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1.
Food Chem ; 367: 130701, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34388635

RESUMO

Carotenoids are colored compounds with important physiological functions. The Haida golden scallop, which has an orange adductor muscle, is a carotenoid-enriched variety of scallop Mizuhopecten yessoensis, an important aquaculture shellfish. In this study, we investigated the tissue distribution of the carotenoids, pectenolone and pectenoxanthin, in both Haida golden scallop and normal Yesso scallop. Both carotenoids were detected in all the sampled tissues of the two scallops, except in the adductor muscle of normal scallop. There were significantly more carotenoids in Haida golden scallop than in normal scallop, in the tissues of the mantle, female gonad, kidney, and adductor muscle. Increased carotenoid concentrations were detected in Haida golden scallop adductor muscle during the spring spawning season, indicating the effects of reproduction on muscle carotenoids accumulation. This study was the first systematic investigation of carotenoid distribution in Yesso scallop tissues and will benefit future research on carotenoid accumulation and function in scallops.


Assuntos
Citrus sinensis , Pectinidae , Animais , Carotenoides/metabolismo , Citrus sinensis/metabolismo , Músculo Esquelético/metabolismo , Pectinidae/metabolismo , Estações do Ano , Distribuição Tecidual
2.
Gene ; 806: 145929, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34461150

RESUMO

The body color of Neocaridina denticulate sinensis is a compelling phenotypic trait, in which a cascade of carotenoid metabolic processes plays an important role. The study was conducted to compare the transcriptome of cephalothoraxes among three pigmentation phenotypes (red, blue, and chocolate) of N. denticulate sinensis. The purpose of this study was to explore the candidate genes associated with different colors of N. denticulate sinensis. Nine cDNA libraries in three groups were constructed from the cephalothoraxes of shrimps. After assembly, 75022 unigenes were obtained in total with an average length of 1026 bp and N50 length of 1876 bp. There were 45977, 25284, 23605, 21913 unigenes annotated in the Nr, Swissprot, KOG, and KEGG databases, respectively. Differential expression analysis revealed that there were 829, 554, and 3194 differentially expressed genes (DEGs) in RD vs BL, RD vs CH, and BL vs CH, respectively. These DEGs may play roles in the absorption, transport, and metabolism of carotenoids. We also emphasized that electron transfer across the inner mitochondrial membrane (IMM) was a key process in pigment metabolism. In addition, a total of 6328 simple sequence repeats (SSRs) were also detected in N. denticulate sinensis. The results laid a solid foundation for further research on the molecular mechanism of integument pigmentation in the crustacean and contributed to developing more attractive aquatic animals.


Assuntos
Proteínas de Artrópodes/genética , Carotenoides/metabolismo , Decápodes/genética , Pigmentação/genética , Transcriptoma , Animais , Organismos Aquáticos , Proteínas de Artrópodes/classificação , Proteínas de Artrópodes/metabolismo , Transporte Biológico , Cor , Bases de Dados Genéticas , Decápodes/anatomia & histologia , Decápodes/metabolismo , Água Doce , Regulação da Expressão Gênica , Biblioteca Gênica , Ontologia Genética , Repetições de Microssatélites , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Anotação de Sequência Molecular , Característica Quantitativa Herdável
3.
BMC Plant Biol ; 21(1): 475, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663216

RESUMO

BACKGROUND: Carrot (Daucus carota L.), an important root vegetable, is very popular among consumers as its taproot is rich in various nutrients. Abiotic stresses, such as drought, salt, and low temperature, are the main factors that restrict the growth and development of carrots. Non-heme carotene hydroxylase (BCH) is a key regulatory enzyme in the ß-branch of the carotenoid biosynthesis pathway, upstream of the abscisic acid (ABA) synthesis pathway. RESULTS: In this study, we characterized a carrot BCH encoding gene, DcBCH1. The expression of DcBCH1 was induced by drought treatment. The overexpression of DcBCH1 in Arabidopsis thaliana resulted in enhanced tolerance to drought, as demonstrated by higher antioxidant capacity and lower malondialdehyde content after drought treatment. Under drought stress, the endogenous ABA level in transgenic A. thaliana was higher than that in wild-type (WT) plants. Additionally, the contents of lutein and ß-carotene in transgenic A. thaliana were lower than those in WT, whereas the expression levels of most endogenous carotenogenic genes were significantly increased after drought treatment. CONCLUSIONS: DcBCH1 can increase the antioxidant capacity and promote endogenous ABA levels of plants by regulating the synthesis rate of carotenoids, thereby regulating the drought resistance of plants. These results will help to provide potential candidate genes for plant drought tolerance breeding.


