Category Archives: Science

Mushroom Compound Suppresses Prostate Tumors

ScienceDaily (May 24, 2011) — A mushroom used in Asia for its medicinal benefits has been found to be 100 percent effective in suppressing prostate tumour development in mice during early trials, new Queensland University of Technology (QUT) research shows.

The compound, polysaccharopeptide (PSP), which is extracted from the ‘turkey tail’ mushroom, was found to target prostate cancer stem cells and suppress tumour formation in mice, according to an article written by senior research fellow Dr Patrick Ling in the online journal PLoS ONE, published by the Public Library of Science.

Dr Ling, from the Australian Prostate Cancer Research Centre-Queensland and Institute for Biomedical Health & Innovation (IHBI) at QUT, said the results could be an important step towards fighting a disease that kills 3,000 Australian men a year.

“The findings are quite significant,” Dr Ling said.

“What we wanted to demonstrate was whether that compound could stop the development of prostate tumours in the first place.

“In the past, other inhibitors tested in research trials have been shown to be up to 70 percent effective, but we’re seeing 100 percent of this tumour prevented from developing with PSP.

“Importantly, we did not see any side effects from the treatment.”

Dr Ling said conventional therapies were only effective in targeting certain cancer cells, not cancer stem cells, which initiated cancer and caused the disease to progress.

During the research trial, which was done in collaboration with The University of Hong Kong and Provital Pty Ltd, transgenic mice that developed prostate tumours were fed PSP for 20 weeks.

Dr Ling said no tumours were found in any of the mice fed PSP, whereas mice not given the treatment developed prostate tumours. He said the research suggested that PSP treatment could completely inhibit prostate tumour formation.

“Our findings support that PSP may be a potent preventative agent against prostate cancer, possibly through targeting of the prostate cancer stem cell population,” he said.

He said PSP had been previously shown to possess anti-cancer properties, and ‘turkey tail’ mushrooms (known as Coriolus versicolor or Yun-zhi) had been widely used in Asia for medicinal benefits.

However, Dr Ling said it was the first time it had been demonstrated that PSP had anti-cancer stem cell effects.

Although ‘turkey tail’ mushrooms had valuable health properties, Dr Ling said it would not be possible to get the same benefit his research showed from simply eating them.

A fundraiser has been organised in September to support further tests for the therapeutic potential of PSP against prostate tumours either alone or in combination with other anti-cancer compounds.

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Identification and characterization of novel cytochrome P450 genes from the white-rot basidiomycete, Coriolus versicolor.

Ichinose H, Wariishi H, Tanaka H.

Faculty of Agriculture, Kyushu University, Fukuoka, Japan.

Abstract

Using a reverse-transcription polymerase chain reaction (RT-PCR) technique, cytochrome P450 genes were cloned from the lignin-degrading basidiomycete, Coriolus versicolor. One possible P450 gene was identified, which consisted of 1,672 nucleotides and a poly(A) tail and encoded a deduced protein containing 449 amino acids. The deduced amino acid sequence revealed the presence of the P450 heme-binding motif, strongly suggesting that this protein belongs to the P450 superfamily, then designated CYP512A1. The deduced protein showed sequential similarity to other known P450s from several micro-organisms, such as Aspergillus terreus, Gibberella fujikuroi, and Neurospora crassa, with 30-35% identity. Since the identity of the amino id sequence was less than 40% with any other P450s, this protein was suggested to be the first member of a new family of cytochrome P450. In addition, a differential display RT-PCR analysis showed the expression of the other P450 genes, which were up-regulated by the addition of dibenzothiophene and 4-methyldibenzothiophene-5-oxide. Using the 5′ rapid amplification of cDNA ends method, a 520-nucleotide sequence, including the P450 motif-coding region, was determined for one clone. The deduced protein showed high similarity to CYP512A1 but less than 40% identity with P450s from other organisms. A chemical stress-responsive expression of P450 is suggested for the first time in basidiomycetes.

