Modifications of amino acids during ferulic acid-mediated, laccase-catalysed cross-linking of peptides.

Steffensen CL, Stensballe A, Kidmose U, Degn PE, Andersen ML, Nielsen JH.

Department of Food Science, Faculty of Agricultural Sciences, Aarhus University, Research Centre Foulum, Tjele, Denmark. charlotte.l.steffensen@agrsci.dk

Abstract

Mass spectral analysis demonstrated oligomerization of peptides that had been subjected to oxidation catalysed by Trametes (Coriolus) versicolor laccase. Peptide oligomerization occurred only when cysteines or tyrosines were present in the peptides. MS/MS confirmed the cross-linking in tyrosine-containing peptides to be located between tyrosine residues. Ferulic acid mediated oligomerization of cysteine-containing peptides, but prevented cross-linking of tyrosines when used in the same concentration as the peptides. This suggests an antioxidative effect of ferulic acid in relation to tyrosine oxidation, although incorporation of ferulic acid into peptide oligomers was found in some of the tyrosine-containing peptides. No other modifications to amino acid residues by laccase-catalysed oxidation were observed by mass spectroscopy. Thus, it is suggested that oxidative modifications of other amino acids observed in proteins oxidized by laccase are not major reaction products of laccase-catalysed oxidation.

PMID: 19905979 [PubMed – indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/19905979

[Impact of exogenous paraquat on enzyme exudation and biochemical changes of lignin degradation fungi]

Zhao Y, Li J, Chen Y, Huang H, Yu Z.

State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing 210093, China.

Abstract

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.

PMID: 19938450 [PubMed – in process]

http://www.ncbi.nlm.nih.gov/pubmed/19938450

Design of reaction conditions for the enhancement of microbial degradation of dyes in sequential cycles.

Sanghi R, Dixit A, Verma P, Puri S.

Facility for Ecological and Analytical Testing, 302, Southern Laboratories, Institute of Technology, Kanpur-20 8016, India. rsanghi@gmail.com

Abstract

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.

http://www.ncbi.nlm.nih.gov/pubmed/20131593

Immunomodulatory effects of polysaccharopeptide (PSP) in human PBMC through regulation of TRAF6/TLR immunosignal-transduction pathways.

Li W, Liu M, Lai S, Xu C, Lu F, Xiao X, Bao Y.

Department of Clinical Laboratory, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China.

Abstract

Context: Polysaccharopeptide (PSP) was extracted from Coriolus versicolor, and has been proved to be a valuable adjuvant for the combination with chemotherapy or radiotherapy in the treatment of various cancers. Objective: To understand the mechanism of PSP on immunomodulation, we examined gene expression and cytokine secretion associated with immunosignal-transduction signaling in human peripheral blood mononuclear cells (PBMCs). Methods: cDNA microarray and cytokine antibody array were used to identify differential gene expression profiles and cytokines secretion of PBMCs in the presence or absence of PSP for 24 h. The expression of the key genes and proteins related to Toll-like receptor (TLR) signaling and its downstream pathway was determined by RT-PCR or Western blot. Results: Compared with the control group, PSP up-regulated 22 genes expression (such as IFN-gamma, CXCL10, TLR4, TLR5) in 117 genes associated with TLR signaling. Twenty-three of genes (e.g., TLR9, TLR10, SARM1, TOLLIP) related with TLR signaling pathway were down-regulated in PBMCs under PSP treatments. Five of cytokines (GCSF, GM-CSF, IL-1alpha, IL-6, IFN-gamma) were up-regulated more than 1.3 times by PSP. The mRNA levels of TRAM, TRIF, and TRAF6, which are the key molecules of TLR signaling pathway, were markedly increased (P < 0.05). Moreover, the protein level of TRAF6 was also markedly increased (P < 0.01). Conclusions: PSP-regulated gene expression and cytokine secretion related to TLR signaling pathway in human PBMCs. Especially, TRAM-TRIF-TRAF6 subsignaling pathway of TLR may be one of the key associated signaling pathways in the immunomodulation of PSP.

PMID: 20131955 [PubMed – as supplied by publisher]

http://www.ncbi.nlm.nih.gov/pubmed/20131955

Effect of nitrogen sources and vitamins on ligninolytic enzyme production by some white-rot fungi. Dye decolorization by selected culture filtrates

Levin L, Melignani E, Ramos AM.

Lab. de MicologĂ­a Experimental, Dpto. de Biodiversidad y BiologĂ­a Experimental, Fac. Cs. Exactas y Naturales, PROPLAME – PRHIDEB – CONICET, Universidad de Buenos Aires, C1428EHA Ciudad Universitaria, CABA, Argentina. lale@bg.fcen.uba.ar

Abstract

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.

http://www.ncbi.nlm.nih.gov/pubmed/20153961

Investigation of growth responses in saprophytic fungi to charred biomass.

Ascough PL, Sturrock CJ, Bird MI.

SUERC, Scottish Enterprise Technology Park, East Kilbride, UK. p.ascough@suerc.gla.ac.uk

Abstract

We present the results of a study testing the response of two saprophytic white-rot fungi species, Pleurotus pulmonarius and Coriolus versicolor, to charred biomass (charcoal) as a growth substrate. We used a combination of optical microscopy, scanning electron microscopy, elemental abundance measurements, and isotope ratio mass spectrometry ((13)C and (15)N) to investigate fungal colonisation of control and incubated samples of Scots Pine (Pinus sylvestris) wood, and charcoal from the same species produced at 300 degrees C and 400 degrees C. Both species of fungi colonise the surface and interior of wood and charcoals over time periods of less than 70 days; however, distinctly different growth forms are evident between the exterior and interior of the charcoal substrate, with hyphal penetration concentrated along lines of structural weakness. Although the fungi were able to degrade and metabolise the pine wood, charcoal does not form a readily available source of fungal nutrients at least for these species under the conditions used in this study.

