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1.
J Mol Evol ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513601

RESUMO

The ATP-binding cassette (ABC) transporter gene family is ubiquitous in the living world. ABC proteins bind and hydrolyze ATP to transport a myriad of molecules across various lipid-containing membrane systems. They have been studied well in plants for transport of a variety of compounds and particularly, in vertebrates due to their direct involvement in resistance mechanisms against several toxic molecules/metabolites. ABC transporters in insects are found within large multigene families involved in the efflux of chemical insecticides and toxic/undesired metabolites originating from food and endogenous metabolism. This review deals with ABC transporter subfamilies of few agronomically important Lepidopteran pests. The transcriptional dynamics and regulation of ABC transporters during insect development emphasizes their functional diversity against insecticides, Cry toxins, and plant specialized metabolites. To generate insights about molecular function and physiological roles of ABCs, functional and structural characterization is necessary. Also, expansion and divergence of ABC transporter gene subfamilies in Lepidopteran insects needs more systematic investigation. We anticipate that newer methods of insect control in agriculture can benefit from an understanding of ABC transporter interactions with a vast range of natural specialized molecules and synthetic compounds.

2.
New Phytol ; 234(4): 1394-1410, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35238413

RESUMO

Solanum steroidal glycoalkaloids (SGAs) are renowned defence metabolites exhibiting spectacular structural diversity. Genes and enzymes generating the SGA precursor pathway, SGA scaffold and glycosylated forms have been largely identified. Yet, the majority of downstream metabolic steps creating the vast repertoire of SGAs remain untapped. Here, we discovered that members of the 2-OXOGLUTARATE-DEPENDENT DIOXYGENASE (2-ODD) family play a prominent role in SGA metabolism, carrying out three distinct backbone-modifying oxidative steps in addition to the three formerly reported pathway reactions. The GLYCOALKALOID METABOLISM34 (GAME34) enzyme catalyses the conversion of core SGAs to habrochaitosides in wild tomato S. habrochaites. Cultivated tomato plants overexpressing GAME34 ectopically accumulate habrochaitosides. These habrochaitoside enriched plants extracts potently inhibit Puccinia spp. spore germination, a significant Solanaceae crops fungal pathogen. Another 2-ODD enzyme, GAME33, acts as a desaturase (via hydroxylation and E/F ring rearrangement) forming unique, yet unreported SGAs. Conversion of bitter α-tomatine to ripe fruit, nonbitter SGAs (e.g. esculeoside A) requires two hydroxylations; while the known GAME31 2-ODD enzyme catalyses hydroxytomatine formation, we find that GAME40 catalyses the penultimate step in the pathway and generates acetoxy-hydroxytomatine towards esculeosides accumulation. Our results highlight the significant contribution of 2-ODD enzymes to the remarkable structural diversity found in plant steroidal specialized metabolism.


Assuntos
Alcaloides , Dioxigenases , Lycopersicon esculentum , Solanum tuberosum , Solanum , Alcaloides/metabolismo , Dioxigenases/genética , Dioxigenases/metabolismo , Ácidos Cetoglutáricos/metabolismo , Lycopersicon esculentum/genética , Solanum/genética , Solanum/metabolismo , Solanum tuberosum/genética
3.
Microb Ecol ; 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34977966

RESUMO

Entomopathogenic fungi offer an effective and eco-friendly alternative to curb insect populations in biocontrol strategy. The evolutionary history of selected entomopathogenic fungi indicates their ancestral relationship with plant endophytes. During this host shifting, entomopathogenic fungi must have acquired multiple mechanisms, including a combination of various biomolecules that make them distinguishable from other fungi. In this review, we focus on understanding various biochemical and molecular mechanisms involved in entomopathogenesis. In particular, we attempt to explain the indispensable role of enlarged gene families of various virulent factors, viz. chitinases, proteases, lipases, specialized metabolites, and cytochrome P450, in entomopathogenesis. Our analysis suggests that entomopathogenic fungi recruit a different set of gene products during the progression of pathogenesis. Knowledge of these bio-molecular interactions between fungi and insect hosts will allow researchers to execute pointed efforts towards the development of improved entomopathogenic fungal strains.

