Dolichin, a new chitinase-like antifungal protein isolated from field beans (Dolichos lablab)

Preliminary Evaluation of Lablab purpureus Phytochemicals for Anti-BoHV-1 Activity Using In Vitro and In Silico Approaches

Lablab purpureus from the Fabaceae family has been reported to have antiviral properties and used in traditional medical systems like ayurveda and Chinese medicine and has been employed to treat a variety of illnesses including cholera, food poisoning, diarrhea, and phlegmatic diseases. The bovine alphaherpesvirus-1 (BoHV-1) is notorious for causing significant harm to the veterinary and agriculture industries. The removal of the contagious BoHV-1 from host organs, particularly in those reservoir creatures, has required the use of antiviral drugs that target infected cells. This study developed LP-CuO NPs from methanolic crude extracts, and FTIR, SEM, and EDX analyses were used to confirm their formation. SEM analysis revealed that the LP-CuO NPs had a spherical shape with particle sizes between 22 and 30 nm. Energy-dispersive X-ray pattern analysis revealed the presence of only copper and oxide ions. By preventing viral cytopathic effects in the Madin-Darby bovine kidney cell line, the methanolic extract of Lablab purpureus and LP-CuO NPs demonstrated a remarkable dose-dependent anti-BoHV-1 action in vitro. Furthermore, molecular docking and molecular dynamics simulation studies of bio-actives from Lablab purpureus against the BoHV-1 viral envelope glycoprotein disclosed effective interactions between all phytochemicals and the protein, although kievitone was found to have the highest binding affinity, with the greatest number of interactions, which was also validated with molecular dynamics simulation studies. Understanding the chemical reactivity qualities of the four ligands was taken into consideration facilitated by the global and local descriptors, which aimed to predict the chemical reactivity descriptors of the studied molecules through the conceptual DFT methodology, which, along with ADMET finding, support the in vitro and in silico results.

Combined Omics Analysis Further Unveils the Specific Role of Butyrate in Promoting Growth in Early-Weaning Animals

Abnormal mutations in the microbial structure of early-weaning mammals are an important cause of enteritis. Based on the multiple known beneficial functions of butyrate, we hypothesized that butyrate would alleviate the imbalance of intestinal homeostasis induced by early weaning in animals. However, the mechanisms of action between butyrate and intestinal microbes are still poorly explored. In this study, we aimed to investigate whether butyrate exerts beneficial effects on the structure of the intestinal flora of weanling rabbits and their intestinal homeostasis, growth and development, and we attempted to elucidate the potential mechanisms of action through a combined omics analysis. We found that dietary butyrate upregulated the transcription of tight junction-related proteins in the epithelial barrier and improved the intestinal microbial structure by suppressing harmful bacteria and promoting beneficial ones. Intestinal and plasma metabolomes were also altered. The bile acid secretion, α-linolenic acid, apoptotic, and prostate cancer pathways responded to the positive dietary butyrate-induced metabolic changes in the weanling rabbits, resulting in the inhibition of inflammation, improved antioxidant capacity, increased rates of cell proliferation and survival, and decreased levels of apoptosis. Additionally, dietary butyrate suppressed the release of pro-inflammatory factors and enhanced positive appetite regulation, which increased the average daily gain of the rabbits. These results demonstrated that dietary butyrate can help maintain the integrity of the intestinal epithelial barrier, improve the structural composition of the intestinal microflora, enhance organismal metabolism, inhibit inflammation, reduce post-weaning anorexia, and promote growth and development in early-weaning rabbits. These positive effects of dietary butyrate were exerted via the modulation of the microbe-gut-brain axis.

The Updated Review on Plant Peptides and Their Applications in Human Health

Biologically active plant peptides, consisting of secondary metabolites, are compounds (amino acids) utilized by plants in their defense arsenal. Enzymatic processes and metabolic pathways secrete these plant peptides. They are also known for their medicinal value and have been incorporated in therapeutics of major human diseases. Nevertheless, its limitations (low bioavailability, high cytotoxicity, poor absorption, low abundance, improper metabolism, etc.) have demanded a need to explore further and discover other new plant compounds that overcome these limitations. Keeping this in mind, therapeutic plant proteins can be excellent remedial substitutes for bodily affliction. A multitude of these peptides demonstrates anti-carcinogenic, anti-microbial, anti-HIV, and neuro-regulating properties. This article's main aim is to list out and report the status of various therapeutic plant peptides and their prospective status as peptide-based drugs for multiple diseases (infectious and non-infectious). The feasibility of these compounds in the imminent future has also been discussed.

Therapeutic Potential of Medicinal Plant Proteins: Present Status and Future Perspectives

Biologically active molecules obtained from plant sources, mostly including secondary metabolites, have been considered to be of immense value with respect to the treatment of various human diseases. However, some inevitable limitations associated with these secondary metabolites like high cytotoxicity, low bioavailability, poor absorption, low abundance, improper metabolism, etc., have forced the scientific community to explore medicinal plants for alternate biologically active molecules. In this context, therapeutically active proteins/peptides from medicinal plants have been promoted as a promising therapeutic intervention for various human diseases. A large number of proteins isolated from the medicinal plants have been shown to exhibit anti-microbial, anti-oxidant, anti-HIV, anticancerous, ribosome-inactivating and neuro-modulatory activities. Moreover, with advanced technological developments in the medicinal plant research, medicinal plant proteins such as Bowman-Birk protease inhibitor and Mistletoe Lectin-I are presently under clinical trials against prostate cancer, oral carcinomas and malignant melanoma. Despite these developments and proteins being potential drug candidates, to date, not a single systematic review article has documented the therapeutical potential of the available biologically active medicinal plant proteome. The present article was therefore designed to describe the current status of the therapeutically active medicinal plant proteins/peptides vis-à-vis their potential as future protein-based drugs for various human diseases. Future insights in this direction have also been highlighted.

