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11.
Karolina Pulka Marta Slupska Anna Puszko Maria Misiak Marcin Wilczek Wiktor Kozminski Aleksandra Misicka 《Journal of peptide science》2013,19(7):433-440
The Pictet–Spengler (PS) reaction was performed with various types of substrates: H‐Trp‐OMe and dipeptides with N‐terminal Trp as arylethylamine components and Z‐protected amino aldehydes and peptidoaldehydes as carbonyl components. We found that the C‐terminal part of Trp derivatives did not have any influence on the stereoselectivity of the reaction and the results are the same for simple esters of Trp and dipeptides. On the contrary, the selectivity of the PS reaction with peptidoaldehydes with L configuration of the C‐terminus residue is totally different from that obtained with simple L‐amino aldehydes. It allows us to obtain cis stereoisomers, which cannot be isolated from the reaction with amino aldehydes. But the utility of the peptidoaldehydes as substrates for the PS reaction is reduced by the side formation of enamides which decrease the yield of cyclization. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
12.
Beata S. Lipska Irena Balasz-Chmielewska Lucyna Morzuch Kacper Wasielewski Dominika Vetter Halina Borzecka Dorota Drozdz Agnieszka Firszt-Adamczyk Ewa Gacka Tomasz Jarmolinski Joanna Ksiazek Elzbieta Kuzma-Mroczkowska Mieczyslaw Litwin Anna Medynska Magdalena Silska Maria Szczepanska Marcin Tkaczyk Anna Wasilewska Franz Schaefer Aleksandra Zurowska Janusz Limon 《Journal of applied genetics》2013,54(3):327-333
Hereditary nephrotic syndrome is caused by mutations in a number of different genes, the most common being NPHS2. The aim of the study was to identify the spectrum of NPHS2 mutations in Polish patients with the disease. A total of 141 children with steroid-resistant nephrotic syndrome (SRNS) were enrolled in the study. Mutational analysis included the entire coding sequence and intron boundaries of the NPHS2 gene. Restriction fragment length polymorphism (RFLP) and TaqMan genotyping assay were applied to detect selected NPHS2 sequence variants in 575 population-matched controls. Twenty patients (14 %) had homozygous or compound heterozygous NPHS2 mutations, the most frequent being c.1032delT found in 11 children and p.R138Q found in four patients. Carriers of the c.1032delT allele were exclusively found in the Pomeranian (Kashubian) region, suggesting a founder effect origin. The 14 % NPHS2 gene mutation detection rate is similar to that observed in other populations. The heterogeneity of mutations detected in the studied group confirms the requirement of genetic testing the entire NPHS2 coding sequence in Polish patients, with the exception of Kashubs, who should be initially screened for the c.1032delT deletion. 相似文献
13.
Barbara Stopa Anna Jagusiak Leszek Konieczny Barbara Piekarska Janina Rybarska Grzegorz Zemanek Marcin Król Piotr Piwowar Irena Roterman 《Journal of molecular modeling》2013,19(11):4731-4740
Congo red dye as well as other eagerly self-assembling organic molecules which form rod-like or ribbon-like supramolecular structures in water solutions, appears to represent a new class of protein ligands with possible wide-ranging medical applications. Such molecules associate with proteins as integral clusters and preferentially penetrate into areas of low molecular stability. Abnormal, partly unfolded proteins are the main binding target for such ligands, while well packed molecules are generally inaccessible. Of particular interest is the observation that local susceptibility for binding supramolecular ligands may be promoted in some proteins as a consequence of function-derived structural changes, and that such complexation may alter the activity profile of target proteins. Examples are presented in this paper. 相似文献
14.
