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1.
Fum3p, a 2-Ketoglutarate-Dependent Dioxygenase Required for C-5 Hydroxylation of Fumonisins in Fusarium verticillioides 下载免费PDF全文
Fumonisins are polyketide-derived mycotoxins produced by several agriculturally important Fusarium species. The B series fumonisins, FB1, FB2, FB3, and FB4, are fumonisins produced by wild-type Fusarium verticillioides strains, differing in the number and location of hydroxyl groups attached to the carbon backbone. We characterized the protein encoded by FUM3, a gene in the fumonisin biosynthetic gene cluster. The 33-kDa FUM3 protein (Fum3p) was heterologously expressed and purified from Saccharomyces cerevisiae. Yeast cells expressing the Fum3p converted FB3 to FB1, indicating that Fum3p catalyzes the C-5 hydroxylation of fumonisins. This result was verified by assaying the activity of Fum3p purified from yeast cells. The C-5 hydroxylase activity of purified Fum3p required 2-ketoglutarate, Fe2+, ascorbic acid, and catalase, all of which are required for 2-ketoglutarate-dependent dioxygenases. The protein also contains two His motifs that are highly conserved in this family of dioxygenases. Thus, Fum3p is a 2-ketoglutarate-dependent dioxygenase required for the addition of the C-5 hydroxyl group of fumonisins. 相似文献
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3.
Rajan Sharma Ram P. Thakur Senapathy Senthilvel Spurthi Nayak S. Veera Reddy Veeranki Panduranga Rao Rajeev K. Varshney 《Mycopathologia》2011,171(3):223-230
Fusarium species are dominant within the sorghum grain mold complex. Some species of Fusarium involved in grain mold complex produce mycotoxins, such as fumonisins. An attempt was made to identify Fusarium spp. associated with grain mold complex in major sorghum-growing areas in India through AFLP-based grouping of the isolates
and to further confirm the species by sequencing part of α-Elongation factor gene and comparing the sequences with that available in the NCBI database. The dendrogram generated from the AFLP data clustered
the isolates into 5 groups. Five species of Fusarium—F. proliferatum, F. thapsinum, F. equiseti, F. andiyazi and F. sacchari were identified based on sequence similarity of α-Elongation factor gene of the test isolates with those in the NCBI database. Fusarium thapsinum was identified as predominant species in Fusarium—grain mold complex in India and F. proliferatum as highly toxigenic for fumonisins production. Analysis of molecular variance (AMOVA) revealed 54% of the variation in the
AFLP patterns of 63 isolates was due to the differences between Fusarium species, and 46% was due to differences between the strains within a species. 相似文献
4.
Lincy S. V. Chandrashekar A. Narayan M. S. Sharma Rajan Thakur R. P. 《World journal of microbiology & biotechnology》2011,27(4):981-989
In this study a total of 167 isolates collected from different food materials (68.8% from sorghum and the remaining from various
other food materials) were assayed by PCR for amplification of the tri 5 gene present in trichothecene-producing Fusaria. Amplification of the tri 5 fragment was observed in 45 isolates (39 isolates from sorghum and 6 isolates from vegetables). Isolates found positive for
presence of the tri 5 gene were classified into different morphological groups based on their cultural and conidial characters; 11 of the tri 5 positive isolates from moldy grains of sorghum, one from each morphology group were selected for further analyses. Five deoxynivalenol
producers and three deoxynivalenol and Fusarenon-X producers were detected by analysing culture filtrates of the 11 isolates
using GC-MS. One isolate each were identified as producers of NIV alone, or NIV along with DON or DAS toxins. Identification
of these isolates to the species level was carried out using spore morphology and sequence comparison of the translation elongation
factor 1-alpha (EF-1α) gene against the database as well as using phylogenetic analyses. The isolates were identified as Fusarium
proliferatum (6), F. nelsonii (2), F. equiseti (1), F. thapsinum (1) and F. sacchari (1). Amplified Fragment Length Polymorphism (AFLP) based grouping clustered the isolates of same species together. This is
the first detailed study of trichothecene production by Fusarium spp. associated with sorghum grain mold in India and the identification of F. nelsonii and F. thapsinum as producers of trichothecenes. 相似文献
5.