Assuntos
Ácido Abscísico/metabolismo , Arabidopsis/genética , Carotenoides/metabolismo , Daucus carota/genética , Oxigenases de Função Mista/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Antioxidantes/metabolismo , Arabidopsis/fisiologia , Daucus carota/fisiologia , Secas , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Oxigenases de Função Mista/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Estresse Fisiológico
4.
BMC Plant Biol ; 21(1): 416, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34507525

RESUMO

BACKGROUND: Leaf color variation is a common trait in plants and widely distributed in many plants. In this study, a leaf color mutation in Camellia japonica (cultivar named as Maguxianzi, M) was used as material, and the mechanism of leaf color variation was revealed by physiological, cytological, transcriptome and microbiome analyses. RESULTS: The yellowing C. japonica (M) exhibits lower pigment content than its parent (cultivar named as Huafurong, H), especially chlorophyll (Chl) and carotenoid, and leaves of M have weaker photosynthesis. Subsequently, the results of transmission electron microscopy(TEM) exhibited that M chloroplast was accompanied by broken thylakoid membrane, degraded thylakoid grana, and filled with many vesicles. Furthermore, comparative transcriptome sequencing identified 3,298 differentially expressed genes (DEGs). KEGG annotation analysis results showed that 69 significantly enriched DEGs were involved in Chl biosynthesis, carotenoid biosynthesis, photosynthesis, and plant-pathogen interaction. On this basis, we sequenced the microbial diversity of the H and M leaves. The sequencing results suggested that the abundance of Didymella in the M leaves was significantly higher than that in the H leaves, which meant that M leaves might be infected by Didymella. CONCLUSIONS: Therefore, we speculated that Didymella infected M leaves while reduced Chl and carotenoid content by damaging chloroplast structures, and altered the intensity of photosynthesis, thereby causing the leaf yellowing phenomenon of C. japonica (M). This research will provide new insights into the leaf color variation mechanism and lay a theoretical foundation for plant breeding and molecular markers.


Assuntos
Camellia/anatomia & histologia , Camellia/genética , Camellia/metabolismo , Cor , Microbiota , Folhas de Planta/anatomia & histologia , Folhas de Planta/metabolismo , Carotenoides/metabolismo , China , Clorofila/metabolismo , Produtos Agrícolas/anatomia & histologia , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Variação Genética , Genótipo , Fenótipo , Transcriptoma
5.
Plant Sci ; 311: 110996, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34482908

RESUMO

Rubus chingii, is widely distributed in many Asian countries and well known for its medicinal and dietary properties. Diversity of fruit color in raspberry has been attributed to the presence of either anthocyanins or carotenoids. In this study, we investigated anthocyanins and carotenoids, and their biosynthesis by LC-MS/MS. Six anthocyanins mainly consisted of flavanol-anthocyanins while five carotenoids mainly consisted of ß-citraurin esters. Flavanol-anthocyanins were produced from an offshoot of the anthocyanin biosynthesis, which started with biosynthesis of flavanols and anthocyanidin by leucoanthocyanidin reductase (LAR)/anthocyanidin reductase (ANR) and anthocyanidin synthase (ANS/LDOX) respectively. ß-citraurin esters were produced from cleavage of zeaxanthin and esterification by organic acid, which was an offshoot of the carotenoid biosynthesis. The offshoot started with biosynthesis of zeaxanthin and ß-citraurin by carotene ß-hydroxylase (CHYB/LUT5) and carotenoid cleavage dioxygenase (CCD) respectively. During fruit ripening, biosynthesis of flavanols and anthocyanins was down-regulated by genes/proteins involved in phenylpropanoid and flavonoid biosynthesis, while biosynthesis of ß-citraurin esters was up-regulated by imbalanced expression of genes/proteins involved in ß,ß-ring and ß, ε-ring hydroxylation. Thus, ß-citraurin esters, instead of anthocyanins imparted reddish color to the ripe fruit. These pigments and their biosynthesis in R. chingii are totally different from what occurs in other raspberry species.


