi

2013-09-01

Enterococcus sp. 812, isolated from fresh broccoli, was previously found to produce a bacteriocin active against a number of Gram-positive bacteria, including Listeria monocytogenes. Bacteriocin activity decreased slightly after autoclaving (121 °C for 15 min), but was inactivated by protease K. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 4,521.34 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2-ATYYGNGVYXDKKKXWVEWGQA, by Edman degradation, which contained the consensus class IIa bacteriocin motif YGNGV in the N-terminal region. The obtained partial sequence showed high homology with some enterococcal bacteriocins; however, no identical peptide or protein was found. This peptide was therefore considered to be a novel bacteriocin produced by Enterococcus sp. 812 and was termed enterocin T.

Cloning, expression, purification, crystallization and preliminary crystallographic studies of UgdG, an UDP-glucose dehydrogenase from Sphingomonas elodea ATCC 31461

International Nuclear Information System (INIS)

Rocha, Joana; Granja, Ana Teresa; Sá-Correia, Isabel; Fialho, Arsénio; Frazão, Carlos

2009-01-01

Crystals of S. elodea ATCC 31461 UDP-glucose dehydrogenase (EC 1.1.1.22) were obtained in space groups P622 and P4 3 2 1 2 and diffracted to 2.4 and 3.4 Å resolution, respectively. Gellan gum, a commercial gelling agent produced by Sphingomonas elodea ATCC 31461, is a high-value microbial exopolysaccharide. UDP-glucose dehydrogenase (UGD; EC 1.1.1.22) is responsible for the NAD-dependent twofold oxidation of UDP-glucose to UDP-glucuronic acid, one of the key components for gellan biosynthesis. S. elodea ATCC 31461 UGD, termed UgdG, was cloned, expressed, purified and crystallized in native and SeMet-derivatized forms in hexagonal and tetragonal space groups, respectively; the crystals diffracted X-rays to 2.40 and 3.40 Å resolution, respectively. Experimental phases were obtained for the tetragonal SeMet-derivatized crystal form by a single-wavelength anomalous dispersion experiment. This structure was successfully used as a molecular-replacement probe for the hexagonal crystal form of the native protein

Bradysia sp. em morangueiro Bradysia sp. in strawberry

Directory of Open Access Journals (Sweden)

Bernadete Radin

2009-04-01

Full Text Available No trabalho, relatam-se os primeiros registros de Bradysia sp. (Insecta: Diptera: Sciaridae em morangueiro (Fragaria x ananassa Duch., cultivado no Município de Eldorado do Sul, RS. O cultivo foi realizado em sacolas com três metros de comprimento, preenchidas com substrato composto de casca de arroz e turfa, dispostas horizontalmente sobre bancadas de madeira, em ambiente protegido. A presença de Bradysia sp. foi observada na segunda quinzena de agosto de 2005. Neste trabalho, estão descritos os sintomas apresentados no morangueiro pela praga, prováveis conseqüências sobre o aparecimento de doenças e uma breve descrição morfológica da Bradysia sp., adulto e fase larval.This paper describes the first record of Bradysia sp. (Insecta; Diptera; Sciaridae in strawberry (Fragaria x ananassa, cultivated in the city of Eldorado do Sul, RS, Brazil. Strawberry was planted in plastic bags filled with a mixture of burnt rice hulls and peat and cultivated in a greenhouse. The presence of Bradysia sp was noticed in the second fortnight of August, 2005. The symptoms in strawberry and the probable consequences in terms of disease arising were described in the present study, as well as the morphological characterization of Bradysia sp. and its illustrations.

Benzo[4,5]cyclohepta[1,2-b]fluorene: an isomeric motif for pentacene containing linearly fused five-, six- and seven-membered rings

KAUST Repository

Yang, Xuejin

2016-06-07

Benzo[4,5]cyclohepta[1,2-b]fluorene (5a), a new π-conjugated polycyclic hydrocarbon containing linearly fused six-, five-, six-, seven- and six-membered rings (C6-C5-C6-C7-C6), was designed and its stable derivatives 5b and 5c were synthesized. With 22 π electrons, 5a is an isomer of pentacene with quinoidal, dipolar ionic and diradical resonance forms. Molecules 5b and 5c were experimentally investigated with cyclic voltammetry, electronic absorption spectroscopy and X-ray crystallographic analysis, and theoretically studied by calculating the NICS value, diradical character and dipole moment. A comparison of 5a–c with pentacene and other pentacene analogues containing linearly fused five- or seven- membered rings was also conducted and discussed. It was found that 5b behaved as a p-type organic semiconductor in solution-processed thin film transistors with field effect mobility of up to 0.025 cm2/Vs.

Benzo[4,5]cyclohepta[1,2-b]fluorene: an isomeric motif for pentacene containing linearly fused five-, six- and seven-membered rings

KAUST Repository

Yang, Xuejin; Shi, Xueliang; Aratani, Naoki; Goncalves, Theo; Huang, Kuo-Wei; Yamada, Hiroko; Chi, Chunyan; Miao, Qian

2016-01-01

Benzo[4,5]cyclohepta[1,2-b]fluorene (5a), a new π-conjugated polycyclic hydrocarbon containing linearly fused six-, five-, six-, seven- and six-membered rings (C6-C5-C6-C7-C6), was designed and its stable derivatives 5b and 5c were synthesized. With 22 π electrons, 5a is an isomer of pentacene with quinoidal, dipolar ionic and diradical resonance forms. Molecules 5b and 5c were experimentally investigated with cyclic voltammetry, electronic absorption spectroscopy and X-ray crystallographic analysis, and theoretically studied by calculating the NICS value, diradical character and dipole moment. A comparison of 5a–c with pentacene and other pentacene analogues containing linearly fused five- or seven- membered rings was also conducted and discussed. It was found that 5b behaved as a p-type organic semiconductor in solution-processed thin film transistors with field effect mobility of up to 0.025 cm2/Vs.

