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Fulltext Draft genome sequence of Daldinia eschscholzii isolated from blood culture

Ng KP, Ngeow YF, Yew SM, Hassan H, Soo-Hoo TS, Na SL, et al.

Eukaryot Cell, 2012 May;11(5):703-4.
PMID: 22544898 DOI: 10.1128/EC.00074-12

Daldinia eschscholzii is an invasive endophyte that is most commonly found in plant tissues rich in secondary metabolites. We report the draft genome sequence of D. eschscholzii isolated from blood culture. The draft genome is 35,494,957 bp in length, with 42,898,665 reads, 61,449 contigs, and a G+C content of 46.8%. The genome was found to contain a high abundance of genes associated with plant cell wall degradation enzymes, mycotoxin production, and antifungal drug resistance.

Matched MeSH terms: Ascomycota/genetics*; Ascomycota/isolation & purification
Morphological and molecular characterization, sexual reproduction, and pathogenicity of Setosphaeria rostrata isolates from rice leaf spot

Kusai NA, Azmi MM, Zainudin NA, Yusof MT, Razak AA

Mycologia, 2016 09;108(5):905-914.
PMID: 27474518

Setosphaeria rostrata, a common plant pathogen causing leaf spot disease, affects a wide range of plant species, mainly grasses. Fungi were isolated from brown spots on rice leaves throughout Peninsular Malaysia, and 45 isolates were identified as Setosphaeria rostrata The isolates were then characterized using morphological and molecular approaches. The mating type was determined using PCR amplification of the mating type alleles, and isolates of opposite mating types were crossed to examine sexual reproduction. Based on nuclear ribosomal DNA ITS1-5.8S-ITS2 region (ITS) and beta-tubulin (BT2) sequences, two phylogenetic trees were constructed using the maximum likelihood method; S. rostrata was clustered in one well-supported clade. Pathogenicity tests showed that S. rostrata isolates are pathogenic, suggesting that it is the cause of the symptoms. Mating-type analyses indicated that three isolates carried the MAT1-1 allele, and the other 42 isolates carried MAT1-2 After isolates with opposite mating types were crossed on Sach's medium and incubated for 3 wk, six crosses produced pseudothecia that contained eight mature ascospores, and 12 other crosses produced numerous pseudothecia with no ascospores. To our knowledge, this is the first report on S. rostrata isolated from leaf spots on rice.

Matched MeSH terms: Ascomycota/classification*; Ascomycota/cytology; Ascomycota/genetics; Ascomycota/isolation & purification*
Molecular diversity of fungal endophytes isolated from Garcinia mangostana and Garcinia parvifolia

Sim JH, Khoo CH, Lee LH, Cheah YK

J Microbiol Biotechnol, 2010 Apr;20(4):651-8.
PMID: 20467234

Garcinia is commonly found in Malaysia, but limited information is available regarding endophytic fungi associated with this plant. In this study, 24 endophytic fungi were successfully recovered from different parts of two Garcinia species. Characterization of endophytic fungi was performed based on the conserved internal transcribed spacer (ITS) region sequence analysis and the antimicrobial properties. Results revealed that fruits of the plant appeared to be the highest inhabitation site (38 %) as compared with others. Glomerella sp., Guignardia sp., and Phomopsis sp. appeared to be the predominant endophytic fungi group in Garcinia mangostana and Garcinia parvifolia. Phylogenetic relationships of the isolated endophytic fungi were estimated from the sequences of the ITS region. On the other hand, antibacterial screening showed 11 of the isolates possessed positive response towards pathogenic and nonpathogenic bacteria. However, there was no direct association between certain antibacterial properties with the specific genus observed.

