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排序方式: 共有415条查询结果,搜索用时 218 毫秒
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Min-Kyoo Shin Edwin Vázquez-Rosa Yeojung Koh Matasha Dhar Kalyani Chaubey Coral J. Cintrón-Pérez Sarah Barker Emiko Miller Kathryn Franke Maria F. Noterman Divya Seth Rachael S. Allen Cara T. Motz Sriganesh Ramachandra Rao Lara A. Skelton Machelle T. Pardue Steven J. Fliesler Chao Wang Andrew A. Pieper 《Cell》2021,184(10):2715-2732.e23
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M. E. W. Hemels E. S. Hoendermis J. P. van Melle P. G. Pieper 《Netherlands heart journal》2011,19(3):107-111
In patients with unexplained hypertension, especially in combination with a cardiac murmur, the presence of an aortic coarctation should always be ruled out given the high morbidity and mortality. However, particularly patients with an isolated coarctation often remain asymptomatic for years and the defect may be unnoticed even until the fifth or sixth decade of life. In the present article, we describe two patients with late detected coarctation to illustrate the clinical consequences, diagnostic clues for earlier detection and current therapeutic options to achieve optimal treatment. The key sign of an aortic coarctation, a difference in arterial blood pressure measured between the upper and lower extremities, should always be examined, followed by echocardiography. We conclude that even in case of a late detected severe coarctation, surgical or percutaneous repair has proven to be feasible and substantially effective, improving quality of life and lowering the risk of further hypertension-associated problems. 相似文献
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Strunecký Otakar Kopejtka Karel Goecke Franz Tomasch Jürgen Lukavský Jaromír Neori Amir Kahl Silke Pieper Dietmar H. Pilarski Plamen Kaftan David Koblížek Michal 《Extremophiles : life under extreme conditions》2019,23(1):35-48
Extremophiles - Genotypic and morphological diversity of cyanobacteria in the Rupite hot spring (Bulgaria) was investigated by means of optical microscopy, cultivation, single-cell PCR, and 16S... 相似文献
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Libusha Kelly Ursula Pieper Narayanan Eswar Franklin A. Hays Min Li Zygy Roe-Zurz Deanna L. Kroetz Kathleen M. Giacomini Robert M. Stroud Andrej Sali 《Journal of structural and functional genomics》2009,10(4):269-280
Membrane proteins serve as cellular gatekeepers, regulators, and sensors. Prior studies have explored the functional breadth
and evolution of proteins and families of particular interest, such as the diversity of transport-associated membrane protein
families in prokaryotes and eukaryotes, the composition of integral membrane proteins, and family classification of all human
G-protein coupled receptors. However, a comprehensive analysis of the content and evolutionary associations between membrane
proteins and families in a diverse set of genomes is lacking. Here, a membrane protein annotation pipeline was developed to
define the integral membrane genome and associations between 21,379 proteins from 34 genomes; most, but not all of these proteins
belong to 598 defined families. The pipeline was used to provide target input for a structural genomics project that successfully
cloned, expressed, and purified 61 of our first 96 selected targets in yeast. Furthermore, the methodology was applied (1)
to explore the evolutionary history of the substrate-binding transmembrane domains of the human ABC transporter superfamily,
(2) to identify the multidrug resistance-associated membrane proteins in whole genomes, and (3) to identify putative new membrane
protein families. 相似文献
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Nadja Kabelitz Jirina Machackova Gwenaël Imfeld Maria Brennerova Dietmar H. Pieper Hermann J. Heipieper Howard Junca 《Applied microbiology and biotechnology》2009,82(3):565-577
In order to obtain insights in complexity shifts taking place in natural microbial communities under strong selective pressure,
soils from a former air force base in the Czech Republic, highly contaminated with jet fuel and at different stages of a bioremediation
air sparging treatment, were analyzed. By tracking phospholipid fatty acids and 16S rRNA genes, a detailed monitoring of the
changes in quantities and composition of the microbial communities developed at different stages of the bioventing treatment
progress was performed. Depending on the length of the air sparging treatment that led to a significant reduction in the contamination
level, we observed a clear shift in the soil microbial community being dominated by Pseudomonads under the harsh conditions
of high aromatic contamination to a status of low aromatic concentrations, increased biomass content, and a complex composition
with diverse bacterial taxonomical branches.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
The online version of an erratum to this article can be found at http://dx.doi.org/.