Delignification and Enhanced Gas Release from Soil Containing Lignocellulose by Treatment with Bacterial Lignin Degraders.

Science.gov (United States)

Rashid, Goran M M; Duran-Pena, Maria Jesus; Rahmanpour, Rahman; Sapsford, Devin; Bugg, Timothy D H

2017-04-10

The aim of the study was to isolate bacterial lignin-degrading bacteria from municipal solid waste soil, and to investigate whether they could be used to delignify lignocellulose-containing soil, and enhance methane release. A set of 20 bacterial lignin degraders, including 11 new isolates from municipal solid waste soil, were tested for delignification and phenol release in soil containing 1% pine lignocellulose. A group of 7 strains were then tested for enhancement of gas release from soil containing 1% lignocellulose in small-scale column tests. Using an aerobic pre-treatment, aerobic strains such as Pseudomonas putida showed enhanced gas release from the treated sample, but four bacterial isolates showed 5-10 fold enhancement in gas release in an in situ experiment under microanaerobic conditions: Agrobacterium sp., Lysinibacillus sphaericus, Comamonas testosteroni, and Enterobacter sp.. The results show that facultative anaerobic bacterial lignin degraders found in landfill soil can be used for in situ delignification and enhanced gas release in soil containing lignocellulose. The study demonstrates the feasibility of using an in situ bacterial treatment to enhance gas release and resource recovery from landfill soil containing lignocellulosic waste. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Kinetics of pyridine degradation along with toluene and methylene chloride with Bacillus sp. in packed bed reactor

Energy Technology Data Exchange (ETDEWEB)

Uma, B.; Sandhya, S. [National Environmental Engineering Research Institute, CSIR-Complex, Madras (India)

1998-04-01

Bacillus coagulans strain isolated from contaminated soil was immobilised on activated carbon for degradation of pyridine, toluene and methylene chloride containing synthetic wastewaters. Pyridine was supplied as the only source of nitrogen in the wastewaters. Continuous runs in a packed bed laboratory reactor showed that immobilized B. coagulans can degrade pyridine along with other organics rapidly and the effluent ammonia is also controlled in presence of ``organic carbon``. About 644 mg/l of influent TOC was efficiently degraded (82.85%) at 64.05 mg/l/hr loading. (orig.) With 2 figs., 4 tabs., 15 refs.

Biodegradation of pentachloronitrobenzene by Cupriavidus sp. YNS-85 and its potential for remediation of contaminated soils.

Science.gov (United States)

Teng, Ying; Wang, Xiaomi; Zhu, Ye; Chen, Wei; Christie, Peter; Li, Zhengao; Luo, Yongming

2017-04-01

Pentachloronitrobenzene (PCNB) is a toxic chlorinated nitroaromatic compound. However, only a few bacteria have been reported to be able to utilize PCNB. In the present study, one pentachloronitrobenzene (PCNB)-degrading bacterium, Cupriavidus sp. YNS-85, was isolated from a contaminated Panax notoginseng plantation. The strain co-metabolized 200 mg L -1 PCNB in aqueous solution with a removal rate of 73.8% after 5 days. The bacterium also degraded PCNB effectively under acid conditions (pH 4-6) and showed resistance to toxic trace elements (arsenic, copper, and cadmium). Its ability to utilize proposed PCNB intermediates as sole carbon sources was also confirmed. The soil microcosm experiment further demonstrated that bacterial bioaugmentation enhanced the removal of PCNB (37.8%) from soil and the accumulation of pentachloroaniline (89.3%) after 30 days. Soil enzyme activity and microbial community functional diversity were positively influenced after bioremediation. These findings indicate that Cupriavidus sp. YNS-85 may be a suitable inoculant for in situ bioremediation of PCNB-polluted sites, especially those with acid soils co-contaminated with heavy metal(loid)s.

INTERAKSI ANTARA Trichoderma Harzianum, Penicillium SP. DAN Pseudomonas SP. SERTA KAPASITAS ANTAGONISMENYA TERHADAP Phytophthora CapsicilN VITRO*[Interaction Among Trichoderma Harzianum, Penicillium SP., Pseudomonas SP. and Antagonism Capacities Against Phy

OpenAIRE

Suharna, Nandang

2003-01-01

A preliminary study has been done to know antagonism capacities of three isolates of Trichoderma harzianum, two isolates of Penicillium sp.and one isolate of Pseudomonas sp.against Phytophthora capsici in vitro and interaction among those six antagonists.The highest antagonism capacity possessed by Penicillium sp. KN1, respectively followed by Penicillium sp.KN2,Pseudomonas sp. GH1 and the three T. harzianum isolates. Except for those three T. harzianum isolates, the two Penicillium sp.isolat...