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1.
J Agric Food Chem ; 68(1): 59-66, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31816240

RESUMO

Exposure of mature green "Takanotsume" chili fruit to blue and red light-emitting diodes (LEDs) was investigated. The red LED accelerated the red color development of chili as indicated by higher a* and chroma values, as well as lower hue angle and total chlorophyll compared to the blue LED and darkness (control). These were linked to increases in ß-carotene, free-capsanthin, and total carotenoids. The carotenoid biosynthesis-related genes, lycopene-ß-cyclase (Lcyb), ß-carotene hydroxylase (CrtZ), and capsanthin/capsolubin synthase (Ccs), were up-regulated by the red LED after 2 days of the experiment. The blue LED was more effective in increasing the expression of the phytoene synthase (Psy) gene at day 1 of experiment. The total phenolic, vitamin C content, and antioxidant capacity were also higher in the blue LED-treated chili. Results suggest that the responses of each carotenoid-related gene to the light wavelengths and the accumulation of phytochemicals are specific characteristics of this chili cultivar.


Assuntos
Capsicum/metabolismo , Capsicum/efeitos da radiação , Compostos Fitoquímicos/metabolismo , Pigmentos Biológicos/metabolismo , Capsicum/crescimento & desenvolvimento , Carotenoides/metabolismo , Cor , Frutas/química , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Luz , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Xantofilas/metabolismo , beta Caroteno/metabolismo
2.
J Agric Food Chem ; 68(3): 808-817, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31870144

RESUMO

Various Monascus bioactive metabolites used as food or food additives in Asia for centuries are subjected to constant physical and chemical changes and different Monascus genus. With the aim to identify enzymes that participate in or indirectly regulate the pigments and citrinin biosynthesis pathways of Monascus purpureus cultured under high ammonium chloride, the changes of the proteome profile were examined using sequential window acquisition of all theoretical mass spectra-mass spectrometry-based quantitative proteomics approach in combination with bioinformatics analysis. A total of 292 proteins were confidently detected and quantified in each sample, including 163 that increased and 129 that decreased (t-tests, p ≤ 0.05). Pathway analysis indicated that high ammonium chloride in the present study accelerates the carbon substrate utilization and promotes the activity of key enzymes in glycolysis and ß-oxidation of fatty acid catabolism to generate sufficient acetyl-CoA. However, the synthesis of the monascus pigments and citrinin was not enhanced because of inhibition of the polyketide synthase activity. All results demonstrated that the cause of initiation of pigments and citrinin synthesis is mainly due to the apparent inhibition of acyl and acetyl transfer by some acyltransferase and acetyltransferase, likely malony-CoA:ACP transacylase.


Assuntos
Cloreto de Amônio/metabolismo , Citrinina/biossíntese , Monascus/metabolismo , Pigmentos Biológicos/metabolismo , Acetiltransferases/metabolismo , Aciltransferases/metabolismo , Citrinina/química , Proteínas Fúngicas/metabolismo , Espectrometria de Massas , Monascus/química , Pigmentos Biológicos/química , Proteômica
3.
J Microbiol ; 57(12): 1079-1085, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31758394

RESUMO

A yellow pigmented, Gram-stain-negative, strictly aerobic, rod-shaped, motile by means of gliding, catalase and oxidase positive bacterium, designated strain DS2-AT, was isolated from soil. Growth was observed at 4-32°C (optimum, 28°C), pH 6-9 (optimum, 7.0), and with 0-0.25% (w/v) NaCl (optimum, 0%). Phylogenetic analysis of 16S rRNA gene sequence revealed that strain DS2-AT belonged to the genus Flavobacterium and was most closely related to Flavobacterium aquatile LMG 4008T (96.4%), Flavobacterium terrae DSM 18829T (95.6%), Flavobacterium vireti THG-SM1T (95.5%), Flavobacterium inkyongense IMCC27201T (95.4%), Flavobacterium brevivitae TTM-43T (95.2%), and Flavobacterium cucumis DSM 18830T (95.2%). Strain DS2-AT produces flexirubin-type pigments. The major fatty acids were iso-C15:0, iso-C17:0 3-OH, and iso-C15:0 3-OH. The major respiratory quinone was identified as menaquinone-6. The major polar lipid was found to be phosphatidylethanolamine. The average nucleotide identity values between strain DS2-AT and selected taxa, F. aquatile LMG 4008T, F. terrae DSM 18829T, and F. cucumis DSM 18830T, were 72, 72.7, and 71.6%, respectively. The draft genome of strain DS2-AT has a number of 14 contigs, scaffold N50 of 476,310 bp and a total size of 3,563,867 bp. Additionally, strain DS2-AT contains 3,127 of gene, 41 of tRNA, 6 of rRNA, and 3 of ncRNA. The DNA G + C content of stain DS2-AT was 40.7 mol%. Based on phylogenetic and phenotypic analyses, strain DS2-AT is considered as a novel species of the genus Flavobacterium, for which the name Flavobacterium humi sp. nov., (type strain DS2-AT = KACC 19715T = JCM 32786T) has been proposed.


