In this work Differential Evolution (DE) was combined with fragment replacement for improving the search of protein structure conformations with minimum energy. The Rosetta environment was used, employing some of its phases for the ab initio prediction in the initialization of the genetic population, as well as its fragment-assembly technique. DE provides a global search in the multimodal energy landscape whereas fragment replacement based on the Monte-Carlo procedure provides a useful search of short protein conformations that accelerates the DE search. Initial results with proteins from PDB with a comparison with previous works are provided.