Isolation and characterization of highly thermophilic xylanolyticThermus thermophilusstrains from hot composts

2000 ◽  
Vol 46 (11) ◽  
pp. 1029-1035 ◽  
Author(s):  
Pierre-François Lyon ◽  
Trello Beffa ◽  
Michel Blanc ◽  
Georg Auling ◽  
Michel Aragno
Keyword(s):  
Growth Rate ◽  
Culture Medium ◽  
Xylanase Activity ◽  
Thermostable Enzyme ◽  
Aerobic Bacteria ◽  
Maximal Growth ◽  
Detailed Report ◽  
Xylanolytic Activity ◽  
Isolation And Characterization

This is the first detailed report of xylanolytic activity in Thermus strains. Two highly thermophilic xylanolytic bacteria, very closely related to non-xylanolytic T. thermophilus strains, have been isolated from the hottest zones of compost piles. Strain X6 was investigated in more detail. The growth rate (optical density monitoring) on xylan was 0.404·h-1at 75°C. Maximal growth temperature was 81°C. Xylanase activity was mainly cell-bound, but was solubilized into the medium by sonication. It was induced by xylan or xylose in the culture medium. The temperature and pH optima of the xylanases were determined to be around 100°C and pH 6, respectively. Xylanase activity was fairly thermostable; only 39% of activity was lost after an incubation period of 48 h at 90°C in the absence of substrate. Xylanolytic T. thermophilus strains could contribute to the degradation of hemicellulose during the thermogenic phase of industrial composting.Key words: Thermus, thermophilic aerobic bacteria, xylanase, thermostable enzyme, compost.

Isolation and characterization of the ethynylestradiol-biodegrading microorganism Fusarium proliferatum strain HNS-1

2002 ◽  
Vol 45 (12) ◽  
pp. 175-179 ◽  
Author(s):  
J.H. Shi ◽  
Y. Suzuki ◽  
B.-D. Lee ◽  
S. Nakai ◽  
M. Hosomi
Keyword(s):  
Culture Medium ◽  
Polar Compounds ◽  
Sole Source ◽  
Order Rate Constant ◽  
Fusarium Proliferatum ◽  
Rrna Gene ◽  
28S Rrna ◽  
Isolation And Characterization ◽  
Phenolic Group

We cultivated hundreds of sediment, soil, and manure samples taken from rivers and farms in a medium containing ethynylestradiol (EE2) as the sole source of carbon, so that microorganisms in the samples would acclimatize to the presence of EE2. Finally, we isolated an EE2-degrading microorganism, designated as strain HNS-1, from a cowshed sample. Based on its partial nucleotide sequence (563 bp) of the 28S rRNA gene, strain HNS-1 was identified as Fusarium proliferatum. Over 15 days, F. proliferatum strain HNS-1 removed 97% of EE2 at an initial concentration of 25 mg.L−1, with a first-order rate constant of 0.6 d−1. Unknown products of EE2 degradation, which may be more polar compounds that have a phenolic group, remained in the culture medium.

scholarly journals The formation of Hfr strains inEscherichia coliK12

1967 ◽  
Vol 9 (1) ◽  
pp. 35-47 ◽  
Author(s):  
Paul Broda
Keyword(s):  
Growth Rate ◽  
Bacterial Chromosome ◽  
Nutritional Requirements ◽  
Isolation And Characterization

The isolation and characterization of an isogenic series of twelve Hfr strains is described. From their points of origin it was concluded that the sex factor integrates at a limited number of sites on the bacterial chromosome. Although the nutritional requirements of these Hfr strains were similar to those of the parent F+strain, it was observed that one group had a markedly slower growth rate. The relevance of these observations to theories on the nature of F+fertility and on the formation of Hfr strains is discussed.

Isolation and characterization of bacterial diversity from soils supplemented with electrical transformer fluids

2011 ◽  
Vol 1 (2) ◽  
pp. 107-113
Author(s):  
Nwinyi Obinna C ◽  
Alade Adetutu ◽  
Leo‐ Akpan Imaobong R ◽  
Oladele Bolaji.O
Keyword(s):  
Optical Density ◽  
Culture Medium ◽  
Agricultural Land ◽  
Agricultural Soils ◽  
Bacterial Species ◽  
Minimal Salt Medium ◽  
Isolation And Characterization ◽  
The Mean ◽  
Biomass Increase

Repetitive enrichment of soils samples from an agricultural land and newly marked dumpsite on electrical transformer fluid yielded six bacterial species that have the capacity to utilize electrical transformer fluids (askarel) as carbon and energy source. Bacterial species namely: Micrococcus, Arthrobacter, Pseudomonas putida, Pseudomonas spp, Norcadia and Corynebacterium were identified using morphological and biochemical characteristics. The abilities of these bacterial species to utilize the electrical transformer fluids as carbon source in minimal salt medium (MSM); sub cultured in concentrations of 5, 10, 15 and 20μL of electrical transformer fluids were investigated for twenty‐one days period. Physiological changes in terms of biomass increase were monitored by measuring the pH and optical density of the culture medium. From the results obtained, there was observed a general decrease in the pH and  increase in Optical density (O.D). The mean pH and O.D. readings ranged between (4.34‐6.13 and 0.073‐0.386) respectively. The decreased pH could justify for the acidic metabolites produced in the course of utilization of askarel as growth substrates. This study suggested that, the tropical ecosystems can provide exotic bacterial species that are capable of degrading or mineralizing polychlorinated biphenyls and their derivatives from dumpsites and agricultural soils.

