The program also incorporates limited functions for ab initio structure prediction of loop regions of proteins, which are often highly variable even among homologous proteins and thus difficult to predict by homology modeling.
Modeller was originally written and is currently maintained by Andrej Sali at the University of California, San Francisco.[4] It runs on the operating systems Unix, Linux, macOS, and Windows. It is freeware for academic use. Graphical user interfaces (GUIs) and commercial versions are distributed by Accelrys. The ModWeb comparative protein structure modeling webserver is based on Modeller and other tools for automatic protein structure modeling, with an option to deposit the resulting models into ModBase. Due to Modeller's popularity, several third party GUIs for MODELLER are available:
EasyModeller is freeware and is one of the earliest third party GUIs for Modeller.[5] Recent version (EasyModeller 4.0) supports Linux and Windows operating system.
^Fiser A, Sali A (2003). "Modeller: Generation and Refinement of Homology-Based Protein Structure Models". Macromolecular Crystallography, Part D. Methods in Enzymology. Vol. 374. pp. 461–91. doi:10.1016/S0076-6879(03)74020-8. ISBN9780121827779. PMID14696385.
^Martí-Renom MA, Stuart AC, Fiser A, Sánchez R, Melo F, Sali A (2000). "Comparative protein structure modeling of genes and genomes". Annu Rev Biophys Biomol Struct. 29: 291–325. doi:10.1146/annurev.biophys.29.1.291. PMID10940251.
^Sali A, Blundell TL (December 1993). "Comparative protein modelling by satisfaction of spatial restraints". J. Mol. Biol. 234 (3): 779–815. doi:10.1006/jmbi.1993.1626. PMID8254673.
^Parida BK, Panda PK, Misra N, Mishra BK (2015). "MaxMod: a hidden Markov model based novel interface to MODELLER for improved prediction of protein 3D models". Journal of Molecular Modeling. 21 (2): 1–10. doi:10.1007/s00894-014-2563-3. PMID25636267. S2CID30626573.