4.
New Phytol ; 233(3): 1220-1237, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34758118

RESUMO

Steroidal glycoalkaloids (SGAs) are protective metabolites constitutively produced by Solanaceae species. Genes and enzymes generating the vast structural diversity of SGAs have been largely identified. Yet, mechanisms of hormone pathways coordinating defence (jasmonate; JA) and growth (gibberellin; GA) controlling SGAs metabolism remain unclear. We used tomato to decipher the hormonal regulation of SGAs metabolism during growth vs defence tradeoff. This was performed by genetic and biochemical characterisation of different JA and GA pathways components, coupled with in vitro experiments to elucidate the crosstalk between these hormone pathways mediating SGAs metabolism. We discovered that reduced active JA results in decreased SGA production, while low levels of GA or its receptor led to elevated SGA accumulation. We showed that MYC1 and MYC2 transcription factors mediate the JA/GA crosstalk by transcriptional activation of SGA biosynthesis and GA catabolism genes. Furthermore, MYC1 and MYC2 transcriptionally regulate the GA signalling suppressor DELLA that by itself interferes in JA-mediated SGA control by modulating MYC activity through protein-protein interaction. Chemical and fungal pathogen treatments reinforced the concept of JA/GA crosstalk during SGA metabolism. These findings revealed the mechanism of JA/GA interplay in SGA biosynthesis to balance the cost of chemical defence with growth.


Assuntos
Alcaloides , Lycopersicon esculentum , Alcaloides/metabolismo , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Giberelinas/metabolismo , Lycopersicon esculentum/metabolismo , Oxilipinas/metabolismo
5.
Plant Sci ; 314: 111120, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34895549

RESUMO

Little is known about how different plant-based diets influence the insect herbivores' oral secretion (OS) composition and eventually the plant defense responses. We analyzed the OS composition of the generalist Lepidopteran insect, Helicoverpa armigera feeding on the host plant tomato (OSH), non-host plant capsicum (OSNH), and artificial diet (OSAD) using Liquid Chromatography-Quadrupole Time of Flight Mass Spectrometry. Higher numbers and levels of alkaloids and terpenoids were observed in OSH and OSNH, respectively while OSAD was rich in phospholipids. Interestingly, treatment of H. armigera OSAD, OSH and OSNH on wounded tomato leaves showed differential expression of (i) genes involved in JA and SA biosynthesis and their responsive genes, and (ii) biosynthetic pathway genes of chlorogenic acid (CGA) and trehalose, which exhibited increased accumulation along with several other plant defensive metabolites. Specifically, high levels of CGA were detected after OSH and OSNH treatments in tomato leaves. There was higher expression of the genes involved in phenylpropanoid biosynthesis, which may lead to the increased accumulation of CGA and related metabolites. In the insect bioassay, CGA significantly inhibited H. armigera larval growth. Our results underline the differential accumulation of plant and insect OS metabolites and identified potential plant metabolite(s) affecting insect growth and development.


Assuntos
Secreções Corporais/química , Dieta , Herbivoria/fisiologia , Interações Hospedeiro-Parasita/fisiologia , Lepidópteros/fisiologia , Lycopersicon esculentum/parasitologia , Defesa das Plantas contra Herbivoria/fisiologia , Animais
6.
Phytochemistry ; 193: 113008, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34768189

RESUMO

For more than 350 million years, there have been ongoing dynamic interactions between plants and insects. In several cases, insects cause-specific feeding damage with ensuing herbivore-associated molecular patterns that invoke characteristic defense responses. During feeding on plant tissue, insects release oral secretions (OSs) containing a repertoire of molecules affecting plant defense (effectors). Some of these OS components might elicit a defense response to combat insect attacks (elicitors), while some might curb the plant defenses (suppressors). Few reports suggest that the synthesis and function of OS components might depend on the host plant and associated microorganisms. We review these intricate plant-insect interactions, during which there is a continuous exchange of molecules between plants and feeding insects along with the associated microorganisms. We further provide a list of commonly identified inducible plant produced defensive molecules released upon insect attack as well as in response to OS treatments of the plants. Thus, we describe how plants specialized and defense-related metabolism is modulated at innumerable phases by OS during plant-insect interactions. A molecular understanding of these complex interactions will provide a means to design eco-friendly crop protection strategies.


