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1.
J Chem Ecol ; 45(8): 715-724, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31385154

RESUMO

Plants emit a specific blend of volatiles in response to herbivory and these volatiles, which often attract predators and parasitoids function as an indirect plant defense. The impact of plant volatiles in shaping herbivore defenses is unclear. Here, we report that specific plant volatiles induce immune responses in the polyphagous herbivore, Spodoptera litura. We characterized the hemocyte profile and established their functional significance with respect to ontogeny and exposure to specific plant volatiles. Fifth instar larvae showed the highest number and hemocytes diversity. We characterized seven different types of hemocytes, of which granulocytes performed phagocytosis, oenocytoids showed melanization activity, and plasmatocytes along with granulocytes and oenocytoids were found to be involved in encapsulation. Among the six volatiles tested, exposure to (E)-ß-ocimene caused the highest increase in total hemocytes number (THC) followed by linalool and (Z)-3-hexenyl acetate exposure. Although THC did not differ between these three volatile treatments, circulating hemocytes diversity varied significantly. (E)-ß-ocimene exposure showed higher number of plasmatocytes and phenol oxidase activity. The interaction of the parasitic wasp Bracon brevicornis with (E)-ß-ocimene exposed larvae was poor in terms of delayed paralysis and lower egg deposition. In choice assays, the wasp showed clear preference towards control larvae indicating (E)-ß-ocimene treatment renders the host unattractive. Hemocyte profiles post-parasitoid exposure and (E)-ß-ocimene treatment were similar indicating cue-based priming. When challenged with Bacillus thuringiensis, linalool exposure resulted in the highest survival as compared to other volatiles. Our results show that specific HIPVs can modulate cellular immunity of S. litura, revealing a new role for HIPVs in tri-trophic interactions.


Assuntos
Compostos Orgânicos Voláteis/farmacologia , Vespas/fisiologia , Alcenos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Hemócitos/citologia , Hemócitos/efeitos dos fármacos , Hemócitos/metabolismo , Herbivoria , Interações Hospedeiro-Parasita , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/metabolismo , Larva/fisiologia , Monofenol Mono-Oxigenase/metabolismo , Monoterpenos/farmacologia , Oviposição/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Plantas/química , Plantas/metabolismo , Plantas/parasitologia , Compostos Orgânicos Voláteis/química , Vespas/imunologia
2.
Chem Pharm Bull (Tokyo) ; 67(7): 654-665, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257321

RESUMO

Quassinoids, one kind of triterpenoids with multiple bioactivities such as anti-cancer, anti-malarial, anti-oxidative, anti-microbial, anti-diabetic, anti-viral, and anti-inflammatory effects, have drawn much attention in recent years. Between 2004 and 2018, the structural characteristics and plant sources of 190 quassinoids were reported. Herein, the structure-activity relationships (SARs) of quassinoids along with the anti-cancer mechanisms of four representative quassinoids, eurycomanone, bruceine D, dehydrobruceine B, and brusatol are discussed. This review might be useful for further research and development of quassinoids.


Assuntos
Antineoplásicos Fitogênicos/química , Quassinas/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , Antivirais/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Plantas/química , Plantas/metabolismo , Plasmodium falciparum/efeitos dos fármacos , Quassinas/isolamento & purificação , Quassinas/farmacologia , Relação Estrutura-Atividade , Vírus do Mosaico do Tabaco/efeitos dos fármacos
3.
BMC Bioinformatics ; 20(Suppl 13): 382, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31337335