Maria Bendz Marcin Skwark Daniel Nilsson Viktor Granholm Susana Cristobal Lukas Käll Arne Elofsson 《Proteomics》2013,13(9):1467-1480
Topology analysis of membrane proteins can be obtained by enzymatic shaving in combination with MS identification of peptides. Ideally, such analysis could provide quite detailed information about the membrane spanning regions. Here, we examine the ability of some shaving enzymes to provide large‐scale analysis of membrane proteome topologies. To compare different shaving enzymes, we first analyzed the detected peptides from two over‐expressed proteins. Second, we analyzed the peptides from non‐over‐expressed Escherichia coli membrane proteins with known structure to evaluate the shaving methods. Finally, the identified peptides were used to test the accuracy of a number of topology predictors. At the end we suggest that the usage of thermolysin, an enzyme working at the natural pH of the cell for membrane shaving, is superior because: (i) we detect a similar number of peptides and proteins using thermolysin and trypsin; (ii) thermolysin shaving can be run at a natural pH and (iii) the incubation time is quite short. (iv) Fewer detected peptides from thermolysin shaving originate from the transmembrane regions. Using thermolysin shaving we can also provide a clear separation between the best and the less accurate topology predictors, indicating that using data from shaving can provide valuable information when developing new topology predictors. 相似文献
15.
In the case of melanoma, advances in therapies are slow, which raises the need to evaluate new therapeutic strategies and natural products with potential cancer cell inhibiting effect. Pseudofactin II (PFII), a novel cyclic lipopeptide biosurfactant has been isolated from the Arctic strain of Pseudomonas fluorescens BD5. The aim of this study was to investigate the effect of PFII on A375 melanoma cells compared with the effect of PFII on Normal Human Dermis Fibroblast (NHDF) cells and elucidate the underlying mechanism of PFII cytotoxic activity. Melanoma A375 cells and NHDF cells were exposed to PFII or staurosporine and apoptotic death was assessed by monitoring caspase 3-like activity and DNA fragmentation. From time-dependent monitoring of lactate dehydrogenase (LDH) release, Ca2+ influx, and a correlation between Critical Micelle Concentration (CMC) we concluded that cell death is the consequence of plasma membrane permeabilisation by micelles. This finding suggests that pro-apoptotic mechanism of PFII is different from previously described cyclic lipopeptides. The mechanism of PFII specificity towards malignant cells remains to be discovered. The results of this study show that PFII could be a new promising anti-melanoma agent. 相似文献
16.
Izabela Chojnicka Krzysztof Gajos Katarzyna Strawa Gra?yna Broda Sylwia Fudalej Marcin Fudalej Piotr Stawiński Aleksandra Pawlak Pawe? Krajewski Marcin Wojnar Rafa? P?oski 《PloS one》2013,8(2)
Background
rs6943555 in AUTS2 has been shown to modulate ethanol consumption. We hypothesized that rs6943555 might be associated with completed suicide.Methods
We genotyped rs6943555 in 625 completed suicides and 3861 controls using real-time TaqMan Allelic Discrimination Assay. All individuals were Polish Caucasians.Results
We detected an association between suicide and rs6943555 A allele (OR = 1.17, P = 0.018 for allelic comparison, OR = 1.24, P = 0.013 for dominant, and OR = 1.18, P = 0.020 for co-dominant model of inheritance). The association remained significant after adjusting for age and gender (co-dominant: P = 0.002 and dominant model: P = 0.001). After stratifying suicides according to blood ethanol concentration (BAC≤ 20 mg/dl and BAC > 20 mg/dl) the association remained significant only for cases who committed suicide under influence of alcohol (co-dominant: OR = 1.37, P = 0.004 and dominant model: OR = 1.45, P = 0.006). To validate this finding we genotyped another cohort of 132 cases. We reproduced the association between rs6943555 A allele and suicide under influence of ethanol (allelic comparison: OR = 1.55, P = 0.023; co-dominant : OR = 1.54, P = 0.031; dominant model: OR = 1.84, P = 0.015). Analyzing pooled suicides with BAC >20 mg/dl (N = 300) we found the association of rs6943555 A allele not only vs. controls (allelic OR = 1.41, P = 0.00029) but also vs. cases with BAC ≤ 20 mg/dl (N = 449, allelic OR = 1.33, P = 0.019).Conclusions
In our study rs6943555 A allele is associated with suicide committed after drinking ethanol shortly before death. The rs6943555 A allele may be linked to adverse emotional reaction to ethanol, which could explain the association with lower consumption in general population as well as the predisposition to suicide under influence of ethanol. 相似文献17.