Assuntos
Herbivoria , Plantas , Animais , Insetos
7.
Phytochem Rev ; : 1-35, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34366748

RESUMO

Ocimum species represent commercially important medicinal and aromatic plants. The essential oil biosynthesized by Ocimum species is enriched with specialized metabolites specifically, terpenoids and phenylpropanoids. Interestingly, various Ocimum species are known to exhibit diverse chemical profiles, and this chemical diversity has been at the center of many studies to identify commercially important chemotypes. Here, we present various chemotypes from the Ocimum species and emphasize trends, implications, and strategies for the quality and yield improvement of essential oil. Globally, many Ocimum species have been analyzed for their essential oil composition in over 50 countries. Asia represents the highest number of chemotypes, followed by Africa, South America, and Europe. Ocimum basilicum L. has been the most widespread and well-studied species, followed by O. gratissimum L., O. tenuiflorum L., O. canum Sims, O. americanum and O. kilimandscharicum Gürke. Moreover, various molecular reasons, benefits, adverse health effects and mechanisms behind this vast chemodiversity have been discussed. Different strategies of plant breeding, metabolic engineering, transgenic, and tissue-culture, along with anatomical modifications, are surveyed to enhance specific chemotypic profiles and essential oil yield in numerous Ocimum species. Consequently, chemical characterization of the essential oil obtained from Ocimum species has become indispensable for its proper utilization. The present chemodiversity knowledge from Ocimum species will help to exploit various applications in the industrial, agriculture, biopharmaceutical, and food sectors. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s11101-021-09767-z.

8.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204857

RESUMO

Phytochemicals belonging to the group of alkaloids are signature specialized metabolites endowed with countless biological activities. Plants are armored with these naturally produced nitrogenous compounds to combat numerous challenging environmental stress conditions. Traditional and modern healthcare systems have harnessed the potential of these organic compounds for the treatment of many ailments. Various chemical entities (functional groups) attached to the central moiety are responsible for their diverse range of biological properties. The development of the characterization of these plant metabolites and the enzymes involved in their biosynthesis is of an utmost priority to deliver enhanced advantages in terms of biological properties and productivity. Further, the incorporation of whole/partial metabolic pathways in the heterologous system and/or the overexpression of biosynthetic steps in homologous systems have both become alternative and lucrative methods over chemical synthesis in recent times. Moreover, in-depth research on alkaloid biosynthetic pathways has revealed numerous chemical modifications that occur during alkaloidal conversions. These chemical reactions involve glycosylation, acylation, reduction, oxidation, and methylation steps, and they are usually responsible for conferring the biological activities possessed by alkaloids. In this review, we aim to discuss the alkaloidal group of plant specialized metabolites and their brief classification covering major categories. We also emphasize the diversity in the basic structures of plant alkaloids arising through enzymatically catalyzed structural modifications in certain plant species, as well as their emerging diverse biological activities. The role of alkaloids in plant defense and their mechanisms of action are also briefly discussed. Moreover, the commercial utilization of plant alkaloids in the marketplace displaying various applications has been enumerated.


Assuntos
Alcaloides/química , Alcaloides/metabolismo , Fenômenos Fisiológicos Vegetais , Plantas/química , Acilação , Alcaloides/farmacologia , Vias Biossintéticas , Glicosilação , Metilação , Estrutura Molecular , Oxirredução , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia
9.
BMC Plant Biol ; 21(1): 267, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34107869

