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1.
Int J Hyperthermia ; 33(3): 255-262, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27817240

RESUMO

PURPOSE: The aim of this study was to compare the results of microwave ablation (MWA) and hepatic resection (HR) when combined with pericardial devascularisation plus splenectomy (PCDV) for the treatment of patients with cirrhosis complicated by small hepatocellular carcinoma (HCC) and oesophageal variceal bleeding (EVB). MATERIALS AND METHODS: Between 2001 and 2013, 73 patients (median age 53.2 years, 67% male) with small HCC and concomitant EVB who underwent MWA or HR for HCC and PCDV for cirrhotic portal hypertension were selected retrospectively for inclusion in this study. The overall survival curves and recurrence-free survival curves were calculated using the Kaplan-Meier method and compared using log-rank tests. Multivariate analysis was performed using the Cox regression model. RESULTS: The 1-, 3- and 5-year overall survival rates were 95.2%, 71.4% and 38.1% and 96.7%, 53.3% and 43.3% for the HR and MWA groups, respectively; these did not differ significantly between the two groups. However, patients in the HR group had more post-operative complications (52.3% vs. 13.7%; p = 0.002). Multivariate analysis identified albumin and bilirubin levels and tumour size to be statistically significant and independent prognostic factors for overall survival, while BCLC stage was associated with poor recurrence-free survival. Furthermore, albumin levels were shown to be an independent predictive factor for post-operative complications. CONCLUSIONS: For patients with small HCC and concomitant EVB, MWA plus PCDV may reduce the incidence of post-operative complications relative to and provide similar therapeutic benefits as HR plus PCDV, especially for patients with low albumin levels.

2.
PLoS Genet ; 8(5): e1002703, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22589740

RESUMO

The apple is the most common and culturally important fruit crop of temperate areas. The elucidation of its origin and domestication history is therefore of great interest. The wild Central Asian species Malus sieversii has previously been identified as the main contributor to the genome of the cultivated apple (Malus domestica), on the basis of morphological, molecular, and historical evidence. The possible contribution of other wild species present along the Silk Route running from Asia to Western Europe remains a matter of debate, particularly with respect to the contribution of the European wild apple. We used microsatellite markers and an unprecedented large sampling of five Malus species throughout Eurasia (839 accessions from China to Spain) to show that multiple species have contributed to the genetic makeup of domesticated apples. The wild European crabapple M. sylvestris, in particular, was a major secondary contributor. Bidirectional gene flow between the domesticated apple and the European crabapple resulted in the current M. domestica being genetically more closely related to this species than to its Central Asian progenitor, M. sieversii. We found no evidence of a domestication bottleneck or clonal population structure in apples, despite the use of vegetative propagation by grafting. We show that the evolution of domesticated apples occurred over a long time period and involved more than one wild species. Our results support the view that self-incompatibility, a long lifespan, and cultural practices such as selection from open-pollinated seeds have facilitated introgression from wild relatives and the maintenance of genetic variation during domestication. This combination of processes may account for the diversification of several long-lived perennial crops, yielding domestication patterns different from those observed for annual species.


Assuntos
Cruzamento , Fluxo Gênico , Variação Genética , Malus , Filogeografia , Ásia , China , Europa (Continente) , Evolução Molecular , Frutas/genética , Genoma de Planta , Malus/genética , Repetições de Microssatélites , Espanha
3.
BMC Plant Biol ; 14: 126, 2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24886309

