1,720,991 research outputs found
M. Fortina, Cassandro, re di Macedonia, 1965
No full textBriant Pierre. M. Fortina, Cassandro, re di Macedonia, 1965. In: Revue des Études Anciennes. Tome 75, 1973, n°3-4. p. 420
Le alterazioni di natura microbiologica e nuovi sistemi di valutazione per gli studi di shelf life
No full textSITE-SPECIFIC RESTRICTION ENDONUCLEASES IN BACILLUS-LICHENIFORMIS
No full textWe systematically studied site-specific restriction endonucleases in Bacillus licheniformis strains and detected endonuclease activity in 25 of 217 strains tested. Three different activities were obtained. One of these activities detected in 21 strains was the most representative within the species and produced a banding pattern, after digestion of A DNA, identical to that seen with ClaI. Two other strains isolated from soil samples from China and USA were found to produce a DNA-cleaving enzyme with the same recognition sequence as BsaI. One producer strain, isolated from a Peruvian soil sample, showed to possess a mixture of two isoschizomers, ClaI and BsaI. Finally, one strain produced an endonuclease activity, not previously described in B. licheniformis, that showed the same recognition sites as Bsu361
PROTEINASE PRODUCTION BY HALOPHILIC ISOLATES FROM MARINE-SEDIMENTS
No full textTwenty-one strains of spore-forming bacteria were isolated from marine sediments of the Tyrrhenian seaboard (Livorno, Italy) and identified asBacillus licheniformis by their morphological, physiological and biochemical characteristics. All strains were able to grow at 15% NaCl and on media prepared with 100% seawater. In these conditions 75% of the strains were able to produce a bacitracin-like antibiotic and 100% of the strains showed proteolytic activity. Particularly, all strains showed proteinase production with an activity optimum at pH 8.5 and 60°C. Three strains produced high levels of proteolytic activity only when cultured in the presence of seawater
Production in sea-water of thermostable alkaline proteases by a halotolerant strain of Bacillus licheniformis
No full textA halotolerant strain of Bacillus licheniformis, previously isolated from marine sediments, produced high protease activity during the early stationary phase of growth. The use of sea-water in the fermentation medium enhanced the production of this activity of 150%. After a partial purification, three different proteolytic enzymes could be detected, which were alkaline serine proteases, exhibiting optimal activity at pH 9.0 and at 70°C. The proteases were activated by NaCl, with a two, three-fold increase in activity and were stable in presence of 0.7% NaBO3, 0.5% NaClO and 3% H2 O2
Mapping of two plasmids from Lactobacillus helveticus ILC 54, plasmid curing and preliminary studies on their involvement in lactose metabolism and peptidase activity
No full textTwo plasmids isolated from Lactobacillus helveticus strain ILC 54 were analysed by restriction digestion. A restriction map of the 14.3 and 5.6 kb plasmids is presented. Plasmid-curing studies suggest that these plasmids are involved in lactose metabolism and peptidase activity
Identification of spore-forming strains involved in biodegradation of acifluorfen
No full textWe isolated and identified four spore-forming bacteria from activated sludges and soil, three of which were able to degrade acifluorfen. Biochemical characteristics, DNA base composition and DNA-DNA homology indicated that the degrading strains belonged to the species Bacillus thuringiensis, Clostridium perfringens and Clostridium sphenoides. The fourth strain, identified as C. sphenoides and showing the same characteristics of the corresponding degrading strain, was unable to metabolize acifluorfen. Thus, the plasmid content of these strains was analysed to study the possible correlation between the presence of extrachromosomal elements and the ability to degrade this herbicide
PROPERTIES OF 2 PECTIN LYASES PRODUCED BY AUREOBASIDIUM-PULLULANS LV-10
No full textTwo pectic lyases, L1 and L2, from culture liquids of Aureobasidium pullulans LV 10 were partially purified by ultrafiltration, CM-Sepharose 6B, DEAE-cellulose and/or Sephadex G 100 column chromatography, and characterized. L1 and L2 showed optimum activity at pH 5 and 7.5 respectively, and at 40°C. The molecular weights of the enzymes determined by gel filtration were estimated to be 89000 1000 and 55000 1000 for L1 and L2 respectively. Both lyases were activated by Ca2+ ions. L1 attacked highly esterified pectins, L2 attacked low methoxy-pectins in preference to polygalacturonic acid
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