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Medical Studies

Isolation of mRNAs induced by a hazardous chemical in white-rot fungus, Coriolus versicolor, by differential display.

White-rot fungus Coriolus versicolor, a ligninolytic basidiomycete, has been studied because of its ability to degrade hazardous chemicals. In this study, we searched for genes that are induced by a hazardous chemical using the mRNA differential-display technique and C. versicolor IFO30340 that has been exposed to pentachlorophenol (PCP). Five cDNA fragments were cloned and the DNA sequences of two fragments were analyzed in further detail. The clones corresponded to novel genes that have not previously been identified in C. versicolor. One of the cDNAs exhibited strong sequence homology to the gene for an enolase and the other exhibited homology to a heat shock protein. The expression of the two genes was up-regulated in PCP-treated C. versicolor.[…]

Polysaccharopeptide from the mushroom Coriolus versicolor possesses analgesic activity but does not produce adverse effects on female reproductive or embryonic development in mice.

1. Coriolus versicolor polysaccharopeptide has been reported to exert immunomodulatory and antitumor actions. The present study showed that it exhibits analgesic activity in the hot-plate test upon intraperitoneal administration to ICR mice. 2. It did not affect ovarian steroidogenesis, ovulation and midterm gestation in mice. It did not exert an adverse effect on mouse embryonic development either, as evidenced by the lack of an effect on somite number, axial length and the incidence of abnormalities in heartbeat, yolk sac circulation, optic vesicle, otic vesicle, shape of body axis, forelimb buds, branchial apparatus, cranial neural tube and head size. 3. Its analgesic activity would add to its attribute as an immunomodulatory and antitumor drug.[…]

Effects of OK-432 (picibanil) on the estrogen receptors of MCF-7 cells and potentiation of antiproliferative effects of tamoxifen in combination with OK-432.

OK-432 (picibanil), a streptococcal preparation, has a strong biological response modifier (BRM) function and is expected to produce clinical improvement and prolongation of survival in treated cancer patients in Japan. We were interested in whether OK-432 augments estrogen receptor (ER) levels in breast cancer. To investigate the effect of the BRMs on cellular growth and the characteristics of ER and progesterone receptors (PgR) in the human breast cancer cell line MCF-7, we used OK-432, Krestin (PSK), a protein-bound polysaccharide extracted from Coriolus versicolor, and lentinan, a fungal branched (1…3)-beta-D-glycan. OK432 and PSK dose dependently inhibited DNA synthesis of MCF-7 cells, and the 50% inhibitory concentrations of OK-432 and PSK were 1.2 KE (klinische Einheit, clinical unit)/ml and 200 micrograms/ml, respectively. Lentinan showed no direct anticancer effect in vitro. We found that OK-432 induced a 2-fold increase in ER levels in MCF-7 cells at 0.005 KE/ml, but not in PgR. Lentinan and low-dose PSK did not change ER or PgR levels, but high-dose PSK decreased ER and PgR. We also studied the combined effect of OK-432 and antiestrogens, tamoxifen (TAM) and DP-TAT-59. The combined treatment with OK-432 and TAM showed an additive inhibitory effect on MCF-7 cells. These results suggest that OK-432 may augment the therapeutic effect of TAM in breast cancer.[…]

Cloning and sequencing of a second laccase gene from the white-rot fungus Coriolus versicolor.

A second laccase gene, CVLG1, was isolated from Coriolus versicolor. CVLGI encodes a precursor protein of 526 amino acids which contains a 23-amino acid signal sequence, and the coding region is interrupted by 11 introns. The number of potential N-glycosylation sites in this product is 12 and the greatest among that of polyporales laccases. Moreover, this protein shares about 70% homology with other polyporales laccases. Genomic Southern analysis showed that C. versicolor laccases are encoded by more than four genes including CVLG1 and a transposed allele of this gene.[…]

Blue and yellow laccases of ligninolytic fungi.

Extracellular laccases from submerged cultures of Coriolus versicolor BKM F-116, Panus tigrinus 8/18, Phlebia radiata 79 (ATCC 64658), Phlebia tremellosa 77-51 and from cultures of Pa. tigrinus 8/18, Ph. radiata 79 and Agaricus bisporus D-649 grown on wheat straw (solid-state fermentation) were purified. All enzymes from submerged cultures had a blue colour and characteristic absorption and EPR spectra. Laccases from the solid-state cultures were yellow-brown and had no typical blue oxidase spectra and also showed atypical EPR spectra. Comparison of N-terminal amino acid sequences of purified laccases showed high homology between blue and yellow-brown laccase forms. Formation of yellow laccases as a result of binding of lignin-derived molecules by enzyme protein is proposed.[…]

A review of research on the protein-bound polysaccharide (polysaccharopeptide, PSP) from the mushroom Coriolus versicolor (Basidiomycetes: Polyporaceae).