Assuntos
Antocianinas/metabolismo , Carotenoides/metabolismo , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Pigmentação/fisiologia , Rubus/crescimento & desenvolvimento , Rubus/metabolismo , Antocianinas/genética , China , Frutas/anatomia & histologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Pigmentação/genética , Rubus/anatomia & histologia
6.
PLoS One ; 16(9): e0256802, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34506519

RESUMO

Gardenia jasminoides Ellis (G. jasminoides) fruits are used as a resource for obtaining natural colorants and in traditional Chinese herbal medicine. However, G. jasminoides presents a relatively long flowering period and different ripening periods, so there are significant differences in the accumulation of metabolites in fruits of different colors. In addition, the complete metabolic pathways of iridoidsand crocins, which are used as medicinal composition of G. jasminoides, are poorly understood at present. In this research, we comprehensively compared the transcriptome and metabolites profiles of the developmental stages and locations of iridoid and crocin biosynthesis. A large number of differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) were detected in four groups of samples, and clear variation in the pattern of metabolite abundance and gene expression were observed among different fruit colors and parts. Geniposide and gardenoside mainly accumulated in the sarcocarp of green fruit (GFS) and the sarcocarp of red fruit (FS), respectively. Crocin mainly accumulated in the peel and sarcocarp of red fruits. In the iridoid pathway, we hypothesized that there was a transport mechanism from the sarcocarp to the peel of G. jasminoides because of the inconsistent expression of G8O, 10-HGO and IS associated with differences in fruit ripening. UGTs play an important role in the biosynthesis of the active components of G. jasminoides. Combined transcriptome and metabonomics analysis showed a negative correlation between the biosynthesis of geniposide and crocin. The redirection of the metabolic flux and the regulation of key enzymes may be the main reasons for the changes in the biosynthesis of iridoid and crocin in G. jasminoides fruit. Our study expended valuable information for functional genomic library and provided new insights for metabolic engineering of secondary metabolite in G. Jasminoides.


Assuntos
Carotenoides/metabolismo , Frutas , Gardenia , Iridoides/metabolismo , Frutas/genética , Frutas/metabolismo , Gardenia/genética , Gardenia/metabolismo , Metaboloma , Transcriptoma
7.
PLoS One ; 16(9): e0257745, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34570827

RESUMO

In recent years, much effort has been devoted to understanding the response of plants to various light sources, largely due to advances in industry light-emitting diodes (LEDs). In this study, the effect of different light modes on rocket (Eruca sativa. Mill.) photosynthetic performance and other physiological traits was evaluated using an orthogonal design based on a combination between light intensity, quality, and photoperiod factors. Some morphological and biochemical parameters and photosynthetic efficiency of the plants were analyzed. Plants grew in a closed chamber where three light intensities (160, 190, and 220 µmol m-2 s-1) provided by LEDs with a combination of different ratios of red, green, and blue (R:G:B- 7:0:3, 3:0:7, and 5:2:3) and three different photoperiods (light/dark -10/14 h, 12/12 h, and 14/10 h) were used and compared with white fluorescent light (control). This experimental setup allowed us to study the effect of 9 light modes (LM) compared to white light. The analyzes performed showed that the highest levels of chlorophyll a, chlorophyll b, and carotenoids occurred under LM4, LM3, and LM1, respectively. Chlorophyll a fluorescence measurement showed that the best effective quantum yield of PSII photochemistry Y(II), non-photochemical quenching (NPQ), photochemical quenching coefficient (qP), and electron transport ratio (ETR) were obtained under LM2. The data showed that the application of R7:G0:B3 light mode with a shorter photoperiod than 14/10 h (light/dark), regardless of the light intensity used, resulted in a significant increase in growth as well as higher photosynthetic capacity of rocket plants. Since, a clear correlation between the studied traits under the applied light modes was not found, more features should be studied in future experiments.


