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1.
《Plant Physiology and Biochemistry》2000,38(11):881-888
A 16-kDa protein was isolated from Helianthus annuus flowers by its ability to inhibit the germination of fungal spores. This protein, SAP16, displays an associated activity of trypsin inhibitor and was further purified to apparent homogeneity by affinity chromatography on trypsin-agarose. SAP16 causes the complete inhibition of Sclerotinia sclerotiorum ascospores germination at a concentration of 5 μg·mL–1 (0.31 μM) and a clear reduction of mycelial growth at lower concentrations, indicating a strong antifungal potency against this natural pathogen of sunflower. Our data suggest that the antifungal ability of SAP16 would not be the result of the inhibition of a fungal protease. This study contributes to the characterization of the emerging family of antifungal proteins with an associated activity of trypsin inhibition and emphasizes their role in plant resistance against fungal attack. 相似文献
2.
Glucosinolates represent a large group of plant natural products long known for diverse and fascinating physiological functions and activities. Despite the relevance and huge interest on the roles of indole glucosinolates in plant defense, little is known about their direct interaction with microbial plant pathogens. Toward this end, the metabolism of indolyl glucosinolates, their corresponding desulfo-derivatives, and derived metabolites, by three fungal species pathogenic on crucifers was investigated. While glucobrassicin, 1-methoxyglucobrassicin, 4-methoxyglucobrassicin were not metabolized by the pathogenic fungi Alternaria brassicicola, Rhizoctonia solani and Sclerotinia sclerotiorum, the corresponding desulfo-derivatives were metabolized to indolyl-3-acetonitrile, caulilexin C (1-methoxyindolyl-3-acetonitrile) and arvelexin (4-methoxyindolyl-3-acetonitrile) by R. solani and S. sclerotiorum, but not by A. brassicicola. That is, desulfo-glucosinolates were metabolized by two non-host-selective pathogens, but not by a host-selective. Indolyl-3-acetonitrile, caulilexin C and arvelexin were metabolized to the corresponding indole-3-carboxylic acids. Indolyl-3-acetonitriles displayed higher inhibitory activity than indole desulfo-glucosinolates. Indolyl-3-methanol displayed antifungal activity and was metabolized by A. brassicicola and R. solani to the less antifungal compounds indole-3-carboxaldehyde and indole-3-carboxylic acid. Diindolyl-3-methane was strongly antifungal and stable in fungal cultures, but ascorbigen was not stable in solution and displayed low antifungal activity; neither compound appeared to be metabolized by any of the three fungal species. The cell-free extracts of mycelia of A. brassicicola displayed low myrosinase activity using glucobrassicin as substrate, but myrosinase activity was not detectable in mycelia of either R. solani or S. sclerotiorum. 相似文献
3.
Inhibition of plant-pathogenic fungi by a corn trypsin inhibitor overexpressed in Escherichia coli 总被引:3,自引:0,他引:3
Chen ZY Brown RL Lax AR Cleveland TE Russin JS 《Applied and environmental microbiology》1999,65(3):1320-1324
The cDNA of a 14-kDa trypsin inhibitor (TI) from corn was subcloned into an Escherichia coli overexpression vector. The overexpressed TI was purified based on its insolubility in urea and then refolded into the active form in vitro. This recombinant TI inhibited both conidium germination and hyphal growth of all nine plant pathogenic fungi studied, including Aspergillus flavus, Aspergillus parasiticus, and Fusarium moniliforme. The calculated 50% inhibitory concentration of TI for conidium germination ranged from 70 to more than 300 microgram/ml, and that for fungal growth ranged from 33 to 124 microgram/ml depending on the fungal species. It also inhibited A. flavus and F. moniliforme simultaneously when they were tested together. The results suggest that the corn 14-kDa TI may function in host resistance against a variety of fungal pathogens of crops. 相似文献
4.
