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71.
Folate salvage by Plasmodium falciparum is an important source of key cofactors, but little is known about the underlying mechanism. Using synchronised parasite cultures, we observed that uptake of this dianionic species against the negative-inward electrochemical gradient is highly dependent upon cell-cycle stage, temperature and pH, but not on mono- or divalent metal ions. Energy dependence was tested with different sugars; glucose was necessary for folate import, although fructose was also able to function in this role, unlike sugars that cannot be processed through the glycolytic pathway. Import into both infected erythrocytes and free parasites was strongly inhibited by the anion-channel blockers probenecid and furosemide, which are likely to be acting predominantly on specific folate transporters in both cases. Import was not affected by high concentrations of the antifolate drugs pyrimethamine and sulfadoxine, but was inhibited by the close folate analogue methotrexate. The pH optimum for folate uptake into infected erythrocytes was 6.5-7.0. Dinitrophenol and nigericin, which strongly facilitate the equilibration of H(+) ions across biological membranes and thus abolish or substantially reduce the proton gradient, inhibited folate uptake profoundly. The ATPase inhibitor concanamycin A also greatly reduced folate uptake, further demonstrating a link to ATP-powered proton transport. These data strongly suggest that the principal folate uptake pathway in P. falciparum is specific, highly regulated, dependent upon the proton gradient across the parasite plasma membrane, and is likely to be mediated by one or more proton symporters. 相似文献
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73.
Willie A. S. Vieira Sami J. Michereff Marcos A. de Morais Jr Kevin D. Hyde Marcos P. S. Câmara 《Fungal Diversity》2014,67(1):181-202
Endophytic species of Colletotrichum associated with Mangifera indica (mango) are poorly understood. In this study, Colletotrichum species were isolated from mango in Pernambuco State, Brazil. There were significant differences in isolation frequencies of Colletotrichum species among sites and plant tissues. Mature leaf blades were colonized by most Colletotrichum isolates at the majority of sites. Partial sequences of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of 97 Colletotrichum isolates were amplified as an initial measure of genetic diversity. Phylogenetic analysis with a subset of 22 isolates were performed based on a multi-locus dataset (ACT, TUB2, CAL, CHS-1, GAPDH, ITS) followed by Apn2/MAT IGS sequence-analysis for isolates within the C. gloeosporioides species complex. Molecular analysis associated with phenotypic characteristics revealed six previously described species [C. asianum, C. cliviae, C. dianesei (syn. C. melanocaulon), C. fructicola, C. karstii and C. tropicale] and one new species. This new species is introduced as C. endomangiferae. All species isolated were pathogenic on mango fruits but varied in their virulence. There was no distribution pattern of species among sites and plant tissues, although C. asianum was the most prevalent species at all sites and in all plant tissues studied. Five previously reported Colletotrichum species causing anthracnose in mango fruits in northeastern Brazil were also recovered as endophytes. 相似文献
74.
