Title
A salt-switchable artificial cellulase regulated by a DNA aptamer
Author
Mari Takahara, Geisa A. L. G. Budinova, Hikaru Nakazawa, Yutaro Mori, Mitsuo Umetsu, Noriho Kamiya
Year
2016
Journal
Biomacromolecules
Abstract
A novel artificial cellulase was developed by conjugating a DNA aptamer to an endoglucanase catalytic domain, thereby substituting the natural carbohydrate-binding module. Circular dichroism spectroscopy and adsorption isotherm showed the binding motif of cellulose-binding DNA aptamer (CelApt) was G-quadruplex and stem-loop structures stabilized in the presence of salts, and CelApt binding preferred the amorphous region of the solid cellulose. By introducing the revealed salt-switchable cellulose-binding nature of CelApt into a catalytic domain of a cellulase, we created CelApt-catalytic domain conjugate possessing both controllable adsorption on the solid substrates and equal enzymatic activity to the wild-type cellulase. Thus potential use of a responsive DNA aptamer for biocatalysis at a solid surface was demonstrated.
Instrument
J-820
Keywords
Circular dichroism, DNA structure, Ligand binding, Biochemistry