Functional Subunits of Eukaryotic Chaperonin CCT/TRiC in Protein Folding

Molecular chaperones are a class of proteins responsible for proper folding of a large number of polypeptides in both prokaryotic and eukaryotic cells. Newly synthesized polypeptides are prone to nonspecific interactions, and many of them make toxic aggregates in absence of chaperones. The eukaryotic chaperonin CCT is a large, multisubunit, cylindrical structure having two identical rings stacked back to back. Each ring is composed of eight different but similar subunits and each subunit has three distinct domains. CCT assists folding of actin, tubulin, and numerous other cellular proteins in an ATP-dependent manner. The catalytic cooperativity of ATP binding/hydrolysis in CCT occurs in a sequential manner different from concerted cooperativity as shown for GroEL. Unlike GroEL, CCT does not have GroES-like cofactor, rather it has a built-in lid structure responsible for closing the central cavity. The CCT complex recognizes its substrates through diverse mechanisms involving hydrophobic or electrostatic interactions. Upstream factors like Hsp70 and Hsp90 also work in a concerted manner to transfer the substrate to CCT. Moreover, prefoldin, phosducin-like proteins, and Bag3 protein interact with CCT and modulate its function for the fine-tuning of protein folding process. Any misregulation of protein folding process leads to the formation of misfolded proteins or toxic aggregates which are linked to multiple pathological disorders

Optimization of absorption/desorption parameters of Brownmillerite SrCoO2.5 for oxygen storage

The order-disorder transition of Brownmillerite (BM)-type oxides have gained attraction for oxygen enrichment applications. Herein, BM SrCoO2.5 is exploited for oxygen storage and separation across its order-disorder transition. Optimized temperature and duration of heat treatment in an oxygen atmosphere for obtaining maximum oxygen storage is explored. A maximum of 15.28 cm(3) of O-2 per gram of the material can be stored in the sample at STP by a heat-treatment at 673-693 K. A drastic increase in ionic conductivity of the sample above a certain temperature gave rise to a threshold temperature for oxygen absorption. Kinetics of oxygen release appeared to follow nucleation and growth model and the rate of desorption was found to increase with rise in temperature. The oxygen intake/release of BM SrCoO2.5 occurs within minutes in a completely reversible manner facilitating a low cost O-2 separation through vacuum swing adsorption

Stabilization of Brownmillerite-Type SrCoO2.5 by a Cost-Effective Quenching Method for Oxygen-Scavenging Applications

Brownmillerite (BM)-type oxide sorbents have gained attention recently for producing oxygen-enriched streams. Herein, a cost-effective method of quenching with the use of an Al foil pad is adapted for the synthesis of brownmillerite SrCoO2.5. The oxygen storage capacity of this oxide has been investigated using a simple home-built volumetric setup. The oxygen-rich phase was formed by a pressurized heat-treatment of a BM sample. The oxygen storage capacity of the sample has been calculated from the pressure change during desorption. The effect of oxygen pressure on the amount of oxygen stored inside the sample has also been evaluated. Furthermore, selective absorption of oxygen is confirmed by performing the absorption in compressed air. The results indicate that 15.28 cm(3) O-2 g(-1) can be stored in the sample at STP. The change in oxygen content in SrCoO2.5+delta varied reversibly up to a delta value of 0.26, which is confirmed by iodometric titration. It is shown that the new method of quenching proposed does not deteriorate the oxygen storage property of the material

Proceedings of International Web Conference in Civil Engineering for a Sustainable Planet

This proceeding contains articles of the various research ideas of the academic community and practitioners accepted at the "International Web Conference in Civil Engineering for a Sustainable Planet (ICCESP 2021)". ICCESP 2021 is being Organized by the Habilete Learning Solutions, Kollam in Collaboration with American Society of Civil Engineers (ASCE), TKM College of Engineering, Kollam, and Baselios Mathews II College of Engineering, Kollam, Kerala, India. Conference Title: International Web Conference in Civil Engineering for a Sustainable PlanetConference Acronym: ICCESP 2021Conference Date: 05–06 March 2021Conference Location: Online (Virtual Mode)Conference Organizer: Habilete Learning Solutions, Kollam, Kerala, IndiaCollaborators: American Society of Civil Engineers (ASCE), TKM College of Engineering, Kollam, and Baselios Mathews II College of Engineering, Kollam, Kerala, India