Matched MeSH terms: Ascomycota/genetics*; Ascomycota/isolation & purification
Decolorization of palm oil mill effluent using growing cultures of Curvularia clavata

Neoh CH, Lam CY, Lim CK, Yahya A, Ibrahim Z

Environ Sci Pollut Res Int, 2014 Mar;21(6):4397-408.
PMID: 24327114 DOI: 10.1007/s11356-013-2350-1

Agricultural wastewater that produces color are of environmental and health concern as colored effluent can produce toxic and carcinogenic by-products. From this study, batch culture optimization using response surface methods indicated that the fungus isolated from the pineapple solid waste, Curvularia clavata was able to decolorize sterile palm oil mill effluent (POME) which is mainly associated with polyphenol and lignin. Results showed successful decolorization of POME up to 80 % (initial ADMI [American Dye Manufacturing Index] of 3,793) with 54 % contributed by biosorption and 46 % by biodegradation after 5 days of treatment. Analysis using HPLC and GC-MS showed the degradation of color causing compound such as 3-methoxyphenyl isothiocynate and the production of new metabolites. Ecotoxicity test indicated that the decolorized effluent is safe for discharge. To determine the longevity of the fungus for a prolonged decolorization period, sequential batch decolorization studies were carried out. The results showed that lignin peroxidase and laccase were the main ligninolytic enzymes involved in the degradation of color. Carboxymethyl cellulase (CMCase) and xylanase activities were also detected suggesting possible roles of the enzymes in promoting growth of the fungus which consequently contributed to improved decolorization of POME. In conclusion, the ability of C. clavata in treating color of POME indicated that C. clavata is of potential use for decolorization and degradation of agricultural wastewater containing polyphenolic compounds.

Matched MeSH terms: Ascomycota/metabolism; Ascomycota/physiology*
Fulltext Genome-Wide Detection of Genes Under Positive Selection in Worldwide Populations of the Barley Scald Pathogen

Mohd-Assaad N, McDonald BA, Croll D

Genome Biol Evol, 2018 Apr 01;10(5):1315-1332.
PMID: 29722810 DOI: 10.1093/gbe/evy087

Coevolution between hosts and pathogens generates strong selection pressures to maintain resistance and infectivity, respectively. Genomes of plant pathogens often encode major effect loci for the ability to successfully infect specific host genotypes. Hence, spatial heterogeneity in host genotypes coupled with abiotic factors could lead to locally adapted pathogen populations. However, the genetic basis of local adaptation is poorly understood. Rhynchosporium commune, the pathogen causing barley scald disease, interacts at least partially in a gene-for-gene manner with its host. We analyzed global field populations of 125 R. commune isolates to identify candidate genes for local adaptation. Whole genome sequencing data showed that the pathogen is subdivided into three genetic clusters associated with distinct geographic and climatic regions. Using haplotype-based selection scans applied independently to each genetic cluster, we found strong evidence for selective sweeps throughout the genome. Comparisons of loci under selection among clusters revealed little overlap, suggesting that ecological differences associated with each cluster led to variable selection regimes. The strongest signals of selection were found predominantly in the two clusters composed of isolates from Central Europe and Ethiopia. The strongest selective sweep regions encoded protein functions related to biotic and abiotic stress responses. Selective sweep regions were enriched in genes encoding functions in cellular localization, protein transport activity, and DNA damage responses. In contrast to the prevailing view that a small number of gene-for-gene interactions govern plant pathogen evolution, our analyses suggest that the evolutionary trajectory is largely determined by spatially heterogeneous biotic and abiotic selection pressures.

Matched MeSH terms: Ascomycota/genetics*; Ascomycota/isolation & purification
Fulltext Draft Genome Sequence of Dematiaceous Coelomycete Pyrenochaeta sp. Strain UM 256, Isolated from Skin Scraping

Yew SM, Chan CL, Soo-Hoo TS, Na SL, Ong SS, Hassan H, et al.

Genome Announc, 2013;1(3).
PMID: 23723391 DOI: 10.1128/genomeA.00158-13

Pyrenochaeta, classified under the order Pleosporales, is known to cause diseases in plants and humans. Here, we report a draft genome sequence of a Pyrenochaeta sp. isolated from a skin scraping, with an estimated genome size of 39.4 Mb. Genes associated with the synthesis of proteases, toxins, plant cell wall degradation, and multidrug resistance were found.