RESUMO

BACKGROUND: Pathogenic protist membrane transporter proteins play important roles not only in exchanging molecules into and out of cells but also in acquiring nutrients and biosynthetic compounds from their hosts. Currently, there is no centralized protist membrane transporter database published, which makes system-wide comparisons and studies of host-pathogen membranomes difficult to achieve. RESULTS: We analyzed over one million protein sequences from 139 protists with full or partial genome sequences. Putative transmembrane proteins were annotated by primary sequence alignments, conserved secondary structural elements, and functional domains. We have constructed the PPTdb (Pathogenic Protist Transmembranome database), a comprehensive membrane transporter protein portal for pathogenic protists and their human hosts. The PPTdb is a web-based database with a user-friendly searching and data querying interface, including hierarchical transporter classification (TC) numbers, protein sequences, functional annotations, conserved functional domains, batch sequence retrieving and downloads. The PPTdb also serves as an analytical platform to provide useful comparison/mining tools, including transmembrane ability evaluation, annotation of unknown proteins, informative visualization charts, and iterative functional mining of host-pathogen transporter proteins. CONCLUSIONS: The PPTdb collected putative protist transporter proteins and offers a user-friendly data retrieving interface. Moreover, a pairwise functional comparison ability can provide useful information for identifying functional uniqueness of each protist. Finally, the host and non-host protein similarity search can fulfill the needs of comprehensive studies of protists and their hosts. The PPTdb is freely accessible at http://pptdb.cgu.edu.tw .


Assuntos
Bases de Dados Factuais , Proteínas de Membrana Transportadoras/análise , Interface Usuário-Computador , Fungos/metabolismo , Humanos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Plantas/metabolismo
4.
J Agric Food Chem ; 67(32): 8740-8745, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31334643

RESUMO

Just recently, the "horizontal natural product transfer" was unveiled: alkaloids, which have been leached out from decomposing alkaloidal donor plants, are taken up by the roots of acceptor plants. In the same manner, many other natural products, such as coumarins or stilbenes, are also taken up from the soil. Recent research outlined that alkaloids are transferred also from a living donor plant to plants growing in their vicinity. In the acceptor plants, the imported natural products might be modified by hydroxylation and glucosylation. These insights will strongly impact our understanding of contamination of plant-derived commodities as well as plant-plant interactions.


Assuntos
Produtos Biológicos/metabolismo , Plantas/metabolismo , Alcaloides/análise , Alcaloides/metabolismo , Produtos Biológicos/análise , Transporte Biológico , Raízes de Plantas/metabolismo , Plantas/química
5.
Environ Monit Assess ; 191(7): 475, 2019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31256284

RESUMO

Given the spatial and temporal variability in hydrological conditions and nitrogen (N) processes, it is of great uncertainty to identify the N sources and evaluate N transformation processes in the upper Han River. Investigations were conducted in November 2015 and January, April, and July 2016, using an isotopic method and water quality monitoring. The significant and positive correlation between NO3- concentrations and Cl- (p < 0.01) in most sampling months suggested that the great influence of human activities and sewage or manure was the dominant NO3- source. The δ15NO3- values and NO3-/Cl- variations indicated that riverine N mainly came from soil organic N and sewage in November. Fertilizer and sewage were the major N sources in January and April, respectively. In July, water was influenced by various N inputs. The nitrification process played an important role in the low δ15NO3- values in January, while both nitrification and plant uptake resulted in the increase in δ15NH4+ values in April. The simultaneous effect of N fixation and plant uptake maintained the stabilization of δ15NH4+ concentrations. Our study provides theoretical basis on N sources and transformations for controlling N pollution and improving water quality in the upper Han River in the near future.


Assuntos
Nitrogênio/análise , Rios/química , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental/métodos , Nitrificação , Nitrogênio/metabolismo , Isótopos de Nitrogênio/análise , Isótopos de Nitrogênio/metabolismo , Plantas/metabolismo , Estações do Ano , Solo/química
6.
Biol Res ; 52(1): 39, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358053

RESUMO

In the growth condition(s) of plants, numerous secondary metabolites (SMs) are produced by them to serve variety of cellular functions essential for physiological processes, and recent increasing evidences have implicated stress and defense response signaling in their production. The type and concentration(s) of secondary molecule(s) produced by a plant are determined by the species, genotype, physiology, developmental stage and environmental factors during growth. This suggests the physiological adaptive responses employed by various plant taxonomic groups in coping with the stress and defensive stimuli. The past recent decades had witnessed renewed interest to study abiotic factors that influence secondary metabolism during in vitro and in vivo growth of plants. Application of molecular biology tools and techniques are facilitating understanding the signaling processes and pathways involved in the SMs production at subcellular, cellular, organ and whole plant systems during in vivo and in vitro growth, with application in metabolic engineering of biosynthetic pathways intermediates.


