Release of protoplasts from the galactose oxidase producing mold, Dactylium dendroides

1983 ◽  
Vol 29 (7) ◽  
pp. 763-766 ◽  
Author(s):  
Déa Amaral ◽  
Doroty Kubicki ◽  
Hector F. Terenzi
Keyword(s):  
Growth Medium ◽  
Phosphate Buffer ◽  
Normal Growth ◽  
Galactose Oxidase ◽  
Lytic Enzyme ◽  
Considerable Importance ◽  
Digestive Juice ◽  
Osmotic Stabilizer ◽  
Dactylium Dendroides

Osmotically sensitive protoplasts were released from the mycelium of Dactylium dendroides, using Megalobolinus paranaguensis digestive juice as a lytic enzyme. The conditions for obtaining stable protoplasts were determined. The maximum number of protoplasts was obtained from 15-h growing mycelium, using MgSO4 as osmotic stabilizer, in the presence of 0.015 M Sorensen phosphate buffer, pH 5.6. MgSO4 proved to be of considerable importance in the release of protoplasts in this fungus. Regeneration of the protoplasts was demonstrated in normal growth medium supplemented with 0.8 M mannitol and 2.5% agar.

Functional differentiation of nitrate-reducing isolates regulated by long-term fertilization in a rice paddy soil

2020 ◽  
pp. 1-9
Author(s):  
Xing Chen ◽  
Yi Liu ◽  
Chunmei Liu ◽  
Wenzhao Zhang ◽  
Hongling Qin ◽  
...  
Keyword(s):  
Growth Medium ◽  
Normal Growth ◽  
Rice Paddy ◽  
Functional Differentiation ◽  
Fertilizer Treatment ◽  
Potassium Fertilizer ◽  
Nutritional Conditions ◽  
Nitrate Reducers ◽  
Nitrite Production

Fertilization can cause obvious shifts in nitrate-reducing community composition in agricultural ecosystems; however, little is known about the behaviors and functional characters of isolated nitrate reducers adapted to a specific environment. In this study, 849 nitrate-reducing bacteria were isolated from various fertilization treatments in a long-term paddy field experiment; the isolates were further characterized in functions with both culture-dependent and independent methodologies. The results showed that CK (no fertilizer) treatment had four genera with even relative abundance, whereas the other three treatments had their own predominant genera with Chromobacterium in nitrogen (N) fertilizer, Serratia in NPK (nitrogen, phosphorus, and potassium fertilizer) and Enterobacter in NPKC treatment (NPK plus rice straw). The isolates of Serratia and Enterobacter grew faster and produced significantly more nitrites than those of Chromobacterium and Burkholderia in the normal growth medium, suggesting that the dominant isolates from nutrient-rich environment, such as NPK and NPKC treatments, are better adapted to high nutritional conditions. On the contrary, the strains of Chromobacterium and Burkholderia possessed stronger nitrite production ability in comparison with the isolates of Serratia and Enterobacter in the diluted growth medium, indicating that the selected isolates from CK and N treatments have the capability to develop under nutrient-limiting conditions. Our results indicated that the behaviors and functions of nitrate reducers appears to be important in adapting to their dwelling habitats.

Galactosyl-biomimetic dye-ligands for the purification of Dactylium dendroides galactose oxidase

2002 ◽  
Vol 954 (1-2) ◽  
pp. 137-150 ◽  
Author(s):  
C.F Mazitsos ◽  
D.J Rigden ◽  
P.G Tsoungas ◽  
Y.D Clonis
Keyword(s):  
Galactose Oxidase ◽  
Dactylium Dendroides

scholarly journals Evidence for a pronounced secretion of cyclic AMP by Tetrahymena.

1980 ◽  
Vol 85 (3) ◽  
pp. 910-915 ◽  
Author(s):  
S G Nandini-Kishore ◽  
G A Thompson
Keyword(s):  
Cyclic Amp ◽  
Growth Medium ◽  
Phosphate Buffer ◽  
External Medium ◽  
Active Material ◽  
Tetrahymena Pyriformis ◽  
Unicellular Eukaryote ◽  
Beef Heart ◽  
Nutrient Media ◽  
Complete Hydrolysis

The unicellular eukaryote Tetrahymena pyriformis secretes significant amounts of cyclic AMP into its external medium. Cells transferred from growth medium into any of the following three different non-nutrient media: (a) 5 mM phosphate buffer containing 47 mM NaCl and 1 mM MgSO4, (b) 10 mM Tris, or (c) 1.3 mM Tris containing 1 mM citrate and 1 mM Ca(OH)2, released to the outside almost 60--80% of the total cyclic AMP produced during 2--5 h of incubation. Tris-citrate-Ca+2 medium was chosen for further experiments because of its minimal nonspecific interference in the cyclic AMP radioimmunoassay. The identity of the secreted material recognized as cyclic AMP by radioimmunoassay was confirmed by demonstrating its almost complete hydrolysis with commerical beef heart phosphodiesterase. Furthermore, the radioimmunoassay-active material in the concentrated medium co-chromatographed on paper with [3H]cyclic AMP, as judged by assay of the eluted material. After resuspending cells in Tris-citrate-Ca2+ medium, the extracellular concentration of cyclic AMP rose steadily over a 5-h period, reaching a level equvalent to approximately 35--50 pmol cyclic AMP/10(6) cells vs. an internal cyclic AMP quantity at 5 h of 8--10 pmol/10(6) cells. After 5 h, the level of extracellular cyclic AMP reached a plateau. There was no degradation or uptake of external cyclic AMP by the cells during this period.

scholarly journals Development of in vitro Slow Growth Culture for Yarn (Dioscoreo alata L.)