Assuntos
Brassicaceae/fisiologia , Fotossíntese , Brassicaceae/crescimento & desenvolvimento , Carotenoides/metabolismo , Clorofila/metabolismo , Luz , Fotoperíodo
8.
BMC Vet Res ; 17(1): 314, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34563199

RESUMO

BACKGROUND: Production, marketability and consumer preference of red tilapia often depends upon the intensity of coloration. Hence, new approaches to develop coloration are now geared to improve market acceptability and profit. This study evaluated the effects of carotenoid-rich diets on the phenotypic coloration, carotenoid level, weight gain and expression of coloration-linked genes in skin, fin and muscle tissues. Carotenoids were extracted from dried Daucus carota peel, Ipomoea aquatica leaves, and Moringa oleifera leaves. Eighty (80) size-14 fish were fed with carotenoid-rich treatments twice a day for 120 days. The phenotypic effect of the carotenoid extracts was measured through a color chart. Skin carotenoid level was measured through UV-vis spectrophotometer. csf1ra, Bcdo2 and StAR expression analysis was done using qRT-PCR. RESULTS: Treatments with carotenoid extracts yielded higher overall scores on phenotypic coloration and tissue carotenoid levels. Differential expression of carotenoid-linked genes such as the elevated expression in csf1ra and lower expression in Bcdo2b following supplementation of the enhanced diet supports the phenotypic redness and increased carotenoid values in red tilapia fed with D. carota peel and I. aquatica leaves. CONCLUSIONS: Overall improvement in the redness of the tilapia was achieved through the supplementation of carotenoid-rich diet derived from readily available plants. Differential expression of coloration-linked genes supports the increase in the intensity of phenotypic coloration and level of carotenoids in the tissues. The study emphasizes the importance of carotenoids in the commercial tilapia industry and highlights the potential of the plant extracts for integration and development of feeds for color enhancement in red tilapia.


Assuntos
Carotenoides/farmacologia , Dieta , Regulação da Expressão Gênica/fisiologia , Pigmentação/genética , Tilápia/genética , Animais , Carotenoides/metabolismo , Pesqueiros
9.
Nutrients ; 13(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34579116

RESUMO

Lutein is a dietary carotenoid preferentially accumulated in the eye and the brain in early life and throughout the life span. Lutein accumulation in areas of high metabolism and oxidative stress such as the eye and the brain suggest a unique role of this ingredient during the development and maturation of these organs of common embryological origin. Lutein is naturally provided to the developing baby via the cord blood, breast milk and then infant diet. The presence of this carotenoid depends on fruit and vegetable intakes and its bioavailability is higher in breastmilk. This paper aims to review the anatomical development of the eye and the brain, explore the presence and selective deposition of lutein in these organs during pregnancy and infancy and, based on its functional characteristics, present the latest available research on the beneficial role of lutein in the pediatric population. The potential effects of lutein in ameliorating conditions associated with increase oxidative stress such as in prematurity will be also addressed. Since consumption of lutein rich foods falls short of government guidelines and in most region of the world infant formulas lack this bioactive, dietary recommendations for pregnant and breastfeeding women and their child can help to bridge the gap.


Assuntos
Encéfalo/crescimento & desenvolvimento , Olho/crescimento & desenvolvimento , Luteína/administração & dosagem , Adolescente , Adulto , Encéfalo/metabolismo , Aleitamento Materno/métodos , Carotenoides/administração & dosagem , Carotenoides/metabolismo , Criança , Pré-Escolar , Dieta/métodos , Olho/metabolismo , Feminino , Frutas/química , Humanos , Lactente , Fórmulas Infantis/química , Luteína/metabolismo , Masculino , Leite Humano/química , Estresse Oxidativo , Gravidez , Xantofilas/metabolismo , Adulto Jovem , Zeaxantinas/metabolismo
10.
Biochem J ; 478(20): 3775-3790, 2021 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-34590677

RESUMO

Reaction centre light-harvesting 1 (RC-LH1) complexes are the essential components of bacterial photosynthesis. The membrane-intrinsic LH1 complex absorbs light and the energy migrates to an enclosed RC where a succession of electron and proton transfers conserves the energy as a quinol, which is exported to the cytochrome bc1 complex. In some RC-LH1 variants quinols can diffuse through small pores in a fully circular, 16-subunit LH1 ring, while in others missing LH1 subunits create a gap for quinol export. We used cryogenic electron microscopy to obtain a 2.5 Šresolution structure of one such RC-LH1, a monomeric complex from Rhodobacter sphaeroides. The structure shows that the RC is partly enclosed by a 14-subunit LH1 ring in which each αß heterodimer binds two bacteriochlorophylls and, unusually for currently reported complexes, two carotenoids rather than one. Although the extra carotenoids confer an advantage in terms of photoprotection and light harvesting, they could impede passage of quinones through small, transient pores in the LH1 ring, necessitating a mechanism to create a dedicated quinone channel. The structure shows that two transmembrane proteins play a part in stabilising an open ring structure; one of these components, the PufX polypeptide, is augmented by a hitherto undescribed protein subunit we designate as protein-Y, which lies against the transmembrane regions of the thirteenth and fourteenth LH1α polypeptides. Protein-Y prevents LH1 subunits 11-14 adjacent to the RC QB site from bending inwards towards the RC and, with PufX preventing complete encirclement of the RC, this pair of polypeptides ensures unhindered quinone diffusion.


