Application of amino acid occurrence for discriminating different folding types of globular proteins

Background: Predicting the three-dimensional structure of a protein from its amino acid sequence is a long-standing goal in computational/ molecular biology. The discrimination of different structural classes and folding types are intermediate steps in protein structure prediction. Results: In this work, we have proposed a method based on linear discriminant analysis (LDA) for discriminating 30 different folding types of globular proteins using amino acid occurrence. Our method was tested with a non-redundant set of 1612 proteins and it discriminated them with the accuracy of 38%, which is comparable to or better than other methods in the literature. A web server has been developed for discriminating the folding type of a query protein from its amino acid sequence and it is available at http:// granular. com/ PROLDA/. Conclusion: Amino acid occurrence has been successfully used to discriminate different folding types of globular proteins. The discrimination accuracy obtained with amino acid occurrence is better than that obtained with amino acid composition and/or amino acid properties. In addition, the method is very fast to obtain the results.