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Wenjin Hu, Xinli Pan, Hafiz Muhammad Khalid Abbas, Fengfeng Li, Wubei Dong
Rhizoctonia solani is a causative agent of sheath blight, which results in huge economic losses every year. During its life cycle, the formation of sclerotia helps Rhizoctonia solani withstand a variety of unfavorable factors. Oxidative stress is a key factor that induces sclerotium formation. The differentiated and undifferentiated phenotypes of R. solani AG-1-IA were obtained by controlling aerial conditions. Metabolomics based on the mass spectrometry technique combined with multivariate and univariate analyses was used to investigate the metabolic variation in vegetative, differentiated and undifferentiated mycelia...
2017: PloS One
Pablo Villarreal, Mario Carrasco, Salvador Barahona, Jennifer Alcaíno, Víctor Cifuentes, Marcelo Baeza
Yeasts colonizing the Antarctic region are exposed to a high ultraviolet radiation evolving mechanisms to minimize the UV radiation damages, such as the production of UV-absorbing or antioxidant compounds like carotenoid pigments and mycosporines. Ergosterol has also been suggested to play a role in this response. These compounds are also economically attractive for several industries such as pharmaceutical and food, leading to a continuous search for biological sources of them. In this work, the UV-C radiation tolerance of yeast species isolated from the sub-Antarctic region and their production of carotenoids, mycosporines, and ergosterol were evaluated...
January 2016: Current Microbiology
Tae Hyug Jeong, Keunho Ji, Young Tae Kim
Lycopene cyclase converts lycopene to beta-carotene by catalyzing the formation of two beta-rings at each end of the linear carotene structure. This reaction takes place as a two-step reaction in which both sides of of the lycopene molecule are cyclized into beta-carotene rings via the monocyclic gamma-carotene as an intermediate. The crtY gene coding for lycopene cyclase from Paracoccus haeundaensis consists of 1,158 base pairs encoding 386 amino acids residues. An expression plasmid containing the crtY gene (pET44a-CrtY) was constructed and expressed in Escherichia coli, and produced a recombinant protein of approximately 43 kDa, corresponding to the molecular mass of lycopene cyclase...
February 2013: Journal of Microbiology and Biotechnology
Sorel Jatunov, Silvia Quesada, Cecilia Díaz, Enrique Murillo
Total carotenoid content and composition of carotenoids of six varieties of Bactris gasipaes were determined by spectrophotometry and HPLC, with photodiode array detector. Significant differences in total carotenoid content (1.1 to 22.3 mg/100g) were detected among these varieties. Boiling the fruits for 30 minutes did not affect total carotenoid content, but did change the amount of some specific carotenoids, mainly by the production of Z-isomers. Peach palm varieties had the same carotenoids, but in different proportions, presenting mainly, all E-beta-carotene (26...
March 2010: Archivos Latinoamericanos de Nutrición
Mingbo Lu, Yang'e Zhang, Chunfang Zhao, Pengpeng Zhou, Longjiang Yu
This study presents an HPLC method for simultaneous analysis of astaxanthin and its carotenoid precursors from Xanthophyllomyces dendrorhous. The HPLC method is accomplished by employing a C18 column and the mobile phase methanol/water/acetonitrile/ dichloromethane (70:4:13:13, v/v/v/v). Astaxanthin is quantified by detection at 480 nm. The carotenoid precursors are identified by LC-APCI-MS and UV-vis absorption spectra. Peaks showed in the HPLC chromatogram are identified as carotenoids in the monocyclic biosynthetic pathway or their derivatives...
July 2010: Zeitschrift Für Naturforschung. C, A Journal of Biosciences
Dariusz M Niedzwiedzki, Aaron M Collins, Amy M LaFountain, Miriam M Enriquez, Harry A Frank, Robert E Blankenship
Carotenoids present in the photosynthetic light-harvesting reaction center (LHRC) complex from chlorosome lacking filamentous anoxygenic phototroph, Roseiflexus castenholzii were purified and characterized for their photochemical properties. The LHRC from anaerobically grown cells contains five different carotenoids, methoxy-keto-myxocoxanthin, gamma-carotene, and its three derivatives, whereas the LHRC from aerobically grown cells contains only three carotenoid pigments with methoxy-keto-myxocoxanthin being the dominant one...
July 8, 2010: Journal of Physical Chemistry. B
No abstract text is available yet for this article.
July 1947: Archives of Biochemistry
Marcel Fuciman, Pavel Chábera, Anita Zupcanová, Petr Hríbek, Juan B Arellano, Frantisek Vácha, Jakub Psencík, Tomás Polívka
Excited-state properties of aryl carotenoids, important components of light harvesting antennae of green sulfur bacteria, have been studied by femtosecond transient absorption spectroscopy. To explore effects of the conjugated aryl group, we have studied a series of aryl carotenoids with conjugated phi-ring, chlorobactene, beta-isorenieratene and isorenieratene, and compared them with their non-aryl counterparts gamma-carotene and beta-carotene, which contain beta-ring. Changing beta-ring to phi-ring did not reveal any changes in absorption spectra, indicating negligible effect of the phi-ring on the effective conjugation length...