1. Protein-bound polysaccharides, designated as PSK and PSP, have been isolated from the CM-101 strain and the COV-1 strain, respectively, of the mushroom Coriolus versicolor. This article aims at summarizing existing research findings about PSP since information on PSK is well documented. 2. PSP possesses a molecular weight of approximately 100 kDa. Glutamic and aspartic acids are abundant in its polypeptide component, whereas its polysaccharide component is made up of monosaccharides with alpha-1,4 and beta-1,3 glucosidic linkages. The presence of fucose in PSK and rhamnose and arabinose in PSP distinguishes the two protein-bound polysaccharides, which are otherwise chemically similar. 3. PSP is classified as a biological response modifier. It induces, in experimental animals, increased gamma-interferon production, interleukin-2 production, and T-cell proliferation. It also counteracts the depressive effect of cyclophosphamide on white blood cell count, interleukin-2 production and delayed-type hypersensitivity reaction. Its antiproliferative activity against tumor cell lines and in vivo antitumor activity have been demonstrated. A small peptide with a molecular weight of 16-18 kDa originating from PSP has been produced with antiproliferative and antitumor activities. 4. PSP administered to patients with esophageal cancer, gastric cancer and lung cancer, and who are undergoing radiotherapy or chemotherapy, helps alleviate symptoms and prevents the decline in immune status.[…]

Dietary supplementation with mushroom-derived protein-bound glucan does not enhance immune function in young and old mice.

Decline in immune response is a well-documented age-associated biological change. Protein-bound polysaccharides (PSP) are biological response modifiers and have been shown to have immunoenhancing and antitumor effects. This study was conducted to examine the effect of dietary supplementation with PSP-containing extract derived from mycelia of Coriolus versicolor on in vitro and in vivo indices of immune function of young and old mice. Young (5 mo) and old (23 mo) C57BL/6NIA mice were fed purified diets containing 0, 0.1, 0.5 or 1.0% PSP for 1 mo at which time indices of immune function were measured. PSP supplementation had no significant effect on mitogenic response to concanavalin A (Con A), phytohemagglutinin (PHA) or lipopolysaccharide (LPS), or on production of interleukin (IL)-1, IL-2, IL- 4 and prostaglandin E2 (PGE2). Of the in vivo indices of immune function tested, old mice fed 1.0% PSP had significantly higher delayed-type hypersensitivity (DTH) response than those fed 0% PSP. No significant effect of PSP was observed on the DTH response of young mice. The antibody response to sheep red blood cells was not significantly influenced by PSP in young or old mice. These results suggest that PSP-containing extract from mycelia of Coriolus versicolor might have a modest immunoenhancing effect in aged mice, but not in young mice.[…]

Oxidative biodegradation of an anthraquinone dye, pigment violet 12, by Coriolus versicolor.

Nagoya Municipal Industrial Research Institute, Japan.[…]

Glucose 1- and 2-oxidases from fungal strains: isolation and production of monoclonal antibodies.

Monoclonal antibodies (Mabs) against purified glucose 2-oxidase (EC 1.1.3.10) from Coriolus versicolor were raised by hybridoma technology using Sp2/0 myeloma cells as a fusion partner. Hybrid growth was observed in 42% of culture wells and 30% of these (i.e. 30 culture wells) contained anti-glucose 2-oxidase activity. Three positive wells containing hybrid cell lines were selected and cloned twice by the limiting dilution method and two hybridoma clones (E1A5 and E1A6) secreting Mabs were selected at random for purification and characterisation purposes. Both cell lines secreted Mabs of IgM class which were purified by gel filtration chromatography on a Sephacryl S-200 column with a final recovery of 80% and a purification factor of 16. The purified preparations were apparently homogeneous on native PAGE running with a M(r) of 950 kDa. Mabs were highly specific for glucose 2-oxidase as determined by Western blotting. These Mabs also crossreacted with glucose 1- and 2-oxidases from other fungal sources (Phanerochaeta chrysosporium, Penicillium amagasakiense and Aspergillus niger) as determined by Western blotting and by ELISA. Both glucose 1- and 2-oxidases from C. versicolor, P. chrysosporium, P. amagasakiense and A. niger were purified by hydrophobic interaction chromatography on Sepharose 4B-triazine dye with a recovery of enzyme activity in the range 85-92%. Purified preparations of glucose oxidases from fungal strains were apparently homogeneous on native PAGE. Glucose 2-oxidases were more hydrophobic than glucose 1-oxidases as determined by their chomatographic behaviour on Sepharose 4B-Cibacron Red G-E which could be used to study their roles in lignin biodegradation.[…]

Involvement of interleukin-2 in analgesia produced by Coriolus versicolor polysaccharide peptides.

The analgesia produced by PSP is mediated by IL-2 which is activated by PSP and interacts with IL-2 receptors in the MBH.[…]