PMID: 11831480 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/11831480

Effect of synthetic and natural culture media on laccase production by white rot fungi.

Kahraman SS, Gurdal IH.

Department of Science, Faculty of Education, Inonu University, Malatya, Turkey. sskahraman@inonu.edu.tr

Abstract

Laccase is among the major enzymes of white rot fungi involved in lignocellulose degradation. The present paper reports its production by two white rot fungi (Coriolus versicolor, Funalia trogii) under different nutritional conditions. Various synthetic culture media and natural culture medium (molasses wastewater) were tested. Enzyme production in various synthetic culture media, molasses wastewater (vinasse) culture medium and in the absence or presence of cotton stalk supplements showed that vinasse culture medium was a better laccase-inducer medium than the synthetic culture medium. Addition of cotton stalk to various media enhanced the enzyme production. The highest laccase activity was obtained in vinasse culture medium with cotton stalk.

PMID: 11991068 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/11991068

Identification and heterologous expression of the cytochrome P450 oxidoreductase from the white-rot basidiomycete Coriolus versicolor.

Ichinose H, Wariishi H, Tanaka H.

Faculty of Agriculture, Kyushu University, Fukuoka, Japan.

Abstract

A cDNA encoding cytochrome P450 oxidoreductase (CPR) from the lignin-degrading basidiomycete Coriolus versicolor was identified using RT-PCR. The full-length cDNA consisted of 2,484 nucleotides with a poly(A) tail, and contained an open reading frame. The G+C content of the cDNA isolated was 60%. A deduced protein contained 730 amino acid residues with a calculated molecular weight of 80.7 kDa. The conserved amino acid residues involved in functional domains such as FAD-, FMN-, and NADPH-binding domains, were all found in the deduced protein. A phylogenetic analysis demonstrated that C. versicolor CPR is significantly similar to CPR of the basidiomycete Phanerochaete chrysosporium and that they share the same major branch in the fungal cluster. A recombinant CPR protein was expressed using a pET/ Escherichia coli system. The recombinant CPR protein migrated at 81 kDa on SDS polyacrylamide gel electrophoresis. It exhibited an NADPH-dependent cytochrome c reducing activity.

PMID: 12226721 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/12226721

Paul Stamets on 6 ways mushrooms can save the world

Paul Stamets is an American mycologist, author, and advocate of bioremediation and medicinal mushrooms. Stamets is on the editorial board of The International Journal of Medicinal Mushrooms, and is an advisor to the Program for Integrative Medicine at the University of Arizona Medical School, Tucson, Arizona. He is active in researching various properties of mushrooms.

Here is what Paul Stamets on 6 ways mushrooms can save the world:

Bioorganosolve pretreatments for simultaneous saccharification and fermentation of beech wood by ethanolysis and white rot fungi.

Itoh H, Wada M, Honda Y, Kuwahara M, Watanabe T.

Laboratory of Biomass Conversion, Wood Research Institute, Kyoto University, Gokasho, Uji, Kyoto, Japan.

Abstract

Ethanol was produced by simultaneous saccharification and fermentation (SSF) from beech wood chips after bioorganosolve pretreatments by ethanolysis and white rot fungi, Ceriporiopsis subvermispora, Dichomitus squalens, Pleurotus ostreatus, and Coriolus versicolor. Beech wood chips were pretreated with the white rot fungi for 2-8 weeks without addition of any nutrients. The wood chips were then subjected to ethanolysis to separate them into pulp and soluble fractions (SFs). From the pulp fraction (PF), ethanol was produced by SSF using Saccharomyces cerevisiae AM12 and a commercial cellulase preparation, Meicelase, from Trichoderma viride. Among the four strains, C. subvermispora gave the highest yield on SSF. The yield of ethanol obtained after pretreatment with C. subvermispora for 8 weeks was 0.294 g g(-1) of ethanolysis pulp (74% of theoretical) and 0.176 g g(-1) of beech wood chips (62% of theoretical). The yield was 1.6 times higher than that obtained without the fungal treatments. The biological pretreatments saved 15% of the electricity needed for the ethanolysis.

