🔍 Missing Residues Finder

Instantly scan your PDB files for structural gaps and missing loops online

Upload Structure

✅ Analysis Results

🎉 Structure Complete

MD Ready

No missing residues were found in the standard amino acid sequence. Your protein appears to be structurally continuous and ready for downstream applications!

ℹī¸ How It Works

X-ray crystallography often leaves highly flexible loops unresolved, resulting in missing residues in the final PDB file. Running MD simulations on incomplete structures can lead to immediate crashes or unphysical behavior. This tool performs a rapid sanity check to map exactly where sequence breaks occur.

1

Upload PDB

Provide your raw protein structure directly from the RCSB or your local machine.

2

Chain Scanning

The tool separates the file by chains and reads the residue indices sequentially.

3

Gap Detection

It mathematically checks for numeric jumps between the first and last standard amino acids.

4

Generate Report

Outputs a clean list of the exact missing residues so you can prepare for loop modeling.

Technical Details

  • Standard Amino Acids Only: The tool intelligently ignores ligands, waters, and heteroatoms, so you don't get false positives for gaps between the protein and the ligand.
  • Preparation Step: If gaps are found, you must use a tool like Modeller, SWISS-MODEL, or PyRosetta to build the missing loops before attempting molecular dynamics in GROMACS or AMBER.

📚 How to Cite

Cite this tool:

ScientiFlow Tools. Available at: https://scientiflow.com

Powered by:

  • Biopython: Cock, P. J., et al. (2009). Biopython: freely available Python tools for computational molecular biology and bioinformatics. Bioinformatics, 25(11), 1422-1423.