RESUMO

BACKGROUND: Serine protease inhibitors belonging to the Potato type-II Inhibitor family Protease Inhibitors (Pin-II type PIs) are essential plant defense molecules. They are characterized by multiple inhibitory repeat domains, conserved disulfide bond pattern, and a tripeptide reactive center loop. These features of Pin-II type PIs make them potential molecules for protein engineering and designing inhibitors for agricultural and therapeutic applications. However, the diversity in these PIs remains unexplored due to the lack of annotated protein sequences and their functional attributes in the available databases. RESULTS: We have developed a database, PINIR (Pin-II type PIs Information Resource), by systematic collection and manual annotation of 415 Pin-II type PI protein sequences. For each PI, the number and position for signature sequences are specified: 695 domains, 75 linkers, 63 reactive center loops, and 10 disulfide bond patterns are identified and mapped. Database analysis revealed novel subcategories of PIs, species-correlated occurrence of inhibitory domains, reactive center loops, and disulfide bond patterns. By analyzing linker regions, we predict that alternative processing at linker regions could generate PI variants in the Solanaceae family. CONCLUSION: PINIR ( https://pinir.ncl.res.in ) provides a web interface for browsing and analyzing the protein sequences of Pin-II type PIs. Information about signature sequences, spatio-temporal expression, biochemical properties, gene sequences, and literature references are provided. Analysis of PINIR depicts conserved species-specific features of Pin-II type PI protein sequences. Diversity in the sequence of inhibitory domains and reactive loops directs potential applications to engineer Pin-II type PIs. The PINIR database will serve as a comprehensive information resource for further research into Pin-II type PIs.


Assuntos
Sequência de Aminoácidos , Bases de Dados como Assunto , Resistência à Doença/genética , Genes de Plantas , Proteínas de Plantas/genética , Inibidores de Serino Proteinase/genética
10.
Plant Sci ; 306: 110854, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33775360

RESUMO

Many tuber and storage root crops owing to their high nutritional values offer high potential to overcome food security issues. The lack of information regarding molecular mechanisms that govern belowground storage organ development (except a tuber crop, potato) has limited the application of biotechnological strategies for improving storage crop yield. Phytohormones like gibberellin and cytokinin are known to play a crucial role in governing potato tuber development. Another phytohormone, auxin has been shown to induce tuber initiation and growth, and its crosstalk with gibberellin and strigolactone in a belowground modified stem (stolon) contributes to the overall potato tuber yield. In this review, we describe the crucial role of auxin biology in development of potato tubers. Considering the emerging reports from commercially important storage root crops (sweet potato, cassava, carrot, sugar beet and radish), we propose the function of auxin and related gene regulatory network in storage root development. The pattern of auxin content of stolon during various stages of potato tuber formation appears to be consistent with its level in various developmental stages of storage roots. We have also put-forward the potential of three-way interaction between auxin, strigolactone and mycorrhizal fungi in tuber and storage root development. Overall, we propose that auxin gene regulatory network and its crosstalk with other phytohormones in stolons/roots could govern belowground tuber and storage root development.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Organogênese Vegetal/efeitos dos fármacos , Reguladores de Crescimento de Plantas/metabolismo , Tubérculos/crescimento & desenvolvimento , Tubérculos/metabolismo , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Organogênese Vegetal/genética , Tubérculos/genética , Plantas Geneticamente Modificadas , Solanum tuberosum/genética
11.
Int J Biol Macromol ; 181: 202-210, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33774069

RESUMO

Plant 4-coumarate-CoA ligase (4CL) catalyzes the ligation of CoA to cinnamic acid and its derivatives. Activated CoA esters are utilized for the biosynthesis of phenolic metabolites and lignin that play essential function in plants. Here, we characterize the diversity of Ocimum kilimandscharicum 4CLs (Ok4CLs). Phylogenetic analysis suggest that Ok4CLs could be grouped into three classes, class I - enzymes mostly involved in lignin biosynthesis, class II - non-structural phenylpropanoid biosynthesis and class III - yet to be characterized for specific role(s). We selected two Ok4CLs namely Ok4CL7 and Ok4CL15 for further characterization. Gene expression analysis suggested that Ok4CL7 is highly expressed in leaf trichomes, whereas Ok4CL15 is abundant in the roots. The recombinant Ok4CL7 and Ok4CL15 had optimal enzyme activities at 40 °C in pH 8 and 7, respectively. Ok4CL7 showed substrate preference towards p-coumaric acid, ferulic acid and caffeic acid. While, Ok4CL15 preferred p-coumaric acid, ferulic acid and sinapic acid. Feruloyl adenylate showed higher number of contacts and lowers binding energy with Ok4CL7 and 15 compared to cinnamoyl adenylate. Based on root-specific expression and preference for sinapic acid, Ok4CL15 might be involved in lignin biosynthesis. Further exploration is needed to unravel the role of diverse Ok4CLs in O. kilimandscharicum.