Matched MeSH terms: Ascomycota
Management of collar rot disease in chili by farmyard manure and commercial biofertilizers

Amna Shoaib, Arshad Javaid, Nighat Sana

Sains Malaysiana, 2017;46:1693-1700.

Collar rot of chili (Capsicum annuum L.) is a very destructive disease caused by a soil-borne fungal pathogen Sclerotium rolfsii Sacc. Generally, chemical fungicides are used to combat the menace but this practice is being discouraged because of health and environmental concerns. In the present study, an alternative environment friendly strategy was used to manage this disease by using farmyard manure (FYM) and two commercial biofertilizers namely Biopower and Feng Shou. S. rolfsii inoculated pot soil was amended with 1% and 2% FYM and the two commercial biofertilizers. Inoculation of soil with S. rolfsii only (positive control) resulted in the highest disease incidence (73%) and plant mortality (60%). Biopower and Feng Shou application reduced disease incidence to 20% and 7%, respectively and plant mortality to 0%. Likewise, 1% and 2% FYM amendment reduced disease incidence to 33% and plant mortality to 26% and 7%, respectively. Under biotic stress of S. rolfsii, FYM and biofertilizers applications, either alone or in combination, significantly enhanced root and shoot growth over positive control. S. rolfsii inoculation significantly increased peroxidase and polyphenol oxidase activities in chili plants which were further increased by application of either of the two biofertilizers. The present study concludes that biofertilizers Biopower and Feng Shou alone or in combination with 2% FYM can be effectively utilized to manage southern blight of chili.

Matched MeSH terms: Ascomycota
Fulltext Cross-amplification of microsatellite markers across agarwood-producing species of the Aquilarieae tribe (Thymelaeaceae)

Pern YC, Lee SY, Ng WL, Mohamed R

3 Biotech, 2020 Mar;10(3):103.
PMID: 32099744 DOI: 10.1007/s13205-020-2072-2

Tree species in the Aquilarieae tribe of the Thymelaeaceae family produce agarwood, a natural product highly valued for its fragrance, but the species are under threat due to indiscriminate harvesting. For conservation of these species, molecular techniques such as DNA profiling have been used. In this study, we assessed cross-amplification of microsatellite markers, initially developed for three Aquilaria species (A.crassna, A.malaccensis, and A.sinensis), on ten other agarwood-producing species, including members of Aquilaria (A.beccariana, A.hirta, A.microcarpa, A.rostrata, A.rugosa, A.subintegra, and A.yunnanensis) and Gyrinops (G.caudata, G.versteegii, and G.walla), both from the Aquilarieae tribe. Primers for 18 out of the 30 microsatellite markers successfully amplified bands of expected sizes in 1 sample each of at least 10 species. These were further used to genotype 74 individuals representing all the 13 studied species, yielding 13 cross-amplifiable markers, of which only 1 being polymorphic across all species. At each locus, the number of alleles ranged from 7 to 23, indicating a rather high variability. Four markers had relatively high species discrimination power. Our results demonstrated that genetic fingerprinting can be an effective tool in helping to manage agarwood genetic resources by potentially supporting the chain-of-custody of agarwood and its products in the market.

Matched MeSH terms: Ascomycota
Fulltext A case report of Intramuscular Abscess Secondary to Epicoccum Nigrum infection

Azira NMS, Zeehaida M, Nazli Z, Suraiya S

Journal of Clinical and Health Sciences, 2016;1:48-51.

A 36-year-old man with underlying chronic lymphocytic leukemia had left arm swelling for a duration of 3 months. Clinically, the affected arm was swollen, erythematous and tender. Epicoccum nigrum was isolated from the culture of the tissue that was obtained intraoperatively. He was treated and responded to voriconazole therapy. To the best of our knowledge, this is the first case of intramuscular abscess as a result of E. nigrum infection in an immunocompromised patient.