April 7, 2010: Physical Chemistry Chemical Physics: PCCP
M Varzakakou, T Roukas
The identification of carotenoids in B. trispora during pigment production from deproteinized hydrolyzed whey supplemented with plant oils was studied. The carotenoid content in Blakeslea trispora were beta-carotene, gamma-carotene, and lycopene. The composition of carotenoids depends of the amount of oils added to the cheese whey. At the maximum concentration of carotenoids, the proportions of beta-carotene, gamma-carotene, and lycopene (as percent of total carotenoids) was 60.1%, 32.5%, and 7.4%, respectively...
2010: Preparative Biochemistry & Biotechnology
Zongtao Sun, Shaochuan Shen, Bing Tian, Hu Wang, Zhenjian Xu, Liangyan Wang, Yuejin Hua
Deinococcus radiodurans strain R1 synthesizes a unique ketocarotenoid product named deinoxanthin. The detailed steps involved in the biosynthesis of deinoxanthin remain unresolved. A carotene ketolase homologue encoded by dr0093 was inactivated by gene mutation to verify its function in the native host D. radiodurans. Analysis of the carotenoids in the resultant mutant R1DeltacrtO demonstrated that dr0093 encodes gamma-carotene ketolase (CrtO) catalysing the introduction of one keto group into the C-4 position of gamma-carotene derivatives to form ketolated carotenoids...
November 2009: FEMS Microbiology Letters
Alfonso Prado-Cabrero, Patrick Schaub, Violeta Díaz-Sánchez, Alejandro F Estrada, Salim Al-Babili, Javier Avalos
Carotenoids are widespread terpenoid pigments with applications in the food and feed industries. Upon illumination, the gibberellin-producing fungus Fusarium fujikuroi (Gibberella fujikuroi mating population C) develops an orange pigmentation caused by an accumulation of the carboxylic apocarotenoid neurosporaxanthin. The synthesis of this xanthophyll includes five desaturation steps presumed to be catalysed by the carB-encoded phytoene desaturase. In this study, we identified a yellow mutant (SF21) by mutagenesis of a carotenoid-overproducing strain...
August 2009: FEBS Journal
Zongtao Sun, Shaochuan Shen, Chao Wang, Hu Wang, Yaping Hu, Jiandong Jiao, Tingting Ma, Bing Tian, Yuejin Hua
A novel carotenoid 1,2-hydratase (CruF) responsible for the C-1',2' hydration of gamma-carotene was identified in the non-photosynthetic bacteria Deinococcus radiodurans R1 and Deinococcus geothermalis DSM 11300. Gene expression and disruption experiments demonstrated that dr0091 and dgeo2309 encode CruF in D. radiodurans and D. geothermalis, respectively. Their homologues were also found in the genomes of cyanobacteria, and exhibited little homology to the hydroxyneurosporene synthase (CrtC) proteins found mainly in photosynthetic bacteria...
August 2009: Microbiology
Yeong-Su Kim, Nam-Hee Kim, Soo-Jin Yeom, Seon-Won Kim, Deok-Kun Oh
Codon optimization was used to synthesize the blh gene from the uncultured marine bacterium 66A03 for expression in Escherichia coli. The expressed enzyme cleaved beta-carotene at its central double bond (15,15') to yield two molecules of all-trans-retinal. The molecular mass of the native purified enzyme was approximately 64 kDa as a dimer of 32-kDa subunits. The K(m), k(cat), and k(cat)/K(m) values for beta-carotene as substrate were 37 mum, 3.6 min(-1), and 97 mm(-1) min(-1), respectively. The enzyme exhibited the highest activity for beta-carotene, followed by beta-cryptoxanthin, beta-apo-4'-carotenal, alpha-carotene, and gamma-carotene in decreasing order, but not for beta-apo-8'-carotenal, beta-apo-12'-carotenal, lutein, zeaxanthin, or lycopene, suggesting that the presence of one unsubstituted beta-ionone ring in a substrate with a molecular weight greater than C(35) seems to be essential for enzyme activity...
June 5, 2009: Journal of Biological Chemistry
Luciana Y Tomita, Lana C Almeida, Cecília Roteli-Martins, Vania D'Almeida, Marly A Cardoso et al.
