@InProceedings{Waldispuehl:etal:TMBalign:RECOMB09, author = {J{\'e}r{\^o}me Waldisp{\"u}hl and Charles W. O'Donnell and Sebastian Will and Srinivas Devadas and Rolf Backofen and Bonnie Berger}, title = {Simultaneous Alignment and Folding of Protein Sequences}, booktitle = RECOMB09, user = {will}, editor = {Serafim Batzoglou}, publisher = {Springer}, location = {Heidelberg}, series = {LNBI}, volume = 5541, year = 2009, isbn = {978-3-642-02007-0}, pages = {339--355}, abstract = {One of the central challenges in computational biology is to develop accurate tools for protein structure analysis. Particularly difficult cases of this are sequence alignment and consensus folding of low-homology proteins. In this work, we present partiFold-Align, the first algorithm for simultaneous alignment and consensus folding of unaligned protein sequences; the algorithm's complexity is polynomial in time and space. Algorithmically, partiFold-Align additionally exploits sparsity in the set of likely super-secondary structure pairings and alignment candidates for each amino acid to achieve an effectively cubic running time for simultaneous pairwise alignment and folding. We demonstrate the efficacy of these techniques on transmembrane beta-barrel proteins, an important yet difficult class of proteins with very few available three-dimensional structures. In tests on sequence alignments derived from structure alignments, partiFold-Align is significantly more accurate than current best approaches for pairwise sequence alignment in the difficult case of low sequence homology and improves secondary structure prediction when current approaches fail. Importantly, partiFold-Align does not require training on transmembrane beta-barrel proteins. The generality of these techniques should allow them to be applied to a wide variety of protein structures.} }