An erratum to this article can be found at 相似文献
9.
Macarena Marín Dirk W. Heinz Dietmar H. Pieper Bj?rn U. Klink 《The Journal of biological chemistry》2009,284(47):32709-32716
When methyl-substituted aromatic compounds are degraded via ortho (intradiol)-cleavage of 4-methylcatechol, the dead-end metabolite 4-methylmuconolactone (4-ML) is formed. Degradation of 4-ML has only been described in few bacterial species, including Pseudomonas reinekei MT1. The isomerization of 4-ML to 3-methylmuconolactone (3-ML) is the first step required for the mineralization of 4-ML and is catalyzed by an enzyme termed 4-methylmuconolactone methylisomerase (MLMI). We identified the gene encoding MLMI in P. reinekei MT1 and solved the crystal structures of MLMI in complex with 3-ML at 1.4-Å resolution, with 4-ML at 1.9-Å resolution and with a MES buffer molecule at 1.45-Å resolution. MLMI exhibits a ferredoxin-like fold and assembles as a tight functional homodimeric complex. We were able to assign the active site clefts of MLMI from P. reinekei MT1 and of the homologous MLMI from Cupriavidus necator JMP134, which has previously been crystallized in a structural genomics project. Kinetic and structural analysis of wild-type MLMI and variants created by site-directed mutagenesis indicate Tyr-39 and His-26 to be the most probable catalytic residues. The previously proposed involvement of Cys-67 in covalent catalysis can now be excluded. Residue His-52 was found to be important for substrate affinity, with only marginal effect on catalytic activity. Based on these results, a novel catalytic mechanism for the isomerization of 4-ML to 3-ML by MLMI, involving a bislactonic intermediate, is proposed. This broadens the knowledge about the diverse group of proteins exhibiting a ferredoxin-like fold. 相似文献
10.
Chlorophenol Hydroxylases Encoded by Plasmid pJP4 Differentially Contribute to Chlorophenoxyacetic Acid Degradation 总被引:1,自引:0,他引:1 下载免费PDF全文
Phenoxyalkanoic compounds are used worldwide as herbicides. Cupriavidus necator JMP134(pJP4) catabolizes 2,4-dichlorophenoxyacetate (2,4-D) and 4-chloro-2-methylphenoxyacetate (MCPA), using tfd functions carried on plasmid pJP4. TfdA cleaves the ether bonds of these herbicides to produce 2,4-dichlorophenol (2,4-DCP) and 4-chloro-2-methylphenol (MCP), respectively. These intermediates can be degraded by two chlorophenol hydroxylases encoded by the tfdBI and tfdBII genes to produce the respective chlorocatechols. We studied the specific contribution of each of the TfdB enzymes to the 2,4-D/MCPA degradation pathway. To accomplish this, the tfdBI and tfdBII genes were independently inactivated, and growth on each chlorophenoxyacetate and total chlorophenol hydroxylase activity were measured for the mutant strains. The phenotype of these mutants shows that both TfdB enzymes are used for growth on 2,4-D or MCPA but that TfdBI contributes to a significantly higher extent than TfdBII. Both enzymes showed similar specificity profiles, with 2,4-DCP, MCP, and 4-chlorophenol being the best substrates. An accumulation of chlorophenol was found to inhibit chlorophenoxyacetate degradation, and inactivation of the tfdB genes enhanced the toxic effect of 2,4-DCP on C. necator cells. Furthermore, increased chlorophenol production by overexpression of TfdA also had a negative effect on 2,4-D degradation by C. necator JMP134 and by a different host, Burkholderia xenovorans LB400, harboring plasmid pJP4. The results of this work indicate that codification and expression of the two tfdB genes in pJP4 are important to avoid toxic accumulations of chlorophenols during phenoxyacetic acid degradation and that a balance between chlorophenol-producing and chlorophenol-consuming reactions is necessary for growth on these compounds. 相似文献