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91.
92.
Liliana Catherine Pati?o Rajani Battu Oscar Ortega-Recalde Jeyabalan Nallathambi Venkata Ramana Anandula Umashankar Renukaradhya Paul Laissue 《PloS one》2014,9(10)
The neuronal ceroid-lipofuscinoses (NCL) is a group of neurodegenerative disorders characterized by epilepsy, visual failure, progressive mental and motor deterioration, myoclonus, dementia and reduced life expectancy. Classically, NCL-affected individuals have been classified into six categories, which have been mainly defined regarding the clinical onset of symptoms. However, some patients cannot be easily included in a specific group because of significant variation in the age of onset and disease progression. Molecular genetics has emerged in recent years as a useful tool for enhancing NCL subtype classification. Fourteen NCL genetic forms (CLN1 to CLN14) have been described to date. The variant late-infantile form of the disease has been linked to CLN5, CLN6, CLN7 (MFSD8) and CLN8 mutations. Despite advances in the diagnosis of neurodegenerative disorders mutations in these genes may cause similar phenotypes, which rends difficult accurate candidate gene selection for direct sequencing. Three siblings who were affected by variant late-infantile NCL are reported in the present study. We used whole-exome sequencing, direct sequencing and in silico approaches to identify the molecular basis of the disease. We identified the novel c.1219T>C (p.Trp407Arg) and c.1361T>C (p.Met454Thr) MFSD8 pathogenic mutations. Our results highlighted next generation sequencing as a novel and powerful methodological approach for the rapid determination of the molecular diagnosis of NCL. They also provide information regarding the phenotypic and molecular spectrum of CLN7 disease. 相似文献
93.
Nick Van Reet Hélène Van de Vyver Patient Pati Pyana Anne Marie Van der Linden Philippe Büscher 《PLoS neglected tropical diseases》2014,8(8)
Background
Genetic engineering with luciferase reporter genes allows monitoring Trypanosoma brucei (T.b.) infections in mice by in vivo bioluminescence imaging (BLI). Until recently, luminescent T.b. models were based on Renilla luciferase (RLuc) activity. Our study aimed at evaluating red-shifted luciferases for in vivo BLI in a set of diverse T.b. strains of all three subspecies, including some recently isolated from human patients.Methodology/Principal findings
We transfected T.b. brucei, T.b. rhodesiense and T.b. gambiense strains with either RLuc, click beetle red (CBR) or Photinus pyralis RE9 (PpyRE9) luciferase and characterised their in vitro luciferase activity, growth profile and drug sensitivity, and their potential for in vivo BLI. Compared to RLuc, the red-shifted luciferases, CBR and PpyRE9, allow tracking of T.b. brucei AnTaR 1 trypanosomes with higher details on tissue distribution, and PpyRE9 allows detection of the parasites with a sensitivity of at least one order of magnitude higher than CBR luciferase. With CBR-tagged T.b. gambiense LiTaR1, T.b. rhodesiense RUMPHI and T.b. gambiense 348 BT in an acute, subacute and chronic infection model respectively, we observed differences in parasite tropism for murine tissues during in vivo BLI. Ex vivo BLI on the brain confirmed central nervous system infection by all luminescent strains of T.b. brucei AnTaR 1, T.b. rhodesiense RUMPHI and T.b. gambiense 348 BT.Conclusions/Significance
We established a genetically and phenotypically diverse collection of bioluminescent T.b. brucei, T.b. gambiense and T.b. rhodesiense strains, including drug resistant strains. For in vivo BLI monitoring of murine infections, we recommend trypanosome strains transfected with red-shifted luciferase reporter genes, such as CBR and PpyRE9. Red-shifted luciferases can be detected with a higher sensitivity in vivo and at the same time they improve the spatial resolution of the parasites in the entire body due to the better kinetics of their substrate D-luciferin. 相似文献94.