Assuntos
Reguladores de Crescimento de Planta/metabolismo , Fenômenos Fisiológicos Vegetais , Metabolismo Secundário/fisiologia , Estresse Fisiológico/fisiologia , Técnicas de Cultura de Células , Regulação da Expressão Gênica de Plantas/fisiologia , Raízes de Plantas/metabolismo , Brotos de Planta/metabolismo , Plantas/metabolismo , Transdução de Sinais
7.
Environ Sci Pollut Res Int ; 26(23): 23696-23706, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203550

RESUMO

Excessive nitrogen accumulated from wastewater with low C/N ratio is a new threat to water ecosystem. In this study, surface flow constructed wetland (SFCW) and floating treatment wetland (FTW) planted with Iris pseudacorus were set in parallel for nitrogen removal. The nitrogen removal efficiencies and pathways, as well as the abundance and functional diversities of the microbial community, were investigated. The results demonstrated that SFCW generally had better nitrogen removal performance than FTW did over four seasons. The average total nitrogen removal efficiency was 66.0% and 43.8% in SFCW and FTW, respectively. The plant uptake played a vital role in nitrogen reduction, which accounted for 29.3% and 7.7% of the total removed nitrogen in SFCW and FTW, respectively. A combination of high-throughput sequencing and quantitative polymerase chain reaction analysis revealed that the two wetland systems had complete nitrogen cycling, and the narG gene was the dominant nitrogen-transformation functional gene in both systems. More abundant denitrifying genes in SFCW than in FTW were also responsible for higher removal capacity of nitrogen. The results suggest that the planting pattern of wetland vegetation has an important impact on nitrogen removal efficiency by influencing the plant absorption and the development of microbial communities.


Assuntos
Iris (Planta)/metabolismo , Nitrogênio/metabolismo , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Desnitrificação , Ecossistema , Nitrogênio/análise , Ciclo do Nitrogênio , Plantas/metabolismo , Estações do Ano , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análise
8.
Biochemistry (Mosc) ; 84(5): 491-508, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31234764

RESUMO

The photosynthetic apparatus accomplishes two major functions in plants - solar energy conversion and protection of the plant from photodestruction. Its highly orchestrated formation includes coordinated biosynthesis of chlorophyll (Chl) and of its binding to matrix proteins. Light plays here the central role driving both metabolic and regulatory processes. The regulation is achieved via operation of sophisticated photoreceptor machinery with the phytochrome system as its main component. This review concentrates on Chl a biosynthesis and the role of phytochrome A (phyA) in this process. The mechanism of action of phyA and the specificity of its state in the plant has been described, in particular, the existence of two native types with different modes of action. This review touches upon the dependence of the effects of phyA on tissues and organs of the plant and its species, genetic modifications, and hormonal status.


Assuntos
Clorofila/biossíntese , Fitocromo A/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Luz , Complexos de Proteínas Captadores de Luz/metabolismo , Fotossíntese , Plantas/metabolismo , Protoclorifilida/metabolismo
9.
J Agric Food Chem ; 67(27): 7561-7568, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31246021

RESUMO

The development of botanical applications of nanomaterials has produced a new generation of technologies that can profoundly impact botanical research. Semiconductor quantum dots (QDs) are an archetype nanomaterial and have received significant interest from diverse research communities, owing to their unique and optimizable optical properties. In this review, we describe the most recent progress on QD-based botanical research and discuss the uptake, translocation, and effects of QDs on plants and the potential applications of QDs in botany. A critical evaluation of the current limitations of QD technologies is discussed, along with the future prospects in QD-based botanical research.