Assuntos
Flavobacterium/classificação , Flavobacterium/isolamento & purificação , Flavobacterium/metabolismo , Filogenia , Pigmentos Biológicos/metabolismo , Polienos/metabolismo , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/análise , Flavobacterium/genética , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/análise , RNA Ribossômico 16S/genética , República da Coreia , Análise de Sequência de DNA , Solo , Vitamina K 2/análogos & derivados , Vitamina K 2/análise
4.
J Basic Microbiol ; 59(12): 1208-1216, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613006

RESUMO

The current research focuses on anaerobic respiration of arsenic and other toxic metals by purple nonsulfur bacteria (PNSB). Among the optimization assays performed were carbon utilization, cross metal resistance, and metal respiration, along with a comparison of each assay in photoheterotrophic and chemoheterotrophic growth. The bacteria were identified by the classification of 16S ribosomal RNA gene sequences. Rhodobacter sp. PI3 proved to be more versatile in carbon source utilization (acetate, lactate, citrate, and oxalate), whereas Rhodopseudomonas palustris PI5 proved to be more versatile in metal resistance (arsenate, arsenite, cobalt, lead, selenium, and nickel). Both the strains were found to be positive for photofermentative hydrogen production along with arsenic respiration. This study reveals that anaerobic conditions are more appropriate for better efficiency of PNSB. Our study demonstrates that R. palustris PI5 and Rhodobacter sp. PI3 can be promising candidates for the biohydrogen production along with metal detoxification using heavy metal-polluted effluents as a substrate.


Assuntos
Arsênico/metabolismo , Hidrogênio/metabolismo , Metais/metabolismo , Rhodobacter/metabolismo , Rodopseudomonas/metabolismo , Anaerobiose , Biodegradação Ambiental , Carbono/metabolismo , DNA Bacteriano/genética , Processos Heterotróficos , Filogenia , Pigmentos Biológicos/metabolismo , RNA Ribossômico 16S/genética , Rhodobacter/classificação , Rhodobacter/genética , Rodopseudomonas/classificação , Rodopseudomonas/genética , Análise de Sequência de DNA , Microbiologia da Água
5.
World J Microbiol Biotechnol ; 35(11): 166, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31641867

RESUMO

Microbial secondary metabolites (SMs) have been identified as an important natural source of drugs for several metabolic and neurological diseases. Along with biomedical applications, SMs are also used in the food and biochemical industries. SMs include natural products such as pigments, alkaloids, toxins, antimicrobials obtained from cultured microorganisms, while other non-cultivable microorganisms have also acted as a rich source of SMs. But, the isolation of SMs from these sources is a very tedious task. Metabolomics provides complete identification and structural information about the entire cellular metabolome under specific conditions using highly sophisticated instrumentation. Further, gene editing techniques such as cloning and gene refactoring, including advanced CRISPR-Cas, can be used for engineering microbes that have the potential to produce natural SMs that were not produced in native microbial strain. The present review describes integrated metabolomics and gene editing approaches for the synthesis of novel microbial SMs and their potential application towards drug discovery and development.


Assuntos
Desenvolvimento de Medicamentos/métodos , Descoberta de Drogas/métodos , Edição de Genes/métodos , Metabolômica/métodos , Fenômenos Microbiológicos , Metabolismo Secundário , Alcaloides/metabolismo , Antimitóticos/metabolismo , Produtos Biológicos , Sistemas CRISPR-Cas , Bases de Dados Factuais , Deleção de Genes , Engenharia Genética/métodos , Análise Multivariada , Mutagênese Insercional , Pigmentos Biológicos/metabolismo , Toxinas Biológicas/metabolismo
6.
World J Microbiol Biotechnol ; 35(10): 160, 2019 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606850