2012 ◽  
pp. 79-95 ◽  
Author(s):  
Villaluz Acedo ◽  
Catherine Arradaza
Keyword(s):  
Tissue Culture ◽  
Growth Medium ◽  
Slow Growth ◽  
Genetic Erosion ◽  
Normal Growth ◽  
Culture Technique ◽  
In Vitro Conservation ◽  
Maintenance Cost ◽  
Germplasm Collections

Germplasm collections, the lifeblood of breeding programs, are traditionally maintained in the field. Field genebanks are expensive, subject to genetic erosion, and require several quarantine measures for safe movement of genetic materials. These problems are more serious in long-duration, non-flowering and vegetatively propagated crops like yarn. This study aimed to develop a tissue culture technique for in vitro conservation of yarn germplasm. ’VU-2’ and ‘Kinampay’ varieties were used in establishing the in vitro conservation technique which was then tested to other genotypes. With the tissue culture protocol for yarn propagation developed earlier, the plantlets became overgrown after 2-3 months, requiring frequent subculturing and increasing the cost of maintenance and the risk of microbial contamination. Slow growth culture was tested using MS medium added with 0-10 mg/L abscisic acid (ABA) or 0-7% mannitol or sorbitol. Expectedly, plantlet growth slowed down. However, ABA at higher levels increased mortality of cultures while sorbitol was less effective than mannitol in retarding growth. Mannitol at 4% was found to be the best slow growth medium to maintain the plantlets for 13 months, thereby saving at least 4 times the maintenance cost using the normal growth medium. Tissue viability, morphological stability and tuber yield were not affected. Other genotypes (VU-1, VU-3, VU-4, VU-5, PR5, PR7, PR10 and PR11) responded similarly to the slow growth culture condition.

"PROTOPLASTS" FROM PYTHIUM SP. PRL 2142

1967 ◽  
Vol 13 (12) ◽  
pp. 1701-1704 ◽  
Author(s):  
J. H. Sietsma ◽  
D. E. Eveleigh ◽  
R. H. Haskins ◽  
J. F. T. Spencer
Keyword(s):  
Lytic Enzyme ◽  
Enzyme Complex ◽  
Enzyme Preparations ◽  
Streptomyces Spp ◽  
Osmotic Stabilizer ◽  
Enzyme Complexes

Enzyme preparations from two Streptomyces spp. released spherical protoplast-like bodies from the mycelium of Pythium sp. PRL 2142. The enzyme complexes were produced by growing the Streptomyces spp. in the presence of autoclaved Pythium mycelium, and concentrated from the culture mixture by precipitation with acetone (2:1, v/v). The protoplasts were released, from both intercalary and terminal locations on the hyphae, during incubation with the lytic enzyme complex for 24 hours using 0.8 M MgSO4 as an osmotic stabilizer.

Effects of mRg2, a Mixture of Ginsenosides Containing 60% Rg2, on the Ultraviolet B–Induced DNA Repair Synthesis and Apoptosis in NIH3T3 Cells

2007 ◽  
Vol 26 (2) ◽  
pp. 151-158 ◽  
Author(s):  
Se Jin Jeong ◽  
Seol Hee Han ◽  
Don Young Kim ◽  
Jeong Chae Lee ◽  
Hack Soo Kim ◽  
...  
Keyword(s):  
Dna Repair ◽  
Cell Viability ◽  
Growth Medium ◽  
Normal Growth ◽  
Ultraviolet B ◽  
Nuclear Antigen ◽  
Trypan Blue Exclusion ◽  
Repair Synthesis ◽  
Nih3t3 Cells ◽  
Dna Repair Synthesis

Ginseng has been used worldwidely as a traditional medicine of Asian countries for treatment of various diseases including cancer. The purpose of this study was to determine the effect of ginseng saponin mRg2, a mixture of ginsenosides containing 60% Rg2, on the repair and apoptosis of ultraviolet B (UVB)-exposed NIH3T3 cells. When cells were exposed to UVB and then incubated with normal growth medium for 48 h, cell viability, as determined by trypan blue exclusion assay decreased to about 25%. However, when mRg2 was included in the postincubation medium, the UVB-induced loss of cell viability was significantly reduced as compared with that postincubated in normal growth medium. 4,6-diamidino-2-phenylindole (DAPI) staining showed that postincubation of the UVB-exposed cells in medium containing mRg2 significantly reduced the apoptotic nuclear fragmentation. Interestingly, when cells were preincubated with mRg2 for 24 h and then exposed to various doses of UV, the amount of repair synthesis significantly increased as compared with those in cells exposed to UVB alone. Western blot analysis indicated that the mRg2 postincubation after UVB exposure potentiated the level of p53 and p21. The level of Triton nonextractable proliferating cell nuclear antigen (PCNA) also remained elevated by mRg2 postincubation. All these results suggest that mRg2 protects cells against UVB-induced genotoxicity by increasing DNA repair and decreasing apoptosis, in possible association with the modulation of protein levels involved in cell cycle arrest or progression.

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