Assuntos
Botânica/tendências , Pontos Quânticos , Semicondutores/tendências , Parede Celular/metabolismo , Hidroponia , Células Vegetais/metabolismo , Células Vegetais/ultraestrutura , Desenvolvimento Vegetal , Fenômenos Fisiológicos Vegetais , Plantas/genética , Plantas/metabolismo , Solo
10.
J Agric Food Chem ; 67(25): 7183-7189, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31150243

RESUMO

As a result of the important roles of boron (B) in the growth of plants, the uptake of B by plants is dependent upon the existing form and content of available B in soil, which can bring about the local cycle of B isotope equilibrium. A method using water-heating extraction combined with three-step ion-exchange chromatography was developed for the extraction and isotopic analysis of available B in soil. The extraction efficiency and fractionation of B isotopic composition in the procedure were investigated. The results showed that, in the upper layers of soils, the change of δ11B values was opposite that of the mass concentration and a similar variation between δ11B and content occurred in the lower layers. The isotope of available B in soil can create a featured isotopic signature to further understand the geochemical details related to the soil properties and molecular mechanism of B uptake in plants.


Assuntos
Boro/análise , Isótopos/análise , Solo/química , Boro/metabolismo , Isótopos/metabolismo , Espectrometria de Massas , Plantas/metabolismo
11.
Sci Total Environ ; 684: 670-681, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31158628

RESUMO

Peat carbon accumulation is controlled by both large scale factors, such as climate and hydrological setting, and small scale factors, such as microtopography and plant community. These small scale factors commonly vary within peatlands and can cause variation in biogeochemical traits and carbon accumulation within the same site. To understand these within-site variations, we investigated long term carbon accumulation, peat decomposition, biogeochemistry of pore water and plant macrofossils along a transect in an ombrotrophic bog in southern Patagonia. An additional question we addressed is how historical deposition of volcanic ash on the peatland has affected its carbon balance. Variability in plant community and water table led to differences in long term peat and carbon accumulation (peat moss > cushion plant), organic matter decomposition (cushion plant > peat moss), and methane production (peat moss > cushion plant). Macrofossil analysis and radiocarbon dating indicated a relationship between plant community and carbon accumulation or decomposition during the historical succession of vegetation in the peatland. C/N ratio and isotopic signatures reflected variability in plant community as litter source, and DOC concentrations were controlled by humification level. Volcanic ash deposition had only limited effect on plant composition, but it was associated with increased decomposition in overlying peat layers. This study highlights the importance of understanding how plant communities develop, as changes in communities could significantly affect the potential of ombrotrophic peatlands as C sink.


Assuntos
Biota/fisiologia , Carbono/metabolismo , Plantas/metabolismo , Áreas Alagadas , Argentina
12.
Ecotoxicol Environ Saf ; 181: 419-427, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31220782

RESUMO

Nonylphenol (NP) and its detrimental effects on the environment, humans, wildlife, fish and birds is an increasingly important global research focus. The number of investigations on the toxicity and metabolic fate of NP in plants is however limited. This paper reviews the prevalence and source of NP in plants and the effect it has on its morphological, physiological and ultrastructural status. Fruit and vegetables have been found to contain levels of NP that is twenty-fold exceeding the no observable effect level (NOEL) of freshwater algae. Apart from the potential risk this poses to the health of consumers, it can overburden the plant's natural defence system, leading to growth disorders. Plants exposed to NP show signs of overall growth reduction, changes in organelle structure and oxidative damage. These adverse effects may exacerbate the food security dilemma faced by many countries and impede their progress towards attaining the sustainable development goals.


