Biotransformation of 2,4,6-trinitrotoluene (TNT) by a Methanococcus sp. (strain B) isolated from a lake sediment

1994 ◽  
Vol 40 (4) ◽  
pp. 273-278 ◽  
Author(s):  
R. Boopathy ◽  
C. f. Kulpa
Keyword(s):  
Carbon Dioxide ◽  
Mineral Salt Medium ◽  
Optimal Growth ◽  
Sole Source ◽  
Growth Conditions ◽  
Salt Medium ◽  
Ph Range ◽  
The University ◽  
Optimal Ph ◽  
In Cells

A mesophilic, irregular coccoid methanogen, which shows close resemblance to Methanococcus sp., was isolated from a sediment sample of St. Joseph Lake located in the University of Notre Dame campus. Formate or hydrogen plus carbon dioxide served as substrate for methanogenesis in a mineral salt medium. This organism was studied for its ability to metabolize 2,4,6-trinitrotoluene (TNT). The result showed that this isolate could transform 100 ppm of TNT within 40–60 days of incubation at 30 °C. The main intermediate produced was 2,4-diamino-6-nitrotoluene. The TNT transformation rates were higher in cells grown in hydrogen plus carbon dioxide than in cells grown in formate. The isolate did not use acetate and methanol as sole source of carbon and energy. The organism had an optimal pH range of 6.8–7.2. The optimal growth conditions for this isolate are described.Key words: biotransformation, methanogens, bioremediation, nitroaromatics, TNT, anaerobic process.

Monochloroacetate dehalogenase activities of bacterial strains isolated from soil

1995 ◽  
Vol 41 (8) ◽  
pp. 730-739 ◽  
Author(s):  
Amalia Diez ◽  
Maria J. Alvarez ◽  
M. Isabel Prieto ◽  
José M. Bautista ◽  
Amando Garrido-Pertierra
Keyword(s):  
Sole Source ◽  
Growth Conditions ◽  
Atmospheric Nitrogen ◽  
Bacterial Strains ◽  
Ph Profile ◽  
Halogenated Organic Compounds ◽  
High Affinity ◽  
Wide Range ◽  
Ph Range ◽  
Optimal Ph

Seven bacterial strains capable of utilizing monochloroacetate (MCA) at a concentration of 50 mM as the sole carbon source were isolated from soil and displayed MCA dehalogenase activity. Three of them were identified as Pseudomonas spp., and the remaining four strains as Alcaligenes sp., Agrobacterium sp., Arthrobacter sp., and Azotobacter sp. This latter is the first reported example of a bacterium fixing atmospheric nitrogen under aerobic conditions that also uses a chloro-organic compound as sole source of carbon and energy. MCA dehalogenase activity in these strains was found to be inducible under different growth conditions. Crude extracts from all seven isolated strains also displayed dehalogenating activity with a relatively wide range of halogenated organic compounds (aliphatic acids, ketones, alcohols, alkanes, and aromatics), which, depending on the strain, were dehalogenated to different extents. The estimated Km values for MCA were used to classify the dehalogenase activities into three groups: high affinity (30–40 μM) in Alcaligenes and Agrobacterium species, medium affinity (100–180 μM) in Pseudomonas and Azotobacter species, and low affinity (100 mM) in Arthrobacter sp. Both the optimal pH range for MCA dehalogenase activity (between pH 8 and 10) and the pH profile of stability (in the neutral–basic range) were found to be similar in all strains, whereas the thermal stability profiles were variable.Key words: dehalogenase, halohydrolase, monochloroacetate, soil.

Metabolism of a monoterpene alcohol, linalool, by a soil pseudomonad

1977 ◽  
Vol 23 (3) ◽  
pp. 230-239 ◽  
Author(s):  
K. M. Madyastha ◽  
P. K. Bhattacharyya ◽  
C. S. Vaidyanathan
Keyword(s):  
Mineral Salt Medium ◽  
Enrichment Culture ◽  
Sole Source ◽  
Mineral Salt ◽  
Salt Medium ◽  
Culture Techniques ◽  
Unsaturated Lactone ◽  
Linalool Oxide

