Single-molecule force spectroscopy for studying kinetics of enzymatic dextran elongations.

Abstract

Catalytic elongation of dextran by a single molecule of dextransucrase (DSase) was directly monitored by observing the movements of the positions of a rupture peak, which represented the adhesive force between an isomaltoheptaose (dextran 7-mer)-immobilized probe and a DSase-immobilized mica surface. This was initiated with the addition of sucrose monomers. From the histograms of the rupture peaks after elongation reactions on each individual enzyme and the continuous peak shift of certain single enzymes, the catalytic elongation rate constant (k(cat)) was ascertained to be 1.2-2.7 s(-1).

• Authors: Toshiaki Mori, Megumi Asakura, Yoshio Okahata
• Journal: Journal of the American Chemical Society (J Am Chem Soc) Vol. 133 Issue 15 Pg. 5701-3 (Apr 20 2011) ISSN: 1520-5126 [Electronic] United States
• PMID: 21443256 (Publication Type: Journal Article)

Chemical References

• Dextrans
• Enzymes, Immobilized
• Sucrose
• Glucosyltransferases
• dextransucrase

Topics

• Dextrans (metabolism)
• Enzymes, Immobilized (metabolism)
• Glucosyltransferases (metabolism)
• Kinetics
• Spectrum Analysis (methods)
• Sucrose (metabolism)