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1.
Sven Hoefman David van der Ha Nico Boon Peter Vandamme Paul De Vos Kim Heylen 《Antonie van Leeuwenhoek》2014,105(2):353-366
The growth of twelve methanotrophic strains within the genus Methylomonas, including the type strains of Methylomonas methanica and Methylomonas koyamae, was evaluated with 40 different variations of standard diluted nitrate mineral salts medium in 96-well microtiter plates. Unique profiles of growth preference were observed for each strain, showing a strong strain dependency for optimal growth conditions, especially with regards to the preferred concentration and nature of the nitrogen source. Based on the miniaturized screening results, a customized medium was designed for each strain, allowing the improvement of the growth of several strains in a batch setup, either by a reduction of the lag phase or by faster biomass accumulation. As such, the maintenance of fastidious strains could be facilitated while the growth of fast-growing Methylomonas strains could be further improved. Methylomonas sp. R-45378 displayed a 50 % increase in cell dry weight when grown in its customized medium and showed the lowest observed nitrogen and oxygen requirement of all tested strains. We demonstrate that the presented miniaturized approach for medium optimization is a simple tool allowing the quick generation of strain-specific growth preference data that can be applied downstream of an isolation campaign. This approach can also be applied as a first step in the search for strains with biotechnological potential, to facilitate cultivation of fastidious strains or to steer future isolation campaigns. 相似文献
2.
According to the ideomotor theory, actions are represented in terms of their perceptual effects, offering a solution for the correspondence problem of imitation (how to translate the observed action into a corresponding motor output). This effect-based coding of action is assumed to be acquired through action-effect learning. Accordingly, performing an action leads to the integration of the perceptual codes of the action effects with the motor commands that brought them about. While ideomotor theory is invoked to account for imitation, the influence of action-effect learning on imitative behavior remains unexplored. In two experiments, imitative performance was measured in a reaction time task following a phase of action-effect acquisition. During action-effect acquisition, participants freely executed a finger movement (index or little finger lifting), and then observed a similar (compatible learning) or a different (incompatible learning) movement. In Experiment 1, finger movements of left and right hands were presented as action-effects during acquisition. In Experiment 2, only right-hand finger movements were presented during action-effect acquisition and in the imitation task the observed hands were oriented orthogonally to participants’ hands in order to avoid spatial congruency effects. Experiments 1 and 2 showed that imitative performance was improved after compatible learning, compared to incompatible learning. In Experiment 2, although action-effect learning involved perception of finger movements of right hand only, imitative capabilities of right- and left-hand finger movements were equally affected. These results indicate that an observed movement stimulus processed as the effect of an action can later prime execution of that action, confirming the ideomotor approach to imitation. We further discuss these findings in relation to previous studies of action-effect learning and in the framework of current ideomotor approaches to imitation. 相似文献
3.
Thomas Arn Hansen Helena Fridholm Tobias Guldberg Fr?slev Kristín Rós Kjartansdóttir Eske Willerslev Lars Peter Nielsen Anders Johannes Hansen 《PloS one》2015,10(11)
Rattus norvegicus (R. norvegicus) are ubiquitous and their presence has several effects on the human populations in our urban areas on a global scale. Both historically and presently, this close interaction has facilitated the dissemination of many pathogens to humans, making screening for potentially zoonotic and emerging viruses in rats highly relevant. We have investigated faecal samples from R. norvegicus collected from urban areas using a protocol based on metagenomic enrichment of circular DNA genomes and subsequent sequencing. We found a new type of papillomavirus, with a L1 region 82% identical to that of the known R. norvegicus Papillomavirus 2. Additionally, we found 20 different circular replication associated protein (Rep)-encoding single stranded DNA (CRESS-DNA) virus-like genomes, one of which has homology to the replication-associated gene of Beak and feather disease virus. Papillomaviruses are a group of viruses known for their carcinogenic potential, and although they are known to infect several different vertebrates, they are mainly studied and characterised in humans. CRESS-DNA viruses are found in many different environments and tissue types. Both papillomaviruses and CRESS-DNA viruses are known to have pathogenic potential and screening for novel and known viruses in R. norvegicus could help identify viruses with pathogenic potential. 相似文献
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F Albericio R van Abel G Barany 《International journal of peptide and protein research》1990,35(3):284-286
Attempts to anchor Fmoc-asparagine or glutamine as p-alkoxybenzyl esters for solid-phase peptide synthesis are fraught with difficulties. A convenient and effective method to prepare peptides with C-terminal asparagine or glutamine involves quantitative attachment of N alpha-Fmoc-C alpha-tert.-butyl aspartate or glutamate via the free omega-carboxyl groups to a tris(alkoxy)benzylamino (PAL) support. Chain elongation proceeds normally by standard Fmoc chemistry, and treatment with acid, e.g., CF3COOH--CH2Cl2, 90 min at 25 degrees, releases the desired peptides in greater than 95% yields without side reactions at the C-terminus. Feasibility of the approach has been demonstrated by the syntheses of the C-terminal octapeptide from human proinsulin, H-Leu-Ala-Leu-Glu-Gly-Ser-Leu-Gln-OH, and the serum thymic factor pGlu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn-OH. 相似文献
7.