Wayne Reeve Julie Ardley Rui Tian Sofie De Meyer Jason Terpolilli Vanessa Melino Ravi Tiwari Ronald Yates Graham O’Hara John Howieson Mohamed Ninawi Xiaojing Zhang David Bruce Chris Detter Roxanne Tapia Cliff Han Chia-Lin Wei Marcel Huntemann James Han I-Min Chen Konstantinos Mavromatis Victor Markowitz Ernest Szeto Natalia Ivanova Ioanna Pagani Amrita Pati Lynne Goodwin Tanja Woyke Nikos Kyrpides 《Standards in genomic sciences》2014,9(3):540-550
Microvirga lotononidis is a recently described species of root-nodule bacteria that is an effective nitrogen- (N2) fixing microsymbiont of the symbiotically specific African legume Listia angolensis (Welw. ex Bak.) B.-E. van Wyk & Boatwr. M. lotononidis possesses several properties that are unusual in root-nodule bacteria, including pigmentation and the ability to grow at temperatures of up to 45°C. Strain WSM3557T is an aerobic, motile, Gram-negative, non-spore-forming rod isolated from a L. angolensis root nodule collected in Chipata, Zambia in 1963. This is the first report of a complete genome sequence for the genus Microvirga. Here we describe the features of Microvirga lotononidis strain WSM3557T, together with genome sequence information and annotation. The 7,082,538 high-quality-draft genome is arranged in 18 scaffolds of 104 contigs, contains 6,956 protein-coding genes and 84 RNA-only encoding genes, and is one of 20 rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Community Sequencing Program. 相似文献
95.
Spyridon Ntougias Alla Lapidus James Han Konstantinos Mavromatis Amrita Pati Amy Chen Hans-Peter Klenk Tanja Woyke Constantinos Fasseas Nikos C. Kyrpides Georgios I. Zervakis 《Standards in genomic sciences》2014,9(3):783-793
Olivibacter sitiensis Ntougias et al. 2007 is a member of the family Sphingobacteriaceae, phylum Bacteroidetes. Members of the genus Olivibacter are phylogenetically diverse and of significant interest. They occur in diverse habitats, such as rhizosphere and contaminated soils, viscous wastes, composts, biofilter clean-up facilities on contaminated sites and cave environments, and they are involved in the degradation of complex and toxic compounds. Here we describe the features of O. sitiensis AW-6T, together with the permanent-draft genome sequence and annotation. The organism was sequenced under the Genomic Encyclopedia for Bacteria and Archaea (GEBA) project at the DOE Joint Genome Institute and is the first genome sequence of a species within the genus Olivibacter. The genome is 5,053,571 bp long and is comprised of 110 scaffolds with an average GC content of 44.61%. Of the 4,565 genes predicted, 4,501 were protein-coding genes and 64 were RNA genes. Most protein-coding genes (68.52%) were assigned to a putative function. The identification of 2-keto-4-pentenoate hydratase/2-oxohepta-3-ene-1,7-dioic acid hydratase-coding genes indicates involvement of this organism in the catechol catabolic pathway. In addition, genes encoding for β-1,4-xylanases and β-1,4-xylosidases reveal the xylanolytic action of O. sitiensis. 相似文献
96.
Robert Walker Elizabeth Watkin Rui Tian Lambert Br?u Graham O’Hara Lynne Goodwin James Han Elizabeth Lobos Marcel Huntemann Amrita Pati Tanja Woyke Konstantinos Mavromatis Victor Markowitz Natalia Ivanova Nikos Kyrpides Wayne Reeve 《Standards in genomic sciences》2014,9(3):551-561
Burkholderia sp. strain WSM2230 is an aerobic, motile, Gram-negative, non-spore-forming acid-tolerant rod isolated from acidic soil collected in 2001 from Karijini National Park, Western Australia, using Kennedia coccinea (Coral Vine) as a host. WSM2230 was initially effective in nitrogen-fixation with K. coccinea, but subsequently lost symbiotic competence. Here we describe the features of Burkholderia sp. strain WSM2230, together with genome sequence information and its annotation. The 6,309,801 bp high-quality-draft genome is arranged into 33 scaffolds of 33 contigs containing 5,590 protein-coding genes and 63 RNA-only encoding genes. The genome sequence of WSM2230 failed to identify nodulation genes and provides an explanation for the observed failure of the laboratory grown strain to nodulate. The genome of this strain is one of 100 sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project. 相似文献
97.
