Department of Microbial Chemistry, College of Pharmacy, Seoul National University, 151-742, Seoul, Korea.
Protoplast fusion between isoleucine-, arginine- and thymidine-requiring auxotroph (lle, Arg, Thy) ofLentinula edodes and arginine-requiring auxotroph (Arg) of Coriolus versicolor has been achieved using 30% polyethylene glycol (M.W. 4000) in 10 mMCaCl(2)-glycine solution (pH 8.0). Fusion hybrids were selected in the 0.6 M sucrose supplemented minimal media on the basis of nutritional complementation with fusion frequency of 7.4×10(-6). The hybrids included both parental and non-parental types in colony morphology, growth rate and isozyme patterns. We succeeded inter-order protoplast fusion between the auxotrophs ofLentinula edodes and Coriolus versicolor overcoming the natural barriers of incompatibility. We examined the characteristics of the hybrids and clarified the fusion process using electron microscopy.
Laboratory of Wood Technology, Faculty of Bioscience Engineering, Ghent University, Gent, Belgium. Jan.VandenBulcke@UGent.be
As wood is prone to fungal degradation, fundamental research is necessary to increase our knowledge aiming at product improvement. Several imaging modalities are capable of visualizing fungi, but the X-ray equipment presented in this article can envisage fungal mycelium in wood nondestructively in three dimensions with submicron resolution. Four types of wood subjected to the action of the white rot fungus Coriolus versicolor (Linnaeus) Quélet (CTB 863 A) were scanned using an X-ray-based approach. Comparison of wood volumes before and after fungal exposure, segmented manually or semiautomatically, showed the presence of the fungal mass on and in the wood samples and therefore demonstrated the usefulness of computed X-ray tomography for mycological and wood research. Further improvements to the experimental setup are necessary to resolve individual hyphae and enhance segmentation.
State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210093, China.
To study the effect of exogenous oxygen, we added water solution of paraquat to 7 d cultures of Coriolus versicolor for the next 148 h. Enzyme exudation and biochemiscal process were investigated on the addition of paraquat. We found that compared with the control (without paraquat), the addition of 30 micromol/L paraquat stimulated the activity of manganese dependent peroxidase (MnP), lignin peroxidase (LiP), and laccases (Lac) 7, 2.5 and 1.3 times, respectively. Also, addition of paraquat enhanced activity of superoxide dismutase (SOD) and catalase (CAT) in the first 48 h. Impact of paraquat on ligninolytic enzymes was significant than that on antioxidant enzyme. Addition of paraquat enhanced phenolic compounds and formaldehyde of cultures too. And concentration of malondialdehyde was increased in the first 24 h. The results showed that addition of paraquat promoted oxidative stress, but the antioxidant systems of the fungal strain are sufficient to prevent mycelia from oxidative stress. As exogenous oxygen, paraquat might be a useful substrate in degradation of lignocellulose.
Facility for Ecological and Analytical Testing, 302, Southern Laboratories, Institute of Technology, Kanpur-20 8016, India. firstname.lastname@example.org
The present study evaluated the potential of white-rot fungal strain Coriolus versicolor to decolorize five structurally different dyes in sequential batch reactors under optimized conditions. The experiments were run continuously for seven cycles of 8 d each. High decolorizing activity was observed even during the repeated reuse of the fungus, especially when the old medium was replaced with fresh medium after every cycle. Biodegradation was the dominating factor as the fungus was able to produce the enzyme laccase mainly, to mineralize synthetic dyes. The nutrients and composition of the medium played important roles in sustaining the decolorisation potential of the fungus. Corncob was found be an easy and cheap substitute for carbon source for the fungus. Glucose consumption by the fungus was in accordance to its decolorisation activity and chemical oxygen demand (COD) reduction.
Lab. de Micología Experimental, Dpto. de Biodiversidad y Biología Experimental, Fac. Cs. Exactas y Naturales, PROPLAME – PRHIDEB – CONICET, Universidad de Buenos Aires, C1428EHA Ciudad Universitaria, CABA, Argentina. email@example.com
The effect of amino acids, complex nitrogen sources and vitamin addition on Trametes trogii, Trametes villosa and Coriolus versicolor var. antarcticus ligninolytic enzyme production, was evaluated. Dye decolorization by their culture filtrates was compared. Glutamic acid followed by peptone, were the best N sources for laccase and manganese peroxidase production. The three fungi produced two laccase isoenzymes (molecular weights from 38 up to 150 kDa); their pattern of production was not affected by medium composition. Although the response was not uniform, vitamin addition sometimes stimulated ligninolytic enzyme production, but never inhibited it. Thiamine induced manganese peroxidase production. T. trogii grown in glutamic acid produced culture filtrates with the highest laccase (188.3 U/ml) and manganese peroxidase activities (4.5 U/ml), rendering the best results in decolorization. These crude filtrates were able to decolorize in half hour (at pH 4.5, 30 degrees C): 13%, 23%, 40%, 46%, 82%, 94% and 95% of Gentian Violet, Xylidine, Congo Red, Malachite Green, Remazol Brilliant Blue R, Indigo Carmine and Anthraquinone Blue, respectively.
Agricultural, Food and Nutritional Sciences Division, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China. firstname.lastname@example.org.
BACKGROUND: Polysaccharopeptide (PSP) from Coriolus versicolor (Yunzhi) is used as a supplementary cancer treatment in Asia. The present study aims to investigate whether PSP pre-treatment can increase the response of the human leukemia HL-60 cells to apoptosis induction by Camptothecin (CPT).
METHODS: We used bivariate bromodeoxyuridine/propidium iodide (BrdUrd/PI) flow cytometry analysis to measure the relative movement (RM) of the BrdUrd positively labeled cells and DNA synthesis time (Ts) on the HL-60 cell line. We used annexin V/PI flow cytometry analysis to quantify the viable, necrotic and apoptotic cells. The expression of cyclin E and cyclin B1 was determined with annexin V/PI flow cytometry and western blotting. Human peripheral blood mononuclear cells were used to test the cytotoxicity of PSP and CPT.
RESULTS: PSP reduced cellular proliferation; inhibited cells progression through both S and G2 phase, reduced 3H-thymidine uptake and prolonged DNA synthesis time (Ts) in HL-60 cells. PSP-pretreated cells enhanced the cytotoxicity of CPT. The sensitivity of cells to the cytotoxic effects of CPT was seen to be the highest in the S-phase and to a small extent of the G2 phase of the cell cycle. On the other hand, no cell death (measured by annexin V/PI) was evident with the normal human peripheral blood mononuclear cells with treatment of either PSP or CPT.
CONCLUSION: The present study shows that PSP increases the sensitization of the HL-60 cells to undergo effective apoptotic cell death induced by CPT. The pattern of sensitivity of cancer cells is similar to that of HL-60 cells. PSP rapidly arrests and/or kills cells in S-phase and did not interfere with the anticancer action of CPT. PSP is a potential adjuvant to treat human leukemia as rapidly proliferating tumors is characterized by a high proportion of S-phase cells.
PMID: 20423495 [PubMed – in process]PMCID: PMC2874562