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1.
Sci Rep ; 14(1): 9298, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654032

RESUMO

Agaricales, Russulales and Boletales are dominant orders among the wild mushrooms in Basidiomycota. Boletaceae, one of the major functional elements in terrestrial ecosystem and mostly represented by ectomycorrhizal symbionts of trees in Indian Himalaya and adjoining hills, are extraordinarily diverse and represented by numerous genera and species which are unexplored or poorly known. Therefore, their hidden diversity is yet to be revealed. Extensive macrofungal exploration by the authors to different parts of Himalaya and surroundings, followed by through morphological studies and multigene molecular phylogeny lead to the discovery of five new species of wild mushrooms: Leccinellum bothii sp. nov., Phylloporus himalayanus sp. nov., Phylloporus smithii sp. nov., Porphyrellus uttarakhandae sp. nov., and Retiboletus pseudoater sp. nov. Present communication deals with morphological details coupled with illustrations and phylogenetic inferences. Besides, Leccinellum sinoaurantiacum and Xerocomus rugosellus are also reported for the first time from this country.


Assuntos
Agaricales , Filogenia , Índia , Agaricales/genética , Agaricales/classificação , DNA Fúngico/genética , Basidiomycota/genética , Basidiomycota/classificação
2.
J Fungi (Basel) ; 9(7)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37504742

RESUMO

Repeated macrofungal explorations, followed by thorough examination of species through morphology and molecular phylogeny, have made it clear that European and American names of wild mushrooms were inadvertently misapplied quite often to Asian lookalikes by mycologists/taxonomists in the past. Therefore, in order to reveal this mushroom treasure, in recent years, taxonomical research on wild mushrooms has been intensified in Asian countries, including India, by undertaking a combined approach of morpho-taxonomy and multigene molecular phylogeny. Boletoid mushrooms (Boletaceae) are no exception. While working on boletoid mushrooms of the Indian Himalayas, authors recently came across six interesting species of boletoid mushrooms. In the present communication, four novel species, namely Leccinellum binderi, Cyanoboletus paurianus, Xerocomus uttarakhandae, and Xerocomellus himalayanus, are established based on morphology and molecular phylogenetic estimations. Moreover, Cyanoboletus macroporus and Xerocomus fraternus are also reported here for the first time in India.

3.
MycoKeys ; 75: 1-29, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33223919

RESUMO

Russula subsection Amoeninae is morphologically defined by a dry velvety pileus surface, a complete absence of cystidia with heteromorphous contents in all tissues, and spores without amyloid suprahilar spot. Thirty-four species within subsection Amoeninae have been published worldwide. Although most Russula species in South Korea have been assigned European or North American names, recent molecular studies have shown that Russula species from different continents are not conspecific. Therefore, the present study aims to: 1) define which species of Russula subsection Amoeninae occur on each continent using molecular phylogenetic analyses; 2) revise the taxonomy of Korean Amoeninae. The phylogenetic analyses using the internal transcribed spacer (ITS) and multilocus sequences showed that subsection Amoeninae is monophyletic within subgenus Heterophyllidiae section Heterophyllae. A total of 21 Russula subsection Amoeninae species were confirmed from Asia, Australia, Europe, North America, and Central America, and species from different continents formed separate clades. Three species were recognized from South Korea and were clearly separated from the European and North American species. These species are R. bella, also reported from Japan, a new species described herein, Russula orientipurpurea, and a new species undescribed due to insufficient material.

4.
MycoKeys ; (37): 73-92, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30150881

RESUMO

Amanitatullossiana, a new species of Amanita [subgenus Lepidella] section Lepidella from India is described. The species is characterised by its ash grey to brownish-grey pileus covered with dark grey to greyish-black universal veil remnants, the upper part of its rooting stipe base covered by several rows of recurved scales, broadly ellipsoid to ellipsoid basidiospores, absence of basidial clamp connections and pileal remnants of universal veil comprising abundant, disordered inflated cells intermixed with scattered filamentous hyphae. Molecular phylogenetic analysis and morphology both support the association of A.tullossiana with species of Bas' stirps Cinereoconia - A.cinereoconia and A.griseoverrucosa. Two species, A.griseoverrucosa and A.virgineoides are reported here as new records for India.

