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71.
Kałużna Monika Albuquerque Pedro Tavares Fernando Sobiczewski Piotr Puławska Joanna 《Applied microbiology and biotechnology》2017,101(2):903-903
Applied Microbiology and Biotechnology - 相似文献
72.
The intermolecular interaction energies in central guanine triad of telomeric B-DNA were estimated based on ab initio quantum
chemistry calculations on the MP2/aDZ level of theory. The source of structural information was molecular dynamics simulation
of both canonical (AGGGTT) and oxidized (AG8oxoGGTT) telomere units. Our calculations demonstrate that significant stiffness
of central triad occurs if 8oxoG is present. The origin of such feature is mainly due to the increase of stacking interactions
of 8oxoG with neighbouring guanine molecules and stronger hydrogen bonding formation of 8oxoG with cytosine if compared with
canonical guanine. Another interesting observation is the context independence of stacking interactions of 8oxoG. Unlike to
5′-G2/G3-3′ and 5′-G3/G4-3′ sequences which are energetically different, 5′-G2/8oxoG3-3′ and 5′-8oxoG3/G4-3′ sequences are almost iso-energetic. 相似文献
73.
Beresewicz M 《Postepy biochemii》2007,53(2):188-197
The postsynaptic density (PSD) is a dynamic multi-protein complex attached to the postsynaptic membrane composed of several hundred proteins such as receptors and channels, scaffolding and adaptor proteins, cell-adhesion proteins, cytoskeletal proteins, G-proteins and their modulators and signaling molecules including kinases and phosphtases. This review focuses on the prominent PSD scaffolds proteins such as members of the MAGUK (membrane-associated guanylyl kinase), Shank (SH3 domain and ankyrin repeat-containing protein) and Homer families. These molecules interact simultaneously with different kinds of receptors and modulate their function by linking the receptors to downstream signaling events. For example PSD 95, a main member of MAGUK family, interacts directly with carboxyl termini of NMDA receptor subunits and clusters them to the postsynaptic membrane. In addition, PSD 95 is involved in binding and organizing proteins connected with NMDAR signaling. Based on the modular character and ability to form multiproteins interactions, MAGUK, Shank and Homer are perfectly suited to act as a major scaffold in postsynaptic density. 相似文献
74.
Wojciech Szczepanik Artur Krężel Magdalena Brzezowska Ewa Dworniczek Małgorzata Jeżowska-Bojczuk 《Inorganica chimica acta》2008,361(9-10):2659-2666
The formation of copper(II) complexes of an aminoglycoside antibiotic – sisomicin – was studied by potentiometry and spectroscopic techniques (UV–Vis, CD, NMR and EPR). At physiological pH, Cu(II) is bound to both amino functions and hydroxyl oxygen of the 2-deoxystreptamine moiety. When pH increases slightly, another amino group located at the aminosugar ring becomes engaged in the coordination process. Microbiological studies with the use of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa showed that copper(II) does not interfere with the bactericidal action of sisomicin. 相似文献
75.
High Quality Independent From a Donor: Human Amniotic Fluid Derived Stem Cells—A Practical Analysis Based on 165 Clinical Cases 下载免费PDF全文
76.
Jagielski AK Podszywałow-Bartnicka P Derlacz RA Bryła J 《Archives of biochemistry and biophysics》2005,434(2):282-288
Effects of various cAMP analogues on gluconeogenesis in isolated rabbit kidney tubules have been investigated. In contrast to N(6),2'-O-dibutyryladenosine-3',5'-cyclic monophosphate (db-cAMP) and cAMP, which accelerate renal gluconeogenesis, 8-bromoadenosine-3',5'-cyclic monophosphate (Br-cAMP) and 8-(4-chlorophenylthio)-cAMP (pCPT-cAMP) inhibit glucose production. Stimulatory action of cAMP and db-cAMP may be evoked by butyrate and purinergic agonists generated during their extracellular and intracellular metabolism resulting in an increase in flux through fructose-1,6-bisphosphatase and in consequence acceleration of the rate of glucose formation. On the contrary, Br-cAMP is poorly metabolized in renal tubules and induces a fall of flux through glyceraldehyde-3-phosphate dehydrogenase. The contribution of putative extracellular cAMP receptors to the inhibitory Br-cAMP action is doubtful in view of a decline of glucose formation in renal tubules grown in the primary culture supplemented with forskolin. The presented data indicate that in contrast to hepatocytes, in kidney-cortex tubules an increased intracellular cAMP level results in an inhibition of glucose production. 相似文献
77.
78.
A proline iminopeptidase (EC. 3.4.11.5) was isolated from shoots of 3 day old seedlings. The purification procedure consisted
of 5 steps: acid precipitation, gel filtration on Sephadex G-200, ion-exchange chromatography on Sepharose CL 6B, twice repeated
hydrophoic chromatography on Phenyl-Sepharose HP. The enzyme was purified 404.8-fold, with the specific activity of 8.5 units
mg−1 of protein with recovery yield of 3%. The purified enzyme had a molecular mass of 225 kDa estimated by gel filtration and
55.4 kDa by SDS PAGE. This indicates that native enzyme is composed of four subunits. The enzyme was specific for proline
β-naphtylamide among various amino acid β-naphtylamides.
An optimal activity was observed at 37 °C at pH 7.75. The enzyme was thermostable up to 37 °C for 30 min. The enzyme was strongly
inhibited by pHMB, E-64, heavy metal ions and partially by PMSF, DFP. The results suggest that cysteine and serine residues
may participate in the enzyme activity. 相似文献
79.
80.
tRNA residues that have coevolved with their anticodon to ensure uniform and accurate codon recognition 总被引:3,自引:0,他引:3
The structure, phylogeny and in vivo function of the base pair formed between nucleotides 32 and 38 of the tRNA anticodon loop are reviewed. The A32-U38 pair, which is highly conserved in tRNA2(Ala) and sometimes observed in tRNA2(Pro), was recently found to decrease the affinity of tRNAs to the ribosomal A site relative to other 32-38 combinations. This suggests that the role of 32-38 pair is to tune the tRNA affinity in the A site to a uniform value. New experiments presented here show that the U32C mutation in tRNA1(Gly) increases its affinity to the cognate codon and to codons with third position mismatches in the A site. This suggests that one reason for uniform tRNA binding to evolve was to avoid incorrect codon recognition. 相似文献