A microorganism of the genus Pseudomonas has been isolated from the soil by enrichment culture techniques with linalool(I) as the sole source of carbon and energy. The organism is also capable of utilizing limonene, citronellol, and geraniol as substrates but fails to grow on citral, citranellal, and 1,8-cineole. Fermentation of linalool by this bacterium in a mineral salt medium results in the formation of 10-hydroxylinalool(II), 10-carboxylinalool(III), oleuropeic acid(IX), 2-vinyl-2-methyl-5-hydroxyisopropyl-tetrahydrofuran(linalool oxide, V), 2-vinyl-2-methyl-tetrahydrofuran-5-one(unsaturated lactone, VI), and few unidentified minor metabolites. Probable pathways for the biodegradation of linalool are presented.

scholarly journals Removal of tannin from Shea nut cake by Pseudomonas strain

1970 ◽  
Vol 5 (1) ◽  
pp. 17-22
Author(s):  
F.M. Danikuu ◽  
A. Quainoo ◽  
E.N.K. Sowley
Keyword(s):  
Mineral Salt Medium ◽  
Cost Effective ◽  
Sole Source ◽  
Northern Region ◽  
Mineral Salt ◽  
Salt Medium ◽  
Biomedical Sciences ◽  
Nutritional Factors ◽  
Tannin Concentration ◽  
Enhanced Biodegradation

The use of microorganisms to remove the anti-nutritional factors in shea nut cake as the most cost effective and environmentally friendly approach to permit its use in agriculture for animal nutrition and soil fertility is long anticipated. Bacteria isolated from shea nut cake polluted soil in Sagnarigu District of Northern Region of Ghana showed that anti-nutritional factors in shea nut cake are bio-degradable. The bacteria were grown in mineral salt medium supplemented with 2% shea nut cake as sole source of carbon. The bacteria isolate was identified biochemically as Pseudomonas aerugenosa and reduced total tannin concentration in shea nut cake from 54.58 g Kg-1 to 8.71 g Kg-1 (84%) in 10 days and 92% in 20 days. Boiling of shea nut cake reduced tannin content from 54.58 g Kg-1 to 16.36 g Kg-1 (70%) and enhanced biodegradation of tannin in the shea nut cake, removing up to 95% of total tannins in shea nut cake in 20 days.Journal of Medical and Biomedical Sciences (2016) 5(1), 17-22Keywords: Tannins, biodegradability, bacteria, mineral salt medium

Growth characteristics of a cell line derived from the pig oviduct

1975 ◽  
Vol 21 (12) ◽  
pp. 2094-2097 ◽  
Author(s):  
A. M. P. Bouillant ◽  
P. Genest ◽  
A. S. Greig
Keyword(s):  
Cell Line ◽  
Optimal Growth ◽  
Growth Conditions ◽  
Growth Characteristics ◽  
Population Doubling ◽  
Population Doubling Time ◽  
Temperature Growth ◽  
A Cell ◽  
Maximum Population Density ◽  
Optimal Ph

Further evidence for the establishment of the pig fallopian tube (PFT) cell line as a continuous cell line was shown by an increase in the maximum population density as the number of subcultures increased. The optimal pH and temperature–growth ranges appeared to be 7.4–7.8 and 37–41 °C respectively, and the population doubling time was 20–25 h under optimal growth conditions. With progressive subculture, the serum requirements dropped from 20 to 2%. A plating efficiency of 2 to 4% was found in all serial subcultures. Colonies were observed in agar suspension culture at the 146th subculture and thereafter. Chromosomal alterations were found in the 100th subculture and thereafter.

Efficient biodegradation of naphthalene by a newly characterized indigenous Achromobacter sp. FBHYA2 isolated from Tehran Oil Refinery Complex

2012 ◽  
Vol 66 (3) ◽  
pp. 594-602 ◽  
Author(s):  
Sima Farjadfard ◽  
Seyyed Mehdi Borghei ◽  
Amir Hessam Hassani ◽  
Bagher Yakhchali ◽  
Mehdi Ardjmand ◽  
...  
Keyword(s):  
Aromatic Hydrocarbons ◽  
Optimal Growth ◽  
Sole Source ◽  
Growth Conditions ◽  
American Petroleum Institute ◽  
Oil Refinery ◽  
Rrna Gene ◽  
Significant Difference ◽  
Aliphatic And Aromatic Hydrocarbons ◽  
Achromobacter Sp