Assuntos
Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Fenóis/toxicidade , Plantas/efeitos dos fármacos , Animais , Disruptores Endócrinos/análise , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Frutas/química , Frutas/crescimento & desenvolvimento , Humanos , Fenóis/análise , Desenvolvimento Vegetal/efeitos dos fármacos , Plantas/anatomia & histologia , Plantas/metabolismo , Verduras/química , Verduras/crescimento & desenvolvimento
13.
Plant Physiol Biochem ; 139: 691-696, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31054471

RESUMO

Industrialization and inevitable mining has resulted in the release of some metals in environments, which have numerous industrial roles on one hand and also showed environmental toxicity on other hand. Beryllium is one of them, it has been used in number of industries however its excess use or inappropriate disposal of beryllium resulted in high beryllium accumulation in soil and ground water. This subsequently is affecting our environment and more potentially arable crop production. Beryllium has been extensively studied in humans and reported as toxic metal. In plants, only few studies have been documented toxic effects of beryllium in plants. Moreover, plant products (fruits, grains or other plant parts) could be major source of beryllium toxicity in our food chain therefore it is more imperative to understand how plant can be developed more tolerant to beryllium toxicity. In this short mini-review article, we primarily highlighted and speculated different beryllium uptake, translocation and beryllium storage mechanism in plants. This article provides considerable information for people who are working in identifying and developing heavy metal hyper accumulators plants.


Assuntos
Berílio/metabolismo , Berílio/toxicidade , Plantas/metabolismo , Biodegradação Ambiental , Poluição Ambiental/prevenção & controle , Plantas/efeitos dos fármacos
14.
Plant Sci ; 284: 203-211, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084873

RESUMO

The transport and targeting of mRNAs to specific intracellular locations is a ubiquitous process in prokaryotic and eukaryotic organisms. Despite the prevalent nature of RNA localization in guiding development, differentiation, cellular movement and intracellular organization of biochemical activities, only a few examples exist in higher plants. Here, we summarize past studies on mRNA-based protein targeting to specific subdomains of the cortical endoplasmic reticulum (ER) using the rice storage protein mRNAs as a model. Such studies have demonstrated that there are multiple pathways of RNA localization to the cortical ER that are controlled by cis-determinants (zipcodes) on the mRNA. These zipcode sequences are recognized by specific RNA binding proteins organized into multi-protein complexes. The available evidence suggests mRNAs are transported to their destination sites by co-opting membrane trafficking factors. Lastly, we discuss the major gaps in our knowledge on RNA localization and how information on the targeting of storage protein mRNAs can be used to further our understanding on how plant mRNAs are organized into regulons to facilitate protein localization and formation of multi-protein complexes.


Assuntos
Oryza/metabolismo , Plantas/metabolismo , RNA de Plantas/metabolismo , Proteínas de Armazenamento de Sementes/metabolismo , Modelos Biológicos , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo
15.
Plant Sci ; 284: 37-47, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31084877

RESUMO

Machine learning (ML) is a field of artificial intelligence that has rapidly emerged in molecular biology, thus allowing the exploitation of Big Data concepts in plant genomics. In this context, the main challenges are given in terms of how to analyze massive datasets and extract new knowledge in all levels of cellular systems research. In summary, ML techniques allow complex interactions to be inferred in several biological systems. Despite its potential, ML has been underused due to complex computational algorithms and definition terms. Therefore, a systematic review to disentangle ML approaches is relevant for plant scientists and has been considered in this study. We presented the main steps for ML development (from data selection to evaluation of classification/prediction models) with a respective discussion approaching functional genomics mainly in terms of pathogen effector genes in plant immunity. Additionally, we also considered how to access public source databases under an ML framework towards advancing plant molecular biology and introduced novel powerful tools, such as deep learning.


