Welcome to patcHwork

patcHwork is a user-friendly web-server that identifies amino acids of proteins that undergo a charge-shift when the pH assumes two user-defined values. For sequence functionality, users may submit a FASTA file with up to ten thousand amino acid sequences (max 20MB). For structure functionality, users may submit a single 3D structure (PDB) file or a zip file with multiple PDB files (max 20MB) for batch processing.

patcHwork is free and open to all users and there is no login requirement.

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To gain a deeper mechanistic understanding of the effect of pH changes on a protein of interest, patcHwork performs an analysis on submitted 3D protein structures using the PDB2PQR and PROPKA tools. The graphic user interface of patcHwork makes it possible to easily locate pH-sensitive residues on the protein structure at two defined pH values as well as to visualize salt bridges, hydrogen bonds and aromatic interactions that change upon pH shift. Furthermore, patcHwork offers the possibility to identify patches of pH-sensitive residues that are in close proximity on the protein structure, as they are likely to have a major impact on protein activity.