RESUMO

In this work Talaromyces australis and Penicillium murcianum pigment production in liquid cultures and the cytotoxic effect of such pigments on skin model cells were studied. Response surface methodology (RSM) was used to optimize culture conditions aiming to increase pigment production in malt extract and peptone-glucose-yeast extract medium. Cytotoxicity of fungal pigments and also from lixiviates of wool fabrics dyed with T. australis and P. murcianum pigment was evaluated on mammalian cell lines HEK293 and NIH/3T3. Results showed that variations on initial pH, NaCl and peptone, resulted in increments up to 188.2% for red pigment of T. australis and 107.4% for yellow pigment of P. murcianum, regarding non-optimized conditions. Tested fungi also showed great differences in culture conditions for the maximum pigment production, with P. murcianum requiring an alkaline medium (initial pH 9) supplemented with NaCl and T. australis an acidic medium (initial pH 5) without addition of salt. The cytotoxicity assays provided evidences on the safe nature of these natural pigments when used for textile applications. The cytotoxicity assay showed that the threshold of toxicity, given by the lowest IC50 value (0.21 g L-1) was more than double of the concentration of pigment required to dye the wool samples. In addition, cytotoxicity of lixiviates depicted no toxic effect over tested cells.


Assuntos
Meios de Cultura/química , Penicillium/metabolismo , Pigmentos Biológicos/metabolismo , Talaromyces/metabolismo , Têxteis/microbiologia , Animais , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Células NIH 3T3 , Cloreto de Sódio/metabolismo
7.
BMC Plant Biol ; 19(1): 390, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31500571

RESUMO

BACKGROUND: The primary pigments in flowers are anthocyanins, the biosynthesis of which is mainly regulated by R2R3-MYBs. Muscari armeniacum is an ornamental garden plant with deep cobalt blue flowers containing delphinidin-based anthocyanins. An anthocyanin-related R2R3-MYB MaAN2 has previously been identified in M. armeniacum flowers; here, we also characterized a novel R2R3-MYB MaMybA, to determine its function and highlight similarities and differences between MaMybA and MaAN2. RESULTS: In this study, a novel anthocyanin-related R2R3-MYB gene was isolated from M. armeniacum flowers and functionally identified. A sequence alignment showed that MaMybA contained motifs typically conserved with MaAN2 and its orthologs. However, the shared identity of the entire amino acid sequence between MaMybA and MaAN2 was 43.5%. Phylogenetic analysis showed that they were both clustered into the AN2 subgroup of the R2R3-MYB family, but not in the same branch. We also identified a IIIf bHLH protein, MabHLH1, in M. armeniacum flowers. A bimolecular fluorescence complementation assay showed that MabHLH1 interacted with MaMybA or MaAN2 in vivo; a dual luciferase assay indicated that MaMybA alone or in interaction with MabHLH1 could regulate the expression of MaDFR and AtDFR, but MaAN2 required MabHLH1 to do so. When overexpressing MaMybA in Nicotiana tabacum 'NC89', the leaves, petals, anthers, and calyx of transgenic tobacco showed intense and magenta anthocyanin pigments, whereas those of OE-MaAN2 plants had lighter pigmentation. However, the ovary wall and seed skin of OE-MaMybA tobacco were barely pigmented, while those of OE-MaAN2 tobacco were reddish-purple. Moreover, overexpressing MaMybA in tobacco obviously improved anthocyanin pigmentation, compared to the OE-MaAN2 and control plants, by largely upregulating anthocyanin biosynthetic and endogenous bHLH genes. Notably, the increased transcription of NtF3'5'H in OE-MaMybA tobacco might lead to additional accumulation of delphinidin 3-rutinoside, which was barely detected in OE-MaAN2 and control plants. We concluded that the high concentration of anthocyanin and the newly produced Dp3R caused the darker color of OE-MaMybA compared to OE-MaAN2 tobacco. CONCLUSION: The newly identified R2R3-MYB transcription factor MaMybA functions in anthocyanin biosynthesis, but has some differences from MaAN2; MaMybA could also be useful in modifying flower color in ornamental plants.


Assuntos
Antocianinas/metabolismo , Asparagaceae/fisiologia , Regulação da Expressão Gênica de Plantas , Pigmentos Biológicos/genética , Proteínas de Plantas/genética , Tabaco/fisiologia , Fatores de Transcrição/genética , Sequência de Aminoácidos , Asparagaceae/genética , Asparagaceae/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Cor , Flores/genética , Flores/fisiologia , Filogenia , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Alinhamento de Sequência , Tabaco/genética , Tabaco/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
8.
Nat Commun ; 10(1): 3579, 2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31395863

RESUMO

It is thought that fungi protect themselves from predation by the production of compounds that are toxic to soil-dwelling animals. Here, we show that a nontoxic pigment, the bis-naphthopyrone aurofusarin, protects Fusarium fungi from a wide range of animal predators. We find that springtails (primitive hexapods), woodlice (crustaceans), and mealworms (insects) prefer feeding on fungi with disrupted aurofusarin synthesis, and mealworms and springtails are repelled by wheat flour amended with the fungal bis-naphthopyrones aurofusarin, viomellein, or xanthomegnin. Predation stimulates aurofusarin synthesis in several Fusarium species and viomellein synthesis in Aspergillus ochraceus. Aurofusarin displays low toxicity in mealworms, springtails, isopods, Drosophila, and insect cells, contradicting the common view that fungal defence metabolites are toxic. Our results indicate that bis-naphthopyrones are defence compounds that protect filamentous ascomycetes from predators through a mechanism that does not involve toxicity.