RESUMO

BACKGROUND: Effector proteins function not only as toxins to induce plant cell death, but also enable pathogens to suppress or evade plant defense responses. NLP-like proteins are considered to be effector proteins, and they have been isolated from bacteria, fungi, and oomycete plant pathogens. There is increasing evidence that NLPs have the ability to induce cell death and ethylene accumulation in plants. RESULTS: We evaluated the expression patterns of 11 targeted PcNLP genes by qRT-PCR at different time points after infection by P. capsici. Several PcNLP genes were strongly expressed at the early stages in the infection process, but the expression of other PcNLP genes gradually increased to a maximum at late stages of infection. The genes PcNLP2, PcNLP6 and PcNLP14 showed the highest expression levels during infection by P. capsici. The necrosis-inducing activity of all targeted PcNLP genes was evaluated using heterologous expression by PVX agroinfection of Capsicum annuum and Nicotiana benthamiana and by Western blot analysis. The members of the PcNLP family can induce chlorosis or necrosis during infection of pepper and tobacco leaves, but the chlorotic or necrotic response caused by PcNLP genes was stronger in pepper leaves than in tobacco leaves. Moreover, PcNLP2, PcNLP6, and PcNLP14 caused the largest chlorotic or necrotic areas in both host plants, indicating that these three genes contribute to strong virulence during infection by P. capsici. This was confirmed through functional evaluation of their silenced transformants. In addition, we further verified that four conserved residues are putatively active sites in PcNLP1 by site-directed mutagenesis. CONCLUSIONS: Each targeted PcNLP gene affects cells or tissues differently depending upon the stage of infection. Most PcNLP genes could trigger necrotic or chlorotic responses when expressed in the host C. annuum and the non-host N. benthamiana. Individual PcNLP genes have different phytotoxic effects, and PcNLP2, PcNLP6, and PcNLP14 may play important roles in symptom development and may be crucial for virulence, necrosis-inducing activity, or cell death during infection by P. capsici.


Assuntos
Phytophthora/metabolismo , Phytophthora/fisiologia , Doenças das Plantas/microbiologia , Proteínas/metabolismo , Agrobacterium/metabolismo , Capsicum/genética , Capsicum/microbiologia , Regulação da Expressão Gênica de Plantas , Vetores Genéticos , Mutagênese Sítio-Dirigida , Mutação/genética , Necrose , Phytophthora/patogenicidade , Doenças das Plantas/genética , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Nicotiana/microbiologia , Transformação Genética , Virulência
4.
Mycologia ; 106(4): 649-65, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24891417

RESUMO

The genus Ulocladium is thought to be strictly asexual. Mating-type (MAT) loci regulate sexual reproduction in fungi and their study may help to explain the apparent lack of sexual reproduction in Ulocladium. We sequenced the full length of two MAT genes in 26 Ulocladium species and characterized the entire MAT idiomorphs plus flanking regions of Ulocladium botrytis. The MAT1-1 ORF encodes a protein with an alpha-box motif by the MAT1-1-1 gene and the MAT1-2 ORF encodes a protein with an HMG box motif by the MAT1-2-1 gene. Both MAT1-1-1 and MAT1-2-1 genes were detected in a single strain of every species. Moreover, the results of RT-PCR revealed that both MAT genes are expressed in all 26 Ulocladium species. This demonstrates that MAT genes of Ulocladium species might be functional and that they have the potential for sexual reproduction. Phylogenies based on MAT genes were compared with GAPDH and Alt a 1 phylograms in Ulocladium using maximum parsimony (MP) and Bayesian analysis. The MAT genealogies and the non-MAT trees displayed different topologies, indicating that MAT genes are unsuitable phylogenetic markers at the species level in Ulocladium. Furthermore, the conflicting topologies between MAT1-1-1 and MAT1-2-1 phylogeny indicate separate evolutionary events for the two MAT genes. However, the intergeneric phylogeny of four closely allied genera (Ulocladium, Alternaria, Cochliobolus, Stemphylium) based on MAT alignments demonstrated that MAT genes are suitable for phylogenetic analysis among allied genera.


Assuntos
Ascomicetos/genética , Genes Fúngicos Tipo Acasalamento/genética , Sequência de Aminoácidos , Sequência de Bases , DNA Fúngico/química , DNA Fúngico/genética , Proteínas Fúngicas/genética , Loci Gênicos/genética , Domínios HMG-Box , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA
5.
Adv Mater ; : e2409839, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39279547

RESUMO

Multiscale particle size functional pesticide carriers can provide more efficient protection for plants, but this protection is difficult to achieve via single-scale formulation technology. This study presents a novel one-step method for the preparation of lignin-based micro/nanocapsules with controllable proportions within a unified system. This strategy enables the adjustment of the proportion of nanocapsules to between 18.81% and 85.21%. The microcapsules (MCs) vary in diameter from 2 to 3 µm, whereas the nanocapsules (NCs) span from 160 to 220 nm, with an encapsulation efficiency exceeding 90%. An increased proportion of NCs in the system leads to faster release, heightened sensitivity to UV light, and enhanced penetration into the leaves. During Phytophthora capsici (P. capsici) infection, the NCs in the leaves interact with the defensive enzymes of the plant to quickly respond. Moreover, an optimal balance of MCs and NCs is key to effective fungicide use, not just a higher concentration of NCs. A 65:35 ratio of NCs to MCs ensures effective inhibition of P. capsici outside leaves and a rapid response to leaf invasion. This study enhances fungicide efficiency and advances the development of nanoresponsive fungicides to promote sustainable agricultural practices.

