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91.
Flax zygotic embryogenesis was studied for isozyme patterns of acid phosphatase and esterase and for content of total proteins.
For acid phosphatase, six multiple molecular forms or isozymes, were identified during flax zygotic embryo development. For
esterase, six isozymes were expressed during zygotic flax embryogenesis. Some of the isozymes were expressed during entire
embryogenesis, and some were only transiently expressed or appeared near maturation. The amount of total proteins was very
low at early embryogenesis and proteins in a range from 26.6 kDa to 97.4 kDa were expressed. During further flax embryo development
the protein spectra became more diverse and the quantity of total proteins increased. Proteins ranging from 3.4 kDa to 97.4
kDa were present, and proteins of 20 kDa to 36.5 kDa were expressed in the highest amount. The results are discussed with
reference to selected information in the literature.
Received: 16 October 2000 / Revision accepted: 20 April 2001 相似文献
92.
Hála M Cole R Synek L Drdová E Pecenková T Nordheim A Lamkemeyer T Madlung J Hochholdinger F Fowler JE Zárský V 《The Plant cell》2008,20(5):1330-1345
The exocyst, an octameric tethering complex and effector of Rho and Rab GTPases, facilitates polarized secretion in yeast and animals. Recent evidence implicates three plant homologs of exocyst subunits (SEC3, SEC8, and EXO70A1) in plant cell morphogenesis. Here, we provide genetic, cell biological, and biochemical evidence that these and other predicted subunits function together in vivo in Arabidopsis thaliana. Double mutants in exocyst subunits (sec5 exo70A1 and sec8 exo70A1) show a synergistic defect in etiolated hypocotyl elongation. Mutants in exocyst subunits SEC5, SEC6, SEC8, and SEC15a show defective pollen germination and pollen tube growth phenotypes. Using antibodies directed against SEC6, SEC8, and EXO70A1, we demonstrate colocalization of these proteins at the apex of growing tobacco pollen tubes. The SEC3, SEC5, SEC6, SEC8, SEC10, SEC15a, and EXO70 subunits copurify in a high molecular mass fraction of 900 kD after chromatographic fractionation of an Arabidopsis cell suspension extract. Blue native electrophoresis confirmed the presence of SEC3, SEC6, SEC8, and EXO70 in high molecular mass complexes. Finally, use of the yeast two-hybrid system revealed interaction of Arabidopsis SEC3a with EXO70A1, SEC10 with SEC15b, and SEC6 with SEC8. We conclude that the exocyst functions as a complex in plant cells, where it plays important roles in morphogenesis. 相似文献
93.
Mistiniene E Pozdniakovaite N Popendikyte V Naktinis V 《International journal of biological macromolecules》2005,37(1-2):61-68
Seventeen mutants with one, two or three amino acids substitutions of human protein p14.5, homologue to well-known tumor antigen from goat liver UK114 and a member of proteins YER057c/YIL051c/YjgF family, have been used for structure-functional relation studies and ligand binding analysis using cross-linking by triacryloyl-hexahydro-s-triazine (TAT), size exclusion chromatography, free fatty acid and 8-anilino-1-naphthalenesulfonic acid (ANS) binding assays. Amino acids having the most significant impact on the ligand binding activity have been determined: R107, N93, Y21 and F89. Arginine 107 has been identified as the most accessible amino acid in the cleft. Trimeric structure of protein p14.5 has been confirmed as being essential for stoichiometric small ligand binding activity and oligomeric structure of p14. Ligand binding activity may be related with the biological functions of these proteins, which still are not understood well. 相似文献
94.
Katerina Demnerová Martina Mackova Veronika Spevákova Katarina Beranova Lucie Kochánková Petra Lovecká Edita Ryslavá Tomas Macek 《International microbiology》2005,8(3):205-211
As part of the EU project MULTIBARRIERS, six new endogenous aerobic bacterial isolates able to grow in the presence of BTmX (benzene, toluene, m-xylene) were characterized with respect to their growth specificities. Preliminary analysis included restriction fragment length polymorphism profiles and 16S rDNA sequencing. The diversity of these strains was confirmed by denaturing gradient gel electrophoresis. Additional aerobic bacterial strains were isolated from the rhizospheres of plants grown in polychlorinated biphenyl (PCB)-contaminated soils. Pot experiments were designed to show the beneficial effect of plants on the bacterial degradation of PCBs. The effect of PCB removal from soil was evaluated and bacteria isolated from three different plant species were examined for the presence of the bph operon. 相似文献
95.