J. H. D. Bassett A. A. J. Pannett S. A. Forbes R. V. Thakker M. McCarthy A. P. Read B. T. Teh C. Larsson S. Kytölä J. Leisti P. Salmela G. Weber S. Giraud C. X. Zhang A. Calender J. W. M. Höppener H. K. Ploos van Amstel C. J. M. Lips K. Kas W. J. M. Van de Ven P. Gaudray 《Human genetics》1997,100(5-6):657-665
Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder characterised by tumours of the parathyroids,
pancreas and anterior pituitary. The MEN1 gene has been localised to a 2-Mb region of chromosome 11q13 by meiotic mapping
studies in MEN1 families. Such studies may have a limited resolution of approximately 1 cM (i.e. 1 Mb) and we have therefore
investigated 96 MEN1 families (40 British, 17 French, 12 Finnish, 7 Swedish, 7 Dutch, 7 North American, 2 Australian, 1 New
Zealand, 1 German, 1 Spanish and 1 Danish) for linkage disequilibrium, in order to facilitate a finer mapping resolution.
We have utilised five microsatellite DNA sequence polymorphisms from the candidate region and have accurately determined their
allele sizes, which ranged from 161 bp to 272 bp. The heterozygosity and number of alleles (given in brackets), respectively,
at the loci were: D11S1883 (76%, 11), D11S457 (55%, 5), PYGM (94%, 18), D11S1783 (10%, 4) and D11S449 (87%, 16). Allelic association
was assessed by Chi-square 2 ×n contingency tables, by Fisher exact 2 ×n contingency tables and by a likelihood-based approach. The results of haplotype analysis revealed 91 different affected haplotypes
in the 96 families, an identical affected haplotype being observed in no more than two families. These results indicate the
absence of an ancestral affected haplotype. Significant linkage disequilibrium (P < 0.005) could be established amongst the microsatellite loci but not between the loci and MEN1 in either the total population
or in any of the geographical sub-populations. The absence of linkage disequilibrium between MEN1 and the polymorphic loci
is probably the result of the occurrence of multiple different disease-causing mutations in MEN1.
Received: 1 April 1997 / Accepted: 25 June 1997 相似文献
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9.
Daw-Yang Hwang Stefan Kohl Xueping Fan Asaf Vivante Stefanie Chan Gabriel C. Dworschak Julian Schulz Albertien M. van Eerde Alina C. Hilger Heon Yung Gee Tracie Pennimpede Bernhard G. Herrmann Glenn van de Hoek Kirsten Y. Renkema Christoph Schell Tobias B. Huber Heiko M. Reutter Neveen A. Soliman Natasa Stajic Radovan Bogdanovic Elijah O. Kehinde Richard P. Lifton Velibor Tasic Weining Lu Friedhelm Hildebrandt 《Human genetics》2015,134(8):905-916
10.