Antifungal Proteins with Antiproliferative Activity on Cancer Cells and HIV-1 Enzyme Inhibitory Activity from Medicinal Plants and Medicinal Fungi

A variety of fungi, plants, and their different tissues are used in Traditional Chinese Medicine to improve health, and some of them are recommended for dietary therapy. Many of these plants and fungi contain antifungal proteins and peptides which suppress spore germination and hyphal growth in phytopathogenic fungi. The aim of this article is to review antifungal proteins produced by medicinal plants and fungi used in Chinese medicine which also possess anticancer and human immunodeficiency virus-1 (HIV-1) enzyme inhibitory activities.

Bioactive Proteins in Panax notoginseng Roots and Other Panax Species

The genus Panax consists of a group of prized medicinal herbs. Major members of the Panax genus include P. ginseng, P. notoginseng, P. quinquefolius, and P. vietnamensis. They possess various bioactive constituents such as ginsenosides, saponins, polysaccharides and proteins. Many of them were reported to show beneficial effects on human health. Ginsenosides and saponins of ginsengs caught the sight of most researchers. Precise investigations revealed their roles on improvement of the functioning of the nervous system, cardiovascular system, and other functions. In contrast, our knowledge of the bioactive Panax proteins is relatively limited. A number of proteins from P. ginseng, the most valuable member of Panax species, have been investigated and proved to be beneficial to our body. Meanwhile, a few bioactive P. notoginseng proteins, such as ribonucleases and antifungal proteins, have been characterized and reported. We summarize herein the proteins present in P. notoginseng that have been identified, and try to compare them with those from other Panax species with a similar structure or bioactivity, and conclude whether the proteins in P. notoginseng have any distinctive features.

Characterization of chickpea (Cicer arietinum L.) lectin for biological activity

Lectins are proteins that are subject of intense investigations. Information on lectin from chickpea (Cicer arietinum L.) with respect to its biological activities are very limited. In this study, we purified lectin from the seeds of chickpea employing DEAE-cellulose and SP-Sephadex ion exchange chromatography and identified its molecular subunit mass as 35 kDa. The free radical scavenging activity of lectin measured by the DPPH assay has IC₅₀ of 0.88 µg/mL. Lectin exerted antifungal activity against Candida krusei, Fusarium oxysporium oxysporium, Saccharomyces cerevisiae and Candida albicans, while antibacterial activity against E. coli, B. subtilis, S. marcescens and P. aeruginosa. The minimum inhibitory concentrations were 200, 240, 160 and 140 µg for C. krusei, F. oxysporium, S. cerevisiae and C. albicans respectively. Lectin was further examined for its antiproliferative potential against cancerous cell line. The cell viability assay indicated a high inhibition activity on Ishikawa, HepG2, MCF-7 and MDA-MB-231 with IC₅₀ value of 46.67, 44.20, 53.58 and 37.46 µg/mL respectively. These results can provide a background for future research into the benefits of chickpea lectin to pharmacological perspective.

Dolichos lablab Protects Against Nonalcoholic Fatty Liver Disease in Mice Fed High-Fat Diets

Hyacinth bean, Dolichos lablab or Lablab purpureus, has been used for centuries in India and China as an edible pod and animal forage, as well as to treat diarrhea and other gastrointestinal disease in traditional Korean medicine. Recently, we have demonstrated that D. lablab extract (DLL-Ex) prevented free fatty acid-induced lipid accumulation in an in vitro cellular nonalcoholic fatty liver disease (NAFLD) model. In this study, we, thus, aimed at clarifying the hepatoprotective effects of DLL-Ex in a high-fat diet-induced in vivo animal NAFLD model, as well as at elucidating underlying mechanisms of identified effects. Sixty, 6-week-old, male C57BL/6J mice were randomly divided into six groups: a control group fed a low-fat diet, four high-fat diet (HFD) groups, three receiving daily oral supplementation of DLL-Ex (25, 50, and 100 mg/kg/day), and one HFD group receiving daily oral supplementation of MILK (100 mg/kg/day). Effects of DLL-Ex supplementation were evaluated by histopathological and histochemical assessments. DLL-Ex supplementation inhibited HFD-induced increases in body weight and body fat mass and ameliorated increases in body weight, manifested as decreased liver function tests, lower serum triglycerides and cholesterol levels, and increased serum adiponectin levels. The expression of hepatic genes involved in lipid droplet accumulation and in fatty acid uptake was also decreased. We provide evidence of a protective effect of DLL-Ex against HFD-induced fatty liver disease in an animal model.

Purification and characterization of a novel chitinase from Trichosanthes dioica seed with antifungal activity

Chitinases are a group of enzymes that show differences in their molecular structure, substrate specificity, and catalytic mechanism and widely found in organisms like bacteria, yeasts, fungi, arthropods actinomycetes, plants and humans. A novel chitinase enzyme (designated as TDSC) was purified from Trichosanthes dioica seed with a molecular mass of 39±1 kDa in the presence and absence of β-mercaptoethanol. The enzyme was a glycoprotein in nature containing 8% neutral sugar. The N-terminal sequence was determined to be EINGGGA which did not match with other proteins. Amino acid analysis performed by LC-MS revealed that the protein was rich in leucine. The enzyme was stable at a wide range of pH (5.0-11.0) and temperature (30-90 °C). Chitinase activity was little bit inhibited in the presence of chelating agent EDTA (ethylenediaminetetraaceticacid), urea and Ca(2+). A strong fluorescence quenching effect was found when dithiothreitol and sodium dodecyl sulfate were added to the enzyme. TDSC showed antifungal activity against Aspergillus niger and Trichoderma sp. as tested by MTT assay and disc diffusion method.

