H.X. Wang

The immunomodulatory and antitumor activities of lectins from the mushroom Tricholoma mongolicum

TML-1 and TML-2 were two lectins isolated from the mushroom Tricholoma mongolicum. They did not differ appreciably in their pH stability and cationic requirement for hemagglutinating activity. They both stimulated the production of nitrite ions and activated the macrophages in mice. The two lectins were able to inhibit the growth of implanted sarcoma 180 cells by 68.84% and 92.39% respectively. The growth of tumor cells in the mouse peritoneal cavity was also inhibited by the two lectins with TML-2 expressing a greater potency.

Immunomodulatory and antitumor activities of a polysaccharide-peptide complex from a mycelial culture of Tricholoma sp., a local edible mushroom

A polysaccharide-peptide complex (PSPC) with immunomodulatory and antitumor activities was obtained from a submerged mycelial culture of Tricholoma sp., a local edible mushroom. The polysaccharide-peptide complex exhibited a molecular weight of 17 K in gel filtration and a single band after SDS-polyacrylamide gel electrophoresis. It was characterized by non-adsorption on both DEAE-Sepharose CL-6B and CM-cellulose. It could activate the macrophages, stimulate the proliferation of T-cells, and inhibit the growth of sarcoma 180 in mice. It possessed more potent immunomodulatory and antitumor activities than Coriolus versicolor polysaccharopeptide (PSP) and deserves to be studied as a potential agent for immunomodulation and cancer therapy.

Isolation and characterization of velutin, a novel low-molecular -weight ribosome-inactivating protein from winter mushroom (Flammulina velutipes) fruiting bodies

From the fruiting bodies of the edible mushroom Flammulina velutipes a single-chained ribosome inactivating protein with a molecular weight of 13.8 kDa was isolated with a procedure involving ion exchange chromatography on DEAE-cellulose and SP-Sepharose and affinity chromatography on Affi-gel blue gel. The protein was novel in that it possessed a molecular weight lower than those of previously reported RIPs and that it was capable of inhibiting human immunodeficiency virus (HIV-1) reverse transcriptase, beta-glucosidase and beta-glucuronidase. Its N-terminal sequence exhibited a certain degree of similarity to those of plant ribosome inactivating proteins.

Polysaccharide—peptide complexes from the cultured mycelia of the mushroom coriolus versicolor and their culture medium activate mouse lymphocytes and macrophages

The aim of this study was to investigate the effects of the mushroom Coriolus versicolor on cells of the immune system. The cultured mycelia of the mushroom Coriolus versicolor and their culture medium were separately extracted with boiling water. The resulting polysaccharopeptide preparations were designated intramycelial (IM) and extramycelial materials (EM), and were separated by gel filtration before determining their effects on lymphocytes and macrophages in vitro and in vivo. After gel filtration on Sepharose 6B, only a single peak with a molecular weight of 13-19 KDa was obtained. Gel filtration of IM and EM on Sephadex G-50 revealed the presence of a larger peak of 28 KDa (from IM) and 15 KDa (from EM) and a smaller peak of 3.5 KDa. IM, EM and their large molecular peaks enhanced the mitogenic response of T-cells from BALB/c mice in vitro. Splenocytes from C57BL/6 mice pre-treated by force-feeding with IM and EM demonstrated an augmented mitogenic response to Con A. The macrophages of C57BL/6 mice that had been pre-treated with IM or EM showed an enhanced production of nitrite ions. The results indicate that both mouse lymphocytes and macrophages were activated by preparations of polysaccharopeptide from cultured mycelia and culture medium of C. versicolor. However, no direct cytotoxic activity against fibroblasts, hepatoma cells and choriocarcinoma cells could be demonstrated.

Isolation of lilin, a novel arginine- and glutamate-rich protein with potent antifungal and mitogenic activities from lily bulbs

From the dried bulbs of the lily (Lilium brownii), a protein with strong antifungal and mitogenic activities was isolated. It also exhibited an inhibitory action on the activity of HIV-1 reverse transcriptase. The protein was single-chained and possessed a molecular weight of 14.4 kDa and an N-terminal sequence distinct from chitinases and antimicrobial proteins of garlic, leek and onion which belong to a family closely related to lily. However, there was a small degree of resemblance to cyclophilins and a considerable extent of identity to the 6.5 kDa arginine/glutamate-rich polypeptide from Luffa cylindrica seeds. A nearly homogeneous preparation was obtained after the extract was fractionated on DEAE-cellulose and Affi-gel Blue gel since subsequent chromatography on Mono S and Superdex 75 both yielded a single peak.

Lectin activity in fruiting bodies of the edible mushroom Tricholoma mongolicum

This study was undertaken to ascertain the existence and some of the characteristics of lectin in the fruiting bodies of the edible mushroom Tricholoma mongolicum. The fractionation procedure utilized entailed aqueous extraction, (NH4)2SO4 precipitation, dialysis, ion exchange chromatography on DEAE‐Sepharose and gel filtration on Sephadex G‐100. A similar procedure has been successfully employed for isolating lectins from cultured mycelia of the same species. It was found that the fruiting body lectin could not be purified with the same facility as the mycelial lectins. Although lectins from both fruiting bodies and cultured mycelia were adsorbed on DEAE‐Sepharose and possessed similar carbohydrate specificities, the fruiting body lectin was adsorbed on ConA‐Sepharose and hence probably glycoprotein in nature whereas the mycelial lectins are unglycosylated proteins.

STUDIES ON PURIFICATION OF A LECTIN FROM FRUITING BODIES OF THE EDIBLE SHIITAKE MUSHROOM LENTINUS EDODES

Abstract A lectin, with a specificity for N-acetylgalactosamine and N-acetylglucosamine and a molecular weight of 43 kDa, was isolated from fruiting bodies of the edible shiitake mushroom Lentinus edodes. The purification procedure entailed extraction with aqueous buffer, ammonium sulfate precipitation, gel filtration on Sephadex G-100 and affinity chromatography on N-acetylgalactosamine-agarose. The lectin was unique in that it was tenaciously bound on anion exchangers including DEAE-cellulose, DEAE-Sepharose, DEAE-Sephadex, Q-Sepharose, Dowex and PEI-cellulose and also on hydroxyapatite and phenyl Sepharose. It was largely unadsorbed on cation exchangers including CM-cellulose, CM-Sepharose, SP-Sepharose and Amberlite, and also on protein G-Sepharose, Red Sepharose and Affi-gel Blue gel, wheat germ lectin-Sepharose and p-aminophenyl- d -glucopyranoside agarose.

A protein with inhibitory activity on cell-free translation from cultured mycelia of the edible mushroom Tricholoma lobayense

Cultured mycelia of the edible mushroom Tricholoma lobayense were extracted with cold saline. Proteins were precipitated from the extract by addition of (NH4)2SO4. The precipitate was dissolved and dialyzed before ion exchange chromatography on DEAE-cellulose. Ability to inhibit translation in a rabbit reticulocyte lysate was located in the unadsorbed fraction which was then subjected to affinity chromatography on Affi-gel Blue gel. The strongest activity was again retained by the unadsorbed fraction. Ion exchange chromatography on CM-cellulose resulted in fractionation of this fraction into an unadsorbed and two adsorbed peaks. Cell-free translation inhibitory activity was concentrated in the fraction eluted with 100 mM NaCl in 10 mM NH4OAc (pH 5.4). The translation-inhibitory protein possessed a molecular weight of 30 kDa as estimated by gel filtration using a fast protein liquid chromatography system and sodium dodecyl sulfate-polyacrylamide gel electrophoresis.