Matched MeSH terms: Ascomycota
Fulltext Fatty Acid Synthase Beta Dehydratase in the Lipid Biosynthesis Pathway Is Required for Conidiogenesis, Pigmentation and Appressorium Formation in Magnaporthe oryzae S6

Sangappillai V, Nadarajah K

Int J Mol Sci, 2020 Sep 30;21(19).
PMID: 33007862 DOI: 10.3390/ijms21197224

Lipid biosynthesis produces glycerol, which is important in fueling turgor pressure necessary for germination and penetration of plant host by fungi. As the relationship between pathogenicity and the lipid biosynthetic pathway is not fully understood, we have elucidated the role of the fatty acid synthase beta subunit dehydratase (FAS1) gene in lipid biosynthesis. The FAS1 gene was silenced through homologous double crossover in Magnaporthe oryzae strain S6 to study the effect on lipid biosynthesis. The vegetative growth of Δfas1 mutants show the highest drop on oleic acid (between 10 and 50%), while the mycelial dry weight of mutants dropped significantly on all media. Conidiation of FAS1 mutants show a ~10- and ~5-fold reduction on oatmeal and Potato Dextrose Agar (PDA), respectively. Mutants formed mycelium that were mildly pigmented, indicating that the deletion of FAS1 may have affected melanin biosynthesis. Biochemical and gene expression studies concluded that the fatty acid degradation pathway might have been interrupted by FAS1 deletion. FAS1 mutants showed no enzyme activity on glucose or olive oil, suggesting that the mutants may lack functional peroxisomes and be defective in β-oxidation of fatty acids, hence explaining the reduced lipid deposits in the spores.

Matched MeSH terms: Ascomycota/genetics*; Ascomycota/growth & development; Ascomycota/pathogenicity
Fulltext Functional expression of a novel α-amylase from Antarctic psychrotolerant fungus for baking industry and its magnetic immobilization

He L, Mao Y, Zhang L, Wang H, Alias SA, Gao B, et al.

BMC Biotechnol, 2017 02 28;17(1):22.
PMID: 28245836 DOI: 10.1186/s12896-017-0343-8

BACKGROUND: α-Amylase plays a pivotal role in a broad range of industrial processes. To meet increasing demands of biocatalytic tasks, considerable efforts have been made to isolate enzymes produced by extremophiles. However, the relevant data of α-amylases from cold-adapted fungi are still insufficient. In addition, bread quality presents a particular interest due to its high consummation. Thus developing amylases to improve textural properties could combine health benefits with good sensory properties. Furthermore, iron oxide nanoparticles provide an economical and convenient method for separation of biomacromolecules. In order to maximize the catalytic efficiency of α-amylase and support further applications, a comprehensive characterization of magnetic immobilization of α-amylase is crucial and needed.
RESULTS: A novel α-amylase (AmyA1) containing an open reading frame of 1482 bp was cloned from Antarctic psychrotolerant fungus G. pannorum and then expressed in the newly constructed Aspergillus oryzae system. The purified recombinant AmyA1 was approximate 52 kDa. AmyA1 was optimally active at pH 5.0 and 40 °C, and retained over 20% of maximal activity at 0-20 °C. The K m and V max values toward soluble starch were 2.51 mg/mL and 8.24 × 10-2 mg/(mL min) respectively, with specific activity of 12.8 × 103 U/mg. AmyA1 presented broad substrate specificity, and the main hydrolysis products were glucose, maltose, and maltotetraose. The influence of AmyA1 on the quality of bread was further investigated. The application study shows a 26% increase in specific volume, 14.5% increase in cohesiveness and 14.1% decrease in gumminess in comparison with the control. AmyA1 was immobilized on magnetic nanoparticles and characterized. The immobilized enzyme showed improved thermostability and enhanced pH tolerance under neutral conditions. Also, magnetically immobilized AmyA1 can be easily recovered and reused for maximum utilization.
CONCLUSIONS: A novel α-amylase (AmyA1) from Antarctic psychrotolerant fungus was cloned, heterologous expression in Aspergillus oryzae, and characterized. The detailed report of the enzymatic properties of AmyA1 gives new insights into fungal cold-adapted amylase. Application study showed potential value of AmyA1 in the food and starch fields. In addition, AmyA1 was immobilized on magnetic nanoparticles and characterized. The improved stability and longer service life of AmyA1 could potentially benefit industrial applications.

