Архетип свобода у контексті французької політичної теорії та історії

Розглянуто сучасні підходи щодо аналізу політичної ментальності. У межах політологічного аналізу окреслено коло проблем, які потребують вирішення з використанням підходів психології. Зроблено висновок про те, що архетип “свобода” становить важливий елемент політичної ментальності французів.Modern approaches of analysis of political mentality are considered. Within the limits of political science analysis outlined circle of problems which need decision with the use of approaches of psychology. A conclusion is done that archetype freedom makes the important element of political mentality of French’s

Two different proteins that compete for binding to thrombin have opposite kinetic and thermodynamic profiles

Thrombin binds thrombomodulin (TM) at anion binding exosite 1, an allosteric site far from the thrombin active site. A monoclonal antibody (mAb) has been isolated that competes with TM for binding to thrombin. Complete binding kinetic and thermodynamic profiles for these two protein–protein interactions have been generated. Binding kinetics were measured by Biacore. Although both interactions have similar KDs, TM binding is rapid and reversible while binding of the mAb is slow and nearly irreversible. The enthalpic contribution to the ΔGbind was measured by isothermal titration calorimetry and van’t Hoff analysis. The contribution to the ΔGbind from electrostatic steering was assessed from the dependence of the ka on ionic strength. Release of solvent H2O molecules from the interface was assessed by monitoring the decrease in amide solvent accessibility at the interface upon protein–protein binding. The mAb binding is enthalpy driven and has a slow kd. TM binding appears to be entropy driven and has a fast ka. The favorable entropy of the thrombin–TM interaction seems to be derived from electrostatic steering and a contribution from solvent release. The two interactions have remarkably different thermodynamic driving forces for competing reactions. The possibility that optimization of binding kinetics for a particular function may be reflected in different thermodynamic driving forces is discussed

Directed mutagenesis alters the stereochemistry of catalysis by isolated ketoreductase domains from the erythromycin polyketide synthase

The ketoreductase (KR) domains eryKR(1) and eryKR(2) from the erythromycin-producing polyketide synthase (PKS) reduce 3-ketoacyl-thioester intermediates with opposite stereospecificity. Modeling of eryKR(1) and eryKR(2) showed that conserved amino acid

Solution structure of the tandem acyl carrier protein domains from a polyunsaturated fatty acid synthase reveals beads-on-a-string configuration.

The polyunsaturated fatty acid (PUFA) synthases from deep-sea bacteria invariably contain multiple acyl carrier protein (ACP) domains in tandem. This conserved tandem arrangement has been implicated in both amplification of fatty acid production (additive effect) and in structural stabilization of the multidomain protein (synergistic effect). While the more accepted model is one in which domains act independently, recent reports suggest that ACP domains may form higher oligomers. Elucidating the three-dimensional structure of tandem arrangements may therefore give important insights into the functional relevance of these structures, and hence guide bioengineering strategies. In an effort to elucidate the three-dimensional structure of tandem repeats from deep-sea anaerobic bacteria, we have expressed and purified a fragment consisting of five tandem ACP domains from the PUFA synthase from Photobacterium profundum. Analysis of the tandem ACP fragment by analytical gel filtration chromatography showed a retention time suggestive of a multimeric protein. However, small angle X-ray scattering (SAXS) revealed that the multi-ACP fragment is an elongated monomer which does not form a globular unit. Stokes radii calculated from atomic monomeric SAXS models were comparable to those measured by analytical gel filtration chromatography, showing that in the gel filtration experiment, the molecular weight was overestimated due to the elongated protein shape. Thermal denaturation monitored by circular dichroism showed that unfolding of the tandem construct was not cooperative, and that the tandem arrangement did not stabilize the protein. Taken together, these data are consistent with an elongated beads-on-a-string arrangement of the tandem ACP domains in PUFA synthases, and speak against synergistic biocatalytic effects promoted by quaternary structuring. Thus, it is possible to envision bioengineering strategies which simply involve the artificial linking of multiple ACP domains for increasing the yield of fatty acids in bacterial cultures

A recombinant gp145 Env glycoprotein from HIV-1 expressed in two different cell lines: Effects on glycosylation and antigenicity.

The envelope glycoprotein (Env) of the human immunodeficiency virus (HIV), has been the primary target for the development of a protective vaccine against infection. The extensive N-linked glycosylation on Env is an important consideration as it may affect efficacy, stability, and expression yields. The expression host has been shown to influence the extent and type of glycosylation that decorates the protein target. Here, we report the glycosylation profile of the candidate subtype C immunogen CO6980v0c22 gp145, which is currently in Phase I clinical trials, produced in two different host cells: CHO-K1 and Expi293F. The amino acid sequence for both glycoproteins was confirmed to be identical by peptide mass fingerprinting. However, the isoelectric point of the proteins differed; 4.5-5.5 and 6.0-7.0 for gp145 produced in CHO-K1 and Expi293F, respectively. These differences in pI were eliminated by enzymatic treatment with sialidase, indicating a large difference in the incorporation of sialic acid between hosts. This dramatic difference in the number of sialylated glycans between hosts was confirmed by analysis of PNGase F-released glycans using MALDI-ToF MS. These differences in glycosylation, however, did not greatly translate into differences in antibody recognition. Biosensor assays showed that gp145 produced in CHO-K1 had similar affinity toward the broadly neutralizing antibodies, 2G12 and PG16, as the gp145 produced in Expi293F. Additionally, both immunogens showed the same reactivity against plasma of HIV-infected patients. Taken together, these results support the notion that there are sizeable differences in the glycosylation of Env depending on the expression host. How these differences translate to vaccine efficacy remains unknown

Multiple sequence alignment of the five ACP domains.

<p>The ACP domains from the <i>Photobacterium profundum</i> PUFA synthase were aligned using ClustalW. The black bars denote the stretches of protein sequence predicted to be α-helices.</p