Assuntos
Artrópodes/efeitos dos fármacos , Aspergillus ochraceus/fisiologia , Fusarium/fisiologia , Naftoquinonas/farmacologia , Pigmentos Biológicos/farmacologia , Adaptação Fisiológica , Animais , Artrópodes/fisiologia , Preferências Alimentares/efeitos dos fármacos , Naftoquinonas/metabolismo , Pigmentos Biológicos/metabolismo , Comportamento Predatório/efeitos dos fármacos
9.
Aquat Toxicol ; 215: 105271, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31470337

RESUMO

Microcystis blooms and their associated microcystins pose a significant health risk to humans. Microcystis normally occurs as colonies in eutrophic water bodies, and its physiological tolerance to algaecides is dissimilar to that of unicellular forms. However, the differences of physiological response to algaecides between unicellular and colonial Microcystis have been poorly explored. The current study investigated the effects of hexane extract of Acorus calamus rhizome (HEACR) on the physiological and photosynthetic mechanisms of unicellular and colonial M. aeruginosa in the laboratory. We analyzed the cell density, reactive oxygen species (ROS) level, malonaldehyde (MDA) content, photosynthetic pigments, capsular polysaccharide (CPS), and photosystem (PS II) parameters of the two morphological forms of Microcystis. Our results show that HEACR suppresses the growth of both unicellular and colonial M. aeruginosa, increases the intracellular ROS level and cause lipid peroxidation, as well as exerting a detrimental effect on chlorophyll a (chl a) content and photosynthetic efficiency. Almost 100% inhibition was observed for unicellular and colonial M. aeruginosa after 3 d exposure to 50 and 100 mg L-1 HEACR, respectively. The ROS level increase, MDA accumulation, the chl a decrease and carotenoid increase in unicellular M. aeruginosa were all more obvious than that in colonial cells. The fall in photosynthetic efficiency of unicellular M. aeruginosa were also more significant than that of colonial cells. After 3d exposure, the maximum quantum yield of PS II photochemistry (Fv/Fm), effective quantum yield of PS II photochemistry (Fv'/Fm') and effective quantum yield of photochemical energy conversion in PS II (YII) of unicellular M. aeruginosa was almost totally inhibited by 20 mg L-1 HEACR, while the Fv/Fm, Fv'/Fm' and YII of colonial M. aeruginosa decreased by 43%, 26% and 66% for 100 mg L-1 of HEACR, respectively. Comparing the two morphological forms of Microcystis, colonies show a greater increase in CPS level to more effectively resist the stress of HEACR and to mitigate ROS generation thereby better defending against oxidative damage. Furthermore, colonial M. aeruginosa shows better photoprotection ability than the unicellular form when exposed to HEACR. The colonies also sustain their maximum electron transport rate, increase their tolerance to strong light, and maintain a higher ability to disperse excess energy. These results demonstrated that HEACR can significantly interfere with the growth and physiological processes of both unicellular and colonial M. aeruginosa, but that colonial M. aeruginosa has a greater ability to adjust physiological tolerance to resist the stresses of HEACR.


Assuntos
Acorus/química , Microcystis/efeitos dos fármacos , Microcystis/fisiologia , Extratos Vegetais/farmacologia , Rizoma/química , Luz , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Microcystis/crescimento & desenvolvimento , Fotossíntese/efeitos dos fármacos , Fotossíntese/efeitos da radiação , Pigmentos Biológicos/metabolismo , Polissacarídeos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
10.
Food Chem ; 299: 125140, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31299520

RESUMO

Pigment-depletion in the fillets of farmed Atlantic salmon (Salmo salar) arises after periods of elevated water temperatures with voluntary starving. This study tested the effects of dietary pre-loading with different pigment carotenoids (astaxanthin and/or canthaxanthin) combined with two α-tocopherol levels (normal and high: 500 and 1000 mg/kg, respectively) on pigment-depletion in vivo in Atlantic salmon after four weeks of challenge. We also tested whether oxidative stress manifested as an underlying depletion mechanism. Carotenoid levels in whole fillet homogenates were not decreased significantly post-challenge but fillet α-tocopherol concentrations were increased significantly in contrast to decreased oxidative stress indices. However, image analysis revealed localised fillet pigment-depletion following all dietary treatments. These data imply that localised pigment-depletion was not prevented by pre-loading of the fillet with different carotenoid-types/mixtures and increased of α-tocopherol levels from normal to high, respectively. Further, we suggest that oxidative stress might not facilitate pigment-depletion in vivo.