G. Chilosi C. Caruso C. Caporale L. Leonardi L. Bertini A. Buzi M. Nobile P. Magro V. Buonocore 《Journal of Phytopathology》2000,148(7-8):477-481
A trypsin inhibitor from wheat kernel (WTI) was found to have a strong antifungal activity against a number of pathogenic fungi and to inhibit fungal trypsin-like activity. WTI inhibited in vitro spore germination and hyphal growth of pathogens, with protein concentration required for 50% growth inhibition (IC50 ) values ranging from 111.7 to above 500 μg/ml. As observed by electron microscopy, WTI determined morphological alterations represented by hyphal growth inhibition and branching. One of the fungal species tested, Botrytis cinerea produced a trypsin-like protease, which was inhibited by the trypsin inhibitor. WTI, as well as other seed defence proteins, appear to be an important resistance factor in wheat kernels during rest and early germination when plants are particularly exposed to attack by potential soil-borne pathogens. 相似文献
5.
本研究旨在通过蛋白质工程手段获得结构均一性更好、活性更高、抗真菌能力更强的家蚕蛋白酶抑制剂BmSPI38的串联多聚体蛋白。利用原核表达技术获得BmSPI38串联多聚体蛋白,并通过蛋白酶抑制剂胶内活性染色、蛋白酶抑制实验和真菌生长抑制实验等探讨串联多聚体化对BmSPI38的结构均一性、抑制活性和抗真菌能力的影响。活性染色结果表明,基于多肽柔性接头的串联表达能够极大提高BmSPI38蛋白的结构均一性。蛋白酶抑制实验表明,基于接头的串联三聚体化和四聚体化能提高BmSPI38对微生物蛋白酶的抑制能力。孢子萌发实验表明,His6-SPI38L-tetramer对球孢白僵菌(Beauveria bassiana)分生孢子萌发的抑制能力显著强于His6-SPI38-monomer。真菌生长抑制实验显示,能够通过串联多聚体化来增强BmSPI38对酿酒酵母(Saccharomyces cerevisiae)和白色念珠菌(Candida albicans)的抑制能力。本研究成功实现BmSPI38的串联多聚体在大肠杆菌中的异源活性表达,并证实可通过串联多聚体化来增强BmSPI38的结构均一性和抗真菌能力,不仅可为培育抗真菌转基因家蚕提供重要的理论依据和新策略,还将推动BmSPI38的外源生产及在医疗领域的应用。 相似文献
6.
Claudia Ordóñez-Valencia Alejandro Alarcón Ronald Ferrera-Cerrato Laura Verónica Hernández-Cuevas 《Mycoscience》2009,50(5):380-387
Bicarbonates are often utilized in the food industry to avoid fermentation and to improve pH, flavor, and texture. In the
same manner, bicarbonates have been demonstrated to control postharvest phytopathogens; however, there are no reports describing
the effects of these chemical compounds either on soil-borne pathogens such as Sclerotinia sclerotiorum or on antagonist fungi such as Trichoderma species. This study evaluated the antifungal effect of increasing concentrations (0, 2, 4, 6, 8, 10, 25, and 50 mM) of potassium
bicarbonate (KHCO3) on the growth of Trichoderma sp. strain R39 and S. sclerotiorum under in vitro systems. Applications of KHCO3 greater than 8 mM significantly inhibited (P < 0.001) the growth of both fungi. Concentrations of KHCO3 lower than 25 mM did not affect the antagonistic effect of Trichoderma on the growth of S. sclerotiorum; however, this fungal interaction was not observed when exposed to 50 mM KHCO3 because of its strong inhibition of fungal growth. In addition, KHCO3 concentrations higher than 8 mM caused significant (P < 0.001) reduction of the sclerotium formation of S. sclerotiorum. Sclerotium germination and de novo sclerotium formation were significantly (P < 0.001) inhibited as the concentrations of KHCO3 increased. Results show the potential benefits of potassium bicarbonate for controlling both growth and development of S. sclerotiorum, although it also exerts negative effects on the Trichoderma strain that is a natural antagonist to S. sclerotiorum. 相似文献
7.
8.