6.
MycoKeys ; 106: 303-325, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38993357

RESUMO

Species of the family Microdochiaceae (Xylariales, Sordariomycetes) have been reported from worldwide, and collected from different plant hosts. The proposed new genus and two new species, viz., Macroidriella gen. nov., M.bambusae sp. nov. and Microdochiumaustrale sp. nov., are based on multi-locus phylogenies from a combined dataset of ITS rDNA, LSU, RPB2 and TUB2 with morphological characteristics. Microdochiumsinense has been collected from diseased leaves of Phragmitesaustralis and this is the first report of the fungus on this host plant. Simultaneously, we annotated 10,372 to 11,863 genes, identified 4,909 single-copy orthologous genes, and conducted phylogenomic analysis based on genomic data. A gene family analysis was performed and it will expand the understanding of the evolutionary history and biodiversity of the Microdochiaceae. The detailed descriptions and illustrations of species are provided.

7.
Microbiol Spectr ; 11(6): e0246823, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37905843

RESUMO

IMPORTANCE: Distoseptispora as a single genus in Distoseptisporaceae was introduced by morphological and phylogenetic analyses. Members of this genus occur mainly as asexual morphs, forming effuse, hairy colonies on decaying wood, plant stems, bamboo culms, and fallen leaves and shafts in terrestrial and freshwater habitats. In the present study, saprobic hyphomycetes from plant debris were investigated, and eight new Distoseptispora species were introduced based on morphology and phylogenetic analyses of LSU, ITS, TEF1, and RPB2 sequence data. This study provides important data on the species diversity, ecological environment, and geographical area of Distoseptispora, greatly updates the classification of Distoseptispora, and improves our understanding of the taxonomy of Distoseptispora.


Assuntos
Ascomicetos , Filogenia , China , Meio Ambiente , Água Doce
8.
J Fungi (Basel) ; 9(12)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38132783

RESUMO

The genus Gongronella is important in agriculture and industry by secreting various natural bioactive metabolites such as chitosanases and organic acids. During the most recent 8 years, a total of 14 new species have been described, remarkably enriching the diversity of this genus. In this study, we added three more new species to this valuable genus, based on a combination of morphological traits and phylogenetic information. Six strains of the genus Gongronella were isolated from soil collected in Hainan Province, China. Phylogenetic analyses of ITS and LSU rDNA sequences grouped these strains into three independent clades. According to their unique morphological characteristics, they were classified as G. multiramosa sp. nov., G. qichaensis sp. nov. and G. oleae sp. nov. The G. multiramosa was characterized by multiple branched sporangiophores and was closely related to G. pedratalhadensis. The G. qichaensis was characterized by obscure collars and closely related to G. butleri, G. hydei and G. banzhaoae. The G. oleae was characterized by the presence of oil droplets in the sporangiospores and was closely related to G. chlamydospora and G. multispora. Their descriptions and illustrations were provided, and their differences from morphological allies and phylogenetic-related species are discussed.

9.
Mycologia ; 103(2): 407-10, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20943523

RESUMO

Lomaantha phragmitis sp. nov. is described and illustrated from a specimen collected on dead culms of Phragmites communis in southern China. The fungus differs from other described Lomaantha species in its conidiophores, conidiogenous cells and conidial appendages. Conidial morphology and presence or absence of percurrent proliferation of conidiogenous cells are the main characters distinguishing species within this genus. We provided a key and synoptic table of morphological characters of all three Lomaantha species.


