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Engineering Surfaces to Enhance the Activity of Tethered Enzymes and to Rescue Misfolded Proteins.

紀錄類型:	書目-電子資源 : Monograph/item
正題名/作者:	Engineering Surfaces to Enhance the Activity of Tethered Enzymes and to Rescue Misfolded Proteins./
作者:	Chaparro Sosa, Andres Felipe.
出版者:	Ann Arbor : ProQuest Dissertations & Theses, : 2021,
面頁冊數:	212 p.
附註:	Source: Dissertations Abstracts International, Volume: 82-12, Section: B.
Contained By:	Dissertations Abstracts International82-12B.
標題:	Chemical engineering. -
電子資源:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28415248
ISBN:	9798515204020

Engineering Surfaces to Enhance the Activity of Tethered Enzymes and to Rescue Misfolded Proteins.
Chaparro Sosa, Andres Felipe.

Engineering Surfaces to Enhance the Activity of Tethered Enzymes and to Rescue Misfolded Proteins. - Ann Arbor : ProQuest Dissertations & Theses, 2021 - 212 p.

Source: Dissertations Abstracts International, Volume: 82-12, Section: B.

Thesis (Ph.D.)--University of Colorado at Boulder, 2021.

This item is not available from ProQuest Dissertations & Theses.

Retaining the stability of proteins at the solid-liquid interface is of extreme importance in multiple biotechnological applications, including biosensing, biocatalysis, pharmaceutical production, and sustainability. Unfortunately, interactions with surface materials often lead to a significant decrease in the structural stability of proteins, and thus, reduction in the activity of enzymes. This loss of structure and activity of proteins may be attributed to the vastly different environment that synthetic surfaces provide compared to the native environment of proteins inside of cells. These synthetic materials can cause perturbative interactions that lead to protein denaturation. Moreover, because each protein exhibits unique properties, a material that stabilizes one protein may destabilize another protein. Thus, a major challenge in this field has been the discovery of rules that permit the rational design of strategies and materials that stabilize a given protein under a wide range of conditions.To address these challenges, the thesis presented here aimed to increase the understanding of protein interactions with materials. Notably, single-molecule (SM) tracking methods enabled the direct observation of individual proteins as they adsorbed, diffused, desorbed and/or became immobilized, as well as when they unfolded or refolded on surfaces. This information was essential for correlating the dynamic behavior of proteins with material properties, thereby illuminating important considerations for the design of materials that preserve the stability of proteins. Firstly, we investigated the effects of ligation efficiency on the stability and activity retention of immobilized enzymes. SM results demonstrated that while enzymes readily unfolded on material surfaces after adsorption, by increasing the ligation reaction kinetics, marked improvements in the retention of immobilized enzyme activity and structure could be achieved. Next, we utilized lipid bilayers (LBs) as biomimetic support materials for enzyme immobilization as their properties, including charge and hydrophobicity, may be readily tuned via mixing lipids that have different polar head groups or hydrophobic tail groups. Through the use of SM experiments, the effects of LB composition on the stability of immobilized enzymes was investigated. Notably, our results showed that LB net charge and compositional heterogeneity were both important factors for protein stability. Remarkably, enzymes immobilized on optimal LB compositions remained predominantly folded and active even under extremely denaturing conditions (7 m urea and high temperatures). Interestingly, the stabilization of enzymes on LBs was strongly correlated to an enhancement in the re‐folding rate and was therefore attributed to a chaperone‐like effect, whereby the bilayer actively mediated the re‐folding of denatured enzymes. Finally, we explored the use of this chaperone-like activity of LBs as a potential treatment for neurodegenerative diseases caused by the misfolding and aggregation of proteins. Specifically, the effects of lipid vesicle composition on the inhibition of Aβ fibrillation were investigated. Remarkably, vesicles with optimal lipid composition not only inhibited fibril formation, but more importantly, degraded matured fibrils. Together, these results shed light on the rational design of materials to retain the stability and activity of immobilized enzymes, and of proteins in general.