Assuntos
Aprendizado de Máquina , Biologia Molecular/métodos , Plantas/genética , Bases de Dados Genéticas , Plantas/metabolismo
16.
Nat Commun ; 10(1): 2203, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101818

RESUMO

The root economics spectrum (RES), a common hypothesis postulating a tradeoff between resource acquisition and conservation traits, is being challenged by conflicting relationships between root diameter, tissue density (RTD) and root nitrogen concentration (RN). Here, we analyze a global trait dataset of absorptive roots for over 800 plant species. For woody species (but not for non-woody species), we find nonlinear relationships between root diameter and RTD and RN, which stem from the allometric relationship between stele and cortical tissues. These nonlinear relationships explain how sampling bias from different ends of the nonlinear curves can result in conflicting trait relationships. Further, the shape of the relationships varies depending on evolutionary context and mycorrhizal affiliation. Importantly, the observed nonlinear trait relationships do not support the RES predictions. Allometry-based nonlinearity of root trait relationships improves our understanding of the ecology, physiology and evolution of absorptive roots.


Assuntos
Evolução Biológica , Raízes de Plantas/genética , Plantas/genética , Característica Quantitativa Herdável , Conjuntos de Dados como Assunto , Dinâmica não Linear , Fenótipo , Filogenia , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/metabolismo , Plantas/anatomia & histologia , Plantas/metabolismo
17.
Environ Monit Assess ; 191(6): 387, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31115704

RESUMO

Phytoplankton and epipelon assemblages form the main constituents, and they are producers in aquatic ecosystems, such as streams and rivers. This study was carried out between May 2008 and April 2009 to determine the impacts of polluted water on species variations, compositions, and community metrics in phytoplankton and epipelon at six stations on Ankara Stream. A total of 231 taxa were recorded during the study period, with 131 Bacillariophyta, 3 Charophyta, 41 Chlorophyta, 30 Cyanobacteria, 25 Euglenophyta, and 1 Ochrophyta. Heterogeneity of the stream stations was determined by the use of hierarchical cluster analysis (HCA). Community metrics were compared by using non-parametric tests, while canonical correspondence analysis (CCA) was used for the relationships between environmental variables and species. Variations in water quality and species composition along the stream flow revealed a significant spatial heterogeneity (p < 0.05). However, the upper stations of the stream were represented by unpolluted water quality with low nutrients and conductivity, and the mid- and downstream stations were characterized by high concentrations of ammonia (up to 60 mg L-1) and o-phosphate (up to 25 mg/L), with low concentrations of dissolved oxygen (< 1 mg L-1). The results, clearly supported by indicator taxa, showed that various domestic and industrial discharges affected the increase in pollution and the spatial heterogeneity. The findings obtained in this study will contribute to future improvements in Ankara Stream watershed studies.


Assuntos
Diatomáceas/metabolismo , Monitoramento Ambiental/métodos , Resíduos Industriais/análise , Fitoplâncton/metabolismo , Plantas/metabolismo , Rios/química , Poluição da Água/efeitos adversos , Poluição da Água/análise , Amônia/análise , Biodiversidade , Cianobactérias/classificação , Cianobactérias/metabolismo , Ecossistema , Euglênidos/metabolismo , Oxigênio/análise , Fosfatos/análise , Plantas/classificação , Turquia , Qualidade da Água
18.
Nat Commun ; 10(1): 2142, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-31086174

RESUMO

Metabolic engineers endeavor to create a bio-based manufacturing industry using microbes to produce fuels, chemicals, and medicines. Plant natural products (PNPs) are historically challenging to produce and are ubiquitous in medicines, flavors, and fragrances. Engineering PNP pathways into new hosts requires finding or modifying a suitable host to accommodate the pathway, planning and implementing a biosynthetic route to the compound, and discovering or engineering enzymes for missing steps. In this review, we describe recent developments in metabolic engineering at the level of host, pathway, and enzyme, and discuss how the field is approaching ever more complex biosynthetic opportunities.


