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Full-Text Articles in Physical Sciences and Mathematics

The Role Of Catalytic Residue PKA On The Hydrolysis/Transglycosylation Partition In Family 3 Β-Glucosidases, Inacrist Geronimo, Christina M. Payne, Mats Sandgren Dec 2017

The Role Of Catalytic Residue PKA On The Hydrolysis/Transglycosylation Partition In Family 3 Β-Glucosidases, Inacrist Geronimo, Christina M. Payne, Mats Sandgren

Chemical and Materials Engineering Faculty Publications

β-Glucosidases (βgls) primarily catalyze the hydrolysis of the terminal glycosidic bond at the non-reducing end of β-glucosides, although glycosidic bond synthesis (called transglycosylation) can also occur in the presence of another acceptor. In the final reaction step, the glucose product or another substrate competes with water for transfer to the glycosyl-enzyme intermediate. The factors governing the balance between the two pathways are not fully known; however, the involvement of ionizable residues in binding and catalysis suggests that their pKa may play a role. Through constant pH molecular dynamics simulations of a glycoside hydrolase Family 3 (GH3) βgl, we …


Layer-By-Layer Assembled Membranes With Immobilized Porins, Sebastián Hernández, Cassandra Porter, Xinyi Zhang, Yinan Wei, Dibakar Bhattacharyya Dec 2017

Layer-By-Layer Assembled Membranes With Immobilized Porins, Sebastián Hernández, Cassandra Porter, Xinyi Zhang, Yinan Wei, Dibakar Bhattacharyya

Chemical and Materials Engineering Faculty Publications

New and advanced opportunities are arising for the synthesis and functionalization of membranes with selective separation, reactivity, and stimuli-responsive behavior. One such advancement is the integration of bio-based channels in membrane technologies. By a layer-by-layer (LbL) assembly of polyelectrolytes, outer membrane protein F trimers (OmpF) or “porins” from Escherichia coli with central pores ∼2 nm in diameter at their opening and ∼0.7 × 1.1 nm at their constricted region are immobilized within the pores of poly(vinylidene fluoride) microfiltration membranes, in contrast to traditional ruptured lipid bilayer or vesicle processes. These OmpF-membranes demonstrate selective rejection of non-charged organics over ionic solutes, …


Synthesis And Characterization Of Thermoresponsive Hydrogels Based On N-Isopropylacrylamide Crosslinked With 4,4′-Dihydroxybiphenyl Diacrylate, Shuo Tang, Martha Floy, Rohit Bhandari, Manjula Sunkara, Andrew J. Morris, Thomas D. Dziubla, J. Zach Hilt Dec 2017

Synthesis And Characterization Of Thermoresponsive Hydrogels Based On N-Isopropylacrylamide Crosslinked With 4,4′-Dihydroxybiphenyl Diacrylate, Shuo Tang, Martha Floy, Rohit Bhandari, Manjula Sunkara, Andrew J. Morris, Thomas D. Dziubla, J. Zach Hilt

Chemical and Materials Engineering Faculty Publications

A novel crosslinker [4,4′-dihydroxybiphenyl diacrylate (44BDA)] was developed, and a series of temperature-responsive hydrogels were synthesized through free radical polymerization of N-isopropylacrylamide (NIPAAm) with 44BDA. The temperature-responsive behavior of the resulting gels was characterized by swelling studies, and the lower critical solution temperature (LCST) of the hydrogels was characterized through differential scanning calorimetry. Increased content of 44BDA led to a decreased swelling ratio and shifted the LCST to lower temperatures. These novel hydrogels also displayed resiliency through multiple swelling–deswelling cycles, and their temperature responsiveness was reversible. The successful synthesis of NIPAAm-based hydrogels crosslinked with 44BDA has led to a …


Chemically Stable Artificial Sei For Li-Ion Battery Electrodes, Qinglin Zhang, Lei Han, Jie Pan, Zhi Chen, Yang-Tse Cheng Mar 2017

Chemically Stable Artificial Sei For Li-Ion Battery Electrodes, Qinglin Zhang, Lei Han, Jie Pan, Zhi Chen, Yang-Tse Cheng

Chemical and Materials Engineering Faculty Publications

The importance of coating's chemical stability in lithium-ion batteries has been demonstrated by this study. It is well known that the mechanical properties determine the cycle life, and chemical stability or chemical degradation rate determines the calendar life. In this study, we used HfO2 coatings prepared by atomic layer deposition as an example to show the chemical stability of the coatings for lithium ion battery electrodes.


Synthesis And Catalytic Applications Of Non-Metal Doped Mesoporous Titania, Syed Z. Islam, Suraj R. Nagpure, Doo Young Kim, Stephen E. Rankin Mar 2017

Synthesis And Catalytic Applications Of Non-Metal Doped Mesoporous Titania, Syed Z. Islam, Suraj R. Nagpure, Doo Young Kim, Stephen E. Rankin

Chemical and Materials Engineering Faculty Publications

Mesoporous titania (mp-TiO2) has drawn tremendous attention for a diverse set of applications due to its high surface area, interfacial structure, and tunable combination of pore size, pore orientation, wall thickness, and pore connectivity. Its pore structure facilitates rapid diffusion of reactants and charge carriers to the photocatalytically active interface of TiO2. However, because the large band gap of TiO2 limits its ability to utilize visible light, non-metal doping has been extensively studied to tune the energy levels of TiO2. While first-principles calculations support the efficacy of this approach, it is challenging to …