Edita Čapkauskaitė Asta Zubrienė Alexey Smirnov Jolanta Torresan Miglė Kišonaitė Justina Kazokaitė Joana Gylytė Vilma Michailovienė Vaida Jogaitė Elena Manakova Saulius Gražulis Sigitas Tumkevičius Daumantas Matulis 《Bioorganic & medicinal chemistry》2013,21(22):6937-6947
Two groups of benzenesulfonamide derivatives, bearing pyrimidine moieties, were designed and synthesized as inhibitors of carbonic anhydrases (CA). Their binding affinities to six recombinant human CA isoforms I, II, VI, VII, XII, and XIII were determined by the thermal shift assay (TSA). The binding of several inhibitors was measured by isothermal titration calorimetry (ITC). Direct demonstration of compound inhibition was achieved by determining the inhibition constant by stopped-flow CO2 hydration assay. The most potent compounds demonstrated selectivity towards isoform I and affinities of 0.5 nM. The crystal structures of selected compounds in complex with CA II, XII, and XIII were determined to atomic resolution. Compounds described here were compared with previously published pyrimidinebenzenesulfonamides.1 Systematic structure–activity analysis of 40 compound interactions with six isoforms yields clues for the design of compounds with greater affinities and selectivities towards target CA isoforms. 相似文献
96.
Milda Pleckaityte Lina Mistinaite Edita Mistiniene Gervydas Dienys Gintas Zvirblis 《Biocatalysis and Biotransformation》2013,31(3-4):191-200
The guanidine-hydrochloride (Gdn-HCl) and thermally induced unfolding of Hsp70 from Meiothermus ruber (Mru.Hsp70) were analysed using tryptophan fluorescence and 8-anilino-1-naphthalenesulfonic acid (ANS) binding. The ANS binding to Mru.Hsp70 showed both the increase in fluorescence intensity and a shift in emission maximum. Analysis of the unfolding profile of Mru.Hsp70 indicated that Gdn-HCl induced unfolding of Mru.Hsp70 occurred through intermediate species. The tryptophan and ANS fluorescence emission spectra revealed that ATP induced conformational change increased the thermal stability of Mru.Hsp70. The data obtained are similar to those of Escherichia coli DnaK. The ATP-ase activity of chaperones is fundamental for their biological activity. It this paper we demonstrate that, in contrast to Thermus thermophilus, both Mru.Hsp40 and Mru.Hsp22 co-chaperones affect the ATP-ase activity of Mru.Hsp70. The use of truncated Mru.Hsp40 proteins showed that full-length Mru.Hsp40 is required for stimulation of ATP-ase activity of Mru.Hsp70. E. coli GrpE could act as nucleotide exchange factor the in thermophilic Hsp70 ATP hydrolysis reaction. However, the role of E. coli DnaJ in the M. ruber ATP cycle needs further analysis. We selected the new substrate laccA suitable for determination of refolding activity of thermophilic chaperones. 相似文献
97.