Isolation of a Hemagglutinin with Potent Antiproliferative Activity and a Large Antifungal Defensin from Phaseolus vulgaris cv. Hokkaido Large Pinto Beans

Lectins (hemagglutinins) are defined as sugar-binding proteins or glycoproteins with various biological activities. A 60 kDa dimeric hemagglutinin with a blocked N-terminus was isolated in large yield (190 mg/60 g) from the common edible bean Phaseolus vulgaris cv. Hokkaido large pinto bean. Its hemagglutinating, antifungal, and antitumor activities as well as the effects of carbohydrate and metal ions on its hemagglutinating activity were examined. It inhibited the proliferation of nasopharyngeal carcinoma (CNE2), human breast cancer (MCF7), and hepatoma (HepG2) cells. The IC50 values toward HepG2, MCF7, and CNE2 cells after treatment for 48 h were 8.1, 6.07, and 7.49 μM, respectively, which were relatively low among lectins of different P. vulgaris cultivars. From the pinto beans, a 10888 Da antifungal peptide with similarity to plant defensins as revealed by mass spectroscopic analysis was also isolated with a yield of 3.2 mg of proteins from 60 g of beans. The large defensin was capable of inhibiting mycelial growth in Mycosphaerella arachidicola, Setosphaeria turcica, Bipolaris maydis, and Fusarium oxysporum but not in Valsa mali.

Plant antifungal proteins and their applications in agriculture

Fungi are far more complex organisms than viruses or bacteria and can develop numerous diseases in plants that cause loss of a substantial portion of the crop every year. Plants have developed various mechanisms to defend themselves against these fungi which include the production of low-molecular-weight secondary metabolites and proteins and peptides with antifungal activity. In this review, families of plant antifungal proteins (AFPs) including defensins, lectins, and several others will be summarized. Moreover, the application of AFPs in agriculture will also be analyzed.

Structural and functional evolution of chitinase-like proteins from plants

The plant genome contains a large number of sequences that encode catalytically inactive chitinases referred to as chitinase-like proteins (CLPs). Although CLPs share high sequence and structural homology with chitinases of glycosyl hydrolase 18 (TIM barrel domain) and 19 families, they may lack the binding/catalytic activity. Molecular genetic analysis revealed that gene duplication events followed by mutation in the existing chitinase gene have resulted in the loss of activity. The evidences show that adaptive functional diversification of the CLPs has been achieved through alterations in the flexible regions than in the rigid structural elements. The CLPs plays an important role in the defense response against pathogenic attack, biotic and abiotic stress. They are also involved in the growth and developmental processes of plants. Since the physiological roles of CLPs are similar to chitinase, such mutations have led to plurifunctional enzymes. The biochemical and structural characterization of the CLPs is essential for understanding their roles and to develop potential utility in biotechnological industries. This review sheds light on the structure-function evolution of CLPs from chitinases.

Effects of processing conditions on the stability of polyphenolic contents and antioxidant capacity of Dolichos lablab L

The effects of raw, dry heated and pressure cooked samples on total phenolic components and antioxidant activity in commonly consumed field bean, Dolichos lablab L. was investigated. The raw and processed samples were extracted with 70% methanol. Processing of legumes caused decreases in total phenolic content when compared to the raw samples. However, the dry heating caused remarkable increase in tannin contents (1.809 ± 0.25 g GAE/100 g extract). Dry heated samples of D. lablab was found to possess the highest DPPH (IC50, 2.53 ± 0.17 μg/ml), TEAC (4649.8 ± 38.4 μmol/g DM), OH˙ radical (IC50, 42.2 ± 0.67 μg/ml) scavenging activities, inhibition of linoleic acid and ferric reducing capacity than other samples. The raw samples displayed the highest antihemolytic activity (59.6 ± 1.53%) and chelating capacity (74.2 ± 1.37 mg EDTA/g). Dry heat processing exhibited several advantages in retaining the antioxidant components and activities. The higher correlation was found the phenolic content with chelating (r (2)  = 0.933) and antihemolytic (r (2)  = 0.839) activities, but a poor correlation with other assays. Moreover, the content of tannins gave good correlation (r (2)  = 0.644-0.997) with all antioxidant assays. The low correlation values between total phenols and the antioxidative activity suggest that the major antioxidant compounds in studied seeds might be tannins.

A peptide with potent antifungal and antiproliferative activities from Nepalese large red beans

An antifungal defensin-like peptide with a molecular mass of 7.1kDa was isolated from dried Nepalese large red beans (Phaseolus angularis). The purification protocol employed included ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on SP-Sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. The antifungal peptide was unadsorbed on DEAE-cellulose, and adsorbed on Affi-gel blue gel and SP-Sepharose. The antifungal peptide inhibited mycelial growth in Fusarium oxysporum and Mycosphaerella arachidicola with an IC(50) value of 1.4 and 1.8 microM, respectively. It did not inhibit HIV-1 reverse transcriptase when tested up to 200 microM. It exerted an antiproliferative action on L1210 leukemia cells and MBL2 lymphoma cells with an IC(50) of 15 and 60 microM, respectively.

A protein with antiproliferative, antifungal and HIV-1 reverse transcriptase inhibitory activities from caper (Capparis spinosa) seeds

A protein exhibiting an N-terminal amino acid sequence with some similarity to imidazoleglycerol phosphate synthase was purified from fresh Capparis spinosa melon seeds. The purification protocol entailed anion exchange chromatography on DEAE-cellulose, cation exchange chromatography on SP-Sepharose, and finally gel filtration by fast protein liquid chromatography on Superdex 75. The protein was adsorbed using 20 mM Tris-HCl buffer (pH 7.4) and desorbed using 1 M NaCl in the starting buffer from the DEAE-cellulose column and SP-Sepharose column. The protein demonstrated a molecular mass of 38 kDa in gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that it was monomeric. The protein inhibited proliferation of hepatoma HepG2 cells, colon cancer HT29 cells and breast cancer MCF-7 cells with an IC(50) of about 1, 40 and 60 microM, respectively. It inhibited HIV-1 reverse transcriptase with IC(50) of 0.23 microM. It inhibited mycelial growth in the fungus, Valsa mali. It did not exhibit hemagglutinating, ribonuclease, mitogenic or protease inhibitory activities.

