A haemagglutinin from the medicinal fungus Cordyceps militaris.
There are only a few reports on agglutinins from ascomycete and medicinal fungi. An HA (haemagglutinin), with an N-terminal amino acid sequence different from those of known lectins, was isolated in the present study from dried fruiting bodies of the medicinal ascomycete fungus Cordyceps militaris. The purification protocol consisted of affinity chromatography, ion-exchange chromatography and gel filtration. The haemagglutinating activity of the HA could not be inhibited by simple sugars or heparin, and was stable over the pH range 2-13 and up to 60 degrees C. Chemical modification of tryptophan and tyrosine residues had no effect. The HA exhibited some antiproliferative activity towards hepatoma (HepG2) cells and inhibited HIV-1 reverse transcriptase (IC50=10 microM). However, it did not exhibit antifungal activity, mitogenic activity towards splenocytes, nitric oxide-inducing activity towards macrophages or RNase activity. The results of the present study add to the meagre information pertaining to agglutinins from ascomycete and medicinal mushrooms. It is revealed in this study that C. militaris HA differs from other ascomycete mushroom HAs in a variety of biochemical characteristics.
Wong
Jack H
JH
Department of Biochemistry, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People's Republic of China.
Wang
Hexiang
H
Ng
Tzi B
TB
D006528:Carcinoma, Hepatocellular / Q000188:drug therapy; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D032661:Cordyceps / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D048690:Fruiting Bodies, Fungal / Q000737:chemistry; D054303:HIV Reverse Transcriptase / Q000378:metabolism; D006388:Hemagglutinins / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D020128:Inhibitory Concentration 50; D008113:Liver Neoplasms / Q000188:drug therapy; D008826:Microbial Sensitivity Tests; D008970:Molecular Weight; D055550:Protein Stability; D012260:Ribonucleases / Q000032:analysis / Q000378:metabolism; D020539:Sequence Analysis, Protein; D013696:Temperature; D014364:Tryptophan / Q000737:chemistry; D014443:Tyrosine / Q000737:chemistry
D006388:Hemagglutinins; D014443:Tyrosine; D014364:Tryptophan; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase; D012260:Ribonucleases