Assuntos
Cantaxantina/metabolismo , Pigmentos Biológicos/metabolismo , Salmo salar/fisiologia , alfa-Tocoferol/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aquicultura/métodos , Cantaxantina/análise , Dieta , Feminino , Produtos Pesqueiros/análise , Estresse Oxidativo , Pigmentação , Inanição , Temperatura Ambiente , Xantofilas/análise , Xantofilas/metabolismo
11.
Bioresour Technol ; 291: 121846, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31362199

RESUMO

The aim of this study was to evaluatethe effects of different colored light emitting diodes (LEDs) on the growth, pigment yield, and photosynthetic performance of Arthrospira maxima, a commercially exploited species of cyanobacteria. The highest growth and chlorophyll a (Chl a) concentration were obtained under red LED and white fluorescent light, while the lowest growth and Chlaconcentration were observed under blue LED. However, blue LED produced the highest levels of phycobiliproteins (3.20 mg·g-1phycocyanin [PC]; 0.19 mg·g-1 allophycocyanin [APC]; 0.97 mg·g-1for phycoerythrin [PE], effective quantum yield (ΦPSII) and maximum relative electron transport rate (rETRmax) inA. maxima. The results of this study suggest that red and blue LEDs increase the biomass yield and pigment content of cyanobacteria, respectively, and the combined use of red and blue light may significantly improve algal biomass and biopigment yield.


Assuntos
Fotossíntese , Spirulina/metabolismo , Biomassa , Clorofila A/metabolismo , Cor , Iluminação/métodos , Pigmentos Biológicos/metabolismo
12.
Antonie Van Leeuwenhoek ; 112(10): 1559-1565, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31172329

RESUMO

A Gram-stain negative, non-motile, and yellow-coloured bacterium, designated 17J28-26T, was isolated from soil in Jeju Island, Korea. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain 17J28-26T formed a distinct lineage within the family Chitinophagaceae (order Chitinophagales, class Chitinophagia), and is closely related to Flavisolibacter ginsenosidimutans (96.8% 16S rRNA gene sequence similarity), and Flavisolibacter ginsengisoli (96.6%). Growth was observed at 18-37 °C (optimum 30 °C) in R2A medium at pH 7.0. The major cellular fatty acids of strain 17J28-26T were summed feature 3 (C16:1 ω6c and/or C16:1 ω7c), and iso-C15:0. The predominant respiratory quinone was MK-7. The major polar lipid was identified as phosphatidylethanolamine. Based on biochemical, chemotaxonomic and phylogenetic characteristics, strain 17J28-26T represents a novel bacterial species within the family Chitinophagaceae, for which the name Flavisolibacter galbus sp. nov. is proposed. The type strain of Flavisolibacter galbus is 17J28-26T (= KCTC 62222T = JCM 33203T).


Assuntos
Bacteroidetes/classificação , Bacteroidetes/isolamento & purificação , Microbiologia do Solo , Bacteroidetes/genética , Bacteroidetes/fisiologia , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Concentração de Íons de Hidrogênio , Ilhas , Coreia (Geográfico) , Locomoção , Fosfolipídeos/análise , Filogenia , Pigmentos Biológicos/metabolismo , Quinonas/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Temperatura Ambiente
13.
Appl Microbiol Biotechnol ; 103(17): 6973-6987, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31243502

RESUMO

Some of the most important natural pigments have been produced from fungi and used for coloring in food, cosmetics, textiles, and pharmaceutical products. Forty-seven isolates of endophytic fungi were isolated from Cinnamomum zeylanicum in northern Thailand. Only one isolate, CMU-ZY2045, produced an extracellularly red pigment. This isolate was identified as Nigrospora aurantiaca based on morphological characteristics and the molecular phylogenetic analysis of a combined four loci (large subunit and internal transcribed spacer of ribosomal DNA, ß-tubulin, and translation elongation factor 1-alpha genes). The optimum conditions for red pigment production from this fungus were investigated. The results indicated that the highest red pigment yield was observed in the liquid medium containing glucose as a carbon source and yeast extract as a nitrogen source, at a pH value of 5.0 and at 27 °C with shaking for 5 days. The crude red pigment revealed the highest level of solubility in methanol. A fungal red pigment was found to have high stability at temperatures ranging from 20 to 50 °C and pH values at a range of 5.0-6.0. Based on liquid chromatography-mass spectrometry analyses, the red pigment was characterized as bostrycin. The extracted pigment was used for the textile dyeing process. Crude fungal red pigment revealed the highest staining ability in cotton fabrics and displayed excellent fastness to washing, which showing negative cytotoxicity at the concentrations used to cell culture. This is the first report on bostrycin production from N. aurantiaca.


