A novel ribonuclease with HIV‐1 reverse transcriptase inhibitory activity purified from the fungus Ramaria formosa

Abstract

A purification protocol that encompassed anion exchange chromatography (EC) on DEAE-cellulose, cation EC on CM-cellulose, anion EC on Q-Sepharose, and fast protein liquid chromatography-gel filtration of Superdex 75 was used to isolate a ribonuclease from dried fruiting bodies of Ramaria formosa. The ribonuclease was unadsorbed on CM-cellulose but adsorbed on both DEAE-cellulose and Q-Sepharose. It displayed a molecular mass of 29-kDa in both gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The ranking of its ribonucleolytic activity toward polyhomoribonucleotides was poly(U) > poly(C) > poly(G) > poly(A). It exhibited a pH optimum of pH 5 and a temperature optimum at 60 °C. The ribonuclease inhibited HIV-1 reverse transcriptase with an IC50 of 3 µM.

Antifungal protein determination for submerged cultures of the medicinal mushroom <i>Ganoderma lucidum</i> (Ganodermataceae) with activity over the phytopathogen fungus Mycosphaerella fijiensis (Mycosphaerellaceae)

“…Regarding ribonucleases, in a study performed by Zhang et al 2014, one ribonuclease was isolated from the mushroom Ramaria formosa, it was proved to have antifungal and antibacterial properties, and an activity in the crude extract of 45.2 U/mg was observed (Zhang et al 2015), which compared to the results obtained in this study is 760 U/mg lower (table ). Another case is the ribosome inactivating protein restrictocin from A. fumigatus and A. restrictus, which demonstrated suppressive activity towards the fungi Alternaria longipes, F. oxysporum, Colletotrichum gloeosporioides, Trichoderma viride and Paecilomyces variotii.…”

Development of peptide inhibitors of HIV transmission

“…Peptide mimics of other RT binding viral proteins, such as a Vpr protein-derived peptide, also hold promise as peptide inhibitors [183] . Other peptide inhibitors for RT include peptides derived from ribonuclease [184] , [185] , polyarginine transporter molecules [186] , N-methylated peptides that bind RNA [187] , protein targeting RTC [188] , and anti-fungal peptides [189] . Similarly to protease and integrase peptide inhibitors, RT peptide inhibitors also face the problem of low potency (high IC50 values) and thus have not advanced to in vivo evaluation or clinical studies.…”

A Ribonuclease Isolated from Wild Ganoderma Lucidum Suppressed Autophagy and Triggered Apoptosis in Colorectal Cancer Cells

“…Though a least two RNases have been reported from G. lucidum , including a 42 kDa RNase ( Wang et al, 2004 ) and an RNase with gene named RNGI30, GLR was dissimilar to any of the reported fungal proteins as judged by molecular weight or MS analysis. However, GLR resembled RNases from Lyophyllum shimeiji ( Zhang et al, 2010 ), Ramaria formosa ( Zhang et al, 2015 ), Russulus virescens ( Wang and Ng, 2003 ), and Thelephora ganbajun ( Wang and Ng, 2004 ) in adsorption on DEAE-cellulose and Q-ion exchangers, and differed from Hypsizigus marmoreus ( Guan et al, 2007 ) and Russula delica RNases ( Zhao et al, 2010 ) which were unadsorbed on DEAE-cellulose.…”