Ali Dehestani Kamal Kazemitabar Gholamreza Ahmadian Nadali Babaeian Jelodar Ali Hatef Salmanian Mehdi Seyedi Heshmat Rahimian Seyedhadi Ghasemi 《Biotechnology letters》2010,32(4):539-546
The Bacillus pumilus SG2 chitinase gene (ChiS) and its truncated form lacking chitin binding (ChBD) and fibronectin type III (FnIII) domains were transformed to Arabidopsis plants and the expression, functionality and antifungal activity of the recombinant proteins were investigated. Results showed
that while the two enzyme forms showed almost equal hydrolytic activity toward colloidal chitin, they exhibited a significant
difference in antifungal activity. Recombinant ChiS in plant protein extracts displayed a high inhibitory effect on spore
germination and radial growth of hyphae in Alternaria brassicicola, Fusarium graminearum and Botrytis cinerea, while the activity of the truncated enzyme was strongly abolished. These findings demonstrate that ChBD and FnIII domains
are not necessary for hydrolysis of colloidal chitin but play an important role in hydrolysis of chitin–glucan complex of
fungal cell walls. Twenty microgram aliquots of protein extracts from ChiS transgenic lines displayed strong antifungal activity
causing up to 80% decrease in fungal spore germination. This is the first report of a Bacillus pumilus chitinase expressed in plant system. 相似文献
9.
A PCR-based method for the screening of bacterial strains with antifungal activity in suppressive soybean rhizosphere 总被引:2,自引:0,他引:2
Giacomodonato Mónica N. Pettinari M. Julia Souto Guadalupe I. Méndez Beatriz S. López Nancy I. 《World journal of microbiology & biotechnology》2001,17(1):51-55
Selection and evaluation of microbial strains for their antifungal activity in natural environments is time- and energy-consuming. We have adapted a PCR-based method to avoid these inconveniences. Soils that are naturally suppressive to plant disease were chosen as a source of antibiotic-producing bacteria. The screening was performed by means of PCR amplification using degenerate primers corresponding to peptide synthetase genes. Amplification fragments were obtained using template DNA from the rhizosphere of three different soybean fields. In order to assay their potential utility in pathogen control, several Bacillus strains were analysed for their in vitro antifungal activity by testing growth inhibition of Sclerotinia sclerotiorum. Four Bacillus sp. isolates gave a positive amplification signal, and three of them had an inhibitory effect on S. sclerotiorum growth, whereas two strains that failed to give an amplification signal did not inhibit fungal growth. These results show that PCR-based techniques could be useful to assess the presence of strains with potential use as biocontrol agents. 相似文献
10.
Liping Yang Jiatao Xie Daohong Jiang Yanping Fu Guoqing Li Fangcan Lin 《World journal of microbiology & biotechnology》2008,24(7):909-915
This paper reports the isolation from soil of Penicillium strain PY-1 with strong antagonistic activity against plant pathogenic fungi. On the basis of its morphological characteristics
and the sequence of the ITS region, strain PY-1 was identified as P. oxalicum. Strain PY-1 produces antifungal substances that suppress the mycelial growth of Sclerotinia sclerotiorum and many other plant pathogenic fungi tested; the highest antagonistic activity was detected at 72 h when cultured in a 250-ml
flask containing 80 ml potato dextrose broth. Compared with carbendazim, the relative activity of the antifungal substances
produced by strain PY-1 was approximately 4 μg active ingredient (a.i.) per milliliter. The antifungal substances were extracted
with ethyl acetate and further separated by high-performance liquid chromatography (HPLC); at least two active components
were discovered. The ability to control plant disease with strain PY-1 was confirmed with S. sclerotiorum, a widespread pathogenic fungus that attacks rapeseed (Brassica napus) and other plants. Spores (106 or 107 ml−1) and filtrate (tenfold diluted or undiluted) of strain PY-1 could significantly suppress infection and/or the extent of infection
by S. sclerotiorum of plants at seven-true-leaves stage. The potential of strain PY-1 for identifying new antibiotics to control fungal disease
and for biological control of plant disease, for example oilseed rape stem rot, is discussed. 相似文献
11.