Ammar Madania Merfat Altawil Walid Naffaa Paul H Volker Mohammad Hawat 《Journal of Phytopathology》2013,161(7-8):452-458
Maize is the third most important cereal after wheat and barley in Syria. Maize plants are attacked by several Fusarium species causing mainly stalk and ear rot of maize which poses a major impact worldwide. Identification of Fusarium species is important for disease control and for assessment of exposure risk to mycotoxines. To identify Fusarium species attacking maize in Syria, a total of 32 Fusarium isolates were recovered from maize ears collected from four different geographical regions, mainly from Ghouta surrounding Damascus. Fusarium isolates were identified based on morphology and on partial DNA sequencing of the TEF1‐α and rDNA/ITS genes. The majority (26 of 32) of these isolates was identified as F. verticillioides (subdivided into four groups), whereas three isolates turned out to be F. thapsinum, F. equiseti and F. andiyazi. The remaining three isolates were close to F. andiyazi, although further investigation is needed to confirm whether they represent a yet undescribed species. Furthermore, our results showed that sequencing the TEF1‐α gene is much more informative than sequencing of the rDNA/ITS region for Fusarium identification at the species level. PCR analysis showed that only F. verticillioides isolates were potentially fumonisin producers and that only the F. equiseti isolate was potentially trichotecene producer. This is the first report on Fusarium thapsinum, F. equiseti and F. andiyazi attacking maize in Syria. 相似文献
6.
Zearalenone (ZON) is a non-steroidal estrogenic mycotoxin produced by plant pathogenic species ofFusarium. As a consequence of infection withF. culmorum andF. graminearum, ZON can be found in cereals and derived food products. Several countries have established monitoring programs and guidelines
for ZON levels in grain intended for human consumption and animal feed. We have developed a sensitive yeast bioassay allowing
detection of the estrogenic activity of ZON in cereal extracts without requiring further clean up steps. The high sensitivity
makes this assay suitable for low cost monitoring of contamination of small grain cereals with estrogenicFusarium mycotoxins, but also attractive as a tool for basic research. We have successfully used yeast indicator strains to screen
for mutants ofF. graminearum which no longer produce detectable amounts of ZON, and have identified a plant cDNA encoding a ZON detoxification enzyme.
Presented at the 25th Mykotoxin Workshop in Giessen, Germany, May 19–21, 2003 相似文献
7.
Fusarium genomic resources: Tools to limit crop diseases and mycotoxin contamination 总被引:1,自引:0,他引:1
It has been almost 10 years since Joan Bennett suggested that fungal biologists create a “wish list” for fungal genome sequences
(Bennett JW. White paper: Genomics for filamentous fungi. Fungal Genet Biol 1997; 21: 3–7). The availability of over 200 review
papers concerning fungal genomics is a reflection of significant progress with a diversity of fungal species. Although much
progress has been made, the use of genomic data to study mycotoxin synthesis and function, pathogenesis and other aspects
of fungal biology is in its infancy. Here, we briefly present the status of publicly available genomic resources for Fusarium, a genus of important plant pathogenic and mycotoxin-producing fungi of worldwide concern. Preliminary examination of microarray
data collected from F. verticillioides liquid cultures provides evidence of widespread differential gene expression over time. 相似文献
8.
Mostafa Abedi-Tizaki 《Archives Of Phytopathology And Plant Protection》2013,46(8):676-687
In order to determine the crown and root agents and their mycotoxins produced in different growth stages of wheat including seedling, tillering and heading, sampling was done in north of Iran, during 2011–2012. From 160 isolates of Fusarium, eight species were obtained including F. graminearum, F. culmorum, F. equiseti, F. nygamai, F. semitectum, F. solani, F. acuminatum and F. oxysporum. Sampling at different growth stages showed that F. graminearum was the predominant causal agent of crown and root at the heading stage, whereas other species of Fusarium were mostly observed at the seedling and tillering stages. Moreover, identification of pathogenic species was confirmed using species-specific primers pairs. In F. graminearum isolates, presence of Tri13 gene, responsible for nivalenol (NIV) and deoxynivalenol (DON) mycotoxins biosynthesis, was detected using specific PCR primers. Finally, the ability of trichothecene production of five F. graminearum isolates was confirmed with high-performance liquid chromatography. 相似文献
9.
PCR analysis was used to detect Fusarium species generically, as well as the mycotoxin-producing species F.␣subglutinans, F. proliferatum, and F. verticillioides in leaf axil and other maize tissues during ear fill in a multiyear study in central Illinois. The frequency of Fusarium detected varied from site to site and year to year. Fusarium was generically detected more frequently in leaf axil material than in leaf/husk lesions. In two growing seasons, the leaf
axil samples were also tested for the presence of the mycotoxin producing species F. proliferatum, F. subglutinans, and F. verticillioides. Overall, F. proliferatum and F. verticillioides were detected less often than F. subglutinans. Fusarium was generically and specifically detected most commonly where visible fungal growth was present in leaf axil material.