Isolation and biochemical characterization of a novel leguminous defense peptide with antifungal and antiproliferative potency

Leguminous plants have formed a popular subject of research owing to the abundance of proteins and peptides with important biological activities that they produce. The antifungal proteins and peptides have been purified from a number of leguminous species. However, research continues to discover novel antifungal plant-produced peptides and proteins are being needed, specially those novel ones with both antifungal activity and other significant bioactivities. The objective of this study was to isolate a novel peptide from Phaseolus limensis. A 6.8 kDa peptide designated Limyin, with both antifungal and antiproliferative activity, was isolated from the large lima bean (P. limensis) legumes. The isolation procedure consisted of extraction, precipitation, affinity chromatography on Affi-gel blue gel, ion chromatography on SP-Toyopearl, and gel filtration on Superdex 75. Its N-terminal sequence was determined to be KTCENLATYYRGPCF, showing high homology to defensin and defensin precursors from plants. It potently suppressed mycelial growth in Alternaria alternata, Fusarium solani, and Botrytis cinerea. Its antifungal activity was stable up to 80 degrees C. It showed antiproliferative activity towards tumor cells including human liver hepatoma cells Bel-7402 and neuroblastoma cells SHSY5Y. However, it had no effect on bacteria Staphylococcus aureus and Salmonella. The present findings make a significant addition of the research on leguminous plants.

Abundant class III acidic chitinase homologue in tamarind (Tamarindus indica) seed serves as the major storage protein

The phyla Leguminosae contains protease inhibitors, lectins, chitinases, and glycohydrolases as major defense proteins in their seeds. Electrophoretic analysis of the seed proteins of tamarind ( Tamarindus indica L.), an agri-waste material, indicated the unusual presence of two major proteins comparable to overexpression of recombinant proteins. These proteins were identified by amino-terminal analysis to be (1) Kunitz-type trypsin inhibitor and (2) class III endochitinase (34000 Da). These two proteins were purified to apparent homogeneity by a single-step chitin bead affinity chromatography and characterized. The Kunitz inhibitor was specific toward inhibiting trypsin with a stoichiometry of 1:1. The 33000 +/- 1000 Da protein, accounting for >50% of the total seed protein, is an acidic glycoprotein exhibiting a very low endotype hydrolytic activity toward chitin derivatives. SDS-PAGE followed by densitometry of tamarind seed germination indicates the disappearance of the chitinase with the concomitant appearance of a cysteine endopeptidase. On the basis of its abundance, accumulation without any pathogenesis-related stimulus, temporal regulation, amino acid composition, and very low enzyme activity, this 34000 Da protein designated "tamarinin" physiologically serves as the major storage protein.

Peptides derived from dolicholin, a phaseolin-like protein in country beans (Dolichos lablab), potently stimulate cholecystokinin secretion from enteroendocrine STC-1 cells

Peptides derived from soybean beta-conglycinin and pork protein stimulate cholecystokinin (CCK) secretion from the enteroendocrine cells (EECs) and suppress food intake. Here we examined CCK-releasing activities from the enteroendocrine cell line STC-1, in peptides derived from underutilized legumes, and found much higher activity in the peptic hydrolysate of Country beans (CBP) compared to that from other legume-derived peptides including beta-conglycinin peptone. Active components in CBP were separated into acetonitrile-soluble fractions, but the activities were abolished after pronase treatment. To identify the Country bean protein containing the active peptides, Country bean protein extracts in an alkaline solution (CBE) were fractionated based on isoelectric point or molecular weight. Peptones prepared from CBE fractions containing a 51 kDa major protein stimulated CCK release, but other fractions did not. N-Terminal sequence analysis indicated that the 51 kDa protein is a phaseolin-like globular protein, and we designated this protein dolicholin. These results indicate that Country bean-derived peptides are very potent legume peptides in stimulating CCK secretion from EECs and that the stimulant peptides originate from dolicholin, a newly identified phaseolin-like globular protein in Country beans.

The role of plant defence proteins in fungal pathogenesis

SUMMARY It is becoming increasingly evident that a plant-pathogen interaction may be compared to an open warfare, whose major weapons are proteins synthesized by both organisms. These weapons were gradually developed in what must have been a multimillion-year evolutionary game of ping-pong. The outcome of each battle results in the establishment of resistance or pathogenesis. The plethora of resistance mechanisms exhibited by plants may be grouped into constitutive and inducible, and range from morphological to structural and chemical defences. Most of these mechanisms are defensive, exhibiting a passive role, but some are highly active against pathogens, using as major targets the fungal cell wall, the plasma membrane or intracellular targets. A considerable overlap exists between pathogenesis-related (PR) proteins and antifungal proteins. However, many of the now considered 17 families of PR proteins do not present any known role as antipathogen activity, whereas among the 13 classes of antifungal proteins, most are not PR proteins. Discovery of novel antifungal proteins and peptides continues at a rapid pace. In their long coevolution with plants, phytopathogens have evolved ways to avoid or circumvent the plant defence weaponry. These include protection of fungal structures from plant defence reactions, inhibition of elicitor-induced plant defence responses and suppression of plant defences. A detailed understanding of the molecular events that take place during a plant-pathogen interaction is an essential goal for disease control in the future.