Assuntos
Ascomicetos/química , Corantes/metabolismo , Pigmentos Biológicos/metabolismo , Têxteis , Antraquinonas/análise , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/metabolismo , Carbono/análise , Cinnamomum zeylanicum/microbiologia , Corantes/química , Corantes/isolamento & purificação , Meios de Cultura/química , DNA Ribossômico/genética , Genes Fúngicos/genética , Concentração de Íons de Hidrogênio , Metanol/química , Nitrogênio/análise , Filogenia , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação , Solubilidade , Temperatura Ambiente
14.
Microb Pathog ; 134: 103595, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201902

RESUMO

The persistence of pathogenic bacteria in the marine environment has been thoroughly investigated. The potential threat that these microorganisms pose to public health in recreational waters has always been a concern. In this study, the persistence and the response of Pseudomonas aeruginosa ATCC27853 to starvation and osmotic stress were studied after its incubation in sterilized seawater during 12 months. Three different colonial variants were isolated: A7 after one month, and A81 and A82 after 8 months of incubation period. The incubation effect on the bacterial phenotype and genotype were studied by analyzing modifications in morphology, antibiotic and metal resistance, molecular typing (PFGE and MLST), pigment production and virulence factors. The starved variants showed three different colony forms, but an indistinguishable PFGE pattern and belonged to ST155, as P. aeruginosa ATCC27853. The starved variants maintained the susceptibility to the 13 tested antibiotics, with the exception of the imipenem-resistant A82 strain, which also showed a small colony variant phenotype and the highest values of tolerance to the CuSO4 + NaCl combination. Significant differences were detected in the pigment production, the elastase activity and cytotoxic potential of the starved isolates in comparison to P. aeruginosa ATCC27853. Long-term exposure to stress, such as the incubation in seawater, was shown to induce different responses in P. aeruginosa, including virulent and resistant phenotypes.


Assuntos
Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/fisiologia , Água do Mar/microbiologia , Inanição , Estresse Fisiológico/fisiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Sulfato de Cobre/farmacologia , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana/fisiologia , Eletroforese em Gel de Campo Pulsado , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Variação Genética/efeitos dos fármacos , Variação Genética/fisiologia , Genótipo , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Viabilidade Microbiana , Tipagem de Sequências Multilocus , Compostos Orgânicos/metabolismo , Pressão Osmótica , Elastase Pancreática/metabolismo , Fenazinas/metabolismo , Fenótipo , Pigmentos Biológicos/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/genética , Piocianina/metabolismo , Tolerância ao Sal/genética , Tolerância ao Sal/fisiologia , Alinhamento de Sequência , Cloreto de Sódio/farmacologia , Estresse Fisiológico/genética , Fatores de Tempo , Fatores de Virulência
15.
Faraday Discuss ; 216(0): 494-506, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31037282

RESUMO

In addition to (bacterio)chlorophylls, (B)Chls, light-harvesting complexes (LHCs) bind carotenoids, and/or their oxygen derivatives, xanthophylls. Xanthophylls/carotenoids have pivotal functions in LHCs: in stabilization of the structure, as accessory light-harvesting pigments and, probably most importantly, in photoprotection. Xanthophylls are assumed to be involved in the not yet fully understood mechanism of energy-dependent (qE) non-photochemical quenching of Chl fluorescence (NPQ) in higher plants and algae. The so called "xanthophyll cycle" appears to be crucial in this regard. The molecular mechanism(s) of xanthophyll involvement in qE/NPQ have not been established, yet. Moreover, excitation energy transfer (EET) processes involving carotenoids are also difficult to study, due to the fact that transitions between the ground state (S0, 11Ag-) and the lowest excited singlet state (S1, 21Ag-) of carotenoids are optically one-photon forbidden ("dark"). Two-photon excitation spectroscopic techniques have been used for more than two decades to study one-photon forbidden states of carotenoids. In the current study, two-photon excitation profiles of LHCII samples containing different xanthophyll complements were measured in the presumed 11Ag- → 21Ag- (S0 → S1) transition spectral region of the xanthophylls, as well as for isolated chlorophylls a and b in solution. The results indicate that direct two-photon excitation of Chls in this spectral region is dominant over that by xanthophylls. Implications of the results for proposed mechanism(s) of qE/NPQ will be discussed.