Disclaimer: The mention of firm names or trade products in this article does not imply that they are endorsed or recommended
by the United States Department of Agriculture over other firms or similar products not mentioned. 相似文献
10.
Biological detoxification of the mycotoxin deoxynivalenol and its use in genetically engineered crops and feed additives 总被引:2,自引:0,他引:2
Karlovsky P 《Applied microbiology and biotechnology》2011,91(3):491-504
Deoxynivalenol (DON) is the major mycotoxin produced by Fusarium fungi in grains. Food and feed contaminated with DON pose a health risk to humans and livestock. The risk can be reduced
by enzymatic detoxification. Complete mineralization of DON by microbial cultures has rarely been observed and the activities
turned out to be unstable. The detoxification of DON by reactions targeting its epoxide group or hydroxyl on carbon 3 is more
feasible. Microbial strains that de-epoxidize DON under anaerobic conditions have been isolated from animal digestive system.
Feed additives claimed to de-epoxidize trichothecenes enzymatically are on the market but their efficacy has been disputed.
A new detoxification pathway leading to 3-oxo-DON and 3-epi-DON was discovered in taxonomically unrelated soil bacteria from
three continents; the enzymes involved remain to be identified. Arabidopsis, tobacco, wheat, barley, and rice were engineered to acetylate DON on carbon 3. In wheat expressing DON acetylation activity,
the increase in resistance against Fusarium head blight was only moderate. The Tri101 gene from Fusarium sporotrichioides was used; Fusarium graminearum enzyme which possesses higher activity towards DON would presumably be a better choice. Glycosylation of trichothecenes occurs
in plants, contributing to the resistance of wheat to F. graminearum infection. Marker-assisted selection based on the trichothecene-3-O-glucosyltransferase gene can be used in breeding for
resistance. Fungal acetyltransferases and plant glucosyltransferases targeting carbon 3 of trichothecenes remain promising
candidates for engineering resistance against Fusarium head blight. Bacterial enzymes catalyzing oxidation, epimerization, and less likely de-epoxidation of DON may extend this
list in future. 相似文献
11.
FUM9 Is Required for C-5 Hydroxylation of Fumonisins and Complements the Meitotically Defined Fum3 Locus in Gibberella moniliformis 下载免费PDF全文
Robert A. E. Butchko Ronald D. Plattner Robert H. Proctor 《Applied microbiology》2003,69(11):6935-6937
Deletion of the Gibberella moniliformis FUM9 gene resulted in mutants that produce only fumonisins that lack a C-5 hydroxyl group. This phenotype is identical to that of previously described mutants with defective alleles at the meiotically defined Fum3 locus. Transformation with a wild-type FUM9 gene into a Fum3-defective mutant restored wild-type fumonisin production. These results indicate that the FUM9 protein catalyzes the C-5 hydroxylation of fumonisins and that FUM9 and the Fum3 locus are the same gene. 相似文献
12.
S. Datta R. G. Choudhary Md. Shamim Vishwa Dhar 《Archives Of Phytopathology And Plant Protection》2013,46(6):558-566
Fusarium species causing wilt diseases in different plants were characterised by comparing nonpathogenic and different pathogenic species using rDNA RFLP analysis. The ITS (internal transcribed spacer) region of 12 isolates belonging to the section Elegans, Laseola, Mortiella, Discolor, Gibbosum, Lateritium and Sporotrichiella were amplified by universal ITS primers (ITS-1 and ITS-4) using polymerase chain reaction (PCR). Amplified products, which ranged from 522 to 565 bp were obtained from all 12 Fusarium isolates. The amplified products were digested with seven restriction enzymes, and restriction fragment length polymorphism (RFLP) patterns were analysed. A dendrogram derived from PCR-RFLP analysis of the rDNA region divided the Fusarium isolates into three major groups. Assessment of molecular variability based on rDNA RFLP clearly indicated that Fusarium species are heterogeneous and most of the forma speciales have close evolutionary relationships. 相似文献
13.