A thaumatin-like antifungal protein from the emperor banana

A 20-kDa protein with substantial N-terminal sequence homology to thaumatin-like proteins was isolated from ripe fruits of the emperor banana, Musa basjoo cv. 'emperor banana'. The isolation procedure entailed (NH(4))(2)SO(4) precipitation, ion exchange chromatography on DEAE-cellulose, and affinity chromatography on Affi-gel blue gel. The thaumatin-like protein inhibited mycelial growth in Fusarium oxysporum and Mycosphaerella arachidicola. However, it did not affect the mitogenic response of murine splenocytes or [methyl-(3)H] thymidine incorporation by tumor cells. The activity of HIV-1 reverse transcriptase was slightly inhibited.

Conifer defense against insects: proteome analysis of Sitka spruce (Picea sitchensis) bark induced by mechanical wounding or feeding by white pine weevils (Pissodes strobi)

Feeding insects can have major ecological and economic impacts on both natural and planted forests. Understanding the molecular and biochemical mechanisms by which conifers defend themselves from insect pests is a major goal of ongoing research in forest health genomics. In previous work, we demonstrated a complex system of anatomical, chemical, and transcriptome responses in Sitka spruce (Picea sitchensis) upon feeding by the economically significant insect pest, the white pine weevil (Pissodes strobi). In this study, changes to the proteome of Sitka spruce bark tissue were examined subsequent to feeding by white pine weevils or mechanical wounding. 2-D PAGE and high-throughput MS/MS were used to examine induced changes in protein abundance and protein modification. Significant changes were observed as early as 2 h following the onset of insect feeding. Among the insect-induced proteins are a series of related small heat shock proteins, other stress response proteins, proteins involved in secondary metabolism, oxidoreductases, and a novel spruce protein. Comparison of protein expression and cDNA microarray profiles of induced spruce stem tissues reveals the complementary nature of transcriptome and proteome analyses and the need to apply a multifaceted approach to the large-scale analysis of plant defense systems.

Bacisubin, an antifungal protein with ribonuclease and hemagglutinating activities from Bacillus subtilis strain B-916

An antifungal protein, with a molecular mass of 41.9 kDa, and designated as bacisubin, was isolated from a culture of Bacillus subtilis strain B-916. The isolation procedure consisted of ion exchange chromatography on DEAE-Sepharose Fast Flow, and fast protein liquid chromatography on Phenyl Sepharose 6 Fast Flow and hydroxyapatite columns. The protein was adsorbed on all three chromatographic media. Bacisubin exhibited inhibitory activity on mycelial growth in Magnaporthe grisease, Sclerotinia sclerotiorum, Rhizoctonia solani, Alternaria oleracea, A. brassicae and Botrytis cinerea. The IC50 values of its antifungal activity toward the last four fungal species were 4.01 microM, 0.087 microM, 0.055 microM and 2.74 microM, respectively. Bacisubin demonstrated neither protease activity, nor protease inhibitory activity. However, it manifested ribonuclease and hemagglutinating activities.

An antifungal peptide from red lentil seeds

An antifungal peptide, with a molecular mass of 11 kDa, was isolated from dry seeds of the red lentil (Lens culinaris) using a procedure that involved four chromatographic steps. The antifungal peptide was unadsorbed on DEAE-cellulose, and adsorbed on Affi-gel blue gel and S-Sepharose. The final chromatographic step involved gel filtration by fast protein liquid chromatography on Superdex 75. The antifungal peptide inhibited mycelial growth in Mycosphaerella arachidicola with an IC50 of 36 microM. It also exhibited antifungal activity against Fusarium oxysporum, but there was no inhibitory activity toward tumor cell lines and human immunodeficiency virus type 1 reverse transcriptase (RT).

An antifungal peptide from baby lima bean

A 6-kDa antifungal peptide with inhibitory activity on mycelial growth in Fusarium oxysporum, Mycosphaerella arachidicola, and Physalospora piricola was isolated from baby lima beans. The peptide suppressed growth in M. arachidicola with an IC(50) of 0.87 muM and inhibited activity of HIV-1 reverse transcriptase with an IC(50) of 4 muM. The peptide exhibited an N-terminal amino acid sequence similar to those of leguminous defensins. The isolation procedure comprised ion exchange chromatography on diethylaminoethyl (DEAE)-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on carboxymethyl (CM)-cellulose, and gel filtration by fast protein liquid chromatography on Superdex 75. The peptide was unadsorbed on DEAE-cellulose and Affi-gel blue gel but was adsorbed on CM-cellulose.

An antifungal protein from the pea Pisum sativum var. arvense Poir

An antifungal protein with a molecular mass of 11 kDa and a lysine-rich N-terminal sequence was isolated from the seeds of the pea Pisum sativum var. arvense Poir. The antifungal protein was unadsorbed on DEAE-cellulose but adsorbed on Affi-gel blue gel and CM-cellulose. It exerted antifungal activity against Physalospora piricola with an IC50 of 0.62 microM, and also antifungal activity against Fusarium oxysporum and Mycosphaerella arachidicola. It inhibited human immunodeficiency virus type 1 reverse transcriptase with an IC50 of 4.7 microM.

Isolation and characterization of a 30 kD antifungal protein from seeds of Sorghum bicolor

An antifungal protein of about 30,000 Da was isolated from seeds of Sorghum bicolor L. using chromatographic techniques, including gel filtration, ion exchange, and high-performance liquid chromatography in a reverse-phase column. This protein (termed 30 kD protein) showed a minimal inhibitory concentration of 36 microg/ml for Candida parapsilosis and C. tropicalis, and 18 microg/ml for C. albicans. The 30 kD protein inhibited adherence to the cover glass and formation of a germinative tube of C. albicans at concentrations over 300 and 150 microg/ml, respectively. Transmission electron microscopy of yeast forms of C. albicans after incubation with 18 mug/ml of the 30 kD protein for 24 h revealed marked ultrastructural changes in the fungus. No toxicity of the 30 kD protein to the culture of Hep2 cells at concentrations equal to or less than 1,000 microg/ml was observed.