Rodríguez MA Cabrera G Gozzo FC Eberlin MN Godeas A 《Journal of applied microbiology》2011,110(5):1177-1186
Aims: To establish the modes of action of the antagonistic fungal strain Clonostachys rosea BAFC3874 isolated from suppressive soils against Sclerotinia sclerotiorum and to determine its potential as a biocontrol agent. Methods and Results: The antagonistic activity of C. rosea BAFC3874 was determined in vitro by dual cultures. The strain effectively antagonized S. sclerotiorum in pot‐grown lettuce and soybean plants. Antifungal activity assays of C. rosea BAFC3874 grown in culture established that the strain produced antifungal compounds against S. sclerotiorum associated with secondary metabolism. High mycelial growth inhibition coincided with sclerotia production inhibition. The C. rosea strain produced a microheterogeneous mixture of peptides belonging to the peptaibiotic family. Moreover, mycoparasitism activity was observed in the dual culture. Conclusions: Clonostachys rosea strain BAFC3874 was proved to be an effective antagonist against the aggressive soil‐borne pathogen S. sclerotiorum in greenhouse experiments. The main mechanisms involve peptaibiotic metabolite production and mycoparasitism activity. Significance and Impact of the Study: Clonostachys rosea BAFC3874 may be a good fungal biological control agent against S. sclerotiorum. In addition, we were also able to isolate and identify peptaibols, an unusual family of compounds in this genus of fungi. 相似文献
12.
A new point mutation in the iron–sulfur subunit of succinate dehydrogenase confers resistance to boscalid in Sclerotinia sclerotiorum
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Research has established that mutations in highly conserved amino acids of the succinate dehydrogenase (SDH) complex in various fungi confer SDH inhibitor (SDHI) resistance. For Sclerotinia sclerotiorum (Lib.) de Bary, a necrotrophic fungus with a broad host range and a worldwide distribution, boscalid resistance has been attributed to the mutation H132R in the highly conserved SdhD subunit protein of the SDH complex. In our previous study, however, only one point mutation, A11V in SdhB (GCA to GTA change in SdhB), was detected in S. sclerotiorum boscalid‐resistant (BR) mutants. In the current study, replacement of the SdhB gene in a boscalid‐sensitive (BS) S. sclerotiorum strain with the mutant SdhB gene conferred resistance. Compared with wild‐type strains, BR and GSM (SdhB gene in the wild‐type strain replaced by the mutant SdhB gene) mutants were more sensitive to osmotic stress, lacked the ability to produce sclerotia and exhibited lower expression of the pac1 gene. Importantly, the point mutation was not located in the highly conserved sequence of the iron–sulfur subunit of SDH. These results suggest that resistance based on non‐conserved vs. conserved protein domains differs in mechanism. In addition to increasing our understanding of boscalid resistance in S. sclerotiorum, the new information will be useful for the development of alternative antifungal drugs. 相似文献
13.
Toby E. Newman Haseong Kim Yuphin Khentry Kee Hoon Sohn Mark C. Derbyshire Lars G. Kamphuis 《Molecular Plant Pathology》2023,24(8):866-881
Sclerotinia sclerotiorum is a broad host range necrotrophic fungal pathogen, which causes disease on many economically important crop species. S. sclerotiorum has been shown to secrete small effector proteins to kill host cells and acquire nutrients. We set out to discover novel necrosis-inducing effectors and characterize their activity using transient expression in Nicotiana benthamiana leaves. Five intracellular necrosis-inducing effectors were identified with differing host subcellular localization patterns, which were named intracellular necrosis-inducing effector 1–5 (SsINE1–5). We show for the first time a broad host range pathogen effector, SsINE1, that uses an RxLR-like motif to enter host cells. Furthermore, we provide preliminary evidence that SsINE5 induces necrosis via an NLR protein. All five of the identified effectors are highly conserved in globally sourced S. sclerotiorum isolates. Taken together, these results advance our understanding of the virulence mechanisms employed by S. sclerotiorum and reveal potential avenues for enhancing genetic resistance to this damaging fungal pathogen. 相似文献
14.
15.
