Trypsin Inhibitor from Edible Mushroom Pleurotus floridanus Active against Proteases of Microbial Origin

Abstract

Protease inhibitors can be versatile tools mainly in the fields of medicine, agriculture and food preservative applications. Fungi have been recognized as sources of protease inhibitors, although there are only few such reports on mushrooms. This work reports the purification and characterization of a trypsin inhibitor from the fruiting body of edible mushroom Pleurotus floridanus (PfTI) and its effect on the activity of microbial proteases. The protease inhibitor was purified up to 35-fold by DEAE-Sepharose ion exchange column, trypsin-Sepharose column and Sephadex G100 column. The isoelectric point of the inhibitor was 4.4, and its molecular mass was calculated as 37 kDa by SDS-PAGE and 38.3 kDa by MALDI-TOF. Inhibitory activity confirmation was by dot-blot analysis and zymographic activity staining. The specificity of the inhibitor toward trypsin was with Ki of 1.043 × 10(-10) M. The inhibitor was thermostable up to 90 °C with maximal stability at 30 °C, active over a pH range of 4-10 against proteases from Aspergillus oryzae, Bacillus licheniformis, Bacillus sp. and Bacillus amyloliquefaciens. Results indicate the possibility of utilization of protease inhibitor from P. floridanus against serine proteases.

Immunomodulatory Activities of a Fungal Protein Extracted from Hericium erinaceus through Regulating the Gut Microbiota

“…FIPs have exhibited many beneficial functions in previous studies, including antitumor (5), antiallergy (6, 7), and the ability to stimulate immune cells to produce cytokines (8, 9). Several proteins as lectins (10), lignocellulolytic enzymes (11–14), protease inhibitors (15, 16), and hydrophobins (17–19) have shown unique features and could offer solutions to several medical and biotechnological problems (such as microbial drug resistance, low crop yields, and demands for renewable energy). These stunning properties along with the absence of toxicity render these biopolymers ideal compounds for developing novel functional foods or nutraceuticals with the increase in consumers’ consciousness and demand for healthy food.…”

Production of mycelial biomass, proteases and protease inhibitors by Ganoderma lucidum under different submerged fermentation conditions

“…Tian and Zhang (2005), when isolating a protein of 38 kDa from the mycelial biomass of G. lucidum, with specificity for proteinase A, also observed a half-affinity interaction for trypsin with a small inhibition activity. Trypsin inhibitors have also been reported in other mushroom species, such as Armillaria mellea, Amanita Phalloides, Abortiporus biennis, Macrolepiota procera, Pleurotus floridanus and Pleurotus ostreatus (Ali et al, 2014;Lukanc et al, 2017;Sales-Campos et al, 2021;Zuchowski et al, 2009). Lim et al (2003) when working with extract of the basidiocarp of G. lucidum, obtained a specific chymotrypsin inhibitory activity of 67.3 UI.mg -1 of protein, being identified four isoforms.…”