Assuntos
Vias Biossintéticas , Coenzima A Ligases/metabolismo , Ocimum/enzimologia , Proteínas de Plantas/metabolismo , Propanóis/metabolismo , Sítios de Ligação , Vias Biossintéticas/genética , Coenzima A Ligases/química , Coenzima A Ligases/genética , Sequência Conservada , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ocimum/genética , Especificidade de Órgãos/genética , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Domínios Proteicos , Proteínas Recombinantes/metabolismo , Especificidade por Substrato
12.
Planta ; 253(2): 61, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33538903

RESUMO

MAIN CONCLUSION: During the process of plant domestication, the selection and traditional breeding for desired characters such as flavor, juiciness and nutritional value of fruits, probably have resulted in gain or loss of specialized metabolites contributing to these traits. Their appearance in fruits is likely due to the acquisition of novel and specialized metabolic pathways and their regulation, driven by systematic molecular evolutionary events facilitated by traditional breeding. Plants change their armory of specialized metabolism to adapt and survive in diverse ecosystems. This may occur through molecular evolutionary events, such as single nucleotide polymorphism, gene duplication and transposition, leading to convergent or divergent evolution of biosynthetic pathways producing such specialized metabolites. Breeding and selection for improved specific and desired traits (fruit size, color, taste, flavor, etc.) in fruit crops through conventional breeding approaches may further alter content and profile of specialized metabolites. Biosynthetic routes of these metabolites have been studied in various plants. Here, we explore the influence of plant domestication and breeding processes on the selection of biosynthetic pathways of favorable specialized metabolites in fruit crops. An orderly clustered arrangement of genes associated with their production is observed in many fruit crops. We further analyzed selection-based acquisition of specialized metabolic pathways comparing first the metabolic profiles and genes involved in their biosynthesis, followed by the genomic organization of such genes between wild and domesticated horticultural crops. Domestication of crop plants favored the acquisition and retention of metabolic pathways that enhanced the fruit value while eliminated those which produced toxic or unfavorable metabolites. Interestingly, unintentional reorganization of complex metabolic pathways by selection and traditional breeding processes has endowed us with flavorful, juicy and nutritionally rich fruits.


Assuntos
Produtos Agrícolas/metabolismo , Domesticação , Frutas , Redes e Vias Metabólicas , Melhoramento Vegetal , Produtos Agrícolas/genética , Ecossistema , Frutas/genética , Frutas/metabolismo
13.
J Biomol Struct Dyn ; 39(9): 3099-3114, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32329408

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has resulted in the current COVID-19 pandemic. Worldwide this disease has infected over 2.5 million individuals with a mortality rate ranging from 5 to 10%. There are several efforts going on in the drug discovery to control the SARS-CoV-2 viral infection. The main protease (MPro) plays a critical role in viral replication and maturation, thus can serve as the primary drug target. To understand the structural evolution of MPro, we have performed phylogenetic and Sequence Similarity Network analysis, that depicted divergence of Coronaviridae MPro in five clusters specific to viral hosts. This clustering was corroborated with the comparison of MPro structures. Furthermore, it has been observed that backbone and binding site conformations are conserved despite variation in some of the residues. These attributes can be exploited to repurpose available viral protease inhibitors against SARS-CoV-2 MPro. In agreement with this, we performed screening of ∼7100 molecules including active ingredients present in the Ayurvedic anti-tussive medicines, anti-viral phytochemicals and synthetic anti-virals against SARS-CoV-2 MPro as the primary target. We identified several natural molecules like δ-viniferin, myricitrin, taiwanhomoflavone A, lactucopicrin 15-oxalate, nympholide A, afzelin, biorobin, hesperidin and phyllaemblicin B that strongly binds to SARS-CoV-2 MPro. Intrestingly, these molecules also showed strong binding with other potential targets of SARS-CoV-2 infection like viral receptor human angiotensin-converting enzyme 2 (hACE-2) and RNA dependent RNA polymerase (RdRp). We anticipate that our approach for identification of multi-target-directed ligand will provide new avenues for drug discovery against SARS-CoV-2 infection.Communicated by Ramaswamy H. Sarma.