Assuntos
Fungos/classificação , Fungos/isolamento & purificação , Poaceae/microbiologia , China , Fungos/genética , Fungos/crescimento & desenvolvimento , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação
10.
Zhonghua Yi Xue Za Zhi ; 91(8): 532-4, 2011 Mar 01.
Artigo em Zh | MEDLINE | ID: mdl-21418854

RESUMO

OBJECTIVE: To investigate the surgical treatment of initially unresectable primary and secondary hepatic tumors. METHODS: For the patients with multiple and bilobar colonic hepatic metastases, a first-stage hepatectomy consisted in a radical resection of sigmoid colonic carcinoma and left lateral hepatic segment. Subsequently, under the guidance of ultrasonography and radiography, a right portal vein chemoembolization (PVCE) was performed via a percutaneous approach through left portal branch to induce the atrophy of right hemiliver and hypertrophy of left hemiliver. At Week 5 post-PVCE, a second-stage hepatectomy was planned to resect the right hemiliver. For patients with huge hepatocellular carcinoma (HCC), transcatheter arterial chemoembolization (TACE) were performed and it was followed by PVCE 1 week later. At Week 4 post-PVCE, a right trisegmentectomy was attempted to resect the right liver tumor. The volume of liver was evaluated with three-dimensional CT scan at Weeks 2 and 4 weeks post-PVCE. RESULTS: At Week 4 post-PVCE, the atrophy of right lobe was induced and the left lobe underwent compensatory hypertrophy. The remnant volumes of right lobe and right trisegmentectomy for HCC decreased from 1380.0 cm(3), 1685.4 cm(3) at pre-PVCE to 740.2 cm(3), 1228.1 cm(3) at post-PVCE. The values increased from pre-PVCE 435.1 cm(3), 151.5 cm(3) to post-PVCE 624.4 cm(3), 560.2 cm(3) for left hepatic lobe remnant of colonic liver metastases and left lateral segment for HCC. The ratios of liver remnant to estimated total liver volume increased from 25.6%, 13.6% at pre-PVCE to 50.0%, 43.1% post-PVCE respectively. The postoperative course was uneventful. The liver function, serum CEA and AFP decreased to the normal levels. Two patients were followed up for 18 and 8 months respectively. There was no tumor recurrence. CONCLUSION: PVCE prevents the hepatic function failure after a major hepatectomy. And it may benefit more patients with previously unresectable liver tumors.


Assuntos
Carcinoma Hepatocelular/cirurgia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/cirurgia , Adulto , Feminino , Hepatectomia/métodos , Humanos , Masculino , Veia Porta
11.
Mol Ecol ; 19(4): 658-74, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20088887

RESUMO

Evaluating the impact of plant domestication on the population structure of the associated pathogens provides an opportunity to increase our understanding of how and why diseases emerge. Here, we investigated the evolution of the population structure of the apple scab fungus Venturia inaequalis in response to the domestication of its host. Inferences were drawn from multilocus microsatellite data obtained from samples collected on (i) the Central Asian Malus sieversii, the main progenitor of apple, (ii) the European crabapple, Malus sylvestris, a secondary progenitor of apple, and (iii) the cultivated apple, Malus x domestica, in orchards from Europe and Central Asia. Using clustering methods, we identified three distinct populations: (i) a large European population on domesticated and wild apples, (ii) a large Central Asian population on domesticated and wild apples in urban and agricultural areas, and (iii) a more geographically restricted population in M. sieversii forests growing in the eastern mountains of Kazakhstan. Unique allele richness and divergence time estimates supported a host-tracking co-evolutionary scenario in which this latter population represents a relict of the ancestral populations from which current populations found in human-managed habitats were derived. Our analyses indicated that the domestication of apple induced a significant change in the genetic differentiation of populations of V. inaequalis in its centre of origin, but had little impact on its population dynamics and mating system. We discuss how the structure of the apple-based agrosystem may have restricted changes in the population structure of the fungus in response to the domestication of its host.


Assuntos
Ascomicetos/genética , Evolução Molecular , Genética Populacional , Malus/microbiologia , Ásia Central , Cruzamento , Análise por Conglomerados , Ecossistema , Europa (Continente) , Haplótipos , Cazaquistão , Desequilíbrio de Ligação , Repetições de Microssatélites , Doenças das Plantas/microbiologia , Análise de Componente Principal
12.
Mycologia ; 102(3): 708-17, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20524602

RESUMO

Two new species of Stemphylium (anamorphic Pleospora) are described on the basis of morphological characters and molecular phylogenetic analyses. Stemphylium phaseolina and S. variabilis were isolated respectively from diseased leaves of Phaseolus vulgaris L. in Hebei Province, China, and from diseased leaves of Allium sativum L. in Angres, France. The two species exhibit characteristic Stemphylium morphology but are distinct from similar species based on the morphology and development of conidia. The internal transcribed spacer (ITS) nuclear rDNA region and glyceraldehyde-3-phosphate dehydrogenase (gpd) genes were sequenced. The results of maximum parsimony (MP) and maximum likelihood (ML) phylogenetic analyses of the combined DNA sequences of these two gene regions supported S. phaseolina and S. variabilis as two distinct phylogenetic species. The taxonomic descriptions of the new species and their comparison with related species are presented, together with the phylogenetic analysis based on combined DNA sequences of ITS and gpd gene regions.