M.A. Rodríguez C. Rothen T.E. Lo G.M. Cabrera A.M. Godeas 《Biocontrol Science and Technology》2015,25(12):1388-1409
The fungal diversity structures of soils that are suppressive and non-suppressive to Sclerotinia sclerotiorum were characterised and screened for fungal strains antagonistic to the S. sclerotiorum pathogen. Soil suppressiveness was associated with a particular fungal diversity structure. Principal component analysis showed that antagonism by fungal species in suppressive soils was associated with the occurrence of Fusarium oxysporum, Fusarium solani, Talaromyces flavus var. flavus and Clonostachys rosea f. rosea. In particular, C. rosea f. rosea occurred exclusively in suppressive soil samples, suggesting that this morpho-species plays an important role in suppression of S. sclerotiorum diseases. One strain of C. rosea f. rosea (BAFC1646) was selected for further experiments. Dual-culture assays confirmed the antagonistic behaviour of C. rosea f. rosea BAFC1646 against three different S. sclerotiorum strains. Antifungal activity was corroborated by diffusion assays with metabolite extracts. Greenhouse assays with soybean plants showed that the selected C. rosea f. rosea strain reduced the percentage of dead plants when co-inoculated with S. sclerotiorum. In addition, inclusion of C. rosea f. rosea alone increased shoot lengths significantly. In this work, we established the involvement of fungal species in soil suppressiveness and in further assays confirmed that C. rosea f. rosea BAFC1646 exhibits a bioprotective effect against S. sclerotiorum in soybean plants. 相似文献
16.
Fungi isolated from Sclerotia ofSclerotium cepivorum and from soil and their effects upon the pathogen 总被引:1,自引:0,他引:1
Summary Data are presented on the antagonistic effects of the fungi isolated from sclerotia ofSclerotium cepivorum and from nonrhizosphere soil taken from around the roots of infected onions upon mycelial growth and sclerotial germination
ofS. cepivorum. Most of the isolated fungi especiallyPenicillium species were antagonistic to mycelial growth. Sclerotial germination was slightly inhibited by diffusates of these fungal
isolates.
Testing the antifungal effect of someAllium extracts against the fungal isolates by the inhibition zone method showed that garlic extract has the greatest antifungal
effects and onion extract is the least potent. However, spore germination tests indicated that onion extract completely inhibits
the spore germination of all test fungi. The role of host-plant extracts in stimulating sclerotial germination is discussed. 相似文献
17.
The effect of pollen and senescent petals on the suppression of alfalfa (Medicago sativa L.) blossom blight (Sclerotinia sclerotiorum) by the mycoparasite Coniothyrium minitans was investigated. When incubated at 20°C for 39 h, germination of conidia of C. minitans and ascospores of S. sclerotiorum was 99.9 and 98.6%, respectively, in the presence of alfalfa pollen (9×104 pollen grains mL?1), whereas spore germination of both organisms was <0.5% in the absence of pollen (in water). In the presence of a commercial pollen product, Swiss? pollen granules (mainly bee pollen), germination was 99.6% for C. minitans and 98.3% for S. sclerotiorum when the pollen concentration was 1.0% (w/v). When the pollen concentration was reduced to 0.1% (w/v), germination was reduced to 13.0% for C. minitans and 10.8% for S. sclerotiorum. Tests on detached alfalfa florets showed that the colonization of alfalfa florets by S. sclerotiorum was significantly suppressed by C. minitans in the presence of pollen (1.0% Swiss? pollen granules), especially when C. minitans was inoculated 1-day before S. sclerotiorum. In vivo inoculation tests revealed that the efficacy of C. minitans in the protection of alfalfa pods from the infection by S. sclerotiorum was affected by the time at which C. minitans was applied. When C. minitans was applied on young blossoms of alfalfa at the anthesis stage, pod infection was 96.6% for the treatment of C. minitans+S. sclerotiorum and 99.6% for the treatment of S. sclerotiorum alone. However, when C. minitans was applied on senescent petals of alfalfa at the pod development stage, pod infection was 8.0% for the treatment of C. minitans+S. sclerotiorum compared to 90.8% for the treatment of S. sclerotiorum alone. These results suggest that timing of the application of C. minitans is critical for the mycoparasite to compete with S. sclerotiorum for the source of nutrients from pollen and senescent petals, and for its control of alfalfa blossom blight caused by S. sclerotiorum. 相似文献
18.