Assuntos
COVID-19 , Preparações Farmacêuticas , Humanos , Ligantes , Pandemias , Peptídeo Hidrolases , Filogenia , Inibidores de Proteases/farmacologia , SARS-CoV-2
14.
Front Plant Sci ; 12: 800030, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35003188

RESUMO

Root-knot nematodes (RKNs) are notorious plant-parasitic nematodes first recorded in 1855 in cucumber plants. They are microscopic, obligate endoparasites that cause severe losses in agriculture and horticulture. They evade plant immunity, hijack the plant cell cycle, and metabolism to modify healthy cells into giant cells (GCs) - RKN feeding sites. RKNs secrete various effector molecules which suppress the plant defence and tamper with plant cellular and molecular biology. These effectors originate mainly from sub-ventral and dorsal oesophageal glands. Recently, a few non-oesophageal gland secreted effectors have been discovered. Effectors are essential for the entry of RKNs in plants, subsequently formation and maintenance of the GCs during the parasitism. In the past two decades, advanced genomic and post-genomic techniques identified many effectors, out of which only a few are well characterized. In this review, we provide molecular and functional details of RKN effectors secreted during parasitism. We list the known effectors and pinpoint their molecular functions. Moreover, we attempt to provide a comprehensive insight into RKN effectors concerning their implications on overall plant and nematode biology. Since effectors are the primary and prime molecular weapons of RKNs to invade the plant, it is imperative to understand their intriguing and complex functions to design counter-strategies against RKN infection.

15.
Int J Biol Macromol ; 163: 1444-1450, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32735926

RESUMO

α-Amylase inhibitors (α-AIs) target α-amylases and interfere with the carbohydrate digestion of insects. Among different classes of α-AIs, a knottin-type inhibitor from Amaranthus hypochondriacus (AhAI) was found to be specific against coleopteran storage pests. In this report, we have characterized three previously unidentified knottin-type α-AIs from various Amaranthaceae plants namely, Amaranthus hypochondriacus (AhAI2), Alternanthera sessilis (AsAI) and Chenopodium quinoa (CqAI). They contain a signal peptide, pro-peptide, and mature peptide. The mature peptides of the new α-AIs shared 68 to 78% identity with AhAI and have highly variable pro-peptide regions. Along with the cystine-knot fold, they showed conservation of reactive site residues. All recombinant α-AIs were successfully expressed in their active form and native state using an oxidative cytoplasmic environment. Inhibition studies against various amylases revealed that these inhibitors showed selective inhibition of coleopteran recombinant insect α-amylases viz., Tribolium castaneum, and Callosobruchus chinensis. Tribolium castaneum α-amylase inhibition potency was highest for AhAI2 (Ki ~ 15 µM) followed by AsAI (Ki ~ 43 µM) and CqAI (Ki ~ 61 µM). Interaction analysis of these inhibitors illustrated that the reactive site of inhibitors make several non-covalent interactions with the substrate-binding pocket of coleopteran α-amylases. The selectivity of these inhibitors against coleopteran α-amylases highlights their potential in storage grain pest control.


