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681.
Esra Ersoy Omeroglu Dılhun Keriman Arserim-Uçar Zeynep Yegin Nevzat Çağlayan Mediha Nur Zafer Yurt Behiye Busra Tasbasi Elif Esma Acar Samet Ucak Veli Cengiz Ozalp Mert Sudagidan 《化学与生物多样性》2023,20(3):e202201182
Propolis is a natural resinous mixture produced by the excretions of honeybees. PCR amplification of the 16S rRNA gene region was achieved using DNA of pre-enriched propolis samples collected from Apis mellifera production hives (n=37) in Eastern Türkiye (Bingöl and its regions). Next-generation sequencing and metabarcoding techniques were used to identify bacterial communities in propolis samples. Firmicutes dominated the phylum structure, with Proteobacteria, Actinobacteria, Tenericutes, and Spirochaetes following. The top three bacterial families were Bacillaceae, Enterobacteriaceae, and Enterococcaceae. Bacillus (dominantly B. badius and B. thermolactis at the species level) was recognized at the genus level, followed by Enterococcus and Clostridium sensu stricto. Our study comprehensively identified the bacterial diversity of propolis samples. Further investigations targeting to enlighten the microbiota of propolis and its potential application fields are required to gain better insight into ecological, nutritional, and medicinal perspectives. 相似文献
682.
Andrzej Furman Emrah Çoraman Yalin E. Çelik Tomasz Postawa Justyna Bachanek Manuel Ruedi 《Zoologica scripta》2014,43(6):549-561
We used both highly variable mitochondrial and nuclear loci to investigate the large mouse‐eared bat species complex in the Western Palaearctic to clarify their systematic position. Although mitochondrial lineages show no species segregation and some haplotypes are shared between Myotis myotis and Myotis blythii sensu lato, Bayesian clustering methods based on multilocus genotypes indicate highly concordant nuclear and morphological species assignment. These multilocus, nuclear analyses detected only a single putative F1 hybrid in the extensive areas of sympatry sampled, thus confirming the biological species status of M. myotis and M. blythii s.l. We propose that the strong cytonuclear discordance in these species complex results from a combination of prior spatial isolation of the two species in different glacial refugia, followed by a succession of mitochondrial introgression events that occurred during the eastward and westward expansions of M. myotis and of M. blythii, respectively. The nuclear markers further indicate the presence of a notable genetic discontinuity within M. myotis that broadly separates populations into an eastern and a western component with an overlap zone in the Balkans. This eastern and western discontinuity is also apparent in the mitochondrial lineages with the D haplogroup largely confined to samples found in Thrace and Asia Minor. None of these genetic discontinuities correspond to the distribution of the two commonly recognized M. myotis subspecies (myotis and macrocephalicus). We also show that distinct morphological subspecies within M. blythii (oxygnathus, omari, risorius and lesviacus) in Europe and the near‐East do not correlate with significant evolutionarily units, whether identified by mitochondrial or nuclear data and thus only represent local morphological variants with little taxonomic relevance. 相似文献
683.
FranÇoise S. Axel 《European biophysics journal : EBJ》1976,2(3):181-218
The present status of the spin labeling method as applied to Biophysics is examined. After an outline of the chemical and physical properties of NO radicals, the analysis of linear and non-linear ESR spectra of spin labels and the informations it yields is described.The possibilities of the method are critically discussed in the light of recent experiments. 相似文献
684.
Budding speciation via peripheral isolation: the Psorodonotus venosus (Orthoptera,Tettigoniidae) species group example 下载免费PDF全文
The peripatric or budding species model has remained theoretical until recently. The habitat preference and range pattern of the mountainous Psorodonotus venosus species group, distributed in Anatolia and Caucasus, offered potential to test the predictions of the model. The study aimed to confirm the parameters and to provide evidence for peripatric speciation in a terrestrial group. Fourteen populations representing the total range of the group were studied. Sequences of two mitochondrial fragments including four loci (12S rDNA+tDNAval+16S rDNA and COI) and a nuclear fragment including three loci (ITS1+5.8S rDNA+ITS2) were obtained and used in phylogenetic, time estimation, population genetics and demographic analyses. Additionally, phenotypical data were provided for the group. Phylogenetic analyses supported the monophyly of the PVG and suggested similar intralineage relationships, but did not support the monophyly of each of the species in the group. The molecular chronograms indicated radiation of the group throughout the Pleistocene. Demographic analyses suggested constant population sizes for the populations in the centre of the range but a significant departure from constancy in four peripheral populations. Genetic diversity is significantly reduced in peripheral populations, but not in others. We arrived to following conclusions. The data suggest that P. venosus is the ancestral species and P. rugulosus, P. tendurek and P. hakkari are bud species, as their haplotypes are nested within P. venosus. As expected under the budding speciation model, (i) in contrast to ancestral species, genetic diversity is reduced, and there are signs of departure from constant population size in bud species; (ii) bud species have isolated and restricted ranges, while the ancestral species does not, (iii) the relative ages of ancestral and bud species are the most reliable data to confirm the model, and chronograms of PVG well support this prediction, and (iv) the divergence events in the group co‐occurred with major climatic transformations of the Pleistocene. 相似文献
685.
