ds18b20 re map to pinPE7 on 2560

I need help please , i have a prebuilt board that has a atmel2560 onboard and pin PE7 (unmapped in arduino) is attached to data line on ds18b20,, can anyone point me in the right direction so that i can use this pin for reading the ds18b20, i just dont know how to tell one_wire how to address this pin, unfortunately its not an option to change this pin