Assuntos
Amaranthaceae/química , Amaranthus/química , Besouros/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , alfa-Amilases/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Besouros/metabolismo , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Insetos/efeitos dos fármacos , Insetos/metabolismo , Peptídeos/química , Proteínas de Plantas/química , Tribolium/metabolismo
16.
Mol Biotechnol ; 62(10): 508-520, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32844356

RESUMO

Globally farmers have difficulty in extending the shelf-life of the tropical fruits due to their perishable nature. The present study aimed to assess the effect of hexanal nano-formulation treatment (NFT) on the shelf-life of Alphonso mango. Further, volatilomics was performed to explore the molecular basis of such effect. Untreated and treated fruits were sampled starting from 5th to 21st day after NFT at an interval of 4 days. Moderate changes in visual and digital colour parameters were evident from the intact and dissected fruits of NFT set compared to untreated fruits. Biochemical assays affirmed the phenotypic differences with significant changes in the colour imparting compounds like carotenoids and anthocyanins among them. Further, gas chromatography-mass spectrometry analysis revealed significant qualitative and quantitative variations in the different classes of compounds like lactones, furanones, esters, aldehydes and alcohols. Some of the key metabolites showed differential modulations among the NFT and untreated fruit sets indicating their potential role in various processes, which ultimately might have resulted in delayed ripening of the mango. Overall, this study has demonstrated the beneficial effect of hexanal and identified important metabolites with the enhanced shelf-life in Alphonso that could be useful for farmers and mango-based food/flavour industries.


Assuntos
Armazenamento de Alimentos , Frutas/metabolismo , Mangifera/metabolismo , Metaboloma , Análise por Conglomerados , Cor , Nanotecnologia , Fenótipo , Pigmentação , Análise de Componente Principal , Espectrofotometria
17.
Biochim Biophys Acta Gen Subj ; 1864(12): 129703, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32805319

RESUMO

BACKGROUND: α-Amylase inhibitors (α-AIs) belong to the discrete classes, and exhibited differential specificities against α-amylases from various sources. Several α-amylases and their complexes with inhibitors at the molecular level have been studied in detail. Interestingly, some α-AIs depict specific and selective interactions amid different insect α-amylases. SCOPE OF REVIEW: There are studies to understand evolutionary variability and functional differentiation of insect α-amylases and their cognate inhibitors. We have examined sequence, structural, and interaction diversity between various α-amylases and α-AIs. Based on these analyses, we are providing a potential basis for the functional differentiation among certain insect α-amylases concerning mammalian counterparts and their interactions with different proteinaceous α-AIs. MAJOR CONCLUSIONS: Insect α-amylases have conserved domain architecture with differences in length, number of disulfide bonds, and secondary structure. Furthermore, few of them exhibit variable characteristics like chloride dependent activity, the presence of N-terminal glutamine residue to protect against proteolytic degradation, and loop variations near the enzyme active site. Conformation of α-AI protein could be an essential factor for their specificity and binding affinities towards target α-amylase(s). Furthermore, variation into the enzyme binding pocket residues might contribute to differential interactions with inhibitors. GENERAL SIGNIFICANCE: Molecular insights in the interactions between insect α-amylases and plant α-AI will provide the details of mechanisms assisting the inhibitor specificity. Furthermore, this information will help to design potent and effective α-AIs against specific α-amylase.


Assuntos
alfa-Amilases/metabolismo , Sequência de Aminoácidos , Animais , Evolução Molecular , Herbivoria , Humanos , Insetos/química , Insetos/enzimologia , Insetos/metabolismo , Modelos Moleculares , Plantas/química , Plantas/enzimologia , Plantas/metabolismo , Conformação Proteica , Proteólise , Alinhamento de Sequência , Especificidade por Substrato , alfa-Amilases/química
18.
Phytochemistry ; 177: 112451, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32619737