Andrew Taylor Viktória Vágány Alison C. Jackson Richard J. Harrison Alessandro Rainoni John P. Clarkson 《Molecular Plant Pathology》2016,17(7):1032-1047
Pathogenic isolates of Fusarium oxysporum, distinguished as formae speciales (f. spp.) on the basis of their host specificity, cause crown rots, root rots and vascular wilts on many important crops worldwide. Fusarium oxysporum f. sp. cepae (FOC) is particularly problematic to onion growers worldwide and is increasing in prevalence in the UK. We characterized 31 F. oxysporum isolates collected from UK onions using pathogenicity tests, sequencing of housekeeping genes and identification of effectors. In onion seedling and bulb tests, 21 isolates were pathogenic and 10 were non‐pathogenic. The molecular characterization of these isolates, and 21 additional isolates comprising other f. spp. and different Fusarium species, was carried out by sequencing three housekeeping genes. A concatenated tree separated the F. oxysporum isolates into six clades, but did not distinguish between pathogenic and non‐pathogenic isolates. Ten putative effectors were identified within FOC, including seven Secreted In Xylem (SIX) genes first reported in F. oxysporum f. sp. lycopersici. Two highly homologous proteins with signal peptides and RxLR motifs (CRX1/CRX2) and a gene with no previously characterized domains (C5) were also identified. The presence/absence of nine of these genes was strongly related to pathogenicity against onion and all were shown to be expressed in planta. Different SIX gene complements were identified in other f. spp., but none were identified in three other Fusarium species from onion. Although the FOC SIX genes had a high level of homology with other f. spp., there were clear differences in sequences which were unique to FOC, whereas CRX1 and C5 genes appear to be largely FOC specific. 相似文献
14.
Birth,death and horizontal transfer of the fumonisin biosynthetic gene cluster during the evolutionary diversification of Fusarium 总被引:1,自引:0,他引:1
François Van Hove Antonia Susca Gaetano Stea Mark Busman Theo van der Lee Cees Waalwijk Todd J. Ward 《Molecular microbiology》2013,90(2):290-306
Fumonisins are a family of carcinogenic secondary metabolites produced by members of the Fusarium fujikuroi species complex (FFSC) and rare strains of Fusarium oxysporum. In Fusarium, fumonisin biosynthetic genes (FUM) are clustered, and the cluster is uniform in gene organization. Here, sequence analyses indicated that the cluster exists in five different genomic contexts, defining five cluster types. In FUM gene genealogies, evolutionary relationships between fusaria with different cluster types were largely incongruent with species relationships inferred from primary‐metabolism (PM) gene genealogies, and FUM cluster types are not trans‐specific. In addition, synonymous site divergence analyses indicated that three FUM cluster types predate diversification of FFSC. The data are not consistent with balancing selection or interspecific hybridization, but they are consistent with two competing hypotheses: (i) multiple horizontal transfers of the cluster from unknown donors to FFSC recipients and (ii) cluster duplication and loss (birth and death). Furthermore, low levels of FUM gene divergence in F. bulbicola, an FFSC species, and F. oxysporum provide evidence for horizontal transfer of the cluster from the former, or a closely related species, to the latter. Thus, uniform gene organization within the FUM cluster belies a complex evolutionary history that has not always paralleled the evolution of Fusarium. 相似文献
15.
Robert H. Proctor Susan P. McCormick Nancy J. Alexander Anne E. Desjardins 《Molecular microbiology》2009,74(5):1128-1142
Trichothecenes are terpene‐derived secondary metabolites produced by multiple genera of filamentous fungi, including many plant pathogenic species of Fusarium. These metabolites are of interest because they are toxic to animals and plants and can contribute to pathogenesis of Fusarium on some crop species. Fusarium graminearum and F. sporotrichioides have trichothecene biosynthetic genes (TRI) at three loci: a 12‐gene TRI cluster and two smaller TRI loci that consist of one or two genes. Here, comparisons of additional Fusarium species have provided evidence that TRI loci have a complex evolutionary history that has included loss, non‐functionalization and rearrangement of genes as well as trans‐species polymorphism. The results also indicate that the TRI cluster has expanded in some species by relocation of two genes into it from the smaller loci. Thus, evolutionary forces have driven consolidation of TRI genes into fewer loci in some fusaria but have maintained three distinct TRI loci in others. 相似文献
16.
To identify Fusarium species associated with diseases of root and basal plate of onion, surveys were conducted in seven provinces of Turkey in 2007. Samplings were performed in 223 fields, and 332 isolates belonging to 7 Fusarium spp. were obtained. The isolates were identified as F. oxysporum, F. solani, F. acuminatum, F. equiseti, F. proliferatum, F. redolens, and F. culmorum based on morphological and cultural characteristics. Also, species‐specific primers were used to confirm the identity of Fusarium species. F. oxysporum was the most commonly isolated species, comprising 66.57% of the total Fusarium species. F. redolens was identified for the first time in onion‐growing areas of Turkey. Selected isolates of each species were evaluated for their aggressiveness on onion plant. F. oxysporum, F. solani, F. acuminatum, F. proliferatum, and F. redolens were highly pathogenic, causing severe damping‐off on onion plants cv. Texas Early Grano. Inter‐simple sequence repeats (ISSR) markers revealed a high degree of intra‐ and interspecific polymorphisms among Fusarium spp. 相似文献
17.