686.
Reşit Çakmak Başaran Eyüp Boğa Mehmet Erdoğan Ömer Çınar Ercan Çevik Özge 《Russian Journal of Bioorganic Chemistry》2022,48(2):334-344
Russian Journal of Bioorganic Chemistry - In this study, some Schiff bases derived from 4-aminoantipyrine (4-AAP) (VI–X) were synthesized, characterized by elemental analysis (C, H, N) and... 相似文献
687.
Thermodynamic, kinetic and equilibrium studies during the biosorption of Basic blue 41(BB 41) from aqueous solution using Bacillus macerans were carried out with a focus on pH, contact time, temperature, biomass dosage and initial dye concentration. The maximum adsorption capacity was found to be 89.2 mg/g under optimal conditions of pH (10.0) and temperature (25 °C). The biosorption rates obtained were consistent with the pseudo‐second order kinetic models. The equilibrium data were analyzed using linearized forms of Langmuir and Freundlich isotherms, and the Langmuir isotherm was found to provide the best correlation of the experimental data for the biosorption of BB 41. The equilibrium time for the removal of BB 41 by the biomass was attained within 90 min. Thermodynamic parameters such as free energy (<$>\Delta G<$>), enthalpy (<$>\Delta H<$>), and entropy (<$>\Delta S<$>) were also calculated. The results indicate that biosorption is spontaneous and exothermic in nature. The negative value of entropy confirms the decreased randomness at the solid‐liquid interface during the adsorption of BB 41 onto Bacillus macerans. 相似文献
688.
Tatjana Čelik 《Journal of Insect Conservation》2013,17(5):865-876
The oviposition preferences of Leptidea morsei at the western border of its range (SE Slovenia) were studied with the aim of integrating this information into species habitat management recommendations. The characteristics of egg-laying habitat were examined at the landscape, patch, plant and leaf levels. Because sightings of adults in the field were infrequent, intensive searching for previously laid eggs on Lathyrus niger plants was chosen as the survey method. The main oviposition habitats of L. morsei in Slovenia were found to be the forest edges and light stands of thermophilous oak, oak-hornbeam and mesic beech forests (landscape level). The egg-laying sites were L. niger plants growing individually or in small stands, and oriented mostly towards W, SW, and S. The oviposition plants were between 33 and 120 cm high, with those growing in half to full shade preferred. Eggs were deposited singly, mainly on the underside of leaflets of terminal leaves, located mostly on the top quarter of plants irrespective of their height and growth form. The most important factors affecting egg-placement are sun exposure and the size of L. niger stands at ovipositing sites (patch level), leaf exposure on the plant in vertical and horizontal directions (plant level), leaf age and the leaf parts where the risk of leaf and egg desiccation is lower (leaf level). Management strategies for the main egg-laying habitats of the species are proposed. 相似文献
689.
Ömür Çelikbıçak Kadriye Özlem Hamaloğlu Bekir Salih 《Nucleosides, nucleotides & nucleic acids》2020,39(7):1057-1072
AbstractThe aim of this study is to develop a methodology in which Surface Plasmon Resonance (SPR), Ellipsometer (EM) and Matrix-Assisted Laser Desorption/Ionization-Mass Spectrometry (MALDI-MS) will be used together for detection of single-strand oligodeoxynucleotides (ssODNs) targets. A selected target-ssODNs, and its complementary, the probe-ssODNs carrying a -SH end group, a spacer arm (HS-(CH2)6–(T)15, and a non-complementary ssODNs were used. Silicone based stamps with 16 regions were prepared and used for micro-contact printing (µCP) of the probe-ssODNs on the gold coated surfaces homogeneously. A modulator-spacer molecule (6-mercapto-1-hexanol) was co-immobilized to control surface probe density, to orientate the probe-ssODNs, and to eliminate the nonspecific interactions. SPR was used successfully to follow the hybridization of the target-ssODNs with the immobilized probe-ssODNs on the platform surfaces. Complete hybridizations were achieved in 100?min. It was obtained that there was a linear relationship between relative change in delta and target concentration below 1?µm. Using imaging version of ellipsometer (IEM) allowed imaging of the surfaces and supported extra datum for the SPR results. After a very simple dehybridization protocol, MALDI-MS analysis allowed detection of the target-ssODNs hybridized on the sensor/array platforms. 相似文献
690.