RESUMO

In Ocimum kilimandscharicum, the relative volatile composition of camphor in leaves was as high as 55%, while that of eugenol in roots was 57%. These metabolites were differentially partitioned between the aerial and root tissues. Global metabolomics revealed tissue-specific biochemical specialization, evident by the differential distribution of 2588 putative metabolites across nine tissues. Next-generation sequencing analysis indicated differential expression of 51 phenylpropanoid and 55 terpenoid pathway genes in aerial and root tissues. By integrating metabolomics with transcriptomics, the camphor biosynthesis pathway in O. kilimandscharicum was elucidated. In planta bioassays revealed the role of geranyl diphosphate synthase (gpps) and borneol dehydrogenase (bdh) in camphor biosynthesis. Further, the partitioning of camphor was attributed to tissue-specific gene expression of both the pathway entry point (gpps) and terminal (bdh) enzyme. Unlike camphor, eugenol accumulated more in roots; however, absence of the eugenol synthase gene in roots indicated long distance transport from aerial tissues. In silico co-expression analysis indicated the potential involvement of ATP-binding cassette, multidrug and toxic compound extrusion, and sugar transporters in eugenol transport. Similar partitioning was evident across five other Ocimum species. Overall, our work indicates that metabolite partitioning maybe a finely regulated process, which may have implications on plant growth, development, and defense.


Assuntos
Ocimum basilicum , Ocimum , Óleos Voláteis , Cânfora , Eugenol
19.
J Biomol Struct Dyn ; 38(5): 1388-1397, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31038412

RESUMO

Although several plant protease inhibitors have been structurally characterized using X-ray crystallography, very few have been studied using NMR techniques. Here, we report an NMR study of the solution structure and dynamics of an inhibitory repeat domain (IRD) variant 12 from the wound-inducible Pin-II type proteinase inhibitor from Capsicum annuum. IRD variant 12 (IRD12) showed strong anti-metabolic activity against the Lepidopteran insect pest, Helicoverpa armigera. The NMR-derived three-dimensional structure of IRD12 reveals a three-stranded anti-parallel ß-sheet rigidly held together by four disulfide bridges and shows structural homology with known IRDs. It is interesting to note that the IRD12 structure containing ∼75% unstructured part still shows substantial amount of rigidity of N-H bond vectors with respect to its molecular motion.Communicated by Ramaswamy H. Sarma.


Assuntos
Capsicum , Mariposas , Animais , Capsicum/genética , Insetos , Proteínas de Plantas/genética , Inibidores de Proteases/farmacologia
20.
Planta ; 251(1): 28, 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31802261

RESUMO

MAIN CONCLUSION: Exploration with high-throughput transcriptomics and metabolomics of two varieties of Ceropegia bulbosa identifies candidate genes, crucial metabolites and a potential cerpegin biosynthetic pathway. Ceropegia bulbosa is an important medicinal plant, used in the treatment of various ailments including diarrhea, dysentery, and syphilis. This is primarily attributed to the presence of pharmaceutically active secondary metabolites, especially cerpegin. As this plant belongs to an endemic threatened category, genomic resources are not available hampering exploration on the molecular basis of cerpegin accumulation till now. Therefore, we undertook high-throughput metabolomic and transcriptomic analyses using different tissues from two varieties namely, C. bulbosa var. bulbosa and C. bulbosa var. lushii. Metabolomic analysis revealed spatial and differential accumulation of various metabolites. We chemically synthesized and characterized the cerpegin and its derivatives by liquid chromatography tandem-mass spectrometry (LC-MS/MS). Importantly, these comparisons suggested the presence of cerpegin and 5-allyl cerpegin in all C. bulbosa tissues. Further, de novo transcriptome analysis indicated the presence of significant transcripts for secondary metabolic pathways through the Kyoto encyclopedia of genes and genomes database. Tissue-specific profiling of transcripts and metabolites showed a significant correlation, suggesting the intricate mechanism of cerpegin biosynthesis. The expression of potential candidate genes from the proposed cerpegin biosynthetic pathway was further validated by qRT-PCR and NanoString nCounter. Overall, our findings propose a potential route of cerpegin biosynthesis. Identified transcripts and metabolites have built a foundation as new molecular resources that could facilitate future research on biosynthesis, regulation, and engineering of cerpegin or other important metabolites in such non-model plants.


Assuntos
Apocynaceae/genética , Apocynaceae/metabolismo , Vias Biossintéticas/genética , Perfilação da Expressão Gênica , Metabolômica , Piridonas/metabolismo , Flores/genética , Regulação da Expressão Gênica de Plantas , Metaboloma , Anotação de Sequência Molecular , Especificidade de Órgãos/genética , Análise de Componente Principal , Piridonas/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
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