A bacterial strain, FBHYA2, capable of degrading naphthalene, was isolated from the American Petroleum Institute (API) separator of the Tehran Oil Refinery Complex (TORC). Strain FBHYA2 was identified as Achromobacter sp. based on physiological and biochemical characteristics and also phylogenetic similarity of 16S rRNA gene sequence. The optimal growth conditions for strain FBHYA2 were pH 6.0, 30 °C and 1.0% NaCl. Strain FBHYA2 can utilize naphthalene as the sole source of carbon and energy and was able to degrade naphthalene aerobically very fast, 48 h for 96% removal at 500 mg/L concentration. The physiological response of Achromobacter sp., FBHYA2 to several hydrophobic chemicals (aliphatic and aromatic hydrocarbons) was also investigated. No biosurfactant was detected during bacterial growth on any aliphatic/aromatic hydrocarbons. The results of hydrophobicity measurements showed no significant difference between naphthalene- and LB-grown cells. The capability of the strain FBHYA2 to degrade naphthalene completely and rapidly without the need to secrete biosurfactant may make it an ideal candidate to remediate polycyclic aromatic hydrocarbon (PAH)-contaminated sites.

scholarly journals Estimation of the Yield Coefficient ofPseudomonas sp. Strain DP-4 with a Low Substrate (2,4-Dichlorophenol [DCP]) Concentration in a Mineral Medium from Which Uncharacterized Organic Compounds Were Eliminated by a Non-DCP-Degrading Organism

2000 ◽  
Vol 66 (2) ◽  
pp. 566-570 ◽  
Author(s):  
Mitsunori Tarao ◽  
Masayuki Seto
Keyword(s):  
Mixed Culture ◽  
Organic Compounds ◽  
Pure Culture ◽  
Mineral Salt Medium ◽  
Sole Source ◽  
Final Concentration ◽  
Yield Coefficient ◽  
Salt Medium ◽  
Initial Concentration ◽  
Low Concentrations

ABSTRACT The yield coefficient (YC) of Pseudomonas sp. strain DP-4, a 2,4-dichlorophenol (DCP)-degrading organism, was estimated from the number of CFU produced at the expense of 1 unit amount of DCP at low concentrations. At a low concentration of DCP, the YC can be overestimated in pure culture, because DP-4 assimilated not only DCP but also uncharacterized organic compounds contaminating a mineral salt medium. The concentration of these uncharacterized organic compounds was nutritionally equivalent to 0.7 μg of DCP-C ml−1. A mixed culture with non-DCP-degrading organisms resulted in elimination of ca. 99.9% of the uncharacterized organic compounds, and then DP-4 assimilated only DCP as a substrate. In a mixed culture, DP-4 degraded an initial concentration of 0.1 to 10 μg of C ml of DCP−1 and the number of CFU of DP-4 increased. In the mixed culture, DCP at an initial concentration of 0.07 μg of C ml−1 was degraded. However, the number of CFU of DP-4 did not increase. DCP at an extremely low initial concentration of 0.01 μg of C ml−1 was not degraded in mixed culture even by a high density, 105 CFU ml−1, of DP-4. When glucose was added to this mixed culture to a final concentration of 1 μg of C ml−1, the initial concentration of 0.01 μg of C ml of DCP−1 was degraded. These results suggested that DP-4 required cosubstrates to degrade DCP at an extremely low initial concentration of 0.01 μg of C ml−1. The YCs of DP-4 at the expense of DCP alone decreased discontinuously with the decrease of the initial concentration of DCP, i.e., 1.5, 0.19, or 0 CFU per pg of DCP-C when 0.7 to 10, 0.1 to 0.5, or 0.07 μg of C ml of DCP−1 was degraded, respectively. In this study, we developed a new method to eliminate uncharacterized organic compounds, and we estimated the YC of DP-4 at the expense of DCP as a sole source of carbon.

scholarly journals Treatment of succinonitrile wastewater by immobilized high efficiency microorganism strains

2008 ◽  
Vol 58 (4) ◽  
pp. 911-918 ◽  
Author(s):  
X. F. Zhou ◽  
Y. L. Zhang ◽  
D. Q. Xu ◽  
W. H. Cao ◽  
C. M. Dai ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Sodium Alginate ◽  
High Efficiency ◽  
Treatment Plant ◽  
Optimal Growth ◽  
Sole Source ◽  
Growth Conditions ◽  
Experimental Conditions ◽  
J 13 ◽  
Rotary Speed