PMID: 12890613 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/12890613

Purification, characterization, and molecular cloning of a pyranose oxidase from the fruit body of the basidiomycete, Tricholoma matsutake.

Takakura Y, Kuwata S.

Plant Breeding and Genetics Research Laboratory, Japan Tobacco, Inc.. Iwata, Shizuoka, Japan. yoshimitsu.takakura@ims.jti.co.jp

Abstract

A new H(2)O(2)-generating pyranose oxidase was purified as a strong antifungal protein from an arbuscular mycorrhizal fungus, Tricholoma matsutake. The protein showed a molecular mass of 250 kDa in gel filtration, and probably consisted of four identical 62 kDa subunits. The protein contained flavin moiety and it oxidized D-glucose at position C-2. H(2)O(2) and D-glucosone produced by the pyranose oxidase reaction showed antifungal activity, suggesting these compounds were the molecular basis of the antifungal property. The V(max), K(m), and k(cat) for D-glucose were calculated to be 26.6 U/mg protein, 1.28 mM, and 111/s, respectively. The enzyme was optimally active at pH 7.5 to 8.0 and at 50 degrees C. The preferred substrate was D-glucose, but 1,5-anhydro-D-glucitol, L-sorbose, and D-xylose were also oxidized at a moderate level. The cDNA encodes a protein consisting of 564 amino acids, showing 35.1% identity to Coriolus versicolor pyranose oxidase. The recombinant protein was used for raising the antibody.

PMID: 14730138 [PubMed – indexed for MEDLINE]Free Article

http://www.ncbi.nlm.nih.gov/pubmed/14730138

Fungal polysaccharopeptide inhibits tumor angiogenesis and tumor growth in mice.

Ho JC, Konerding MA, Gaumann A, Groth M, Liu WK.

Department of Anatomy, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.

Abstract

Angiogenesis is crucial to tumor growth and metastasis, and interruption of this process is a prime avenue for therapeutic intervention of tumor proliferation. The present study has made use of the S180 tumor-bearing mouse model to investigate the polysaccharopeptide, PSP, isolated from the edible mushroom Coriolus versicolor, a herbal medicine known for its anti-angiogenesis properties. Quantitative analysis of microcorrosion casting of the tumor tissue showed more angiogenic features such as dense sinusoids and hot spots, in control (untreated) than in PSP-treated animals. Immunostaining of tumor tissues with antibody against the endothelial cell marker (Factor VIII) demonstrated a positive correlation in that both the vascular density and tumor weight were lower in mice treated with PSP. Morphometric analysis of corrosion casts revealed that, even though the total amount of new vessel production was reduced, the basic tumor type-specific vascular architecture was retained. However, the expression of vascular endothelial cell growth factor (VEGF) in these tumors was suppressed. In conclusion, anti-angiogenesis should be one of the pathways through which PSP mediated its anti-tumor activity.

PMID: 15234192 [PubMed – indexed for MEDLINE]

Pretreatment of bamboo residues with Coriolus versicolor for enzymatic hydrolysis.

Zhang X, Xu C, Wang H.

College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074, PR China. zhangxiaoyu@mail.hust.edu.cn

Abstract

Pretreatment by a white-rot fungus Coriolus versicolor B1 under different conditions and saccharification of bamboo were investigated. The saccharification rate was significantly enhanced and a maximum saccharification rate of 37.0% was achieved after pretreatment. Reducing sugars yield was 223.2 mg/g of bamboo residues, which was 2.34 times that of the raw material. It was feasible to treat bamboo residues with B1 for the saccharification of bamboo.

PMID: 17884661 [PubMed – indexed for MEDLINE]Free Article

http://www.ncbi.nlm.nih.gov/pubmed/17884661

Immune System Genes Show Links to Type 1 Diabetes – By Serena Gordon, HealthDay Reporter

WEDNESDAY, Sept. 8 (HealthDay News) — The exact cause of type 1 diabetes is still unknown, but international researchers have found a link between the blood sugar disorder and a network of immune system genes.

