This is a great question because it challenges generally accepted principles of prop torque generated by a piston engine. One clue in the question states "a twisting moment creating by the turbine", and there were thoughts of the slender pylons on jets: is there a torque stress on the motor mounts?.
Certainly a twisting stress on the turbine shift, whether it is run through a transmission or not. So let's load the prop while the jet is running. Notice that blades are symmetrically arranged around the shaft compared with pistons pushing one at a time away from the center of rotation.
The symmetrical push on all the turbine blades by the jet exhaust gasses does not produce a torque force on the mounts, only a torsional stress on the shaft. The symmetrical drag load of the prop blades does not produce a torque force on the mounts, only a torsional stress on the shaft.
One may surmise that if the turbine torque and the prop load torque are balanced around the center of rotation, there is no torque on the motor mount.
However, if one component comes out of balance (such as the prop), the motor mount may be easily torn off.
For more on turbo-prop designs, check out this question. Seems that Pratt and Whitney designers had some thoughts on the torque issue too.
And in this report the "ovalization" of the nacelle seemed to be of greater concern, solved by increasing the pylon attachment points from 1 to 2, spaced 120 degrees apart.