75
18.1 mM, respectively. It was devoid of hemagglutinating, deoxyribonuclease, ribonuclease, and protease inhibitory activities (Wang and Ng 2006).
A peptide called isarfelin was isolated from the mycelia of Isaria felina; this
peptide showed inhibitory activity on mycelial growth in Rhizoctonia solani and
Sclerotinia sclerotiorum and insecticidal activity against Leucania separata.
However, it was devoid of activity toward several bacterial species including
Bacillus subtilis, Escherichia coli, and Staphylococcus aureus (Guo et al. 2005a, b).
5.5 Ribosome-Inactivating Proteins
Ribosome-inactivating proteins (RIPs) are enzymes that act by inactivating ribosomes by removing one or more adenosine residues from rRNA. A novel RIP isolated from fruiting bodies of the mushroom Hypsizygus marmoreus with a molecular
mass of 20 kDa was designated hypsin. This protein showed inhibitory activity
against mycelial growth of Mycosphaerella arachidicola, Physalospora piricola,
Fusarium oxysporum, and Botrytis cinerea, among others. Translation in the rabbit
reticulocyte lysate system and HIV-1 reverse transcriptase activity was inhibited
with IC 50 of 7 nM and IC 50 of 8 μM, respectively. Antiproliferative activity against
mouse leukemia cells and human leukemia and hepatoma cells was observed. Only
40% of the translation-inhibitory activity was lost after heating at 100 °C for 10 min
and no loss of this activity was observed after brief treatment with trypsin (Lam and
Ng 2001a).
Hypsin from Hypsizygus marmoreus and velutin from Flammulina velutipes are
two RIPs and their teratogenicity was evaluated using microinjection and postimplantation whole-embryo culture. Hypsin at 2.5 μM induced abnormal embryonic
development during the organogenesis period from E8.5 to E9.5. There was an
increase in the total number of abnormal embryos related to dosage increase, a drop
in the final somite number, and a rise of abnormal structures. Open cranial neural
tube, abnormal branchial arches, absence of forelimb buds, and twisted body axis
were detected, while the otic and optic placodes were less affected. Histological
study of the abnormal embryos revealed that the increase of cell death was correlated with abnormal structures, suggesting that induction of cell death by hypsin
may account for its teratogenicity. Velutin did not exert any adverse influence on
mouse development (Ng et al. 2010).
A novel RIP from the fruiting bodies of the mushroom Lyophyllum shimeji was
isolated. The protein, designated lyophyllin, showed antifungal activity against
Physalospora piricola and Coprinus comatus. Its molecular mass was 20 kDa and
possessed an N-terminal sequence with some similarity to those of plant RIPs. It
inhibited translation in rabbit reticulocyte lysate (IC 50 of 1 nM), thymidine uptake
by murine splenocytes (IC 50 of 1 μM), and HIV-1 reverse transcriptase activity (IC 50
of 7.9 nM). Lyophyllin did not manifest ribonuclease or hemagglutinating activity.
In the same report, an antifungal protein called Lyophyllum antifungal protein
(LAP) was first isolated from Lyophyllum shimeji. Its molecular mass was of 14 kDa
5 Fungal Productions of Biological Active Proteins
18.1 mM, respectively. It was devoid of hemagglutinating, deoxyribonuclease, ribonuclease, and protease inhibitory activities (Wang and Ng 2006).
A peptide called isarfelin was isolated from the mycelia of Isaria felina; this
peptide showed inhibitory activity on mycelial growth in Rhizoctonia solani and
Sclerotinia sclerotiorum and insecticidal activity against Leucania separata.
However, it was devoid of activity toward several bacterial species including
Bacillus subtilis, Escherichia coli, and Staphylococcus aureus (Guo et al. 2005a, b).
5.5 Ribosome-Inactivating Proteins
Ribosome-inactivating proteins (RIPs) are enzymes that act by inactivating ribosomes by removing one or more adenosine residues from rRNA. A novel RIP isolated from fruiting bodies of the mushroom Hypsizygus marmoreus with a molecular
mass of 20 kDa was designated hypsin. This protein showed inhibitory activity
against mycelial growth of Mycosphaerella arachidicola, Physalospora piricola,
Fusarium oxysporum, and Botrytis cinerea, among others. Translation in the rabbit
reticulocyte lysate system and HIV-1 reverse transcriptase activity was inhibited
with IC 50 of 7 nM and IC 50 of 8 μM, respectively. Antiproliferative activity against
mouse leukemia cells and human leukemia and hepatoma cells was observed. Only
40% of the translation-inhibitory activity was lost after heating at 100 °C for 10 min
and no loss of this activity was observed after brief treatment with trypsin (Lam and
Ng 2001a).
Hypsin from Hypsizygus marmoreus and velutin from Flammulina velutipes are
two RIPs and their teratogenicity was evaluated using microinjection and postimplantation whole-embryo culture. Hypsin at 2.5 μM induced abnormal embryonic
development during the organogenesis period from E8.5 to E9.5. There was an
increase in the total number of abnormal embryos related to dosage increase, a drop
in the final somite number, and a rise of abnormal structures. Open cranial neural
tube, abnormal branchial arches, absence of forelimb buds, and twisted body axis
were detected, while the otic and optic placodes were less affected. Histological
study of the abnormal embryos revealed that the increase of cell death was correlated with abnormal structures, suggesting that induction of cell death by hypsin
may account for its teratogenicity. Velutin did not exert any adverse influence on
mouse development (Ng et al. 2010).
A novel RIP from the fruiting bodies of the mushroom Lyophyllum shimeji was
isolated. The protein, designated lyophyllin, showed antifungal activity against
Physalospora piricola and Coprinus comatus. Its molecular mass was 20 kDa and
possessed an N-terminal sequence with some similarity to those of plant RIPs. It
inhibited translation in rabbit reticulocyte lysate (IC 50 of 1 nM), thymidine uptake
by murine splenocytes (IC 50 of 1 μM), and HIV-1 reverse transcriptase activity (IC 50
of 7.9 nM). Lyophyllin did not manifest ribonuclease or hemagglutinating activity.
In the same report, an antifungal protein called Lyophyllum antifungal protein
(LAP) was first isolated from Lyophyllum shimeji. Its molecular mass was of 14 kDa
5 Fungal Productions of Biological Active Proteins