Assuntos
Produtos Biológicos/metabolismo , Engenharia Metabólica/métodos , Microrganismos Geneticamente Modificados/metabolismo , Plantas/metabolismo , Vias Biossintéticas/genética , Enzimas/genética , Enzimas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Engenharia Metabólica/tendências , Microrganismos Geneticamente Modificados/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Biologia Sintética/métodos , Biologia Sintética/tendências
19.
J Agric Food Chem ; 67(21): 5949-5956, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31050427

RESUMO

Odorant binding proteins (OBPs) are considered to be highly expressed at antennae sensillum lymph and play crucial roles in detection of insect host plant volatiles. The polyphagous mirid bug Apolygus lucorum is one of a series of insect pests on many important agricultural crops that heavily rely on sophisticated olfaction to locate host plants. Previously, putative OBP genes and their tissue-related expression patterns in this pest species have been clarified. In this study, we characterized the ligand spectrum and the molecular binding mechanism of the antennae-biased AlucOBP22 to host plant volatiles of A. lucorum. Frist, the recombinant AlucOBP22 protein was constructed and purified, and its binding affinities to selected host plant volatiles were assessed. Two terpenoids, ß-ionone and ß-caryophyllene, could highly bind to AlucOBP22. Next, three-dimensional model prediction indicated that AlucOBP22 employed six α-helices to form a typical pocket for ligand accommodation. Molecular docking analysis suggested that both ß-ionone and ß-caryophyllene were located at the AlucOBP22 pocket with some hydrophobic amino acid residues close to the two chemicals, suggesting that hydrophobic interactions might be crucial for ligand-specific binding. Finally, site-directed mutagenesis combined with fluorescence binding assays revealed that mutants of five hydrophobic residues Leu5, Ile40, Met41, Val44, and Met45 displayed significantly decreased or completely abolished binding affinities to the two ligands. Our findings showed the specific binding characteristic of AlucOBP22 and suggested that hydrophobic residues and their hydrophobic interactions were involved in AlucOBP22 binding to terpenoids, which provided new insights into the molecular interaction mechanisms of hemipteran insect OBPs to host plant odors.


Assuntos
Heterópteros/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Plantas/metabolismo , Receptores Odorantes/química , Receptores Odorantes/metabolismo , Terpenos/química , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Heterópteros/química , Heterópteros/genética , Interações Hidrofóbicas e Hidrofílicas , Proteínas de Insetos/genética , Simulação de Acoplamento Molecular , Plantas/química , Plantas/parasitologia , Ligação Proteica , Receptores Odorantes/genética , Terpenos/metabolismo
20.
Cell Mol Life Sci ; 76(18): 3525-3542, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31101936

RESUMO

While scientific advances have led to large-scale production and widespread distribution of vaccines and antiviral drugs, viruses still remain a major cause of human diseases today. The ever-increasing reports of viral resistance and the emergence and re-emergence of viral epidemics pressure the health and scientific community to constantly find novel molecules with antiviral potential. This search involves numerous different approaches, and the use of antimicrobial peptides has presented itself as an interesting alternative. Even though the number of antimicrobial peptides with antiviral activity is still low, they already show immense potential to become pharmaceutically available antiviral drugs. Such peptides can originate from natural sources, such as those isolated from mammals and from animal venoms, or from artificial sources, when bioinformatics tools are used. This review aims to shed some light on antimicrobial peptides with antiviral activities against human viruses and update the data about the already well-known peptides that are still undergoing studies, emphasizing the most promising ones that may become medicines for clinical use.


Assuntos
Antivirais/química , Peptídeos/química , Anfíbios/metabolismo , Animais , Antivirais/metabolismo , Antivirais/farmacologia , Artrópodes/metabolismo , Vírus da Dengue/efeitos dos fármacos , HIV/efeitos dos fármacos , Humanos , Peptídeos/metabolismo , Peptídeos/farmacologia , Plantas/metabolismo , Simplexvirus/efeitos dos fármacos
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