Matched MeSH terms: Ascomycota/classification; Ascomycota/enzymology*; Ascomycota/genetics
Fulltext Comparison of diversity of microfungi in ornithogenic soils from Beaufort Island, continental Antarctica and Barrientos Island, maritime Antarctica

Omar, S., Alias, S.A., Smykla, J., Moreano, H., Guerra, M.L., Ming, C.Y.

ASM Science Journal, 2009;3(2):184-194.
MyJurnal

Results of a biodiversity study of Antarctic microfungi from ornithogenic soils are presented in this paper. A wide range of soil habitats within and adjacent to active and abandoned penguin rookeries were sampled in order to examine relationships between environmental factors and the biodiversity of soil microfungi. Soil samples were collected from two contrasting Antarctic locations: (1) Beaufort Island (Ross Sea, Continental Antarctica), which is largely ice- and snow-covered, isolated, difficult to access and infrequently visited, and (2) Barrientos Island (maritime Antarctica) which is mostly ice-free during summer and is often visited by scientists and tourists. Soil sampling at Beaufort and Barrientos Islands was completed during the austral summer seasons of 2004/05 and 2006/07, respectively. Warcup’s soil method was used for fungi cultivation. A total of 27 fungal taxa were isolated from the two study sites, consisting of 11 ascomycetes, 13 hyphomycetes
and three yeasts. Only three taxa — Geomyces sp., a pink and a white yeast — occurred on both sites. The isolated fungi were classified according to their thermal characteristics in culture, with seven psychrophilic, 10 psychrotrophic and 10 mesophilic fungi being isolated. Thelebolus microspores, Thelebolus sp., Geomyces sp. and Antarctomyces sp., were the most frequently isolated fungi. A total of 10 taxa were isolated from the 20 soil samples from Beaufort Island, consisting of five psychrophilic, four psychrotrophic and one mesophilic fungi. Thelebolus microsporus, Thelebolus sp., Asco BI8 and Phoma sp. were the most frequently obtained fungi
(20%–27% of isolates). A total of 22 fungal taxa were isolated from 23 soil samples from Barrientos Island, consisting of four psychrophilic, six psychrotrophic and 12 mesophilic fungi. Geomyces sp. and Antarctomyces sp. were the most frequently isolated taxa. Thus, the fungal diversity of Beaufort Island was dominated by Ascomycetes while that of Barrientos Island was dominated by hyphomycetes.

Matched MeSH terms: Ascomycota
Distribution of Lichen Flora at Different Altitudes of Gunung Machincang, Langkawi Islands, Malaysia

Shahrizim Zulkifly, Young SK, Mohamed Abudl Majid, Amir Feisal Merican

Sains Malaysiana, 2011;40:1201-1208.

Lichen samples were collected from Gunung Machincang, Langkawi Islands based on an alternation of altitudes, which are 0, 300 and above 600 m. Morphological identification resulted in 15 genera of microlichens (crustose) and five genera of macrolichens (foliose) and they fall under 14 families. As the altitude increases, the number of foliose type of lichen also increased. The common microlichens obtained were from the Family of Graphidaceae and can be found from the sea level right up to the peak of Gunung Machincang. The most common crustose lichens found were Heterodermia sp., while Eugenia sp. is the most common tree habitat for lichens in Gunung Machincang, Langkawi Islands. This study represents the first record of lichens in Gunung Machincang, Langkawi Islands, Malaysia.

