Article

Sequential Reactions of Surface- Tethered Glycolytic Enzymes

Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Chemistry & biology (Impact Factor: 6.65). 09/2009; 16(9):1013-20. DOI: 10.1016/j.chembiol.2009.08.009
Source: PubMed

ABSTRACT

The development of complex hybrid organic-inorganic devices faces several challenges, including how they can generate energy. Cells face similar challenges regarding local energy production. Mammalian sperm solve this problem by generating ATP down the flagellar principal piece by means of glycolytic enzymes, several of which are tethered to a cytoskeletal support via germ-cell-specific targeting domains. Inspired by this design, we have produced recombinant hexokinase type 1 and glucose-6-phosphate isomerase capable of oriented immobilization on a nickel-nitrilotriacetic acid modified surface. Specific activities of enzymes tethered via this strategy were substantially higher than when randomly adsorbed. Furthermore, these enzymes showed sequential activities when tethered onto the same surface. This is the first demonstration of surface-tethered pathway components showing sequential enzymatic activities, and it provides a first step toward reconstitution of glycolysis on engineered hybrid devices.

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Available from: Chinatsu Mukai, Feb 20, 2014
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    • "After showing the activity of the enzymes tethered individually, we then demonstrated the activity of the coupled reaction with both enzymes tethered to the same support (Fig. 4). To our knowledge, we believe this was the first demonstration of coupled enzyme activities of sequential steps of a pathway on a single surface (Mukai et al. 2009). This finding is an important first step toward a platform technology based on tethered glycolytic enzymes that could provide energy for hybrid organic–inorganic devices (Hess 2009). "
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