Assuntos
Proteínas de Bactérias/química , Complexos de Proteínas Captadores de Luz/química , Peptídeos/química , Fotossíntese/fisiologia , Complexo de Proteínas do Centro de Reação Fotossintética/química , Rhodobacter sphaeroides/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacterioclorofilas/química , Bacterioclorofilas/metabolismo , Sítios de Ligação , Carotenoides/química , Carotenoides/metabolismo , Microscopia Crioeletrônica , Expressão Gênica , Hidroquinonas/química , Hidroquinonas/metabolismo , Luz , Complexos de Proteínas Captadores de Luz/genética , Complexos de Proteínas Captadores de Luz/metabolismo , Modelos Moleculares , Peptídeos/genética , Peptídeos/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/metabolismo , Rhodobacter sphaeroides/efeitos da radiação
11.
Metab Eng ; 68: 86-93, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34555495

RESUMO

Coenzyme Q (CoQ) is vital for energy metabolism in living organisms. In humans, CoQ10 deficiency causes diseases and must be replenished via diet; however, CoQ content in plant foods is primarily low. Here, we report the breeding of high CoQ10 tomato lines by expressing four enzymes with a fruit-specific promoter, which modifies the chloroplast chorismate pathway, enhances cytosolic isoprenoid biosynthesis, and up-regulates the first two reactions in mitochondrion that construct the CoQ10 polyisoprenoid tail. We show that, while the level of the aromatic precursor could be markedly elevated, head group prenylation is the key to increasing the final CoQ10 yield. In the HUCD lines expressing all four transgenes, the highest CoQ10 content (0.15 mg/g dry weight) shows a seven-fold increase from the wild-type level and reaches an extraordinarily rich CoQ10 food grade. Overviewing the changes in other terpenoids by transcriptome and metabolic analyses reveals variable contents of carotenoids and α-tocopherol in the HUCD lines. In addition to the enigmatic relations among different terpenoid pathways, high CoQ10 plants maintaining substantial levels of either vitamin can be selected. Our investigation paves the way for the development of CoQ10-enriched crops as dietary supplements.


Assuntos
Lycopersicon esculentum , Ubiquinona , Carotenoides/metabolismo , Frutas/metabolismo , Humanos , Lycopersicon esculentum/genética , Mitocôndrias , Ubiquinona/genética
12.
Environ Toxicol Pharmacol ; 88: 103746, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34536620

RESUMO

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a popular group of drugs used worldwide. These drugs are also available over the counter, which implies that their consumption is not strictly regulated. They are released through wastewater and feces and can have adverse effects on the environment. The present study aimed to evaluate the effect of two NSAIDs, diclofenac (DCF) and naproxen (NAP), and their mixture (DCF + NAP) on spring barley seedlings and ostracods Heterocypris incongruens. The tested drugs had a negative impact on bivalve ostracods and the studied plants. DCF was the most toxic toward ostracods, while spring barley seedlings were affected the most by NAP. The application of the tested compounds and their mixture resulted in a decrease in fresh weight yield and the content of photosynthetic pigments. In addition, an increase in H2O2 and proline content and changes in the activity of antioxidant enzymes (POD, APX, CAT, and SOD) were observed.