Assuntos
Ascomicetos/classificação , DNA Espaçador Ribossômico/genética , Gliceraldeído-3-Fosfato Desidrogenases/genética , Filogenia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Ascomicetos/fisiologia , China , DNA Fúngico/análise , França , Alho/microbiologia , Técnicas de Tipagem Micológica , Phaseolus/microbiologia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Análise de Sequência de DNA , Especificidade da Espécie , Esporos Fúngicos/fisiologia
13.
Mycologia ; 102(2): 374-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20361504

RESUMO

A new species of Ulocladium was isolated from diseased leaves from two Cucumis sp. growing in Sinkiang and Gansu provinces of China. Conidia were isolated from necrotic leaves and used to establish single-spore pure cultures. Conidia were harvested from cultures 7 d after incubation for morphological comparisons. The morphology of this species resembles that of U. botrytis and U. consortiale. However it is distinguished from these two species by the sizes of obovoid to broadly ellipsoidal conidia and longer conidiophores. A taxonomic description of U. cantlous, comparison with related species in this genus, and a species phylogeny based on the partial nucleotide sequence of the glyceraldehyde-3-phosphate dehydrogenase (gpd) gene and the Alternaria alternata major allergen (Alt a 1) gene are provided.


Assuntos
Ascomicetos/isolamento & purificação , Cucumis melo , Doenças das Plantas/microbiologia , Ascomicetos/enzimologia , Ascomicetos/genética , Ascomicetos/ultraestrutura , Sequência de Bases , China , DNA Fúngico/química , DNA Fúngico/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/química , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência
14.
Genesis ; 47(8): 535-44, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19422018

RESUMO

Phytophthora capsici causes serious diseases in numerous crop plants. Polygalacturonases (PGs) are cell wall-degrading enzymes that play an important role in pathogenesis in straminopilous pathogens. To understand PGs as they relate to the virulence of P. capsici, Pcipg2 was identified from a genomic library of a highly virulent P. capsici strain. Pcipg2 was strongly expressed during symptom development after the inoculation of pepper leaves with P. capsici. The wild protein (PCIPGII) was obtained from the expression of pcipg2 and found that increasing activity of PGs in PCIPGII-treated pepper leaves was consistent with increasing symptom development. Asp residues in active sites within pcipg2 affected PCIPGII activity or its virulence on pepper leaves. Results show that pcipg2 is an important gene among pcipg genes, and illustrate the benefit of analyzing mechanisms of pathogenicity during the period of host/parasite interaction.


Assuntos
Capsicum/microbiologia , Proteínas Fúngicas/fisiologia , Phytophthora/fisiologia , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Western Blotting , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Dados de Sequência Molecular , Mutação , Phytophthora/genética , Phytophthora/patogenicidade , Folhas de Planta/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Virulência
15.
Mycologia ; 101(3): 417-22, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19537214

RESUMO

Piricaudiopsis punicae sp. nov., P. rosae sp. nov. and P. rhaphidophorae sp. nov., occurring respectively on dead branches of Punica granatum, Rosa chinensis and Rhaphidophora decursiva were collected from tropical forest in southern China. They differ from the three previously described Piricaudiopsis species in conidial morphology and proliferation of the conidiogenous cell. The presence or absence of percurrent proliferation of the conidiogenous cells and conidial appendages and the height of conidia are recognized as important characters in the delimitation of species of Piricaudiopsis. A key to Piricaudiopsis species is provided.


