A novel lectin from mushroom Phellodon melaleucus displays hemagglutination activity, and antitumor activity in a B16 melanoma mouse model

novel lectin (termed PML) was purified from fruiting bodies of the edible mushroom Phellodon melaleucus (division Basidiomycota) by ion exchange, hydrophobic interaction, and gel filtration chromatographies, with overall titer recovery similar to 60% and 20-fold purification. PML displayed hemagglutination activity 13 319 units/mg toward rabbit erythrocytes. SDS-PAGE and gel filtration analyses revealed that PML is a homodimeric lectin with a molecular weight of 28.8 kDa. PML hemagglutination activity was not inhibited by various simple sugars or their derivatives, but was enhanced by cations Ca2+, Mg2+, Zn2+, and Cu2+. The activity was stable in pH range 6-9 and in the temperature range 20-60 degrees C. Circular dichroism (CD) spectroscopic analysis showed that PML was composed primarily of beta-sheets with low alpha-helix content. In a B16 melanoma mouse model, PML treatment significantly inhibited tumor growth, and increased cytokine IL-10 content. Our findings suggest that PML is a potential anticancer therapeutic agent. (c) 2023 Beijing Academy of Food Sciences. Publishing services by Elsevier B.V. on behalf of KeAiCommunications Co., Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).