Assuntos
Complexos de Proteínas Captadores de Luz/metabolismo , Fótons , Pigmentos Biológicos/metabolismo , Complexos de Proteínas Captadores de Luz/química , Pigmentos Biológicos/química , Espectrometria de Fluorescência
16.
Aquat Toxicol ; 212: 20-27, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31039523

RESUMO

Polybrominated diphenyl ethers (PBDEs), a series of highly persistent organic pollutants (POPs), are ubiquitous in marine ecosystems. As key primary producers, microalgae are of great importance on evaluating the environmental outcome of PBDEs pollution. In this study, the toxic mechanisms of BDE-47 on the marine diatom Thalassiosira pseudonana were evaluated by measuring multiple physiological processes. Three concentrations of BDE-47 (25, 15 and 5 µg L-1) were used along with two controls (blank: no BDE-47 or DMSO; negative control: only DMSO). Experiments lasted 144 h (6 days), in which the actual BDE-47 concentrations, cell densities, nutrient (nitrate and phosphate) uptake, pigment compositions, photosynthetic physiology, cell morphology and cellular contents (organic carbon and nitrogen) were measured at 12-48 h intervals. The toxic mechanisms of BDE-47 on T. pseudonana cells were evaluated by measuring multiple physiological processes including photosynthesis, nutrient uptake, cellular material synthesis and cell cycle progressions. The cell divisions of T. pseudonana were severely inhibited by the stress of BDE-47, but the photosynthetic parameters were much less declined and recovered earlier than the cell divisions in the same BDE-47 treatments. The unsuppressed uptake rates of nutrients, increased cell volume and cellular contents indicated the cellular material synthesis proceeded normally. Finally, we found that the cell cycle was arrested in G2/M phase under the stress of BDE-47, we thus concluded that the inhibition of cell divisions by BDE-47 was not due to the lack of energy or cellular materials, where the cell cycle arrest happened; this might be the most important toxicological outcome.


Assuntos
Diatomáceas/efeitos dos fármacos , Diatomáceas/fisiologia , Éteres Difenil Halogenados/toxicidade , Fenômenos Fisiológicos/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Carbono/metabolismo , Ciclo Celular/efeitos dos fármacos , Diatomáceas/citologia , Diatomáceas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Fotossíntese/efeitos dos fármacos , Complexo de Proteína do Fotossistema II/metabolismo , Pigmentos Biológicos/metabolismo , Estresse Fisiológico/efeitos dos fármacos
17.
Extremophiles ; 23(4): 435-449, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31065815

RESUMO

Hypersaline ecosystems offer unique habitats to microbial populations capable of withstanding extreme stress conditions and producing novel metabolites of commercial importance. Herein, we have characterized for the first time the production of bioactive pigments from newly isolated halophilic bacterial species. Halophilic bacteria were isolated from Khewra Salt Range of Pakistan. Three distinctly colored isolates were selected for pigment production. Selected colonies were identified as Aquisalibacillus elongatus MB592, Salinicoccus sesuvii MB597, and Halomonas aquamarina MB598 based on morphological, biochemical, and physiological evidences as well as 16S rRNA analysis. The optimum pigment production observed at mesophilic condition, nearly neutral pH, and moderate salinity was validated using response surface methodology. Different analytical techniques (UV spectroscopy, infrared spectroscopy, and HPLC) characterized these purified pigments as derivatives of bacterioruberin carotenoids. Antioxidant activity of pigments revealed up to 85% free-radical scavenging activity at the concentration of 30 µg ml-1. Pigments also showed significant antimicrobial activity against Bacillus subtilis, Bacillus pumilus, Enterococcus faecalis, Bacillus cereus, Klebsiella pneumoniae, Alcaligenes faecalis, Pseudomonas geniculata, Enterococcus faecium, Aspergillus fumigatus, Aspergillus flavus, Fusarium solani, and Mucor spp., suggesting potential biomedical applications.