Jonathan Scauflaire Marie Godet Mélanie Gourgue Charlotte Liénard Françoise Munaut 《Fungal biology》2012,116(10):1073-1080
Maize contamination with Fusarium species is one of the major sources of mycotoxins in food and feed derivates. In the present study, a LightCycler® real-time PCR method using hybridization probes was developed for the specific identification, detection, and quantification of Fusarium proliferatum, Fusarium subglutinans, Fusarium temperatum, and Fusarium verticillioides, four mycotoxin-producing pathogens of maize. Primers and hybridization probes were designed to target the translation elongation factor 1α (EF-1α) gene of F. subglutinans and F. temperatum or the calmodulin (Cal) gene of F. proliferatum and F. verticillioides. The specificity of the real-time PCR assays was confirmed for the four Fusarium species, giving no amplification with DNA from other fungal species commonly recovered from maize. The assays were found to be sensitive, detecting down to 5 pg and 50 pg of Fusarium DNA in simplex and multiplex conditions respectively, and were able to quantify pg-amounts of Fusarium DNA in artificially Fusarium-contaminated maize samples. The real-time PCR method developed provides a useful tool for routine identification, detection, and quantification of toxigenic Fusarium species in maize. 相似文献
18.
Identification and validation of a major QTL conferring crown rot resistance in hexaploid wheat 总被引:1,自引:0,他引:1
J. Ma H. B. Li C. Y. Zhang X. M. Yang Y. X. Liu G. J. Yan C. J. Liu 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(6):1119-1128
Crown rot (CR), caused by various Fusarium species, is a chronic wheat disease in Australia. As part of our objective of improving the efficiency of breeding CR resistant
wheat varieties, we have been searching for novel sources of resistance. This paper reports on the genetic control of one
of these newly identified resistant genotypes, ‘CSCR6’. A population derived from a cross between CSCR6 and an Australian
variety ‘Lang’ was analyzed using two Fusarium isolates belonging to two different species, one Fusarium pseudograminearum and the other Fusarium graminearum. The two isolates detected QTL with the same chromosomal locations and comparable magnitudes, indicating that CR resistance
is not species-specific. The resistant allele of one of the QTL was derived from ‘CSCR6’. This QTL, designated as Qcrs.cpi-3B, was located on the long arm of chromosome 3B and explains up to 48.8% of the phenotypic variance based on interval mapping
analysis. Another QTL, with resistant allele from the variety ‘Lang’, was located on chromosome 4B. This QTL explained up
to 22.8% of the phenotypic variance. A strong interaction between Qcsr.cpi-3B and Qcsr.cpi-4B was detected, reducing the maximum effect of Qcrs.cpi-3B to 43.1%. The effects of Qcrs.cpi-3B were further validated in four additional populations and the presence of this single QTL reduced CR severity by up to 42.1%.
The fact that significant effects of Qcrs.cpi-3B were detected across all trials with different genetic backgrounds and with the use of isolates belonging to two different
Fusarium species make it an ideal target for breeding programs as well as for further characterization of the gene(s) involved in
its resistance. 相似文献
19.
A study has been carried out in Argentina on samples of corn genotypes from a breeding station as well as in commercially available corn meal. All samples were analyzed for fungal infection and aflatoxin B1.Mycological analysis of corn genotypes showed the presence of three principal genera of filamentous fungi Fusarium (100%), Penicillium (67%) and Aspergillus (60%). In the genus Fusarium three species were identified, F. moniliforme (42%), F. nygamai (56%) andF. proliferatum (1.8%). Eight species ofPenicillium were identified, the predominant species isolated were P. minioluteum, P. funiculosum and P. variabile. In the genus ranked third in isolation frequency, two species were identified, A. flavus and A. parasiticus, the percentage of infection was 78% and 21%, respectively. Only one corn genotype was contaminated with aflatoxin B1 at a level of 5 ppb. The cornmeal samples showed great differences in fungal contamination, the values ranging from 1 × 101 to 7 × 105 cfu g–1. Fusarium (68%), Aspergillus (35%) and Penicillium (21%) were the most frequent genera isolated. Among the genus, Aspergillus, A. parasiticus (38%) was the most frequent species isolated. All the samples of corn meal were negative to aflatoxin B1. These results indicate a low degree of human exposure to aflatoxins in Argentina through the ingestion of maize or corn meal.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献