Matched MeSH terms: Ascomycota
First Report of Dolabra nepheliae on Rambutan and Litchi in Hawaii and Puerto Rico

Rossman AY, Goenaga R, Keith L

Plant Dis, 2007 Dec;91(12):1685.
PMID: 30780638 DOI: 10.1094/PDIS-91-12-1685C

A stem canker disease on rambutan (Nephelium lappaceum L.) and litchi (Litchi chinensis Sonn. (Sapindaceae) was found in plants in Hawaii and Puerto Rico. A fungus associated with cankers was identified as Dolabra nepheliae C. Booth & Ting (1). Numerous black, stipitate, elongate ascomata were produced within cracks of cankers. These ascomata contain elongate, bitunicate asci amid unbranched, interthecial elements and thin, cylindrical, hyaline ascospores measuring 96 to 136 × 2.5 to 3.5 μm. This fungus was originally described from Malaysia on N. lappaceum (1) and is also known on pulasan (N. mutabile Blume) in Australia (2). Classified by the Food and Agriculture Organization as a 'minor disease', the canker appears to be relatively common in Hawaii and was most likely introduced into Puerto Rico on imported germplasm. Nevertheless, efforts are underway to study the potential damage of this disease as well as mechanisms of control, including introduction of disease resistant clones. Specimens have been deposited at the U.S. National Fungus Collections (Hawaii on Nephelium BPI 878189, Puerto Rico (PR) on Nephelium BPI 878188, and PR on Litchi BPI 878190). Although a specimen of D. nepheliae on L. chinensis was collected from Hawaii in 1984 by G. Wong and C. Hodges and deposited as BPI 626373, this fungus was not known on Nephelium spp. in Hawaii and was not previously known from Puerto Rico on either host. References: (1) C. Booth and W. P. Ting. Trans. Brit. Mycol. Soc. 47:235, 1964. (2) T. K. Lim and Y. Diczbalis. Rambutan. Page 306 in: The New Rural Industries. Online publication. Rural Industries Research and Development Corporation, Australia, 1997.

Matched MeSH terms: Ascomycota
Fulltext A case report of Intramuscular Abscess Secondary to Epicoccum Nigrum infection

Azira NMS, Zeehaida M, Nazli Z, Suraiya S

Journal of Clinical and Health Sciences, 2016;1(2):48-51.
MyJurnal

A 36-year-old man with underlying chronic lymphocytic leukemia had left arm swelling for a duration of 3 months. Clinically, the affected arm was swollen, erythematous and tender. Epicoccum nigrum was isolated from the culture of the tissue that was obtained intraoperatively. He was treated and responded to voriconazole therapy. To the best of our knowledge, this is the first case of intramuscular abscess as a result of E. nigrum infection in an immunocompromised patient.

Matched MeSH terms: Ascomycota
Fulltext Comparative chemical screening and genetic analysis reveal tentoxin as a new virulence factor in Cochliobolus miyabeanus, the causal agent of brown spot disease on rice

De Bruyne L, Van Poucke C, Di Mavungu DJ, Zainudin NA, Vanhaecke L, De Vleesschauwer D, et al.

Mol Plant Pathol, 2016 Aug;17(6):805-17.
PMID: 26456797 DOI: 10.1111/mpp.12329

Brown spot disease, caused by Cochliobolus miyabeanus, is currently considered to be one of the most important yield reducers of rice (Oryza sativa L.). Despite its agricultural importance, little is known about the virulence mechanisms deployed by the fungus. Therefore, we set out to identify novel virulence factors with a role in disease development. This article reports, for the first time, the production of tentoxin by C. miyabeanus as a virulence factor during brown spot disease and the identification of the non-ribosomal protein synthetase (NRPS) CmNps3, responsible for tentoxin biosynthesis. We compared the chemical compounds produced by C. miyabeanus strains differing in virulence ability using ultra-high-performance liquid chromatography (UHPLC) coupled to high-resolution Orbitrap mass spectrometry (HRMS). The production of tentoxin by a highly virulent strain was revealed by principal component analysis of the detected ions and confirmed by UHPLC coupled to tandem-quadrupole mass spectrometry (MS/MS). The corresponding NRPS was identified by in silico genome analysis and confirmed by gene deletion. Infection tests with wild-type and Cmnps3 mutants showed that tentoxin acts as a virulence factor and is correlated with chlorosis development during the second phase of infection. Although rice has previously been classified as a tentoxin-insensitive plant species, our data demonstrate that tentoxin production by C. miyabeanus affects symptom development.

