The software get a PDB file and do single mutation on it. Mutant coordinate file which generated after minimization with NAMD  will be returned as output. The user should insert chain id and residue number of original amino acid that wish to mutate.Due to the minimization with NAMD if your PDB file contains DNA associated with protein, please isolate protein from it, then upload your coordinate file, otherwise, the software will be crashed and will return no mutant coordinate.