Assuntos
Anti-Inflamatórios não Esteroides/toxicidade , Crustáceos/efeitos dos fármacos , Diclofenaco/toxicidade , Hordeum/efeitos dos fármacos , Naproxeno/toxicidade , Plântula/efeitos dos fármacos , Animais , Carotenoides/metabolismo , Clorofila/metabolismo , Crustáceos/crescimento & desenvolvimento , Interações Medicamentosas , Hordeum/crescimento & desenvolvimento , Hordeum/metabolismo , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismo , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Prolina/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
13.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445145

RESUMO

The main goal of growing plants under various photoperiods is to optimize photosynthesis for using the effect of day length that often acts on plants in combination with biotic and/or abiotic stresses. In this study, Brassica juncea plants were grown under four different day-length regimes, namely., 8 h day/16 h night, 12 h day/12 h night, 16 h day/8 h night, and continuous light, and were infected with a necrotrophic fungus Alternaria brassicicola. The development of necroses on B. juncea leaves was strongly influenced by leaf position and day length. The largest necroses were formed on plants grown under a 16 h day/8 h night photoperiod at 72 h post-inoculation (hpi). The implemented day-length regimes had a great impact on leaf morphology in response to A. brassicicola infection. They also influenced the chlorophyll and carotenoid contents and photosynthesis efficiency. Both the 1st (the oldest) and 3rd infected leaves showed significantly higher minimal fluorescence (F0) compared to the control leaves. Significantly lower values of other investigated chlorophyll a fluorescence parameters, e.g., maximum quantum yield of photosystem II (Fv/Fm) and non-photochemical quenching (NPQ), were observed in both infected leaves compared to the control, especially at 72 hpi. The oldest infected leaf, of approximately 30% of the B. juncea plants, grown under long-day and continuous light conditions showed a 'green island' phenotype in the form of a green ring surrounding an area of necrosis at 48 hpi. This phenomenon was also reflected in changes in the chloroplast's ultrastructure and accelerated senescence (yellowing) in the form of expanding chlorosis. Further research should investigate the mechanism and physiological aspects of 'green islands' formation in this pathosystem.


Assuntos
Alternaria/patogenicidade , Mostardeira/microbiologia , Mostardeira/fisiologia , Necrose/microbiologia , Necrose/patologia , Fotossíntese/fisiologia , Doenças das Plantas/microbiologia , Carotenoides/metabolismo , Clorofila/metabolismo , Clorofila A/metabolismo , Fluorescência , Mostardeira/metabolismo , Necrose/metabolismo , Fotoperíodo , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia
14.
Nat Commun ; 12(1): 4929, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389727

RESUMO

Synthetic metabolic pathways are a burden for engineered bacteria, but the underlying mechanisms often remain elusive. Here we show that the misregulated activity of the transcription factor Cra is responsible for the growth burden of glycerol overproducing E. coli. Glycerol production decreases the concentration of fructose-1,6-bisphoshate (FBP), which then activates Cra resulting in the downregulation of glycolytic enzymes and upregulation of gluconeogenesis enzymes. Because cells grow on glucose, the improper activation of gluconeogenesis and the concomitant inhibition of glycolysis likely impairs growth at higher induction of the glycerol pathway. We solve this misregulation by engineering a Cra-binding site in the promoter controlling the expression of the rate limiting enzyme of the glycerol pathway to maintain FBP levels sufficiently high. We show the broad applicability of this approach by engineering Cra-dependent regulation into a set of constitutive and inducible promoters, and use one of them to overproduce carotenoids in E. coli.


Assuntos
Escherichia coli/genética , Glicólise/genética , Engenharia Metabólica/métodos , Metabolômica/métodos , Proteômica/métodos , Transcrição Genética , Algoritmos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Sítios de Ligação/genética , Carotenoides/metabolismo , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Modelos Genéticos , Regiões Promotoras Genéticas/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
15.
Plant Physiol Biochem ; 167: 91-100, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34340026