Matched MeSH terms: Ascomycota/genetics*; Ascomycota/growth & development; Ascomycota/pathogenicity
An antibacterial metabolite from Lasiodiplodia pseudotheobromae F2

Wei W, Jiang N, Mei YN, Chu YL, Ge HM, Song YC, et al.

Phytochemistry, 2014 Apr;100:103-9.
PMID: 24529576 DOI: 10.1016/j.phytochem.2014.01.003

In searching for symbionts derived from bioactive natural products, six sulfureous diketopiperazines designated as lasiodiplines A-F (1-6) were characterized from the culture of Lasiodiplodia pseudotheobromae F2, previously residing in the apparently normal flower of Illigera rhodantha (Hernandiaceae). Identification of structures was accomplished by a combination of spectroscopic and computational approaches, in conjunction with the low-temperature (100K) single-crystal X-ray diffraction with Cu Kα radiation. Lasiodipline E (5) was demonstrated to be antibacterial against the clinical strains Streptococcus sp., Bacteroides vulgates, Peptostreptococcus sp. and Veillonella parvula, respectively, with an minimum inhibitory concentration (MIC) range of 0.12-0.25 μg/mL. In addition, compounds 4 and 6 exemplify two unusual architectures of natural cyclodipeptides, signifying the unique biochemical characteristics of the producing fungus.

Matched MeSH terms: Ascomycota/metabolism*
Fulltext Chromoblastomycosis

Yap FB

Int J Infect Dis, 2010 Jun;14(6):e543-4.
PMID: 19889559 DOI: 10.1016/j.ijid.2009.07.005
Matched MeSH terms: Ascomycota/isolation & purification*
Enzymatic synthesis of 6-O-glucosyl-poly(3-hydroxyalkanoate) in organic solvents and their binary mixture

Gumel AM, Annuar MS, Heidelberg T

Int J Biol Macromol, 2013 Apr;55:127-36.
PMID: 23305702 DOI: 10.1016/j.ijbiomac.2012.12.028

The effects of organic solvents and their binary mixture in the glucose functionalization of bacterial poly-3-hydroxyalkanoates catalyzed by Lecitase™ Ultra were studied. Equal volume binary mixture of DMSO and chloroform with moderate polarity was more effective for the enzyme catalyzed synthesis of the carbohydrate polymer at ≈38.2 (±0.8)% reactant conversion as compared to the mono-phasic and other binary solvents studied. The apparent reaction rate constant as a function of medium water activity (aw) was observed to increase with increasing solvent polarity, with optimum aw of 0.2, 0.4 and 0.7 (±0.1) observed in hydrophilic DMSO, binary mixture DMSO:isooctane and hydrophobic isooctane, respectively. Molecular sieve loading between 13 to 15gL(-1) (±0.2) and reaction temperature between 40 to 50°C were found optimal. Functionalized PHA polymer showed potential characteristics and biodegradability.

Matched MeSH terms: Ascomycota/metabolism*
Meroterpenes with toll-like receptor 3 regulating activity from the endophytic fungus Guignardia mangiferae

Han WB, Dou H, Yuan WH, Gong W, Hou YY, Ng SW, et al.

Planta Med, 2015 Jan;81(2):145-51.
PMID: 25519918 DOI: 10.1055/s-0034-1383392

The endophytic fungus Guignardia mangiferae isolated from Ilex cornuta leaves was shown to produce a family of meroterpenes with toll-like receptor 3 regulating activity (1-9), of which 1-3 possessed new structures. The absolute stereochemistry of 1-3 was assigned through a combination of nuclear magnetic resonance experiments, chemical derivation, CD spectra, and single-crystal X-ray diffraction analyses (CuK α ). The precursor labeled cultivation suggests that these meroterpenes are most likely assembled through terpenoid-shikimate pathways. Moreover, meroterpenes 1-3, 5-7, and 9 selectively upregulate, but 4 and 8 downregulate the toll-like receptor 3 expression in mouse dendritic cells at 10.0 µM.

Matched MeSH terms: Ascomycota/chemistry*

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