A novel ribonuclease from fresh fruiting bodies of the portabella mushroom Agaricus bisporus

A 14 kDa ribonuclease with a novel N-terminal sequence was isolated from fresh fruiting bodies of the portabella mushroom. It was adsorbed on DEAE-cellulose and carboxymethyl-cellulose, and demonstrated the highest ribonucleolytic potency toward poly (A), 60% as much activity toward poly (C), 40% as much activity toward poly (U), and the least activity (7% as much) toward poly (G). It exhibited a pH optimum at pH 4.5 and a temperature optimum at 60 °C. Its activity at 100 °C was higher than that at 20 °C.Key words: ribonuclease, portabella mushroom, isolation.

A ribonuclease from the wild mushroom Boletus griseus

A ribonuclease (RNase) with a molecular mass of 29 kDa and cospecific for poly A and poly U was isolated from fruiting bodies of the mushroom Boletus griseus. Its N-terminal sequence exhibited some similarity to those of RNases from the mushrooms Irpex lacteus and Lentinus edodes. The RNase was adsorbed on diethylaminoethyl-cellulose, Q-Sepharose, and Affi-gel blue gel and was unadsorbed on CM-cellulose. The enzyme exhibited a temperature optimum between 60 and 70 degrees C and a pH optimum at 3.5.

Limenin, a defensin-like peptide with multiple exploitable activities from shelf beans

From the seeds of the shelf bean, an antifungal peptide with a molecular mass of 6.5 kDa was isolated. The isolation procedure comprised affinity chromatography on Affi-gel blue gel, ion exchange chromatography on Mono S, and gel filtration on Superdex 75. The peptide was adsorbed on Affi-gel blue gel and Mono S. It potently suppressed mycelial growth in Botrytis cinerea, Fusarium oxysporum, and Mycosphaerella arachidicola with an IC(50) of 2.9, 2.1, and 0.34 microM, respectively. It exerted antibacterial activity toward several bacterial species with an IC(50) approximating 100 microM. [Methyl-(3)H]-thymidine incorporation into isolated mouse splenocytes was stimulated. [Methyl-(3)H]-thymidine incorporation into M1 (myeloma) and L1210 (leukemia) cells was inhibited. The peptide reduced the activity of HIV-1 reverse transcriptase and also inhibited translation in a cell-free rabbit reticulocyte lysate system.

An antifungal protein from flageolet beans

A protein with antifungal and hemagglutinating activities was isolated from dried flageolet beans (Phaseolus vulgaris cv. 'Flageolet Bean'). The protein was unadsorbed on DEAE-cellulose but adsorbed on Affi-gel blue gel and CM-cellulose. The protein demonstrated antifungal activity against Mycophaerella arachidicola with an IC50 of 9.8 microM, but was inactive toward Fusarium oxysporum and Botrytis cinerea. Its hemagglutinating activity could not be inhibited by a variety of the sugars tested. The activity was stable up to 60 degrees C. At 70 degrees C, 75% of the hemagglutinating activity remained while no activity was discernible at and above 100 degrees C. The hemagglutinating activity was stable in the presence of a variety of monovalent, divalent and trivalent chlorides, and also when the ambient pH changed from 3 to 12. It did not exert any mitogenic activity on mouse splenocytes in vitro. Neither did it inhibit HIV-1 reverse transcriptase. It inhibited [3H-methyl]-thymidine incorporation into leukemia L1210 cells with an IC50 of about 4 microM.

An antifungal peptide from the coconut

A chromatographic procedure consisting of ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-cellulose, and gel filtration by fast performance liquid chromatography on Supedex 75 was utilized to isolate a 10 kDa antifungal peptide from coconut flesh. The peptide was unadsorbed on DEAE-cellulose, but adsorbed on Affi-gel blue gel and CM-cellulose. It displayed antifungal activity against Fusarium oxysporum, Mycosphaerella arachidicola and Physalospora piricola. The IC50 values of its inhibitory activities on mycelial growth in M. arachidicola and HIV-1 reverse transcriptase activity were respectively 1.2 and 52.5 microM.

Lunatusin, a trypsin-stable antimicrobial peptide from lima beans (Phaseolus lunatus L.)

An anti-fungal peptide designated as lunatusin, with a molecular mass around 7kDa, was purified from the seeds of Chinese lima bean (Phaseolus lunatus L.). The peptide was isolated using a simple protocol consisting of affinity chromatography on Affi-gel blue gel and gel filtration on Superdex 75. Lunatusin exerted an anti-fungal activity toward fungal species such as Fusarium oxysporum, Mycosphaerella arachidicola and Botrytis cinerea, and an antibacterial action on, Bacillus megaterium, Bacillus subtilis, Proteus vulgaris and Mycobacterium phlei. It also inhibited proliferation in the breast cancer cell line MCF-7. Lunatusin reduced the activity of HIV-1 reverse transcriptase and it also inhibited translation in a cell-free rabbit reticulocyte lysate system. Its anti-fungal activity was retained after incubation with trypsin. Lunatusin elicited a mitogenic response from mouse splenocytes.

An antifungal protein from ginger rhizomes

There are very few reports on antifungal proteins from rhizomes and there is none from the family of Zingiberaceae. An antifungal protein with a novel N-terminal sequence was isolated from ginger rhizomes utilizing a protocol that involved ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, and fast protein liquid chromatography on Superdex 75. The protein was unadsorbed on DEAE-cellulose and adsorbed on Affi-gel blue gel. It exhibited an apparent molecular mass of 32kDa and exerted antifungal activity toward various fungi including Botrytis cinerea, Fusarium oxysporum, Mycosphaerella arachidicola, and Physalospora piricola.