Isolation and Characterization of a New Arthrospira Strain

2008 ◽  
Vol 63 (1-2) ◽  
pp. 144-150 ◽  
Author(s):  
Michele Greque de Morais ◽  
Carolina da Cruz Reichert ◽  
Francieli Dalcanton ◽  
Andrei José Durante ◽  
Luís Fernando Marins ◽  
...  
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Rapd Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Arthrospira Platensis ◽  
Central Point ◽  
Filamentous Microorganism ◽  
Isolation And Characterization

A filamentous microorganism, morphologically similar to the cyanobacterium Arthrospira, was isolated from Mangueira Lagoon in Brazil, from which Arthrospira has not previously been isolated. Random amplified polymorphic DNA (RAPD) comparison with the standard Arthrospira platensis strains LEB 52 and Paracas indicated that the organism isolated was an Arthrospira isolate, which we denominated strain LEB 18. The RAPD analysis showed conserved sequences which indicated that the three strains belonged to the same genus, and were all Arthrospira species, but there were sufficient differences between them suggesting that they were separate strains. The strain LEB 18 was cultivated in undiluted Zarrouk medium and in 60% and 20% (v/v) Zarrouk medium diluted with sterilized Mangueira Lagoon water (MLW) using illuminance rates of 32.5, 45.5 and 58.5 μmol m−2 s−1 according to a complete 32 factorial design with a triplicate central point. The strains LEB 52 and Paracas were cultived in the conditions central point. Our new isolate produced the highest specific growth rate (μmax = 0.22 d−1) in 60% Zarrouk medium diluted with MLW and illuminated with 58.5 μmol m−2 s−1 and the highest protein content (86.0% w/w).

Isolation and Characterization of a Novel n-Alkane-Degrading Strain, Acinetobacter haemolyticus AR-46

2007 ◽  
Vol 62 (3-4) ◽  
pp. 285-295 ◽  
Author(s):  
Zoltán Bihari ◽  
Aladár Pettkó-Szandtner ◽  
Gyula Csanádi ◽  
Margit Balázs ◽  
Péter Bartos ◽  
...  
Keyword(s):  
Hydrophobic Surface ◽  
Open Reading Frames ◽  
Substrate Uptake ◽  
Alkane Hydroxylase ◽  
Detailed Report ◽  
Isolation And Characterization ◽  
Acinetobacter Spp ◽  
Acinetobacter Haemolyticus ◽  
Reading Frames

Abstract Strain AR-46, isolated and identified as Acinetobacter haemolyticus, evolutionally distant from the known hydrocarbon-degrading Acinetobacter spp., proved to have excellent longchain n-alkane-degrading ability. This is the first detailed report on an n-alkane-utilizing strain belonging to this species. The preferred substrate is n-hexadecane, with an optimal temperature of 37 °C under aerobic conditions. Five complete and two partial open reading frames were sequenced and correlated with the early steps of monoterminal oxidation-initiated n-alkane mineralization. The encoded protein sequences and the arrangement of these genes displayed high similarity to those found in Acinetobacter sp. M-1, but AR-46 seemed to have only one alkane hydroxylase gene, with a completely different induction profile. Unique behaviour was also observed in n-alkane bioavailability. Substrate uptake occurred through the hydrophobic surface of n-alkane droplet-adhered cells possessing long, thick fimbriae, which were presumed to play a major role in n-alkane solubilization. A majority of the cells was in detached form, with thick, but short fimbriae. These free cells were permanently hydrophilic, unlike the cells of other Acinetobacter strains.

scholarly journals Antitumor Activity of Bacillus natto. V. Isolation and Characterization of Surfactin in the Culture Medium of Bacillus natto KMD 2311

1974 ◽  
Vol 22 (4) ◽  
pp. 938-944 ◽  
Author(s):  
YUKIO KAMEDA ◽  
SADAO OUHIRA ◽  
KATSUHIKO MATSUI ◽  
SHOICHI KANATOMO ◽  
TETSU HASE ◽  
...  
Keyword(s):  
Antitumor Activity ◽  
Culture Medium ◽  
Bacillus Natto ◽  
Isolation And Characterization

Isolation and Characterization of Viridin, a New 65 kDa Antifungal Protein from the Mould Trichoderma viride

1999 ◽  
Vol 380 (10) ◽  
pp. 1243-1245 ◽  
Author(s):  
Jian-Jiang Hao ◽  
Chuan-dong Geng ◽  
Wei-jun Xie ◽  
Zhen-zhen Gong ◽  
Wang-Yi Liu ◽  
...  
Keyword(s):  
High Performance ◽  
Culture Medium ◽  
Basic Protein ◽  
Trichoderma Viride ◽  
Exchange Chromatography ◽  
Antifungal Protein ◽  
Cation Exchange Chromatography ◽  
Isolation And Characterization ◽  
Sds Page

AbstractA new extracellular antifungal protein with a yield of 10 mg per liter was isolated from the culture medium of the mouldTrichoderma viride. The protein, which we named viridin, was purified by carboxymethyl-cellulose cation-exchange chromatography and Superose 12 HR 10/30 high-performance liquid chromatography. Viridin, a basic protein of approximately 65 kDa as determined by SDS-PAGE, inhibits the growth of the cotton pathogenVerticillum dahliae, the IC50being 6 ΜM.

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