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Silica Gel for Enhanced Activity and Hypochlorite Protection of Cyanuric Acid Hydrolase in Recombinant Escherichia coli.

Radian A, Aukema KG, Aksan A, Wackett LP - MBio (2015)

Bottom Line: APTES coating or encapsulation of cells had two benefits: (i) overcoming diffusion limitations imposed by the cell wall and (ii) protecting against hypochlorite inactivation of CAH activity.APTES-encapsulated E. coli cells expressing CAH degraded cyanuric acid at high rates in the presence of 1 to 10 ppm hypochlorite, showing effectiveness under swimming pool conditions.Methods for promoting whole-cell biocatalysis are important in biotechnology, and the present work illustrates approaches to enhance rates and protect against an inhibitory substance.

View Article: PubMed Central - PubMed

Affiliation: BioTechnology Institute, University of Minnesota, St. Paul, Minnesota, USA Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota, USA.

No MeSH data available.


Related in: MedlinePlus

Suggested mechanism of dual functional APTES gels. (A) Illustration of anionic lipids in the cellular membrane interacting electrostatically with the positively charged amine groups, consequently disrupting the outer membrane. (B) Condensation of the APTES precursor to create the amine functionalized silica aggregates and the reaction of the amine groups with hypochlorite to sequester chlorines, delaying enzyme oxidation and enabling sufficient CYA degradation.
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fig9: Suggested mechanism of dual functional APTES gels. (A) Illustration of anionic lipids in the cellular membrane interacting electrostatically with the positively charged amine groups, consequently disrupting the outer membrane. (B) Condensation of the APTES precursor to create the amine functionalized silica aggregates and the reaction of the amine groups with hypochlorite to sequester chlorines, delaying enzyme oxidation and enabling sufficient CYA degradation.

Mentions: The data indicated that the biomaterial developed here has two distinct functionalities: diffusion enhancement (Fig. 9A) and hypochlorite protection (Fig. 9B). Analysis of the degradation rates of cells that were directly reacted with the APTES precursor showed rates comparable to those of purified enzyme, strongly suggesting that the membrane is abrogated and consequently permeable to smaller solutes (Fig. 9A). Despite that, the APTES gel protects and immobilizes the enzyme and as such remains an efficient whole-cell, immobilizing biocatalyst.


Silica Gel for Enhanced Activity and Hypochlorite Protection of Cyanuric Acid Hydrolase in Recombinant Escherichia coli.

Radian A, Aukema KG, Aksan A, Wackett LP - MBio (2015)

Suggested mechanism of dual functional APTES gels. (A) Illustration of anionic lipids in the cellular membrane interacting electrostatically with the positively charged amine groups, consequently disrupting the outer membrane. (B) Condensation of the APTES precursor to create the amine functionalized silica aggregates and the reaction of the amine groups with hypochlorite to sequester chlorines, delaying enzyme oxidation and enabling sufficient CYA degradation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4631802&req=5

fig9: Suggested mechanism of dual functional APTES gels. (A) Illustration of anionic lipids in the cellular membrane interacting electrostatically with the positively charged amine groups, consequently disrupting the outer membrane. (B) Condensation of the APTES precursor to create the amine functionalized silica aggregates and the reaction of the amine groups with hypochlorite to sequester chlorines, delaying enzyme oxidation and enabling sufficient CYA degradation.
Mentions: The data indicated that the biomaterial developed here has two distinct functionalities: diffusion enhancement (Fig. 9A) and hypochlorite protection (Fig. 9B). Analysis of the degradation rates of cells that were directly reacted with the APTES precursor showed rates comparable to those of purified enzyme, strongly suggesting that the membrane is abrogated and consequently permeable to smaller solutes (Fig. 9A). Despite that, the APTES gel protects and immobilizes the enzyme and as such remains an efficient whole-cell, immobilizing biocatalyst.

Bottom Line: APTES coating or encapsulation of cells had two benefits: (i) overcoming diffusion limitations imposed by the cell wall and (ii) protecting against hypochlorite inactivation of CAH activity.APTES-encapsulated E. coli cells expressing CAH degraded cyanuric acid at high rates in the presence of 1 to 10 ppm hypochlorite, showing effectiveness under swimming pool conditions.Methods for promoting whole-cell biocatalysis are important in biotechnology, and the present work illustrates approaches to enhance rates and protect against an inhibitory substance.

View Article: PubMed Central - PubMed

Affiliation: BioTechnology Institute, University of Minnesota, St. Paul, Minnesota, USA Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota, USA.

No MeSH data available.


Related in: MedlinePlus