Patiño-Molina Rosario Martín-Martínez Mercedes Herranz Rosario García-López Maria Teresa González-Muñiz Rosario 《International journal of peptide research and therapeutics》2000,7(3):143-149
Summary β-Keto esters derived from dipeptides are prepared by application of common methodologies employed for the synthesis of amino
acid-derived β-keto esters; however, epimerization of the C-terminal residue occurred to different extents depending on the
method. In imidazolide activated dipeptides, this epimerization is due to the CDI activation step and to the configurational
instability of the intermediate imidazolides in different reaction media. Regarding yield and diastereomeric purity, the method
of choice proved to be the reaction of dipeptide-derived imidazolide with the potassium salt of malonic half esters in the
presence of MgCl2. 相似文献
98.
Growth Rate of the Microalga Tetraselmis suecica Changes the Biochemical Composition of Artemia Species 总被引:1,自引:0,他引:1
The impact of different microalgal semicontinuous cultures on growth and biochemical composition in the next link of the
food chain was tested using the filter feeder Artemia species as a model. The marine microalga Tetraselmis suecica was cultured semicontinuously with renewal rates between 10% and 50% and used to feed Artemia. Microalgal cultures maintained with a low renewal rate that had biochemical composition similar to that of the stationary-phase
cultures commonly used in aquaculture produced poor growth and survival and low food-conversion efficiency compared to cultures
maintained with a high renewal rate. Changes in the renewal rate in microalgal cultures also resulted in important changes
in the gross biochemical composition of the filter feeder. The gross biochemical composition of the Artemia resembled that of the microalgae used as food except for total lipid content. The percentage of protein in the organic fraction
of Artemia increased from 45% to 65% of the organic weight with increasing renewal rates in the microalgal cultures, while the carbohydrate
percentage decreased under the same conditions. Higher renewal rates resulted in higher lipid percentages in the microalga,
but in Artemia the percentage of lipids decreased from 19% of the organic weight with a renewal rate of 10%, to 13% with a renewal rate
of 50%. The percentage of all polyunsaturated fatty acids in Artemia, including 20:5n-3, increased slightly with increasing renewal rates in the microalgal cultures. Results emphasize the importance
of controlling microalgal nutritional value for the success of aquaculture food chains in which filter feeders are involved.
Received October 15, 2000; accepted December 29, 2000. 相似文献
99.
J. Fábregas E. D. Morales N. Polanco M. Patiño A. Otero J. F. Tobar 《World journal of microbiology & biotechnology》1996,12(1):47-49
The marine microalga Phaeodactylum tricornutum was cultivated in semi-continuous culture under mixotrophic conditions with the soluble fractions of potato, rye and wheat flours that had been naturally fermented, at 2% or 4% (w/v). The rye flour produced the highest microalgal cellular density of 90×106 cells.ml-1 when supplemented with NaNO3 and NaH2PO4. The autotrophic control only gave 57×106 cells.ml-1. The value of agricultural surpluses, such as rye flour, can therefore be increased by its use in the production of valuable, microalgal biomass which is rich in protein, pigments and fatty acids. 相似文献
100.
LYNN RANÅKER MIKAEL JÖNSSON P. ANDERS NILSSON CHRISTER BRÖNMARK 《Freshwater Biology》2012,57(9):1761-1768
1. Environmental changes such as eutrophication and increasing inputs of humic matter (brownification) may have strong effects on predator–prey interactions in lakes through a reduction in the visual conditions affecting foraging behaviour of visually oriented predators. 2. In this experiment, we studied the effects of visual range (25–200 cm) in combination with optically deteriorating treatments (algae, clay or brown humic water) on predator–prey interactions between pike (Esox lucius) and roach (Rutilus rutilus). We measured effects on reaction distance and strike distance for pike and escape distance for roach, when pike individuals were exposed to free‐swimming roach as well as to roach held in a glass cylinder. 3. We found that reaction distance decreased with decreasing visual range caused by increasing levels of algae, clay or humic matter. The effect of reaction distance was stronger in turbid water (clay, algae) than in the brown water treatment. 4. Strike distance was neither affected by visual range nor by optical treatment, but we found shorter strike distances when pike attacked roach using visual cues only (roach held in a cylinder) compared to when pike could use multiple senses (free‐swimming roach). Escape distance for roach was longer in turbid than in brown water treatments. 5. Changes in environmental drivers, such as eutrophication and brownification, affecting the optical climate should thus have consequences for the strength of predator–prey interactions through changes in piscivore foraging efficiency and prey escape behaviour. This in turn may affect lake ecosystems through higher‐order interactions. 相似文献