Proteins that are essentially sequences of amino acids, adopt specific folded 3-dimensional (3D) structures to perform their specific tasks. However, misfolded proteins cause fatal diseases. Hence, protein structure prediction (PSP) has emerged as an important multi-disciplinary research problem. Given a protein sequence, the PSP problem is to find a 3D structure of the protein such that the total free energy amongst the amino acids in the sequence is minimised. In-vitro laboratory methods are time-consuming, expensive, and failure-prone. Conversely, computational methods are NP-hard even when the models are simplified by using low-resolution energy functions and lattice-based structures.