ISBN: 9798515204020Subjects--Topical Terms:

560457
Chemical engineering.
Subjects--Index Terms:

Amyloid fibrils

Engineering Surfaces to Enhance the Activity of Tethered Enzymes and to Rescue Misfolded Proteins.
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245 1 0 $a Engineering Surfaces to Enhance the Activity of Tethered Enzymes and to Rescue Misfolded Proteins.
260 1 $a Ann Arbor : $b ProQuest Dissertations & Theses, $c 2021
300 $a 212 p.
500 $a Source: Dissertations Abstracts International, Volume: 82-12, Section: B.
500 $a Advisor: Kaar, Joel;Schwartz, Daniel K.
502 $a Thesis (Ph.D.)--University of Colorado at Boulder, 2021.
506 $a This item is not available from ProQuest Dissertations & Theses.
506 $a This item must not be sold to any third party vendors.
520 $a Retaining the stability of proteins at the solid-liquid interface is of extreme importance in multiple biotechnological applications, including biosensing, biocatalysis, pharmaceutical production, and sustainability. Unfortunately, interactions with surface materials often lead to a significant decrease in the structural stability of proteins, and thus, reduction in the activity of enzymes. This loss of structure and activity of proteins may be attributed to the vastly different environment that synthetic surfaces provide compared to the native environment of proteins inside of cells. These synthetic materials can cause perturbative interactions that lead to protein denaturation. Moreover, because each protein exhibits unique properties, a material that stabilizes one protein may destabilize another protein. Thus, a major challenge in this field has been the discovery of rules that permit the rational design of strategies and materials that stabilize a given protein under a wide range of conditions.To address these challenges, the thesis presented here aimed to increase the understanding of protein interactions with materials. Notably, single-molecule (SM) tracking methods enabled the direct observation of individual proteins as they adsorbed, diffused, desorbed and/or became immobilized, as well as when they unfolded or refolded on surfaces. This information was essential for correlating the dynamic behavior of proteins with material properties, thereby illuminating important considerations for the design of materials that preserve the stability of proteins. Firstly, we investigated the effects of ligation efficiency on the stability and activity retention of immobilized enzymes. SM results demonstrated that while enzymes readily unfolded on material surfaces after adsorption, by increasing the ligation reaction kinetics, marked improvements in the retention of immobilized enzyme activity and structure could be achieved. Next, we utilized lipid bilayers (LBs) as biomimetic support materials for enzyme immobilization as their properties, including charge and hydrophobicity, may be readily tuned via mixing lipids that have different polar head groups or hydrophobic tail groups. Through the use of SM experiments, the effects of LB composition on the stability of immobilized enzymes was investigated. Notably, our results showed that LB net charge and compositional heterogeneity were both important factors for protein stability. Remarkably, enzymes immobilized on optimal LB compositions remained predominantly folded and active even under extremely denaturing conditions (7 m urea and high temperatures). Interestingly, the stabilization of enzymes on LBs was strongly correlated to an enhancement in the re‐folding rate and was therefore attributed to a chaperone‐like effect, whereby the bilayer actively mediated the re‐folding of denatured enzymes. Finally, we explored the use of this chaperone-like activity of LBs as a potential treatment for neurodegenerative diseases caused by the misfolding and aggregation of proteins. Specifically, the effects of lipid vesicle composition on the inhibition of Aβ fibrillation were investigated. Remarkably, vesicles with optimal lipid composition not only inhibited fibril formation, but more importantly, degraded matured fibrils. Together, these results shed light on the rational design of materials to retain the stability and activity of immobilized enzymes, and of proteins in general.
590 $a School code: 0051.
650 4 $a Chemical engineering. $3 560457
650 4 $a Bioengineering. $3 657580
650 4 $a Neurosciences. $3 588700
650 4 $a Biophysics. $3 518360
653 $a Amyloid fibrils
653 $a Enzyme immobilization
653 $a Lipid bilayers
653 $a Protein engineering and stability
653 $a Single molecule tracking
653 $a Ligation efficiency
653 $a Denatured enzymes
653 $a Neurodegenerative diseases
653 $a Protein aggregation
653 $a Fibril formation
690 $a 0542
690 $a 0202
690 $a 0786
690 $a 0317
710 2 $a University of Colorado at Boulder. $b Chemical and Biological Engineering. $3 3428945
773 0 $t Dissertations Abstracts International $g 82-12B.
790 $a 0051
791 $a Ph.D.
792 $a 2021
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=28415248