Improving the accuracy of transmembrane protein topology prediction using evolutionary information

Bioinformatics. 2007 Mar 1;23(5):538-44. doi: 10.1093/bioinformatics/btl677. Epub 2007 Jan 19.


Motivation: Many important biological processes such as cell signaling, transport of membrane-impermeable molecules, cell-cell communication, cell recognition and cell adhesion are mediated by membrane proteins. Unfortunately, as these proteins are not water soluble, it is extremely hard to experimentally determine their structure. Therefore, improved methods for predicting the structure of these proteins are vital in biological research. In order to improve transmembrane topology prediction, we evaluate the combined use of both integrated signal peptide prediction and evolutionary information in a single algorithm.

Results: A new method (MEMSAT3) for predicting transmembrane protein topology from sequence profiles is described and benchmarked with full cross-validation on a standard data set of 184 transmembrane proteins. The method is found to predict both the correct topology and the locations of transmembrane segments for 80% of the test set. This compares with accuracies of 62-72% for other popular methods on the same benchmark. By using a second neural network specifically to discriminate transmembrane from globular proteins, a very low overall false positive rate (0.5%) can also be achieved in detecting transmembrane proteins.

Availability: An implementation of the described method is available both as a web server ( and as downloadable source code from Both the server and source code files are free to non-commercial users. Benchmark and training data are also available from

Publication types

  • Comparative Study
  • Evaluation Study
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Algorithms*
  • Computational Biology
  • Evolution, Molecular
  • Membrane Proteins / chemistry*
  • Protein Conformation
  • Reproducibility of Results
  • Sequence Analysis, Protein / methods*


  • Membrane Proteins