Patryk Czortek Anna Delimat Marcin K. Dyderski Antoni Zięba Andrzej M. Jagodziński Bogdan Jaroszewicz 《Nordic Journal of Botany》2020,38(5)
The ability for vegetative growth and development of generative organs often reflects an adaptation to the environment and may be a suitable proxy for understanding population dynamics of rare relict species. An example of such a plant is Carex lachenalii Schkuhr, an arctic-alpine species, in the temperate zone of Europe only occurring in isolated localities of high-elevation mountain ranges. We aimed to assess whether there were relationships between flower production and clonal growth of C. lachenalii, both at the tuft and plot level, and how co-occurring vegetation could modify this relationship. In the study we focused on population-level traits of C. lachenalii, vegetation traits and components of functional diversity. At the tuft level we found that the proportion of flowering ramets of C. lachenalii decreased with increasing diameter of the tuft. At the plot level, in snowbed vegetation C. lachenalii produced more flowering ramets. We suggest this is due to higher environmental stress, expressed by high importance of habitat filtering (low functional dispersion) in shaping species composition of co-occurring vegetation. In granite grasslands and milder environment (expressed by higher functional dispersion), C. lachenalii produced more vegetative ramets, which we suggest is a result of a more competitive environment. While in snowbeds investment in flowering ramets could promote successful persistence of C. lachenalii, survival of subpopulations occurring in the highly competitive conditions of granite grasslands may be uncertain due to potentially weak adaptation to competition with graminoids and dwarf shrubs. 相似文献
18.
Mucha Joanna Zadworny Marcin Helmisaari Heljä-Sisko Nihlgård Bengt Repo Tapani Żytkowiak Maciej Małek Stanisław Reich Peter B. Oleksyn Jacek 《Plant and Soil》2020,455(1-2):507-518
Plant and Soil - Any grouping of tree species concerned with SOC sequestration should include trees that are as homogeneous as possible in their carbon sequestration. We propose a classification of... 相似文献
19.
Ewelina Węglarz-Tomczak Marcin Poręba Anna Byzia Łukasz Berlicki Bogusław Nocek Rory Mulligan Andrzej Joachimiak Marcin Drąg Artur Mucha 《Biochimie》2013
Neisseria meningitides is a gram-negative diplococcus bacterium and is the main causative agent of meningitis and other meningococcal diseases. Alanine aminopeptidase from N. meningitides (NmAPN) belongs to the family of metallo-exopeptidase enzymes, which catalyze the removal of amino acids from the N-terminus of peptides and proteins, and are found among all the kingdoms of life. NmAPN is suggested to be mostly responsible for proteolysis and nutrition delivery, similar to the orthologs from other bacteria. 相似文献
20.
The objective of this study was to assess the effect of an elevated atmospheric CO2 molar ratio on freezing tolerance, photosynthetic apparatus performance and expression of CBF6, Cor14b and LOS2 in meadow fescue (Festuca pratensis Huds.). It was shown that cold acclimation under a CO2 molar ratio of 800 μmol mol(air)?1 decreased the freezing tolerance of meadow fescue when compared to the ambient CO2 level. This effect was not related either to changes observed in PSII redox state or to photosynthetic acclimation to cold, which was in fact more effective at an elevated CO2 level. The decrease in freezing tolerance was linked to changes in the expression of CBF6 and LOS2 genes, whereas the protective effect on photosynthetic apparatus was connected with the activation of a non-photochemical mechanism of photoprotection as well as upregulation of FpCOR14b expression. 相似文献