PMID: 20229385 [PubMed – in process]

http://www.ncbi.nlm.nih.gov/pubmed/20229385

Polysaccharopeptides derived from Coriolus versicolor potentiate the S-phase specific cytotoxicity of Camptothecin (CPT) on human leukemia HL-60 cells.

Wan JM, Sit WH, Yang X, Jiang P, Wong LL.

Agricultural, Food and Nutritional Sciences Division, School of Biological Sciences, The University of Hong Kong, Pokfulam Road, Hong Kong SAR, China. jmfwan@hkusua.hku.hk.

Abstract

ABSTRACT:

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

http://www.ncbi.nlm.nih.gov/pubmed/20423495

Antimetastatic and immunomodulating effect of water extracts from various mushrooms.

Han SS, Cho CK, Lee YW, Yoo HS.

East-West Cancer Center, College of Oriental Medicine, Daejeon University, Daejeon, Korea.

Abstract

This experiment was conducted to evaluate inhibitory effects against lung metastasis and promotion of splenocytes by water extracts from various mushrooms including Armillaria mellea, Grifola frondosa, Garnoderma frondosa, Codyceps militaris, Hericium erinaceus, Coriolus versicolor, Agaricus Blazei with Lycium Chinense Miller (known as M8). Analysis of carbohydrate using HPTLC showed that beta-glucan and pachyman were some of the major components of M8. Oral administration of M8 resulted in a dose-dependent tendency to inhibit lung metastasis after intravenous injection of colon26-L5 cells. Treatment with M8 resulted in a significant increase of T cell and B cell mitogenic stimuli. The population of CD3, CD19, CD4, and CD8 positive cells increased in a dose dependent manner of M8 administration. However, no significant results were obtained from the population of Mac-1 and NK1.1 positive cells. Oral administration of M8 resulted in the increased production of IFN-gamma and IL-4 by splenocytes stimulated with Con A compared with untreated controls. These results show that M8 has antitumor activities which may be useful as an antimetastatic agent.

PMID: 20633495 [PubMed – in process]

http://www.ncbi.nlm.nih.gov/pubmed/20663037

Regulatory properties of polysaccharopeptide derived from Coriolus versicolor and its combined effect with ciclosporin on the homeostasis of human lymphocytes.

Lee CL, Jiang P, Sit WH, Yang X, Wan JM.

School of Biological Sciences, Kadoorie Biological Sciences Building, The University of Hong Kong, Pokfulam Road, Hong Kong SAR.

Abstract

OBJECTIVES: Lymphocyte homoeostasis is essential in inflammatory and autoimmune diseases. In search of natural fungal metabolites with effects on lymphocyte homoeostasis, we recently reported that polysaccharopeptide (PSP) from Coriolus versicolor exhibited ciclosporin-like activity in controlling aberrant lymphocyte activation. This object of this study was to investigate its effect on lymphocyte homoeostasis. This was done by investigating the mechanistic actions of PSP in relation to ciclosporin by performing cell cycle and cell death analysis of human lymphocytes in vitro.

METHODS: We investigated the effect of PSP in the presence and absence of ciclosporin on cell proliferation, cell cycle, cell death, immunophenotype and cell cycle regulatory proteins in human lymphocytes.

KEY FINDINGS: The data showed that PSP exhibited homoeostatic activity by promoting and inhibiting the proliferation of resting and phytohaemagglutinin (PHA)-stimulated lymphocytes, respectively. PHA-stimulated lymphocytes exhibited G0/G1 cell cycle arrest that was accompanied by a reduction of cyclin E expression with PSP treatment. Both PSP and ciclosporin blocked the reduction of the CD4/CD8 ratio in stimulated lymphocytes. PSP did not induce cell death in human lymphocytes, but the suppression of the Fasreceptor suggested a protective role of PSP against extrinsic cell death signals. These homoeostatic effects were more potent with combined PSP and ciclosporin treatment than with either fungal metabolite alone.

CONCLUSIONS: Collectively, the results reveal certain novel effects of PSP in lymphocyte homoeostasis and suggest potential as a specific immunomodulatory adjuvant for clinical applications in the treatment of autoimmune diseases.

PMID: 20663037 [PubMed – in process]

http://www.ncbi.nlm.nih.gov/pubmed/20663037

Alternating immunochemotherapy of advanced gastric carcinoma: a randomized comparison of carbazilquinone and PSK to carbazilquinone in patients with curative gastric resection.

A total of 103 patients with advanced gastric carcinoma were randomized after curative surgery to receive an alternate administration of carbazilquinone (CQ) and PSK (Krestin) or carbazilquinone alone. Each course of therapies started 1 week after the surgical operation and therapy schedules consisted of 9 courses. In each course of 6 weeks, CQ (2 mg/m2/week) was administered on day 0, 8, and 15. In combined immunochemotherapy group, PSK was given orally in 3-divided doses of 2 g/m2/day from the day of the third CQ administration for consecutive 4 weeks. Estimated survival rate and cumulative survival curve were compared utilizing the data up to 7 years after the operation. There was no overall significant difference in survival rates between the CQ plus PSK group and the CQ alone group, but a group of patients whose disease was classified as S1 + S2(N1-2) survived significantly longer when treated with the combination of CQ and PSK. Neither in more advanced cases (greater than S3 or greater than N3) nor in cancers of early stages, the addition of PSK provided an additive effect. The favorable result obtained in one subgroup treated with PSK, suggests that the use of this agent in treating gastric cancers should be carefully evaluated in terms of serosal infiltration and nodal metastasis.