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Kenjiro Sugiyama, Masashi Ebisawa, Masaharu Yamada, Yoshiki Nagashima, Hideyuki Suzuki, Takashi Maoka, Shinichi Takaichi
The genus Arthrospira is filamentous, non-nitrogen-fixing cyanobacteria that is commercially important. We identified the molecular structures of carotenoids in Arthrospira platensis NIES-39. The major carotenoid identified was β-carotene. In addition, the hydroxyl derivatives of β-cryptoxanthin and (3R,3'R)-zeaxanthin were also found to be present. The carotenoid glycosides were identified as (3R,2'S)-myxol 2'-methylpentoside and oscillol 2,2'-dimethylpentoside. The methylpentoside moiety was a mixture of fucoside and chinovoside in an approximate ratio of 1 : 4...
April 1, 2017: Plant & Cell Physiology
Wenyi Sun, Xiaobing Yang, Xueying Wang, Xinping Lin, Yanan Wang, Sufang Zhang, Yushi Luan, Zongbao K Zhao
OBJECTIVES: To target a carotenoid biosynthetic gene in the oleaginous yeast Rhodosporidium toruloides by using the Agrobacterium-mediated transformation (AMT) method. RESULTS: The RHTO_04602 locus of R. toruloides NP11, previously assigned to code the carotenoid biosynthetic gene CRTI, was amplified from genomic DNA and cloned into the binary plasmid pZPK-mcs, resulting in pZPK-CRT. A HYG-expression cassette was inserted into the CRTI sequence of pZPK-CRT by utilizing the restriction-free clone strategy...
March 23, 2017: Biotechnology Letters
Pingping Zhou, Wenping Xie, Aipeng Li, Fan Wang, Zhen Yao, Qi Bian, Yongqiang Zhu, Hongwei Yu, Lidan Ye
Highly efficient biosynthesis of the commercially valuable carotenoid astaxanthin by microbial cells is an attractive alternative to chemical synthesis and microalgae extraction. With the goal of enhancing heterologous astaxanthin production in Saccharomyces cerevisiae, metabolic engineering and protein engineering were integrated to improve both the expression and activity of rate-limiting enzymes. Firstly, to increase the supply of β-carotene as a key precursor for astaxanthin, a positive mutant of GGPP synthase (CrtE03M) was overexpressed together with three other rate-limiting enzymes tHMG1, CrtI and CrtYB...
May 2017: Enzyme and Microbial Technology
Hendrik Pollmann, Jürgen Breitenbach, Gerhard Sandmann
Phytoene is a colorless carotenoid with increasing economic potential for skin care but with limited availability. The red yeast Xanthophyllomyces dendrorhous which has previously been used as a production platform for carotenoids was engineered as a prototype for the yield of this carotene. Phytoene was accumulated by prevention of its metabolization by desaturation in the carotenoid pathway. In a first step, the phytoene desaturase gene crtI was disrupted by insertion of a hygromycin-resistance gene. Most of the resulting transformants were heterozygote for intact and inactivated crtI...
April 10, 2017: Journal of Biotechnology
Jie Wu, Aihua Deng, Qinyun Sun, Hua Bai, Zhaopeng Sun, Xiuling Shang, Yun Zhang, Qian Liu, Yong Liang, Shuwen Liu, Yongsheng Che, Tingyi Wen
Manipulating the bacterial genomes in an efficient manner is essential to biological and biotechnological research. Here, we reprogrammed the bacterial TA systems as the toxin counter-selectable cassette regulated by an antitoxin switch (TCCRAS) for genetic modifications in the extensively studied and utilized Gram-positive bacteria, B. subtilis and Corynebacterium glutamicum. In the five characterized type II TA systems, the RelBE complex can specifically and efficiently regulate cell growth and death by the conditionally controlled antitoxin RelB switch, thereby serving as a novel counter-selectable cassette to establish the TCCRAS system...
January 26, 2017: ACS Synthetic Biology
Haritha Bollinedi, Gopala Krishnan S, Kumble Vinod Prabhu, Nagendra Kumar Singh, Sushma Mishra, Jitendra P Khurana, Ashok Kumar Singh
Homozygous Golden Rice lines developed in the background of Swarna through marker assisted backcross breeding (MABB) using transgenic GR2-R1 event as a donor for the provitamin A trait have high levels of provitamin A (up to 20 ppm) but are dwarf with pale green leaves and drastically reduced panicle size, grain number and yield as compared to the recurrent parent, Swarna. In this study, we carried out detailed morphological, biochemical and molecular characterization of these lines in a quest to identify the probable reasons for their abnormal phenotype...
2017: PloS One
Eugenia M A Enfissi, Marilise Nogueira, Peter M Bramley, Paul D Fraser
Carotenoid biosynthesis in plants includes a complex series of desaturation/isomerisation reactions, catalyzed by four independent enzymes. In bacteria and fungi one desaturase/isomerase enzyme completes the same series of reactions. In the present study, a bacterial desaturase (crtI) from Pantoea ananatis has been overexpressed in the tangerine mutant of tomato (Solanum lycopersicon) which accumulates cis-carotene isomers in the fruit due to a defective isomerase (CRTISO) and the old gold crimson (og(c) ) tomato mutant, which is defective in the fruit-enhanced lycopene β-cyclase (CYCB)...