Kasun M. Thambugala Hiran A. Ariyawansa Yan-Mei Li Saranyaphat Boonmee Sinang Hongsanan Qing Tian Chonticha Singtripop D. Jayarama Bhat Erio Camporesi Ruvishika Jayawardena Zuo-Yi Liu Jian-Chu Xu Ekachai Chukeatirote Kevin D. Hyde 《Fungal Diversity》2014,68(1):105-158
The type specimens or representative specimens of the potentially dothidealean genera Bagnisiella, Botryochora, Coccostromella, Columnosphaeria, Delphinella, Dictyodothis, Discosphaerina, Dothidea, Dothiora, Endodothiora, Jaffuela, Mycoporis, Omphalospora, Pachysacca, Plowrightia, Saccothecium, Stylodothis, Sydowia and Yoshinagaia were examined while, fresh specimens of Aureobasidium pullulans, Dothidea insculpta, Plowrightia ribesia and Saccothecium sepincola were made from Italy and Thailand. An introduction and the history of these genera, their family placement, morphology, and molecular phylogeny are provided. Morphology plus GenBank data are used to provide a systematic treatment of Dothideales. Phylogenetic analysis of LSU, SSU and ITS gene regions was carried out and in the resulting phylogenetic tree the taxa cluster in two clades with high bootstrap support. Clade A comprises Dothideaceae, the family type of Dothideales. The family Dothioraceae is not recognized as a distinct family and is synonymized under Dothideaceae. Neocylindroseptoria is introduced to accommodate Cylindroseptoria pistaciae as it forms a well-supported distinct clade in Dothideaceae. Clade B comprises Aureobasidium, Kabatiella, Pseudoseptoria, Saccothecium and Selenophoma species and Columnosphaeria fagi, for which we propose a new family, Aureobasidiaceae. The recently introduced Sydowia eucalypti also clustered within Clade B and therefore based on morphology and molecular phylogeny a new genus Pseudosydowia is introduced for Sydowia eucalypti. Celosporium laricicola is separated in a distinct clade, and therefore it is placed in Dothideales, genera, incertae sedis. The genera Bagnisiella, Botryochora, Coccostromella, Jaffuela, Lucidascocarpa, Mycoporis, Omphalospora, Pachysacca and Yoshinagaia are excluded from Dothideales and their placements are discussed. 相似文献
75.
Putarak Chomnunti Sinang Hongsanan Begoña Aguirre-Hudson Qing Tian Derek Peršoh Manpreet K. Dhami Aisyah S. Alias Jianchu Xu Xingzhong Liu Marc Stadler Kevin D. Hyde 《Fungal Diversity》2014,66(1):1-36
Sooty moulds are a remarkable, but poorly understood group of fungi. They coat fruits and leaves superficially with black mycelia, which reduces photosynthesis rates of host plants. Few researchers have, however, tried to quantify their economic importance. Sooty moulds have been well-studied at the morphological level, but they are poorly represented in a natural classification based on phylogeny. Representatives are presently known in Antennulariellaceae, Capnodiaceae, Chaetothyriaceae, Coccodiniaceae, Euantennariaceae, Metacapnodiaceae and Trichomeriaceae and several miscellaneous genera. However, molecular data is available for only five families. Most sooty mould colonies comprise numerous species and thus it is hard to confirm relationships between genera or sexual and asexual states. Future studies need to obtain single spore isolates of species to test their phylogenetic affinities and linkages between morphs. Next generation sequencing has shown sooty mould colonies to contain many more fungal species than expected, but it is not clear which species are dominant or active in the communities. They are more common in tropical, subtropical and warm temperate regions and thus their prevalence in temperate regions is likely to increase with global warming. Sooty moulds are rarely parasitized by fungicolous taxa and these may have biocontrol potential. They apparently grow in extreme environments and may be xerophilic. This needs testing as xerophilic taxa may be of interest for industrial applications. Sooty moulds grow on sugars and appear to out-compete typical “weed” fungi and bacteria. They may produce antibiotics for this purpose and their biochemical potential for obtaining novel bioactive compounds for medical application is underexplored. 相似文献
76.
Ali A. Alsaad MD Hyde M. Russell MD Arthur J. Tokarczyk MD Mark J. Ricciardi MD 《Catheterization and cardiovascular interventions》2021,97(5):E731-E735
Postinfarction ventricular septal rupture is a rare and devastating complication of myocardial infarction. Despite attempts at acute surgical and percutaneous defect closure, morbidity and mortality remain high. Herein, we describe a hybrid surgical and catheter-based approach to defect closure in a 63-year-old woman with postinfarction ventricular septal rupture and cardiogenic shock. 相似文献
77.
78.
A comparative analysis of transcribed genes in the mouse hypothalamus and neocortex reveals chromosomal clustering
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79.
80.
T.P. Hyde H.L. Craddock J.C. Gray S.H. Pavitt C. Hulme M. Godfrey C. Fernandez N. Navarro-Coy S. Dillon J. Wright S. Brown G. Dukanovic P.A. Brunton 《Journal of dentistry》2014