A chitinase with antifungal activity from the mung bean

A chitinase with antifungal activity was isolated from mung bean (Phaseolus mungo) seeds. The procedure entailed aqueous extraction, (NH4)2SO4 precipitation, ion-exchange chromatography on CM-Sepharose, high-performance liquid chromatography (HPLC) on Poros HS-20, and gel filtration on Sephadex G-75. The protein exhibited a molecular mass of 30.8 kDa in SDS-polyacrylamide gel electrophoresis. Its pI was 6.3 as determined by isoelectric focusing. The specific activity of the chitinase was estimated to be 3.81 U/mg. The enzyme expressed its optimum activity at pH 5.4 and was stable from 40 to 50 degrees C. It exerted antifungal action toward Fusarium solani, Fusarium oxysporum, Mycosphaerella arachidicola, Pythium aphanidermatum, and Sclerotium rolfsii.

Phaseococcin, an antifungal protein with antiproliferative and anti-HIV-1 reverse transcriptase activities from small scarlet runner beans

From the seeds of small scarlet runner beans (Phaseolus coccineus 'Minor'), an antifungal protein with an N-terminal sequence homologous to those of defensins was isolated. The antifungal protein bound to Affi-gel blue gel and Mono S but it did not bind to DEAE-cellulose. It was further purified by gel filtration on a Superdex peptide column. It exhibited a molecular mass of 5422 Da as determined by mass spectrometry. The protein, designated as phaseococcin, suppressed mycelial growth in a number of fungi including Botrytis cinerea, Coprinus comatus, Fusarium oxysporum, Mycosphaerella arachidicola, Physalospora piricola, and Rhizoctonia solani. It also inhibited proliferation in several Bacillus species and the leukemia cell lines HL60 and L1210 and curtailed the activity of HIV-1 reverse transcriptase. It did not affect proliferation of mouse splenocytes and neither did it inhibit protein synthesis in a cell-free rabbit reticulocyte lysate system.Key words: antifungal proteins, runner beans, antiproliferative.

Isolation of trichogin, an antifungal protein from fresh fruiting bodies of the edible mushroom Tricholoma giganteum

An antifungal protein was isolated from the mushroom Tricholoma giganteum var. golden blessings. The protocol included ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-cellulose, and gel filtration by fast protein liquid chromatography on Superdex 75. The antifungal protein, designated trichogin, was unadsorbed on DEAE-cellulose but was adsorbed on Affi-gel blue gel and CM-cellulose. It exhibited antifungal activity against Fusarium oxysporum, Mycosphaerella arachidicola and Physalospora piricola. Trichogin inhibited HIV-1 reverse transcriptase with an IC50 of 83 nM.

Vulgarinin, a broad-spectrum antifungal peptide from haricot beans (Phaseolus vulgaris)

From the seeds of haricot beans (Phaseolus vulgaris), an antifungal peptide with a molecular mass around 7 kDa was purified by using a simple protocol consisting of affinity chromatography on Affi-gel blue gel and gel filtration on Superdex 75. This peptide named vulgarinin manifested an antifungal activity toward fungal species such as Fusarium oxysporum, Mycosphaerella arachidicola, Physalospora piricola and Botrytis cinerea, and an antibacterial action on Mycobacterium phlei, Bacillus megaterium, Bacillus subtilis and Proteus vulgaris. It also inhibited proliferation in leukemia cell lines L1210 and M1 and breast cancer cell line MCF-7. This peptide could reduce the activity of HIV-1 reverse transcriptase and inhibited translation in a cell-free rabbit reticulocyte lysate system. Its antifungal activity was retained after incubation with trypsin.

Agrocybin, an antifungal peptide from the edible mushroom Agrocybe cylindracea

An antifungal peptide with a molecular mass of 9 kDa was isolated from fresh fruiting bodies of the mushroom Agrocybe cylindracea. The isolation procedure comprised ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography by fast protein liquid chromatography (FPLC) on Mono S, and FPLC-gel filtration on a Superdex 75 column. The antifungal peptide, designated as agrocybin, was unadsorbed on DEAE-cellulose, and adsorbed on Affi-gel blue gel and Mono S. Agrocybin exerted antifungal activity against several fungal species but lacked inhibitory activity against bacteria when tested up to 300 microM. The activity of HIV-1 reverse transcriptase was attenuated in the presence of agrocybin. It exhibited weaker mitogenic activity than Con A on isolated murine splenocytes, but was devoid of antiproliferative activity on Hep G2 (hepatoma) cells when tested at 110 microM.

Isolation of alliumin, a novel protein with antimicrobial and antiproliferative activities from multiple-cloved garlic bulbs

A protein designated alliumin, with a molecular mass of 13 kDa and an N-terminal sequence similar to a partial sequence of glucanase, and demonstrating antifungal activity against Mycosphaerella arachidicola, but not against Fusarium oxysporum, was isolated from multiple-cloved garlic (Allium sativum) bulbs. The protein, designated as alliumin, was purified using ion exchange chromatography on DEAE-cellulose, CM-cellulose and Mono S, affinity chromatography on Affi-gel blue gel, and gel filtration on Superdex 75. Alliumin was unadsorbed on DEAE-cellulose, but was adsorbed on Affi-gel blue gel, CM-cellulose and Mono S. Its antifungal activity was retained after boiling for 1 h and also after treatment with trypsin or chymotrypsin (1:1, w/w) for 30 min at room temperature. Alliumin was inhibitory to the bacterium Pseudomonas fluorescens and exerted antiproliferative activity toward leukemia L1210 cells. However, it was devoid of ribonuclease activity, protease activity, mitogenic activity toward mouse splenocytes, and antiproliferative activity toward hepatoma Hep G2 cells.