November 19, 2016: Plant Journal: for Cell and Molecular Biology
Xiangrong Dong, Yanping Wang, Fengyuan Yang, Shanshan Zhao, Bing Tian, Tao Li
OBJECTIVES: Lycopene biosynthetic genes from Deinococcus radiodurans were co-expressed in Lactococcus lactis to produce lycopene and improve its tolerance to stress. RESULTS: Lycopene-related genes from D. radiodurans, DR1395 (crtE), DR0862 (crtB), and DR0861 (crtI), were fused in line with S hine-Dalgarno (SD) sequences and co-expressed in L. lactis. The recombinant strain produced 0.36 mg lycopene g(-1) dry cell wt after 48 h fermentation. The survival rate to UV irradiation of the recombinant strain was higher than that of the non-transformed strain...
January 2017: Biotechnology Letters
Muhammad Zubair Khan, Miho Takemura, Takashi Maoka, Motoyasu Otani, Norihiko Misawa
Sweetpotato Ipomoea batatas is known as a hexaploid species. Here, we analyzed carotenoids contained in the leaves and tubers of sweetpotato cultivars 'White Star' (WS) and W71. These cultivars were found to contain several carotenoids unique to sweetpotato tubers such as β-carotene-5,6,5',8'-diepoxide and β-carotene-5,8-epoxide. Next, we isolated two kinds of carotene cyclase genes that encode lycopene β- and ε-cyclases from the WS and W71 leaves, by RT-PCR and subsequent RACE. Two and three lycopene β-cyclase gene sequences were, respectively, isolated from WS, named IbLCYb1, 2, and from W71, IbLCYb3, 4, 5...
September 1, 2016: Zeitschrift Für Naturforschung. C, A Journal of Biosciences
Ashok Ganapathy, Sridhar Jayavel, Sivakumar Natesan
Planococcus maritimus MKU009 is a Gram positive cocci and a moderate halophilic bacterium isolated from marine water of Pichavaram, South East Coast of India. Here we report the draft genome of Planococcus maritimus MKU009 with a total size of 3,251,644 bp with N50 value of 1681571 bp. The overall G+C content of the genome was 47.27%. The carotenoid producing crtN, crtB, crtP and crtI genes were located within the first contig of the genome assembly. This genome source will provide insights into functional genomics of carotenoid production and metabolic engineering...
2016: Journal of Genomics
Elmedina Dautovic, Carlijn de Roos, Yanda van Rood, Agnes Dommerholt, Roos Rodenburg
PURPOSE: To examine the potential effects of eye movement desensitization and reprocessing (EMDR) in children with epilepsy-related posttraumatic stress and/or anxiety symptoms, using a case series design. METHODS: Five children (aged 8-18) with epilepsy identified for seizure-related posttraumatic stress and/or anxiety symptoms were treated with EMDR. To examine potential treatment effects, posttraumatic stress and anxiety symptoms were assessed (CRTI and SCARED) pre- and post-EMDR and at 3-month follow-up...
2016: European Journal of Psychotraumatology
Nadja A Henke, Sabine A E Heider, Petra Peters-Wendisch, Volker F Wendisch
Astaxanthin, a red C40 carotenoid, is one of the most abundant marine carotenoids. It is currently used as a food and feed additive in a hundred-ton scale and is furthermore an attractive component for pharmaceutical and cosmetic applications with antioxidant activities. Corynebacterium glutamicum, which naturally synthesizes the yellow C50 carotenoid decaprenoxanthin, is an industrially relevant microorganism used in the million-ton amino acid production. In this work, engineering of a genome-reduced C. glutamicum with optimized precursor supply for astaxanthin production is described...
June 30, 2016: Marine Drugs
Chunji Li, Ning Zhang, Jia Song, Na Wei, Bingxue Li, Hongtao Zou, Xiaori Han
Carotenoids are one of the most common classes of natural pigments widely occurring within organisms. These structurally diverse pigments are of great importance in different processes such as nutrition, vision, cellular growth and development. While found in various yeast strains, one of the best-studied carotenoid producer is the pigmented species Sporidiobolus pararoseus. However, the precise nature of the genes involved in the biosynthesis of carotenoids in this species remains unclear. Here, we cloned a cDNA copy of the phytoene desaturase gene crtI from Sporidiobolus pararoseus CGMCC 2...
September 15, 2016: Gene
Yan Chen, Wenhai Xiao, Ying Wang, Hong Liu, Xia Li, Yingjin Yuan
BACKGROUND: Microbial production of lycopene, a commercially and medically important compound, has received increasing concern in recent years. Saccharomyces cerevisiae is regarded as a safer host for lycopene production than Escherichia coli. However, to date, the lycopene yield (mg/g DCW) in S. cerevisiae was lower than that in E. coli and did not facilitate downstream extraction process, which might be attributed to the incompatibility between host cell and heterologous pathway. Therefore, to achieve lycopene overproduction in S...
