Browsing by Author "Wingfield, Brenda D."

Now showing 1 - 7 of 7
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    Genome sequences of Knoxdaviesia capensis and K. proteae (Fungi: Ascomycota) from Protea trees in South Africa
    (BioMed Central, 2016) Aylward, Janneke; Steenkamp, Emma T.; Dreyer, Leanne L.; Roets, Francois; Wingfield, Brenda D.; Wingfield, Michael J.
    Two closely related ophiostomatoid fungi, Knoxdaviesia capensis and K. proteae, inhabit the fruiting structures of certain Protea species indigenous to southern Africa. Although K. capensis occurs in several Protea hosts, K. proteae is confined to P. repens. In this study, the genomes of K. capensis CBS139037 and K. proteae CBS140089 are determined. The genome of K. capensis consists of 35,537,816 bp assembled into 29 scaffolds and 7940 predicted protein-coding genes of which 6192 (77.98 %) could be functionally classified. K. proteae has a similar genome size of 35,489,142 bp that is comprised of 133 scaffolds. A total of 8173 protein-coding genes were predicted for K. proteae and 6093 (74.55 %) of these have functional annotations. The GC-content of both genomes is 52.8 %.
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    Identification of the gene for β-fructofuranosidase from Ceratocystis moniliformis CMW 10134 and characterization of the enzyme expressed in Saccharomyces cerevisiae
    (BioMed Central, 2013-11) Van Wyk, Niel; Trollope, Kim M.; Steenkamp, Emma T.; Wingfield, Brenda D.; Volschenk, Heinrich
    Background: β-Fructofuranosidases (or invertases) catalyse the commercially-important biotransformation of sucrose into short-chain fructooligosaccharides with wide-scale application as a prebiotic in the functional foods and pharmaceutical industries. Results: We identified a β-fructofuranosidase gene (CmINV) from a Ceratocystis moniliformis genome sequence using protein homology and phylogenetic analysis. The predicted 615 amino acid protein, CmINV, grouped with an existing clade within the glycoside hydrolase (GH) family 32 and showed typical conserved motifs of this enzyme family. Heterologous expression of the CmINV gene in Saccharomyces cerevisiae BY4742Δsuc2 provided further evidence that CmINV indeed functions as a β-fructofuranosidase. Firstly, expression of the CmINV gene complemented the inability of the Δsuc2 deletion mutant strain of S. cerevisiae to grow on sucrose as sole carbohydrate source. Secondly, the recombinant protein was capable of producing short-chain fructooligosaccharides (scFOS) when incubated in the presence of 10% sucrose. Purified deglycosylated CmINV protein showed a molecular weight of ca. 66 kDa and a Km and Vmax on sucrose of 7.50 mM and 986 μmol/min/mg protein, respectively. Its optimal pH and temperature conditions were determined to be 6.0 and 62.5°C, respectively. The addition of 50 mM LiCl led to a 186% increase in CmINV activity. Another striking feature was the relatively high volumetric production of this protein in S. cerevisiae as one mL of supernatant was calculated to contain 197 ± 6 International Units of enzyme. Conclusion: The properties of the CmINV enzyme make it an attractive alternative to other invertases being used in industry.
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    IMA Genome - F13 : Draft genome sequences of Ambrosiella cleistominuta, Cercospora brassicicola, C. citrullina, Physcia stellaris, and Teratosphaeria pseudoeucalypti
    (BMC (part of Springer Nature), 2020-09-24) Wilken, P. Markus; Aylward, Janneke; Chand, Ramesh; Grewe, Felix; Lane, Frances A.; Sinha, Shagun; Ametrano, Claudio; Distefano, Isabel; Divakar, Pradeep K.; Duong, Tuan A.; Huhndorf, Sabine; Kharwar, Ravindra N.; Lumbsch, P. Markus; Navathe, Sudhir; Pérez, Carlos A.; Ramírez-Berrutti, Nazaret; Sharma, Rohit; Sun, Yukun; Wingfield, Brenda D.; Wingfield, Michael J.
    Draft genomes of the fungal species Ambrosiella cleistominuta, Cercospora brassicicola, C. citrullina, Physcia stellaris, and Teratosphaeria pseudoeucalypti are presented. Physcia stellaris is an important lichen forming fungus and Ambrosiella cleistominuta is an ambrosia beetle symbiont. Cercospora brassicicola and C. citrullina are agriculturally relevant plant pathogens that cause leaf-spots in brassicaceous vegetables and cucurbits respectively. Teratosphaeria pseudoeucalypti causes severe leaf blight and defoliation of Eucalyptus trees. These genomes provide a valuable resource for understanding the molecular processes in these economically important fungi.
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    IMA Genome-F 11: Draft genome sequences of Fusarium xylarioides, Teratosphaeria gauchensis and T. zuluensis and genome annotation for Ceratocystis fimbriata
    (BMC (part of Springer Nature), 2019-09-13) Wingfield, Brenda D.; Fourie, Arista; Simpson, Melissa C.; Bushula-Njah, Vuyiswa S.; Aylward, Janneke; Barnes, Irene; Coetzee, Martin P. A.; Dreyer, Leanne L.; Duong, Tuan A.; Geiser, David M.; Roets, Francois; Steenkamp, E. T.; Van Der Nest, Magriet A.; van Heerden, Carel J.; Wingfield, Michael J.