RESUMO

The relationship between photosynthesis, pigment accumulation, and the expression of key light-regulated genes in Solanum lycopersicum hp-1, hp-2 and hp-1.2 photomorphogenetic mutants under conditions of high-intensity light (2000 µm (photons) m-2s-1) was studied. The hp-2 mutant (LA3006) and the hp-1 mutants (LA4012 and LA3538) are deficient in DET1 (De-etiolated 1 and DDB1 (DNA DAMAGE-BINDING PROTEIN 1), respectively, which are components of the CDD complex (COP10, DDB1, DET1). HP mutants are superproducers of various pigments and are sensitive to light. We have shown that HIL (high-intensity light) causes a decrease in PSII activity after 24 and 72 h of irradiation, which was partially restored after 72 h in the WT. The photosynthetic rate noticeably decreased only in LA4012 and LA3538 after 24 h of irradiation. After 72 h, the photosynthetic rate decreased in all mutants, with the exception of hp-1.2 LA0279, but the decrease was most noticeable in LA4012, yet significant changes in the respiration rate were absent. The LA0279 mutant was more capable of accumulating anthocyanin in the cells of the subepidermal parenchyma and chlorenchyma, as well as in the cells at the base of large multicellular glandular trichomes and in the mesophyll. Another important difference was the accumulation of increased amounts of antheraxanthin and phenolic compounds in the leaves of LA0279 after 72 h of HIL irradiation. Unlike LA4012, LA3006, LA0279, and LA3538 sowed a significant increase in the expression levels of CHS, HY5, and FLS genes after 24 h, which may be one of the reasons for the higher adaptive potential of those three mutants. In addition to that in LA3538, strong light-induced stress led to an increased level of flavonol synthase (FLS) expression in the LA3006, LA0279, and LA4012 mutants. We hypothesize that the photosynthetic apparatus (PA) of the LA0279 mutant, which is deficient in the DET1 and DDB1 genes, is most adapted to prolonged HIL. Most likely, the resistance of PA mutants to HIL is due to a variety of factors, which, in addition to the redistribution of carotenoids, may include morphological features associated with the accumulation of anthocyanin in the epidermis, subepidermal layer, mesophyll and trichomes of leaves and with an increase in leaf thickness.


Assuntos
Lycopersicon esculentum , Carotenoides/metabolismo , Lycopersicon esculentum/genética , Lycopersicon esculentum/metabolismo , Fotossíntese/genética , Pigmentação , Folhas de Planta/metabolismo
16.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445522

RESUMO

Crocetin is an apocarotenoid formed from the oxidative cleavage of zeaxanthin, by the carotenoid cleavage enzymes CCD2 (in Crocus species) and specific CCD4 enzymes in Buddleja davidii and Gardenia jasminoides. Crocetin accumulates in the stigma of saffron in the form of glucosides and crocins, which contain one to five glucose molecules. Crocetin glycosylation was hypothesized to involve at least two enzymes from superfamily 1 UDP-sugar dependent glycosyltransferases. One of them, UGT74AD1, produces crocins with one and two glucose molecules, which are substrates for a second UGT, which could belong to the UGT79, 91, or 94 families. An in silico search of Crocus transcriptomes revealed six candidate UGT genes from family 91. The transcript profiles of one of them, UGT91P3, matched the metabolite profile of crocin accumulation, and were co-expressed with UGT74AD1. In addition, both UGTs interact in a two-hybrid assay. Recombinant UGT91P3 produced mostly crocins with four and five glucose molecules in vitro, and in a combined transient expression assay with CCD2 and UGT74AD1 enzymes in Nicotiana benthamiana. These results suggest a role of UGT91P3 in the biosynthesis of highly glucosylated crocins in saffron, and that it represents the last missing gene in crocins biosynthesis.


Assuntos
Carotenoides/metabolismo , Crocus/enzimologia , Perfilação da Expressão Gênica/métodos , Glicosiltransferases/genética , Vias Biossintéticas , Simulação por Computador , Crocus/química , Crocus/genética , Regulação da Expressão Gênica de Plantas , Glicosilação , Proteínas de Plantas/genética , Técnicas do Sistema de Duplo-Híbrido
17.
Int J Mol Sci ; 22(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34445525

RESUMO

Carotenoids are natural lipophilic pigments mainly found in plants, but also found in some animals and can be synthesized by fungi, some bacteria, algae, and aphids. These pigments are used in food industries as natural replacements for artificial colors. Carotenoids are also known for their benefits to human health as antioxidants and some compounds have provitamin A activity. The production of carotenoids by biotechnological approaches might exceed yields obtained by extraction from plants or chemical synthesis. Many microorganisms are carotenoid producers; however, not all are industrially feasible. Therefore, in this review, we provide an overview regarding fungi that are potentially interesting to industry because of their capacity to produce carotenoids in response to stresses on the cultivation medium, focusing on low-cost substrates.