June 21, 2016: Microbial Cell Factories
Pouya Javidpour, Samuel Deutsch, Vivek K Mutalik, Nathan J Hillson, Christopher J Petzold, Jay D Keasling, Harry R Beller
Ladderanes are hydrocarbon chains with three or five linearly concatenated cyclobutane rings that are uniquely produced as membrane lipid components by anammox (anaerobic ammonia-oxidizing) bacteria. By virtue of their angle and torsional strain, ladderanes are unusually energetic compounds, and if produced biochemically by engineered microbes, could serve as renewable, high-energy-density jet fuel components. The biochemistry and genetics underlying the ladderane biosynthetic pathway are unknown, however, previous studies have identified a pool of 34 candidate genes from the anammox bacterium, Kuenenia stuttgartiensis, some or all of which may be involved with ladderane fatty acid biosynthesis...
2016: PloS One
Lei Wang, Jana Hoffmann, Hildegard Watzlawick, Josef Altenbuchner
We developed a counterselectable deletion system for Thermus thermophilus HB27 based on cytosine deaminase (encoded by codA) from Thermaerobacter marianensis DSM 12885 and the sensitivity of T. thermophilus HB27 to the antimetabolite 5-fluorocytosine (5-FC). The deletion vector comprises the pUC18 origin of replication, a thermostable kanamycin resistance marker functional in T. thermophilus HB27, and codA under the control of a constitutive putative trehalose promoter from T. thermophilus HB27. The functionality of the system was demonstrated by deletion of the bglT gene, encoding a β-glycosidase, and three carotenoid biosynthesis genes, CYP175A1, crtY, and crtI, from the genome of T...
December 11, 2015: Applied and Environmental Microbiology
Lina M Castelblanco-Matiz, Alejandra Barbachano-Torres, Teresa Ponce-Noyola, Ana C Ramos-Valdivia, Carlos M Cerda García-Rojas, César M Flores-Ortiz, Salvador K Barahona-Crisóstomo, Marcelo E Baeza-Cancino, Jennifer Alcaíno-Gorman, Víctor H Cifuentes-Guzmán
The primary carotenoid synthesized by Xanthophyllomyces dendrorhous is astaxanthin, which is used as a feed additive in aquaculture. Cell growth kinetics and carotenoid production were correlated with the mRNA levels of the idi, crtE, crtYB, crtI, crtS and crtR genes, and the changes in gene sequence between the wild-type and a carotenoid overproducer XR4 mutant strain were identified. At the late stationary phase, the total carotenoid content in XR4 was fivefold higher than that of the wild-type strain. Additionally, the mRNA levels of crtE and crtS increased during the XR4 growth and were three times higher than the wild-type strain in the late stationary phase...
December 2015: Archives of Microbiology
Weiyue Jin, Xian Xu, Ling Jiang, Zhidong Zhang, Shuang Li, He Huang
OBJECTIVES: Putative genes crtE, crtB, and crtI from Deinococcus wulumiqiensis R12, a novel species, were identified by genome mining and were co-expressed using the optimized Shine-Dalgarno (SD) regions to improve lycopene yield. RESULTS: A lycopene biosynthesis pathway was constructed by co-expressing these three genes in Escherichia coli. After optimizing the upstream SD regions and the culture medium, the recombinant strain EDW11 produced 88 mg lycopene g(-1) dry cell wt (780 mg lycopene l(-1)) after 40 h fermentation without IPTG induction, while the strain EDW without optimized SD regions only produced 49 mg lycopene g(-1) dry cell wt (417 mg lycopene l(-1))...
November 2015: Biotechnology Letters
Linda J Burns, Charles P Clayton, James N George, Beverly S Mitchell, Scott D Gitlin
PROBLEM: There is a recognized need to translate scientific discoveries to patient-oriented clinical research (POCR). Several obstacles interfere with the successful recruitment and retention of physicians for POCR careers. APPROACH: The American Society of Hematology developed a yearlong educational and mentoring experience, the Clinical Research Training Institute (CRTI), for early-career physician-scientists from multiple institutions throughout the United States and Canada pursuing POCR careers...
August 2015: Academic Medicine: Journal of the Association of American Medical Colleges
Yong Bae Seo, Seong-Seok Choi, Jong Kyu Lee, Nan-Hee Kim, Mi Jin Choi, Jong-Myoung Kim, Tae Hyug Jeong, Soo-Wan Nam, Han Kyu Lim, Gun-Do Kim
A phytoene synthase gene, crtB, was isolated from Kocuria gwangalliensis. The crtB with 1,092 bp full-length has a coding sequence of 948 bp and encodes a 316-amino-acids protein. The deduced amino acid sequence showed a 70.9% identity with a putative phytoene synthase from K. rhizophila. An expression plasmid, pCcrtB, containing the crtB gene was constructed, and E. coli cells containing this plasmid produced the recombinant protein of approximately 34 kDa , corresponding to the molecular mass of phytoene synthase...
November 2015: Journal of Microbiology and Biotechnology
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