5.
MycoKeys ; (33): 103-124, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29686503

RESUMO

Tylopilus himalayanus and T. pseudoballoui are described as new species from two Himalayan states (Sikkim and Uttarakhand) in India. Tylopilus himalayanus is characterised by a unique combination of features: reddish- or brownish-grey to purplish-grey then brown to reddish-brown or darker pileus, absence of olive or violet tinges on stipe surface, angular pores, stipe without reticulum or rarely with a faint reticulum restricted to the very apex, bitter taste of the context and positive macrochemical colour reaction of the stipe context with KOH (dark orange) and FeSO4 (dark green), medium sized (10.9-14.4 × 3.9-4.9 µm) basidiospores and occurrence under coniferous trees; T. pseudoballoui is distinguished by orange-yellow to brown-yellow sticky pileus, pale yellow pore surface with pinkish hues that turns pale to greyish-orange on bruising; angular pores, stipe concolorous to pileus with pruinose but never reticulate surface, ixocutis pattern of pileipellis and occurrence under broadleaf trees. Another species, T. neofelleus, which was reported earlier from China and Japan, was also collected from Sikkim and reported for the first time from India. All three species are described with morphological details and two-locus based (nrLSU and nrITS) phylogenetic data.

6.
MycoKeys ; (44): 123-135, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30613182

RESUMO

An interesting species of the genus Gliophorus (sect.Glutinosae), collected from Sikkim Himalaya in India, is described here as G.glutinosus sp. nov. after thorough morphological examination and phylogenetic analysis. The species is mainly characterised by its strongly glutinous basidiomata throughout, particularly on the twisted stipe, decurrent lamellae with glutinous edge, gelatinised cheilocystidia, presence of pleuropseudocystidia and absence of clamps in hyphae of the pileipellis. This communication includes detailed morphological description, illustrations, comparison with the allied taxa, nrITS based phylogeny of this novel taxon and a key to the species under Gliophorussect.Glutinosae.

7.
PLoS One ; 12(5): e0178050, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28552988

RESUMO

Mushrooms have been prized by humankind as medicine and culinary wonder since antiquity. Though several species are ethnically valued; many prospective species are still being discovered. One such wild macrofungus has recently been discovered during subsequent field surveys in West Bengal, India which in turn exposed as a traditionally consumed popular myco-food. The collected taxon was found to be unique with regard to its morphological as well as genetical features. After detailed characterizations, the fungus was identified as a novel taxon belonging to the genus Russula (Russulaceae, Basidiomycota). Besides, the investigation was further extended in search of new functional ingredients and in this context, a water soluble crude polysaccharide rich extract (Rusalan) was isolated from dried basidiocarps. Accumulating evidences from GC-MS, HPTLC, FT-IR along with several spectrophotometric methods postulated that the fraction consisted mainly of carbohydrate in triple helical conformation, where glucose was the major monosaccharide mostly with ß-type glycosidic linkage. Conversely, Rusalan showed pronounced antioxidant activity in six in vitro assay systems with EC50 value ranging from 190-1328 µg/ml concentration. The crude polysaccharide was also evaluated against six bacterial strains using microdilution method and the growth of Staphylococcus aureus and Bacillus subtilis were found to be inhibited effectively. In addition, immune-stimulatory assays demonstrated that Rusalan could evidently promote proliferation, induce phagocytosis, release NO, produce intracellular ROS and upregulate mRNA expression of iNOS, TNF-α, COX-2, as well as IL-6 genes in in mouse macrophage cells. Therefore, aim of the present study was not only to describe a new taxon to the world mycoflora but also to introduce a potent therapeutic agent that could be explored for food and pharmaceutical purposes. However, isolation of active component and in vivo studies need to be designed further.


Assuntos
Agaricales , Terapias Complementares , Adjuvantes Imunológicos/farmacologia , Agaricales/classificação , Agaricales/genética , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Linhagem Celular , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Camundongos , Filogenia , Reação em Cadeia da Polimerase , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Fungal Biol ; 120(12): 1554-1581, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27890091