Using a genome-wide association study, the researchers found that a certain group of genes that react in response to viral infections were present in both rats and humans, and that those same genes were also associated with a susceptibility to type 1 diabetes.

“Diseases arise as a result of many genetic and environmental factors through gene networks that cause tissue damage,” explained study senior author Dr. Stuart Cook, the group head of molecular and cellular cardiology at the Medical Research Council Clinical Sciences Centre, and a professor of clinical and molecular cardiology at Imperial College in London.

“We used an approach to identify the major control points’ central command of an inflammatory gene network. This led us to uncover hundreds of new genes that might cause diabetes and one major control gene that controls the whole network,” said Cook.

He added that one of the genes belongs to a class of genes that might make a good target for drug therapy in the future.

Results of the study are published in the Sept. 9 issue of Nature.

Each year, more than 30,000 people are diagnosed with type 1 diabetes, formerly known as juvenile diabetes, according to the Juvenile Diabetes Research Foundation (JDRF). People with type 1 diabetes no longer produce enough of the hormone insulin to effectively use the sugars found in carbohydrate-containing foods. To survive, people with type 1 diabetes must take insulin injections or use an insulin pump for the rest of their lives.

Experts believe the disease is an autoimmune disease, which means that the body’s immune system mistakenly turns against healthy cells, such as the insulin-producing cells in the pancreas, and destroys them. People who develop type 1 diabetes are believed to have a genetic susceptibility to the disease that’s then triggered by something in the environment, possibly a virus.

In the current study, the researchers didn’t initially set out to look for type 1 diabetes genes. They started out by looking at a certain group of genes in rats, in this case a network of genes controlled by a gene called interferon regulatory factor 7 (IRF7). IRF7 is like a master switch that controls the genes in its network. The entire network of genes controlled by IRF7 is called the IRF7-driven inflammatory network (IDIN).

The researchers discovered that when there were differences in IRF7, there were also differences in the way other genes expressed themselves.

Cook and his colleagues then searched for a network of genes in humans that might behave the same way. They found an area on chromosome 13q32 that is controlled by a gene called the “Epstein-Barr virus induced gene 2” (Ebi2). This gene appeared to be the human equivalent of the IRF7 gene in rats.

Within this human version of the IDIN, research found a gene called IFIH1, which has been found in other research to be associated with the development of type 1 diabetes.

“Usually, research starts from the genetics and goes to function. Here, they started with a function — [an immune system reaction] — and were looking for a gene,” explained Marie Nierras, director of research and scientific affairs for the JDRF.

“The value of such a result is that if you can get to the same place using more than one pathway, it tends to support the hypothesis,” she said.

In this case, the hypothesis supported is the idea that type 1 diabetes may be triggered by an immune system response to a virus. However, Nierras stressed that this study doesn’t conclusively prove that a virus is the trigger for type 1 diabetes.

“We know better today that this network of genes is involved, and with a network, you have many targets you can test. This research invites us to plan experiments going forward, and opens up many more questions, like ‘If I disrupt this branch of the network, do I disrupt diabetes?’ Or, ‘If you look back at previous research knowing this study’s results, does that help to better explain previous results?'” said Nierras.

Cook said this type of genome-wide association study can be used for other diseases as well, and that his team is hoping to eventually develop a new drug based on the genetic target they discovered.

More information

Learn more about type 1 diabetes and its causes from the U.S. National Library of Medicine.

SOURCES: Stuart Cook, M.D., Ph.D., group head, molecular and cellular cardiology, the Medical Research Council Clinical Sciences Centre, and professor, clinical and molecular cardiology, Imperial College, London; Marie Nierras, Ph.D., director, research and scientific affairs, Juvenile Diabetes Research Foundation, New York City; Sept. 9, 2010, Nature

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