Isolation and characterization of luffacylin,a ribosome inactivating peptide with anti-fungal activity from sponge gourd (Luffa cylindrica) seeds

A purification scheme involving ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, and ion exchange chromatography on CM-Sepharose and Mono S was employed to isolate a peptide with a molecular weight of 7.8kDa from sponge gourd seeds. The peptide, which was designated luffacylin, exhibited an N-terminal sequence with pronounced resemblance to that of the 6.5kDa arginine-glutamate rich polypeptide previously isolated from sponge gourd seeds. Luffacylin inhibited translation in a rabbit reticulocyte lysate system with an IC(50) of 140pM and reacted positively in the N-glycosidase assay for ribosome inactivating proteins. Luffacylin exerted anti-fungal activity against Mycosphaerella arachidicola and Fusarium oxysporum.     

Isolation of allicepin, a novel antifungal peptide from onion (Allium cepa) bulbs.

From the bulbs of the onion Allium cepa, a novel antifungal peptide distinct from the antimicrobial peptide previously reported from onion seeds was isolated. The antifungal peptide, designated allicepin, was purified with a procedure that involved aqueous extraction, ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel and FPLC-gel filtration on Superdex 75. Allicepin was unadsorbed on DEAE-cellulose and adsorbed on Affi-gel blue gel. The molecular weight of allicepin was estimated to be 10 K by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration on Superdex 75. Allicepin exerted an inhibitory activity on mycelial growth in several fungal species including Botrytis cinerea, Fusarium oxysporum, Mycosphaerella arachidicola and Physalospora piricola.     

Purification of allivin,a novel antifungal protein from bulbs of the round-cloved garlic

A novel antifungal protein, designated allivin, was isolated from bulbs of the round-cloved garlic Allium sativum var. round clove with a procedure involving ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-Sepharose and FPLC-gel filtration on Superdex 75. Allivin possessed an N-terminal sequence demonstrating very little similarity to sequences of Allium sativum chitinases and ribosome inactivating proteins. Allivin exhibited a molecular weight of 13 kDa in gel filtration and SDS-polyacrylamide gel electrophoresis. It displayed antifungal activity against Botrytis cinerea, Mycosphaerella arachidicola and Physalospora piricola. It inhibited translation in a cell-free rabbit reticulocyte system with an IC50 of 1.6 microM.     

First isolation of an antifungal lipid transfer peptide from seeds of a Brassica species

An antifungal peptide with a molecular mass of 9412 and an N-terminal sequence exhibiting notable homology to those of lipid transfer proteins was isolated from seeds of the vegetable Brassica campestris. The purification protocol entailed ion exchange chromatography on Q-Sepharose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography by fast protein liquid chromatography (FPLC) on Mono S, and gel filtration by FPLC on a Superdex peptide column. The antifungal peptide was adsorbed on Affi-gel blue gel and Mono S. It inhibited mycelial growth in Fusarium oxysporum and Mycosphaerella arachidicola with an IC(50) value of 8.3 microM and 4.5 microM, respectively. It exhibited dose-dependent binding to lyso-alpha-lauroyl phosphatidylcholine. The present findings constitute the first report on a non-specific lipid transfer protein from the seeds of a Brassica species.     

Protease from bovine spleen with kininogenase activity]

A protease with kininogenase activity at pH 7.5 was isolated from bovine spleen extract by gel filtration and ion exchange chromatography. The protease was found in the fraction with molecular weight lower than 25.000 and was separated from the other neutral SH-dependent protease by chromatography on KM-cellulose. The kininogenase activity was inhibited by DFP and trasylol; soybean trypsin inhibitor had no effect. The protease did not split N-benzoyl-L-arginine ethyl ester and N-benzoyl-D, L-arginine p-nitroanilide.     

Purification and characterization of a ubiquitin-like peptide with macrophage stimulating,antiproliferative and ribonuclease activities from the mushroom Agrocybe cylindracea

A peptide, with a molecular mass of 9.5kDa and demonstrating an N-terminal sequence similar to ubiquitin, was isolated from fruiting bodies of the mushroom Agrocybe cylindracea. The peptide was isolated with a purification protocol involving ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, FPLC-ion exchange chromatography on Mono S and FPLC-gel filtration on Superdex 75. The peptide was unadsorbed on DEAE-cellulose and adsorbed on Affi-gel blue gel and Mono S. It showed antiproliferative activity on leukemia cell line (M1) and hepatoma cell line (HepG2), and enhanced nitric oxide production in murine peritoneal macrophages with a potency comparable to that of lipopolysaccharide. A pH of 6.0 was required for optimal RNase activity. Its RNase activity was stable over the temperature range of 0-60 degrees C. It exerted ribonucleolytic activity preferentially on polyC, much lower activity on polyU, and negligible activity on polyA and polyG.     

Purification and characterization of recombinant human interleukin-1 beta produced in Escherichia coli

Recombinant human interleukin-1 beta (rIL-1 beta) produced in Escherichia coli was purified to homogeneity by a combination of mass ion exchange column chromatography, ion exchange and gel filtration high performance liquid chromatography. The purified rIL-1 beta had a molecular weight of 18 kD on SDS-polyacrylamide gel electrophoresis and an isoelectric point of 6.9 on analytical isoelectric focusing. These values were almost same as those of natural interleukin-1 beta. The amino acid composition and amino acid sequence of the amino terminal region were consistent with those deduced from the cDNA sequence. In addition, the primary structure was confirmed by peptide mapping with lysyl-endopeptidase on reverse phase HPLC. Besides rIL-1 beta with amino terminal Ala, two molecular species, [Met0] rIL-1 beta and [desAla1] rIL-1 beta, were also obtained. Biological and physicochemical properties of the three species of rIL-1 beta were compared.     

Adustin, a small translation-inhibiting polypeptide from fruiting bodies of the wild mushroom Polyporus adusta

A polypeptide, with a molecular mass of 16.5 kDa as determined by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, has been isolated from the mushroom Polyporus adusta. The polypeptide, designated as adustin, inhibited translation in a cell-free rabbit reticulocyte lysate system with an IC50 of 0.34 microM. It was isolated using a protocol that involved ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-Sepharose and fast protein liquid chromatography-gel filtration on Superdex 75. Adustin was unadsorbed on DEAE-cellulose, and adsorbed on Affi-gel blue gel and CM-Sepharose.     

A novel peptide with ribonuclease and translation-inhibitory activities from fruiting bodies of the oyster mushroom Pleurotus ostreatus.

From the fresh fruiting bodies of the oyster mushroom a peptide with a molecular weight of 9 kDa and demonstrating a novel N-terminal sequence GPCYLVAFYESSGRR was isolated. The isolation procedure involved ion exchange chromatography on CM-Sepharose and Mono S. The peptide was adsorbed on both types of chromatographic media. The peptide demonstrated a ribonuclease activity of 650 U/mg toward yeast transfer RNA. It inhibited cell-free translation in a rabbit reticulocyte lysate system with an IC50 of 15 nM.