Using succinonitrile as a sole source of carbon and nitrogen, two bacterium strains named as J-1-3 and J-13-1 were isolated and screened out from the treatment facilities of Shanghai petrochemical wastewater treatment plant treating acrylic fiber production wastewater. The optimal growth conditions of the two strains in the degradation of succinonitrile with varied initial concentrations were determined through flask tests as follows: temperature 30°C, shaker rotary speed of 250 r/min, inoculum percentage 0.1%, and initial pH 6. Results indicate that the two strains, especially J-13-1, exhibited a high efficiency for succinonitrile degradation. Thereafter, the bacterium strains were immobilized separately by sodium alginate and polyvinyl alcohol 1750±50, and applied to succinonitrile degradation again. Results show that in a very broad range of the initial succinonitrile concentration, i.e., 30–5,000 mg/L, the sodium alginate immobilized grains could degrade more than 80% of succinonitrile after 24 h under the experimental conditions of 30°C, pH 6.5, and shaker rotary speed of 250 r/min. However, the polyvinyl alcohol immobilized grains tended to inflate and break down due to a weak mechanical strength.

scholarly journals Characteristics of Phomopsis juglandina (Sacc.) Hohn. Associated with Dieback of Walnut in the Climatic Conditions of Southern Romania

Agronomy ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 46
Author(s):  
Cristina Mihaescu ◽  
Daniel Dunea ◽  
Adrian Gheorghe Bășa ◽  
Loredana Neagu Frasin
Keyword(s):  
Growth Temperature ◽  
Potential Evapotranspiration ◽  
Optimal Growth ◽  
Climatic Conditions ◽  
Cultural Characteristics ◽  
Optimal Growth Temperature ◽  
Conidial State ◽  
Optimal Ph

Phomopsis juglandina (Sacc.) Höhn., which is the conidial state of Diaporthe juglandina (Fuckel) Nitschke, and the main pathogen causing the dieback of branches and twigs of walnut was recently detected in many orchards from Romania. The symptomatological, morphological, ultrastructural, and cultural characteristics, as well as the pathogenicity of an isolate of this lignicolous fungus, were described and illustrated. The optimum periods for infection, under the conditions prevailing in Southern Romania, mainly occur in the spring (April) and autumn months (late September-beginning of October). Strong inverse correlations (p < 0.001) were found between potential evapotranspiration and lesion lengths on walnut branches in 2019. The pathogen forms two types of phialospores: alpha and beta; the role of beta phialospores is not well known in pathogenesis. In Vitro, the optimal growth temperature of mycelial hyphae was in the range of 22–26 °C, and the optimal pH is 4.4–7. This pathogen should be monitored continuously due to its potential for damaging infestations of intensive plantations.

scholarly journals Isolation of a gene required for programmed initiation of development by Aspergillus nidulans.

1992 ◽  
Vol 12 (9) ◽  
pp. 3827-3833 ◽  
Author(s):  
T H Adams ◽  
W A Hide ◽  
L N Yager ◽  
B N Lee
Keyword(s):  
Life Cycle ◽  
Aspergillus Nidulans ◽  
Optimal Growth ◽  
Growth Conditions ◽  
Nutrient Deprivation ◽  
Deletion Mutants ◽  
Wild Type ◽  
Microbial Development ◽  
Type Strains ◽  
Posttranscriptional Level

In contrast to many other cases in microbial development, Aspergillus nidulans conidiophore production initiates primarily as a programmed part of the life cycle rather than as a response to nutrient deprivation. Mutations in the acoD locus result in "fluffy" colonies that appear to grow faster than the wild type and proliferate as undifferentiated masses of vegetative cells. We show that unlike wild-type strains, acoD deletion mutants are unable to make conidiophores under optimal growth conditions but can be induced to conidiate when growth is nutritionally limited. The requirement for acoD in conidiophore development occurs prior to activation of brlA, a primary regulator of development. The acoD transcript is present both in vegetative hyphae prior to developmental induction and in developing cultures. However, the effects of acoD mutations are detectable only after developmental induction. We propose that acoD activity is primarily controlled at the posttranscriptional level and that it is required to direct developmentally specific changes that bring about growth inhibition and activation of brlA expression to result in conidiophore development.

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