Xiuqin Gao Xie Dang Fengting Yan Yuhua Li Jing Xu Shifu Tian Yaling Li Kun Huang Wenwei Lin Deshu Lin Zonghua Wang Airong Wang 《Molecular Plant Pathology》2022,23(8):1091-1106
Sclerotinia sclerotiorum is a devastating pathogen that infects a broad range of host plants. The mechanism underlying plant defence against fungal invasion is still not well characterized. Here, we report that ANGUSTIFOLIA (AN), a CtBP family member, plays a role in the defence against S. sclerotiorum attack. Arabidopsis an mutants exhibited stronger resistance to S. sclerotiorum at the early stage of infection than wild-type plants. Accordingly, an mutants exhibited stronger activation of pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) responses, including mitogen-activated protein kinase activation, reactive oxygen species accumulation, callose deposition, and the expression of PTI-responsive genes, upon treatment with PAMPs/microbe-associated molecular patterns. Moreover, Arabidopsis lines overexpressing AN were more susceptible to S. sclerotiorum and showed defective PTI responses. Our luminometry, bimolecular fluorescence complementation, coimmunoprecipitation, and in vitro pull-down assays indicate that AN interacts with allene oxide cyclases (AOC), essential enzymes involved in jasmonic acid (JA) biosynthesis, negatively regulating JA biosynthesis in response to S. sclerotiorum infection. This work reveals AN is a negative regulator of the AOC-mediated JA signalling pathway and PTI activation. 相似文献
19.
Furanocoumarins are well-known natural products that occur in the most evolved genera of Apiaceae family. This compounds were
found to have cytotoxic, phytotoxic, photosensitizing, insecticidal, antibacterial and high antifungal effects. Aviprin is
considered as a linear furanocoumarin substituted at C8 with an oxygenated prenyl residue. In this study we found that aviprin
is a bioactive compound that exhibits high antibacterial, antifungal and phytotoxic activity. The compound stunted the germination
of lettuce seeds with IC50 value of 0.270 mg/ml. The compound also inhibited the mycelia growth of Sclerotinia sclerotiorum. Aviprin indicated antibacterial activity against tested gram negative and positive bacteria with inhibition zone of 19–23.5
mm. Our results shown that aviprin can play an allelopatic role for plant. 相似文献
20.
Vivek K. Bajpai Hak Ryul Kim Ching Tsang Hou Sun Chul Kang 《Journal of industrial microbiology & biotechnology》2009,36(5):695-704
Microbial modification of polyunsaturated fatty acids can often lead to special changes in their structure and in biological
potential. Therefore, the aim of this study was to develop potential antifungal agents through the microbial conversion of
docosahexaenoic acid (DHA). Bioconverted oil extract of docosahexaenoic acid (bDHA), obtained from the microbial conversion
of docosahexaenoic acid (DHA) by Pseudomonas aeruginosa PR3, was assessed for its in vitro and in vivo antifungal potential. Mycelial growth inhibition of test plant pathogens,
such as Botrytis cinerea, Colletotrichum capsici, Fusarium oxysporum, Fusarium solani, Phytophthora capsici, Rhizoctonia solani and Sclerotinia sclerotiorum, was measured in vitro. bDHA (5 μl disc−1) inhibited 55.30–65.90% fungal mycelium radial growth of all the tested plant pathogens. Minimum inhibitory concentrations
(MICs) of bDHA against the tested plant pathogens were found in the range of 125–500 μg ml−1. Also, bDHA had a strong detrimental effect on spore germination for all the tested plant pathogens. Further, three plant
pathogenic fungi, namely C. capsici, F. oxysporum and P. capsici, were subjected to an in vivo antifungal screening. bDHA at higher concentrations revealed a promising antifungal effect
in vivo as compared to the positive control oligochitosan. Furthermore, elaborative study of GC-MS analysis was conducted
on bioconverted oil extract of DHA to identify the transformation products present in bDHA. The results of this study indicate
that the oil extract of bDHA has potential value of industrial significance to control plant pathogenic fungi. 相似文献