Lenka Vojtíšková Edita Munzarová Olga Votrubová Hana Čížková Helena Lipavská 《Hydrobiologia》2006,563(1):73-85
Carbon and nitrogen balance in Acorus calamus, a wetland species colonising littoral zones with a high trophic status, was studied under experimental conditions using
water or sand culture with a defined composition of the nutrient solution. Influence of graded level of N (1.86, 7.5 and 18.6
mM) and/or forms of N (NH4+ versus NO 3–) on the content of non-structural carbohydrates, free amino acids, total C, and total N was studied in Acorus rhizomes and roots to find possible connection with a reduced growth of Acorus plants under high N and NH4+–N nutrition described in our previous study [Vojtíšková et al., 2004. Hydrobiologia 518: 9–22]. High N availability and pure
NH4+–N nutrition affected the C/N balance of rhizome and root systems of Acorus in a similar way. NH4+–N was the only form of N elevated under the high N treatment. The major proportion of the total non-structural carbohydrates
(TNC) was starch (91–93% and 51–64% in rhizomes and roots, respectively). The content of starch was significantly and and
negatively affected by high N availability (P = 0.001), as well as by NH4+–N nutrition (P=0.001). Amounts of simple soluble carbohydrates (sucrose, glucose, and fructose) were negligible in comparison to starch
in rhizomes and branched roots (up to 5% of TNC), while roots without developed lateral roots (unbranched) contained up to
33% of TNC in the form of simple soluble sugars. Moreover, high hexoses/sucrose ratio, low starch/soluble sugars ratio, high
content of N, and low C/N ratio support the notion that unbranched roots are metabolically active young roots with tissue
differentiation in progress. A high content of free amino acids, typically with dominance of N-rich amino acids (Arg-46%,
Gln-8%, Asn-7%), was found simultaneously with a low carbohydrate content under high N supply, which indicates that NH4+ received is effectively incorporated into the organic form by this species. Since the decrease in carbohydrate content was
not accompanied by luxurious growth, other possible carbon consuming processes were discussed in relation to NH4+ nutrition. More dramatic changes in total N than C were found under high N availability resulting a shift in C/N ratio in
favour of N. Although the shift towards N metabolism was obvious, no serious carbohydrate depletion occurred, which could
explain the reduced growth of Acorus plants under high N and sole NH4+–N nutrition described previously. 相似文献
98.
Andreas Michal Naďo Ladislav Bendová Barbora Uhrin Marcel Maxinová Edita Lučan Radek Benda Petr 《Acta theriologica》2023,68(2):189-202
Mammal Research - The diet of Rhinolophus euryale was studied in southeastern Slovakia by an analysis of faeces collected from netted bats. Prey availability was studied using light traps, counting... 相似文献
99.
In this study we performed the phylogenetic analysis of non-cultivable bacteria from anthropogenically disturbed soil using partial sequences of the 16S rRNA (16S rDNA) and the heavy-metal resistance genes. This soil sample contained high concentrations of nickel (2,109 mg/kg), cobalt (355 mg/kg) and zinc (177 mg/kg), smaller concentrations of iron (35.75 mg/kg) and copper (32.2 mg/kg), and also a trace amount of cadmium (<0.25 mg/kg). The 16S rDNA sequences from a total of 74 bacterial clones were distributed into four broad taxonomic groups, Acidobacteria, Actinobacteria, Bacteroidetes and Gemmatimonadetes, and some of them were unidentified. Comparing our clone sequences with those from the GenBank database, only 9 clones displayed high similarity to known bacteria belongig to actinomycetes; others were identified as uncultured ones. Among clones evidently Actinobacteria predominated. Sixteen clones from soil sample carried only the nccA-like heavy-metal-resistance genes and all sequences showed too low similarity to known proteins encoded by these genes. However, our results suggested that the heavy-metal-contaminated soil is able to present very important reservoir of the new and until now unknown partly bacteria, partly heavy-metal-resistance determinants and their products. Bacteria and nccA-like genes identified in this study could represent the objects of interest as bioremediation agents because they can be potentially used in different transformation and immobilization processes. 相似文献
100.
Jungeun Won Ryan G. Porter Michael A. Novak Jon Youakim Ada Sum Ronit Barkalifa Edita Aksamitiene Anqi Zhang Ryan Nolan Ryan Shelton Stephen A. Boppart 《Journal of biophotonics》2021,14(4):e202000215
Decreased mobility of the human eardrum, the tympanic membrane (TM), is an essential indicator of a prevalent middle ear infection. The current diagnostic method to assess TM mobility is via pneumatic otoscopy, which provides subjective and qualitative information of subtle motion. In this study, a handheld spectral-domain pneumatic optical coherence tomography system was developed to simultaneously measure the displacement of the TM, air pressure inputs applied to a sealed ear canal, and to perform digital pneumatic otoscopy. A novel approach based on quantitative parameters is presented to characterize spatial and temporal variations of the dynamic TM motion. Furthermore, the TM motions of normal middle ears are compared with those of ears with middle ear infections. The capability of noninvasively measuring the rapid motion of the TM is beneficial to understand the complex dynamics of the human TM, and can ultimately lead to improved diagnosis and management of middle ear infections. 相似文献