Purification and characterization of a chitinase-like antifungal protein from black turtle bean with stimulatory effect on nitric oxide production by macrophages

An antifungal protein was isolated from black turtle bean, Phaseolus vulgaris cv. "Black Turtle". The purified protein displayed an N-terminal amino acid sequence with 60-80% homology to chitinases. The isolated protein specifically inhibited two species of fungi, namely Fusarium oxysporum and Mycosphaerella arachidicola , among several phytopathogenic fungi tested. Its antifungal activity was retained after incubation at 60 degrees C for 15 minutes, diminished after exposure to 80 degrees C, and was completely abrogated after treatment at 100 degrees C. The antifungal protein had higher thermostability than the antifungal protein mollisin from chestnut. It stimulated nitric oxide production by murine peritoneal macrophages, but exerted neither mitogenic nor cytotoxic activity on murine splenocytes, activities that may be related to allergic responses.

Coccinin, an antifungal peptide with antiproliferative and HIV-1 reverse transcriptase inhibitory activities from large scarlet runner beans

An antifungal peptide, designated coccinin, with a molecular mass of 7kDa and an N-terminal sequence resembling those of defensins, was purified from the seeds of large scarlet runner beans (Phaseolus coccineus cv. 'Major'). The peptide isolated was unadsorbed on DEAE-cellulose, and adsorbed on Affi-gel blue gel and Mono S. The peptide excerted antifungal activity on a number of fungal species including Botrytis cinerea, Coprinus comatus, Fusarium oxysporum, Mycosphaerella arachidicola, Physalospora piricola, and Rhizoctonia solani. It also inhibited proliferation in the leukemia cell lines HL60 and L1210, and reduced the activity of HIV-1 reverse transcriptase. However, it did not affect proliferation of mouse splenocytes.

Antifungal peptides, a heat shock protein-like peptide, and a serine-threonine kinase-like protein from Ceylon spinach seeds

Two antifungal peptides (designated alpha- and beta-basrubrins) with molecular masses of 4-5 kDa and distinct N-terminal sequences, and a peptide and a protein with N-terminal sequences resembling heat shock protein (hsp) and serine-threonine kinase, respectively, were isolated from seeds of the Ceylon spinach Basella rubra. The purification procedure entailed saline extraction, (NH4)2SO4 precipitation, ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion exchange chromatography on CM-cellulose, and FPLC-gel filtration on a Superdex peptide column. alpha- and beta-basrubrins inhibited mycelial growth in Botrytis cirerea with an IC50 value of 7.5 and 14.7 microM, respectively, Mycosphaerella arachidicola with an IC50 of 12.4 and 6.9 microM, and Fusarium oxysporum with an IC50 of 5.8 and 6.2 microM. Neither alpha-basrubrin nor beta-basrubin exhibited DNase, RNase, lectin or protease activity, indicating that their antifungal action is not due to these activities. HIV-1 reverse transcriptase was inhibited by alpha- and beta-basrubrins with an IC50 of 246 and 370 microM, respectively. Translation in rabbit reticulocyte lysate was inhibited by alpha- and beta-basrubrins with an IC50 of 400 and 100 nM. The heat shock protein-like peptide and serine-threonine kinase-like protein exhibited a molecular mass of 3 and 30 kDa, respectively. They inhibited neither translation in a rabbit reticulocyte system at concentrations up to 50 microM nor HIV-1 reverse transcriptase activity at concentrations up to 400 microM. They did not exert antifungal activity toward B. cinerea, M. arachidicola, and F. oxysporum when tested up to 16 microg. None of the aforementioned proteins demonstrated DNase, RNase, protease or lectin activity.

Antifungal proteins and peptides of leguminous and non-leguminous origins

Antifungal proteins and peptides, as their names imply, serve a protective function against fungal invasion. They are produced by a multitude of organisms including leguminous flowering plants, non-leguminous flowering plants, gymnosperms, fungi, bacteria, insects and mammals. The intent of the present review is to focus on the structural and functional characteristics of leguminous, as well as non-leguminous, antifungal proteins and peptides. A spectacular diversity of amino acid sequences has been reported. Some of the antifungal proteins and peptides are classified, based on their structures and/or functions, into groups including chitinases, glucanases, thaumatin-like proteins, thionins, and cyclophilin-like proteins. Some of the well-known proteins such as lectins, ribosome inactivating proteins, ribonucleases, deoxyribonucleases, peroxidases, and protease inhibitors exhibit antifungal activity. Different antifungal proteins may demonstrate different fungal specificities. The mechanisms of antifungal action of only some antifungal proteins including thaumatin-like proteins and chitinases have been elucidated.

A napin-like polypeptide from dwarf Chinese white cabbage seeds with translation-inhibitory, trypsin-inhibitory, and antibacterial activities

Napins are 1:1 disulfide-linked complexes of a smaller (ca. 4kDa) subunit and a larger (ca. 10kDa) subunit. The intent of the present study was to ascertain the production of napin by the seeds of a Brassica species that has not been examined previously, and also to explore new biological activities of the napin. A heterodimeric 11-kDa napin-like polypeptide has been isolated from Chinese white cabbage (Brassica chinensis cv dwarf) seeds with a protocol comprising ion exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, fast protein liquid chromatography (FPLC)-ion exchange chromatography on Mono S and FPLC-gel filtration on Superdex 75. The N-terminal sequence of the 7-kDa subunit manifests striking similarity to napin large chain, albumin and trypsin inhibitor. The N-terminal sequence of the 4-kDa subunit is homologous to napin large chain and an antimicrobial peptide. The napin-like polypeptide inhibited translation in the rabbit reticulocyte system with an IC50 of 18.5nM. This translation-inhibitory activity was stable between pH 4 and 11, and between 10 and 40 degrees C. The polypeptide inhibited trypsin with a higher potency ( IC50 = 8.5 microM) than it inhibited chymotrypsin (IC50 = 220 microM), but was devoid of ribonuclease and antifungal activities. It manifested antibacterial activity against Pseudomonas aeruginosia, Bacillus subtilis, Bacillus cereus, and Bacillus megaterium. The results revealed that the napin-like polypeptide from Chinese white cabbage seeds exhibited some potentially exploitable activities.