OBJECTIVE: Dietary intake and nutritional status of antioxidant vitamins have been reported to protect against some cancers. The objective of the present study was to assess the correlations between serum levels of carotenoids (including beta-, alpha- and gamma-carotene), lycopene, retinol, alpha- and gamma-tocopherols, and dietary intakes estimated by an FFQ, among low-income women in the Brazilian Investigation into Nutrition and Cervical Cancer Prevention (BRINCA) study. DESIGN: Cross-sectional study of data for 918 women aged 21-65 years participating in the BRINCA study in São Paulo city...
November 2009: Public Health Nutrition
Aaron M Collins, Yueyong Xin, Robert E Blankenship
The light-harvesting-reaction center (LHRC) complex from the chlorosome-lacking filamentous anoxygenic phototroph (FAP), Roseiflexus castenholzii (R. castenholzii) was purified and characterized for overall pigment organization. The LHRC is a single complex that is comprised of light harvesting (LH) and reaction center (RC) polypeptides as well as an attached c-type cytochrome. The dominant carotenoid found in the LHRC is keto-gamma-carotene, which transfers excitation to the long wavelength antenna band with 35% efficiency...
August 2009: Biochimica et Biophysica Acta
Andrea Ilg, Peter Beyer, Salim Al-Babili
Carotenoid cleavage products--apocarotenoids--include biologically active compounds, such as hormones, pigments and volatiles. Their biosynthesis is initiated by the oxidative cleavage of C-C double bonds in carotenoid backbones, leading to aldehydes and/or ketones. This step is catalyzed by carotenoid oxygenases, which constitute an ubiquitous enzyme family, including the group of plant carotenoid cleavage dioxygenases 1 (CCD1s), which mediates the formation of volatile C(13) ketones, such as beta-ionone, by cleaving the C9-C10 and C9'-C10' double bonds of cyclic and acyclic carotenoids...
February 2009: FEBS Journal
Gerhard Sandmann, Shinishi Takaichi, Paul D Fraser
The Neurospora crassa mutant YLO exhibits a yellow phenotype instead of the red-orange pigmentation of the wild type. Recently, it was shown that the mutant YLO is defective in a specific aldehyde dehydrogenase which catalyses the last step of carotenogenesis to the formation of neurosporaxanthin [Estrada, A.F., Youssar, L., Scherzinger, D., Al-Babili, S., Avalos, J., 2008. The ylo-1 gene encodes an aldehyde dehydrogenase responsible for the last reaction in the Neurospora carotenoid pathway. Mol. Microbiol...
December 2008: Phytochemistry
Yeong-Su Kim, Deok-Kun Oh
The recombinant beta-carotene 15,15'-monooxygenase from chicken liver was purified as a single 60 kDa band by His-Trap HP and Resource Q chromatography. It had a molecular mass of 240 kDa by gel filtration indicating the native form to be tetramer. The enzyme converted beta-carotene under maximal conditions (pH 8.0 and 37 degrees C) with a k (cat) of 1.65 min(-1) and a K (m) of 26 muM and its conversion yield of beta-carotene to retinal was 120% (mol mol(-1)). The enzyme displayed catalytic efficiency and conversion yield for beta-carotene, beta-cryptoxanthin, beta-apo-8'-carotenal, beta-apo-4'-carotenal, alpha-carotene and gamma-carotene in decreasing order but not for zeaxanthin, lutein, beta-apo-12'-carotenal and lycopene, suggesting that the presence of one unsubstituted beta-ionone ring in a substrate with a molecular weight greater than C(30) seems to be essential for enzyme activity...
March 2009: Biotechnology Letters
Shinichi Takaichi, Takashi Maoka, Naoshige Akimoto, Marvelisa L Carmona, Yukiho Yamaoka
We isolated a strain of Corynebacterineae from surface seawater from the Inland Sea of Japan. This strain, AIST-1, was determined to be a strain of Gordonia terrae based on its 16S rRNA gene sequence. The colony was red-colored, and the pigments were identified to be carotenoid derivatives. The structures of two major carotenoids were (2'S)-deoxymyxol 1'-glucoside, a dihydroxyl derivative of gamma-carotene with 12 conjugated double bonds, and (2'S)-4-ketodeoxymyxol 1'-glucoside. Their glucosyl acyl esters and mycoloyl esters were also identified...
October 2008: Bioscience, Biotechnology, and Biochemistry
Ornella M Porcu, Delia B Rodriguez-Amaya
The indigenous pitanga (Eugenia uniflora L.) is now marketed and commercially processed in Brazil. In the present work, the carotenoids of the pitanga fruit from two states and at two stages of ripening, as well as of processed pitanga products (frozen pulp and juice, the brands being designated as A, B and C) commercialized in Campinas, São Paulo, were determined by HPLC. As compared to ripe pitanga from Medianeira, Paraná, those from Campinas had significantly higher (all-E)-lycopene (14.0 vs. 71.1 microg/g), (13Z)-lycopene (1...
December 2008: Plant Foods for Human Nutrition
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