RESUMO

Lactarius subg. Russularia is a large group of milkcaps occurring almost worldwide and dominant in many ecosystems. In this study we focus on new diversity, evolutionary relationships, divergence time, and origin of the subgenus. Six conifer symbionts are described as new to science: Lactarius atrii, L. aurantionitidus, L. dombangensis, L. flavigalactus, L. lachungensis, and L. sikkimensis. Species delimitation is assessed based on the concordance between morphological characteristics and an ITS phylogeny. Infrageneric relationships were studied using a phylogeny constructed from concatenated ITS-rpb2 data using Maximum Likelihood and Bayesian inference. Results show that species in this subgenus do not cluster together according to their geographic origin. Intercontinental sister relationships between Europe/Asia/North America are common but actual conspecificity is rare. This result suggests that allopatric speciation has played an important role within this subgenus. Only few morphological characteristics tend to be phylogenetically informative, with the most important being presence or absence of true cystidia and the pileipellis structure. Two datasets were generated in order to estimate the age of L. subg. Russularia. The results suggest the origin of L. subg. Russularia to be in the Mid Miocene period.


Assuntos
Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Variação Genética , Filogenia , Ásia , Basidiomycota/genética , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Evolução Molecular , RNA Polimerase II/genética , Análise de Sequência de DNA , Traqueófitas/microbiologia
9.
Mycologia ; 108(4): 753-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27153883

RESUMO

Xerocomus doodhcha and Hortiboletus indorubellus (Boletaceae) from broadleaf montane forest in Sikkim, India, are proposed as new. They are described in detail with supporting morphological illustrations and compared with related taxa using molecular phylogenetic analysis of ITS and 28S rDNA sequences. Xerocomus doodhcha is characterized by a pale brown pileus, basidiospores with a finely bacillate surface under SEM, and phylogenetic proximity to the type species of Xerocomus, X. subtomentosus Hortiboletus indorubellus is characterized by a dark brown to reddish brown pileus, context that turns brownish to brownish orange on bruising, and phylogenetic proximity to Hortiboletus rubellus.


Assuntos
Basidiomycota/classificação , Basidiomycota/isolamento & purificação , Basidiomycota/citologia , Basidiomycota/genética , Betula/microbiologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Fagaceae/microbiologia , Florestas , Microscopia , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Siquim
10.
IMA Fungus ; 4(2): 359-69, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24563842

RESUMO

Two taxa, Hericium yumthangense (Russulales, Agaricomycotina) and Mycoleptodonoides sharmae (Polyporales, Agaricomycotina) are described as new to science from the Shingba Rhododendron sanctuary located in the northern district of Sikkim, India. Macro- and micromorphological characters are described and illustrated for both species, which are compared with allied taxa. ITS rDNA sequences supported H. yumthangense as a rather isolated species within Hericium, the species complexes of which were not resolved due to low interspecific sequence divergence. In the case of M. sharmae, 28S rDNA (D1/D2) data rendered this poorly known genus among well-known taxa of the core-polyporoid clade.

11.
Nat Rev Drug Discov ; 11(12): 937-57, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23197040

RESUMO

Protein kinase C (PKC) has been a tantalizing target for drug discovery ever since it was first identified as the receptor for the tumour promoter phorbol ester in 1982. Although initial therapeutic efforts focused on cancer, additional indications--including diabetic complications, heart failure, myocardial infarction, pain and bipolar disorder--were targeted as researchers developed a better understanding of the roles of eight conventional and novel PKC isozymes in health and disease. Unfortunately, both academic and pharmaceutical efforts have yet to result in the approval of a single new drug that specifically targets PKC. Why does PKC remain an elusive drug target? This Review provides a short account of some of the efforts, challenges and opportunities in developing PKC modulators to address unmet clinical needs.


Assuntos
Proteína Quinase C/antagonistas & inibidores , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/etiologia , Ensaios Clínicos como Assunto , Complicações do Diabetes/tratamento farmacológico , Ativação Enzimática , Cardiopatias/tratamento farmacológico , Cardiopatias/etiologia , Humanos , Isoenzimas/fisiologia , Neoplasias/tratamento farmacológico , Neoplasias/etiologia , Transplante de Órgãos , Proteína Quinase C/química , Proteína Quinase C/fisiologia
12.
Expert Opin Drug Discov ; 3(7): 761-74, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23496219

RESUMO

BACKGROUND: ATP-competitive inhibitors of protein kinases have been successfully developed for life-threatening indications such as cancer. However, owing to the similarity of the ATP binding sites between kinases, it has been challenging to identify specific inhibitors. The progress towards the generation of kinase inhibiting drugs for more chronic indications has been slowed by the concern that low specificity kinase inhibitors will have undesired toxicities. OBJECTIVE AND METHODS: We have reviewed the scientific and patent literature to summarize alternative strategies that are being used to develop non-ATP-competitive kinase inhibitors with greater selectivity. RESULTS/CONCLUSION: Several new approaches are being taken to achieve selectivity. Among these, the use of small peptide therapeutics is particularly promising and is already yielding drugs that are demonstrating promise in human clinical trials.