Assuntos
Anti-Infecciosos/metabolismo , Bacillaceae/metabolismo , Carotenoides/metabolismo , Depuradores de Radicais Livres/metabolismo , Halomonas/metabolismo , Pigmentos Biológicos/metabolismo , Anti-Infecciosos/farmacologia , Carotenoides/farmacologia , Depuradores de Radicais Livres/farmacologia , Pigmentos Biológicos/farmacologia , Tolerância ao Sal
18.
Faraday Discuss ; 216(0): 38-56, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31062011

RESUMO

Synchronisation is a collective phenomenon widely investigated in classical oscillators and, more recently, in quantum systems. However it remains unclear what features distinguish synchronous behaviour in these two scenarios. Recent works have shown that investigating synchronisation dynamics in open quantum systems can give insight into this issue. Here we study transient synchronisation in a bio-inspired vibronic dimer, where electronic excitation dynamics is mediated by coherent interactions with intramolecular vibrational modes. We show that the synchronisation dynamics of local mode displacements exhibit a rich behaviour which arises directly from the distinct time-evolutions of different vibronic quantum coherences. Furthermore, our study shows that coherent energy transport in this bio-inspired system is concomitant with the emergence of positive synchronisation between mode displacements. Our work provides further understanding of the relations between quantum coherence and synchronisation in open quantum systems and suggests an interesting role for coherence in biomolecules, that of promoting synchronisation of vibrational motions driven out of thermal equilibrium.


Assuntos
Pigmentos Biológicos/química , Proteínas/química , Teoria Quântica , Dimerização , Transferência de Energia , Fotossíntese , Pigmentos Biológicos/metabolismo , Proteínas/metabolismo , Vibração
19.
J Microbiol Biotechnol ; 29(6): 897-904, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31091861

RESUMO

Monascus purpureus recombinant mppC and mpp7 knockout strains were subjected to extractive fermentation in the context of azaphilone pigment production. Inclusion of Diaion HP-20 resin resulted in the selective production of unreduced azaphilone congeners, in addition to the early intermediate FK17-P2a, from ∆mppC and ∆mpp7 strains that would otherwise mainly produce reduced congeners. Structural determination of two novel unreduced azaphilones from the ∆mpp7 strain was accomplished. The unreduced azaphilone compound was converted into the cognate reduced congener in recombinant M. purpureus strains, demonstrating its intermediate role in azaphilone biosynthesis. This study demonstrates the possibility that extractive fermentation with Diaion HP-20 resin can be used to obtain cryptic azaphilone metabolites.


Assuntos
Benzopiranos/metabolismo , Microbiologia Industrial/métodos , Monascus/genética , Monascus/metabolismo , Pigmentos Biológicos/metabolismo , Poliestirenos/metabolismo , Benzopiranos/química , Vias Biossintéticas , Fermentação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Deleção de Genes , Oxirredução , Pigmentos Biológicos/química
20.
Antonie Van Leeuwenhoek ; 112(10): 1465-1475, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31119412

RESUMO

A pink pigmented, Gram-negative, rod-shaped, non-spore-forming bacterium (strain 36B243T), was isolated from the spleen of a black rock cod (Notothenia coriiceps, Richardson 1844) in the Chilean Antarctica. Strain 36B243T has a 5.26 Mb chromosome with a DNA G + C content of 35.4 mol%. The draft genome includes the prediction and annotation of 4585 coding genes, and 46 tRNA, 1 tmRNA, and 2735 hypothetical proteins. Phylogenetic analysis based on the 16S rRNA gene sequence placed strain 36B243T into the genus Pedobacter with high sequence similarity to the type strains of Pedobacter sandarakinus (97.5%) and Pedobacter petrophilus (97.1%). Sequence similarities to type strains of all other current Pedobacter species were below 97.1%. Predominant fatty acids are summed feature 3 (C16:1ω7c and/or C16:1ω6c) and iso-C15:0 followed by iso-C17:0 3-OH and C16:0. The major respiratory quinone was menaquinone MK-7. The polar lipid profile contained the major lipids phosphatidylethanolamine, five unidentified aminolipids, two lipids lacking a functional group and two minor glycolipids and one lipid lacking a functional group. An alkali-stable lipid was present. The polyamine pattern contained the predominant compound sym-homospermidine. Characterization by 16S rRNA gene sequence analysis, physiological parameters, pigment analysis, ubiquinone, polar lipid, and fatty acid composition revealed that strain 36B243T represents a new species of the genus Pedobacter. For this reason, we propose the name Pedobacter nototheniae sp. nov. with the type strain 36B243T (= LMG 30634T = CCM 8855T = CIP 111622T).


Assuntos
Pedobacter/classificação , Pedobacter/isolamento & purificação , Perciformes/microbiologia , Baço/microbiologia , Animais , Regiões Antárticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Chile , Análise por Conglomerados , Citosol/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Genoma Bacteriano , Glicolipídeos/análise , Pedobacter/genética , Pedobacter/fisiologia , Fosfolipídeos/análise , Filogenia , Pigmentos Biológicos/metabolismo , Quinonas/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análise
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