    ENGLISH ABSTRACT: Draft genomes of the fungal species Fusarium xylarioides, Teratosphaeria gauchensis and T. zuluensis are presented. In addition an annotation of the genome of Ceratocystis fimbriata is presented. Overall these genomes provide a valuable resource for understanding the molecular processes underlying pathogenicity and potential management strategies of these economically important fungi.
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    Killer yeasts - cause of stuck fermentations in a wine cellar
    (South African Society for Enology and Viticulture, 1986) Van Vuuren, H. J. J.; Wingfield, Brenda D.
    Sluggish fermentations in five fermenters in a wine cellar were investigated. Methylene blue-stains of yeast suspensions revealed that approximately 90% of the total yeast population in each of the fermenters were dead. The viable cells in each fermenter were killer yeasts. Polyacrylamide gel electrophoresis of total soluble cell proteins showed that the same killer yeast occurred in each of the five fermenters. The effect of killer yeast on viability and fermentation activity of the wine yeast was studied in an enriched grape juice medium at 20°C and 30°C. Death rate of the wine yeast was considerably higher in the presence of the killer yeast and fermentations were retarded at both temperatures. The killer yeast induced flocculation of the non-flocculent wine yeast.
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    Nine draft genome sequences of Claviceps purpurea s.lat., including C. arundinis, C. humidiphila, and C. cf. spartinae, pseudomolecules for the pitch canker pathogen Fusarium circinatum, draft genome of Davidsoniella eucalypti, Grosmannia galeiformis, Quambalaria eucalypti, and Teratosphaeria destructans
    (International Mycological Association, 2018-12-01) Wingfield, Brenda D.; Liu, Miao; Nguyen, Hai D. T.; Lane, Frances A.; Morgan, Seamus W.; De Vos, Lieschen; Wilken, P. M.; Duong, Tuan A.; Aylward, Janneke; Coetzee, Martin P. A.; Dadej, Kasia; De Beer, Z. W.; Findlay, Wendy; Havenga, Minette; Kolarik, Miroslav; Menzies, Jim G.; Naidoo, Kershney; Pochopski, Olivia; Shoukouhi, Parivash; Santana, Quentin C.; Seifert, Keith A.; Soal, Nicole; Steenkamp, Emma T.; Tatham, Catherine T.; Van Der Nest, Margriet A.; Wingfield, Michael J.
    This genome announcement includes draft genomes from Claviceps purpurea s.lat., including C. arundinis, C. humidiphila and C. cf. spartinae. The draft genomes of Davidsoniella eucalypti, Quambalaria eucalypti and Teratosphaeria destructans, all three important eucalyptus pathogens, are presented. The insect associate Grosmannia galeiformis is also described. The pine pathogen genome of Fusarium circinatum has been assembled into pseudomolecules, based on additional sequence data and by harnessing the known synteny within the Fusarium fujikuroi species complex. This new assembly of the F. circinatum genome provides 12 pseudomolecules that correspond to the haploid chromosome number of F. circinatum. These are comparable to other chromosomal assemblies within the FFSC and will enable more robust genomic comparisons within this species complex.
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    A plant pathology perspective of fungal genome sequencing
    (International Mycological Association, 2017) Aylward, Janneke; Steenkamp, Emma T.; Dreyer, Leanne L.; Roets, Francois; Wingfield, Brenda D.; Wingfield, Michael J.
    The majority of plant pathogens are fungi and many of these adversely affect food security. This minireview aims to provide an analysis of the plant pathogenic fungi for which genome sequences are publically available, to assess their general genome characteristics, and to consider how genomics has impacted plant pathology. A list of sequenced fungal species was assembled, the taxonomy of all species verified, and the potential reason for sequencing each of the species considered. The genomes of 1090 fungal species are currently (October 2016) in the public domain and this number is rapidly rising. Pathogenic species comprised the largest category (35.5 %) and, amongst these, plant pathogens are predominant. Of the 191 plant pathogenic fungal species with available genomes, 61.3 % cause diseases on food crops, more than half of which are staple crops. The genomes of plant pathogens are slightly larger than those of other fungal species sequenced to date and they contain fewer coding sequences in relation to their genome size. Both of these factors can be attributed to the expansion of repeat elements. Sequenced genomes of plant pathogens provide blueprints from which potential virulence factors were identified and from which genes associated with different pathogenic strategies could be predicted. Genome sequences have also made it possible to evaluate adaptability of pathogen genomes and genomic regions that experience selection pressures. Some genomic patterns, however, remain poorly understood and plant pathogen genomes alone are not sufficient to unravel complex pathogen-host interactions. Genomes, therefore, cannot replace experimental studies that can be complex and tedious. Ultimately, the most promising application lies in using fungal plant pathogen genomics to inform disease management and risk assessment strategies. This will ultimately minimize the risks of future disease outbreaks and assist in preparation for emerging pathogen outbreaks.