13.
Biochem J ; 385(Pt 1): 11-20, 2005 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-15485396

RESUMO

ML-IAP (melanoma inhibitor of apoptosis) is a potent anti-apoptotic protein that is strongly up-regulated in melanoma and confers protection against a variety of pro-apoptotic stimuli. The mechanism by which ML-IAP regulates apoptosis is unclear, although weak inhibition of caspases 3 and 9 has been reported. Here, the binding to and inhibition of caspase 9 by the single BIR (baculovirus IAP repeat) domain of ML-IAP has been investigated and found to be significantly less potent than the ubiquitously expressed XIAP (X-linked IAP). Engineering of the ML-IAP-BIR domain, based on comparisons with the third BIR domain of XIAP, resulted in a chimeric BIR domain that binds to and inhibits caspase 9 significantly better than either ML-IAP-BIR or XIAP-BIR3. Mutational analysis of the ML-IAP-BIR domain demonstrated that similar enhancements in caspase 9 affinity can be achieved with only three amino acid substitutions. However, none of these modifications affected binding of the ML-IAP-BIR domain to the IAP antagonist Smac (second mitochondrial activator of caspases). ML-IAP-BIR was found to bind mature Smac with low nanomolar affinity, similar to that of XIAP-BIR2-BIR3. Correspondingly, increased expression of ML-IAP results in formation of a ML-IAP-Smac complex and disruption of the endogenous interaction between XIAP and mature Smac. These results suggest that ML-IAP might regulate apoptosis by sequestering Smac and preventing it from antagonizing XIAP-mediated inhibition of caspases, rather than by direct inhibition of caspases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Proteínas de Transporte/metabolismo , Inibidores de Caspase , Inibidores de Cisteína Proteinase/química , Inibidores de Cisteína Proteinase/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas de Neoplasias/metabolismo , Engenharia de Proteínas , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Sequência de Aminoácidos , Proteínas Reguladoras de Apoptose , Sítios de Ligação , Proteínas de Transporte/química , Proteínas de Transporte/genética , Caspase 9 , Caspases/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Cristalografia por Raios X , Inibidores de Cisteína Proteinase/genética , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Proteínas Inibidoras de Apoptose , Peptídeos e Proteínas de Sinalização Intracelular , Cinética , Proteínas Mitocondriais/química , Proteínas Mitocondriais/genética , Modelos Moleculares , Dados de Sequência Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas/química , Proteínas/genética , Proteínas/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X
14.
J Am Chem Soc ; 124(31): 9036-7, 2002 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-12148992

RESUMO

Molecules capable of complementary hydrogen bonding were used to control the noncovalent self-assembly and electronic properties of a chemically well-defined surface mesostructure. In this work, we patterned a footprint region for molecular assembly on a surface and used moieties featuring complementary recognition to tune the current-voltage properties of the patterned region. With the appropriate functionalities on the complementary moieties, we were able to increase and decrease the observed conductance in surface-bound mesoscale structures imaged by scanning tunneling microscopy (STM).

15.
J Am Chem Soc ; 124(28): 8290-6, 2002 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-12105909

RESUMO

A model system for the characterization of molecular recognition events in molecularly imprinted polymers (MIPs) is presented. The use of a biologically inspired, three-point hydrogen-bonding motif and a thin film polymeric matrix allows for pre- and post-polymerization binding properties to be characterized by infrared spectroscopy. A method to determine binding constants was developed and utilized before and after cross-linking. These values showed a 10-fold decrease in binding after polymerization, which was attributed to an increase in molecular confinement after polymerization and a change in the local structural environment of the binding cavity. Transport of the guest molecule was shown to be reversible.


Assuntos
Acrilatos/química , Polímeros/química , Propilenoglicóis/química , Piridinas/química , Timina/análogos & derivados , Cinética , Mimetismo Molecular , Polímeros/metabolismo , Espectrofotometria Infravermelho , Moldes Genéticos , Termodinâmica
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