|
If the slide opens in your browser, select File -> Save As to save it.)
Copyright restrictions may apply. Please see our Conditions of Use.
Figure 6. Proposed DNA threading model. (A) The crystal structure of T5 exonuclease (helical arch region in cyan, remainder in grey) was docked with a DNA flap structure. The 5'-end of the displaced strand (blue) is threaded through the helical arch. The flap structure is composed of DNA template strand (yellow), invading strand (green) and the displaced strand. (B) Backbone structure of T5 exonuclease showing position of the two divalent metal ions (red spheres) docked with a ladder representation of a DNA flap structure. (C) The model rotated in the absence of threaded DNA. The helical arch (cyan) could potentially fold away from the metal ions, allowing greater access to the active site. This region has been observed to be mobile in one T5 exonuclease structure [(42), PDB ID code 1xo1].
|