Assuntos
Antioxidantes/metabolismo , Biotecnologia/métodos , Carotenoides/metabolismo , Engenharia Genética , Animais , Humanos , Especificidade por Substrato
18.
Plant Mol Biol ; 107(1-2): 49-62, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34417937

RESUMO

KEY MESSAGE: Two MYB genes have been identified which regulate apocarotenoid metabolism in Crocus sativus. Apocarotenoids like crocin, picrocrocin and safranal are restricted to genus Crocus and are synthesized by oxidative cleavage of zeaxanthin followed by glycosylation reactions. In Crocus sativus, these apocarotenoids are synthesized in stigma part of the flower in developmentally regulated manner. Most of the genes of apocarotenoid pathway are known, however, the mechanism that regulates its tissue and stage specific biosynthesis remains elusive. MYB family was identified as the largest transcription factor family from Crocus transciptome which indicated its possible role in apocarotenoid regulation besides regulating other metabolic pathways. Towards this, we started with identification of 150 MYB genes from Crocus transcriptome databases. The phylogenetic analysis of Crocus MYB genes divided them into 27 clusters. Domain analysis resulted in identification of four groups of MYBs depending upon the number of R repeats present. Expression profiling indicated that 12 MYBs are upregulated in stigma out of which expression of four genes CstMYB1, CstMYB14, CstMYB16 and CstMYB1R2 correlated with crocin accumulation. Transient overexpression of two nuclear localized MYB genes (CstMYB1 and CstMYB1R2) in Crocus confirmed their role in regulating carotenoid metabolism. Yeast-one-hybrid confirmed that CstMYB1 binds to carotenoid cleavage dioxygenase 2 (CCD2) promoter while CstMYB1R2 binds to phytoene synthase (PSY) and CCD2 promoters. Overall, our study established that CstMYB1 and CstMYB1R2 regulate apocarotenoid biosynthesis by directly binding to promoters of pathway genes.


Assuntos
Carotenoides/metabolismo , Crocus/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Plantas/genética , Fatores de Transcrição/genética , Sequência de Bases , Núcleo Celular/metabolismo , Perfilação da Expressão Gênica , Filogenia , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Genética , Transcriptoma
19.
Bioresour Technol ; 341: 125782, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34419880

RESUMO

The carotenoid, α-carotene, is very beneficial for human health and wellness, but microbial production of this compound is notoriously difficult, due to the asymmetric rings on either end of its terpenoid backbone. Here, we report for the first time the efficient production of α-carotene in the industrial bacterium Corynebaterium glutamicum by using a combined pathway engineering approach including evaluation of the performance of different cyclases and analysis of key metabolic intermediates to determine flux bottlenecks in the carotenoid biosynthesis pathway. A multi-copy chromosomal integration method was pivotal in achieving stable expression of the cyclases. In fed-batch fermentation, 1,054 mg/L of α-carotene was produced by the best strain, which is the highest reported titer achieved in microbial fermentation. The success of increased α-carotene production suggests that the multi-copy chromosomal integration method can be a useful metabolic engineering tool for overexpression of key enzymes in C. glutamicum and other bacterium as well.


Assuntos
Corynebacterium glutamicum , Carotenoides/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Fermentação , Humanos , Engenharia Metabólica
20.
Molecules ; 26(16)2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34443643

RESUMO

Pomelo is rich in bioactive compounds (carotenoids, phenolics and essential oil) in the early stage of fruit development, but it is often wasted in the cultivation and management process. To gain an insight into the carotenoid metabolism pathway in pomelo, the carotenoid profiles and the expression patterns of carotenogenic genes were investigated in two genotypes of pomelo during early fruit development. The results showed that a higher carotenoid content was observed in honey pomelo as compared with golden pomelo, which may be related to different gene regulation mechanisms. Lutein, α-carotene, and ß-carotene were the main carotenoids in pomelo young fruit, and lutein was the highest one. The accumulation of carotenoids during fruit early development in honey pomelo is related to the transcriptional regulation of ZISO and LUT5. In golden pomelo, the rate-limiting gene for carotenoids is PDS and ZDS. In addition, the expression of seven genes except CRTISO in honey pomelo was higher than that in golden pomelo. The results are helpful to further clarify the regulatory mechanism of carotenoid accumulation during early fruit development and provide a direction for the high-value utilization of young fruits in pomelo.


Assuntos
Carotenoides/metabolismo , Citrus/genética , Citrus/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Genótipo , Luteína/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
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