Assuntos
Fungos Mitospóricos/classificação , Araceae/microbiologia , China , Ecossistema , Lythraceae/microbiologia , Fungos Mitospóricos/citologia , Fungos Mitospóricos/isolamento & purificação , Fungos Mitospóricos/fisiologia , Rosa/microbiologia , Especificidade da Espécie , Esporos Fúngicos/citologia , Esporos Fúngicos/isolamento & purificação , Árvores/microbiologia
16.
Mycologia ; 101(4): 573-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19623939

RESUMO

Three species of the anamorphic fungus Shrungabeeja were collected from tropical forests in Yunnan Province, southern China. S. melicopeae sp. nov. and S. begoniae sp. nov. are described and illustrated from specimens collected respectively on dead branches of Melicope triphylla and Begonia semperflorens. S. vadirajensis is recorded for the first time from China. A key to the three known species of Shrungabeeja is provided.


Assuntos
Ascomicetos/classificação , Bambusa/microbiologia , Ascomicetos/citologia , China , Especificidade da Espécie , Esporos Fúngicos/citologia , Árvores/microbiologia
17.
Mycologia ; 100(3): 455-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18751552

RESUMO

Ulocladium subcucurbitae and U. brassicae are described and illustrated. These species were isolated from diseased leaves of Chenopodium glaucum and Brassica pekinensis from Guizhou and Yunnan provinces of China respectively.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Ascomicetos/citologia , Chenopodium/microbiologia , China , Microscopia , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Esporos Fúngicos/citologia
18.
Sci Rep ; 7(1): 7888, 2017 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-28801663

RESUMO

During our continuous survey (2012-2016) of saprobic hyphomycetes from dead branches in the forest ecosystems of southern China, we collected several acrodictys-like species. Acrodictys-like species are characterized by darkly pigmented and muriform conidia produced from holoblastic conidiogenous cells on macronematous, mononematous, cylindrical and unbranched or infrequently branched conidiophores. Phylogenetic analyses of ncLSU, ncSSU, ITS and tub2 sequence data lead us to propose two novel families in Sordariomycetes, Acrodictyaceae and Junewangiaceae. In addition, a new species, Acrodictys hainanensis, two new combinations, Junewangia queenslandica and Distoseptispora martinii, three new Chinese records, Acrodictys liputii, A. peruamazonensis and Junewangia sphaerospora are introduced. Two names, Acrodictys globulosa and A. malabarica, are resurrected.


Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Madeira/microbiologia , Ascomicetos/citologia , Ascomicetos/genética , China , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Microscopia , Filogenia , Pigmentos Biológicos/análise , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Esporos Fúngicos/citologia , Madeira/metabolismo
19.
Sci Rep ; 7(1): 7932, 2017 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-28801599

RESUMO

Ulocladium was thought to be a strictly asexual genus of filamentous fungi. However, Ulocladium strains were shown to possess both MAT1-1-1 and MAT1-2-1 genes as observed in homothallic filamentous Ascomycetes. Here, we demonstrate that the U. botrytis MAT genes play essential roles for controlling asexual traits (conidial size and number). Using reciprocal genetic transformation, we demonstrate that MAT genes from the related heterothallic species Cochliobolus heterostrophus can also influence U. botrytis colony growth, conidial number and size, and have a strong effect on the range of the number of septa/conidium. Moreover, U. botrytis MAT genes can also affect similar aspects of asexual reproduction when expressed in C. heterostrophus. Heterologous complementation using C. heterostrophus MAT genes shows that they have lost the ability to regulate sexual reproduction in U. botrytis, under the conditions we employed, while the reciprocal heterologous complementation demonstrates that U. botrytis MAT genes have the ability to partially induce sexual reproduction in C. heterostrophus. Thus, the genetic backgrounds of C. heterostrophus and U. botrytis play significant roles in determining the function of MAT genes on sexual reproduction in these two fungi species. These data further support the role of MAT genes in controlling asexual growth in filamentous Ascomycetes but also confirm that heterothallic and homothallic Dothideomycete fungi can be interconverted by the exchange of MAT genes.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Ascomicetos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Genes Fúngicos Tipo Acasalamento , Teste de Complementação Genética , Transformação Genética
20.
Angew Chem Int Ed Engl ; 37(19): 2675-2678, 1998 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-29711598

RESUMO

The stabilization of the transition state through a favorable interaction between the double bond of 1 and the carbonyl group of 2 appears to be responsible for the high diastereoface selectivity of the aldol reaction. This key step in the highly concise total synthesis of epothilone B is followed by a Suzuki coupling to introduce the thiazole domain, a Noyori reduction to control the stereochemistry at C3, and a final macrolactonization (see reaction scheme). X=protecting group.

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