Universality classes for depinning transitions of two heteropolymers

We study a solid-on-solid model for depinning transitions of two directed heteropolymers with an effective long range interaction decaying as the inverse square of their distance. Exact calculations of the localization length and specific heat non-universal critical exponents indicate that new universality classes govern the depinning transitions, different from those found for interacting homopolymers. Disorder driven change in the order of the phase transition and in the sign of the specific heat exponent are predicted.