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Isolation and Characterization of Pregnancy-Related Proteins
Published in Gábor N. Than, Hans Bohn, Dénes G. Szabó, Advances in Pregnancy-Related Protein Research, 2020
The sedimentation coefficient was determined in double-sector cells using the UV scanner technique at 280 nm in an analytical ultracentrifuge supplied by Beckman (Spinco apparatus, model E) at 60,000 rpm. The solvent used was a 0.05 M phosphate buffer pH 6.8 which contained 0.2 mol/1 NaCl. The protein concentration was adjusted to an optical density of about 3. The sedimentation coefficient was converted to the basis of water at 20°C.
Disease Prediction and Drug Development
Published in Arvind Kumar Bansal, Javed Iqbal Khan, S. Kaisar Alam, Introduction to Computational Health Informatics, 2019
Arvind Kumar Bansal, Javed Iqbal Khan, S. Kaisar Alam
In eukaryotes, a ribosome comprises two ribosomal units: 60S and 40S. Each ribosomal component contains multiple proteins involved in mRNA-translation. The 40S unit comprises 18S rRNA (1900 nucleotides) and 33 proteins, and 60S subunit comprises 5S rRNA (160 nucleotides), 28S rRNA (4700 nucleotides), 5.8S rRNA (160 nucleotides) and 46 proteins. The symbol “S” stands for the Svedberg sedimentation coefficient – a measure on the size of a particle. Many tRNAs are attached by a ribosome concurrently during a translation.
Steroid Hormones, Hormone Secretion, and Steroid Receptors in Carcinogenesis
Published in Velibor Krsmanović, James F. Whitfield, Malignant Cell Secretion, 2019
Radmila Djordjević-Marković, Dušan T. Kanazir
Sucrose-gradient centrifugation indicated that the glucocorticoid-receptor complex has a 10.4-S value under hypotonic conditions and in the presence of Na-molybdate. After Na-molybdate removal and subsequent thermal activation, there was a transition of the 10.4-S form of the rat liver glucocorticoid-receptor complex into 3.7- to 4-S forms.48 This shift in sedimentation coefficient from higher (8 to 10 S) to lower (4S) values is accompanied by the activation of the receptor.21,39,42,43,48
Measuring aggregates, self-association, and weak interactions in concentrated therapeutic antibody solutions
Published in mAbs, 2020
Sumit K. Chaturvedi, Arun Parupudi, Kristian Juul-Madsen, Ai Nguyen, Thomas Vorup-Jensen, Sonia Dragulin-Otto, Huaying Zhao, Reza Esfandiary, Peter Schuck
As an example for the sedimentation behavior exhibited by different mAbs at high concentration, Figure 2 contrasts the sedimentation patterns at 45,000 rpm of mAb A at 37 mg/mL (Figure 2(a)) with those of mAb D at 46 mg/mL (Figure 2(b)). We have already pointed out above the sloping plateaus of mAb A reflecting populations of faster sedimenting oligomeric species (Figure 1(a)). By contrast, mAb D shows a substantially different behavior with much stronger oligomerization, as may be discerned visually from the multi-modal boundary pattern reflecting significant populations of faster-sedimenting oligomers (Figure 2(b)). This is borne out in the corresponding sedimentation coefficient distributions shown in (Figure 3(a,d), respectively). At this point of inspecting the sedimentation patterns and their modeling, it is important to note again that exquisite fits with rmsd of a small fraction of 1% of the loading signal can be achieved to all data. This supports both the validity of the mean-field approximation of nonideality underlying the cNI(s0) model, as well as the detailed interpretation of the resulting sedimentation coefficient distributions (below). The remaining residuals stem from systematic errors rather than stochastic noise, as a result of the very large loading signal.
Analytical characterization of coformulated antibodies as combination therapy
Published in mAbs, 2020
Jun Kim, Yoen Joo Kim, Mingyan Cao, Niluka De Mel, Kenneth Miller, Jared S. Bee, Jihong Wang, Xiangyang Wang, Methal Albarghouthi
AUC sedimentation velocity was used to measure purity, fragmentation, and aggregation. Species with different sizes were separated on the basis of their sedimentation behavior under a strong centrifugal field. Samples and reference buffer were loaded into 12-mm double-sector cells with Epon centerpieces and sapphire windows, placed into an An50-Ti rotor, and installed into a ProteomeLab XL-I centrifuge set to 20°C (Beckman Coulter, Brea, CA). A rotor speed of 42,000 rpm was used to collect UV scans at 280 nm at a radial resolution of 0.002 cm over a range of 5.9–7.2 cm. Reversible self-association of proteins results in a characteristic shift to higher values in the weight-average sedimentation coefficient distribution as the concentration is increased.15 In a similar manner, new peaks representing complexes can be detected by AUC as a function of concentration and ratio of proteins if they interact to form associated species. The SEDFIT software program (National Institutes of Health, Bethesda, MD) was used to generate ls-g*(s) profiles, from which the concentration dependence of the weight-average apparent sedimentation coefficient was determined.
In the quest for new targets for pathogen eradication: the adenylosuccinate synthetase from the bacterium Helicobacter pylori
Published in Journal of Enzyme Inhibition and Medicinal Chemistry, 2018
Ante Bubić, Natalia Mrnjavac, Igor Stuparević, Marta Łyczek, Beata Wielgus-Kutrowska, Agnieszka Bzowska, Marija Luić, Ivana Leščić Ašler
Radial scans of the absorption and interference profiles in the cell were measured at 5- or 7-min intervals on the same protein samples. Analysis of the ultracentrifugation data was done by the Sedfit programme using the continuous c(S) distribution model (www.analyticalultracentrifugation.com/)30. Both the sedimentation coefficient s and the standard sedimentation coefficient s20,w were calculated, and based on them the molecular mass of the species present in the solution was determined, assuming that they have the same friction ratio (also obtained as a parameter in the Sedfit programme). Results shown in the text and in the Tables 1 and 2 are arithmetic means with standard error.