PDB File Analyzer for Protein Structure Validation and Quality Assessment

Abstract

A comprehensive tool for analyzing PDB protein structure files. Features include structure validation, quality metrics calculation, residue interaction analysis, and visualization support for bioinformatics research.

Cleaned Submission Note

This revision replaces a raw JSON display with readable Markdown. The underlying tool description and skill instructions are preserved.

Tool Summary

Analyzes PDB files to extract structural information, amino acid composition, active sites, and ligand interactions. PDB Structure Analyzer 1.0.0

Input Schema

The original structured input schema is retained conceptually. Use the SKILL section below for executable instructions.

SKILL

SKILL: PDB Structure Analyzer

Name

PDB Structure Analyzer

Description

Analyzes PDB (Protein Data Bank) files to extract structural information, amino acid composition, active sites, ligand interactions, and other biochemical properties. Generates comprehensive markdown reports suitable for research documentation.

Input

• Parameter: PDB file path (local) or PDB ID (e.g., "1ABC")
• Type: String
• Examples:
  • Local file: /path/to/structure.pdb
  • PDB ID: 1ABC

Steps

Step 1: Read PDB File

1.1 Accept input PDB file path or ID
1.2 If PDB ID, download PDB file using RCSB PDB API
1.3 Read PDB file content
1.4 Parse structure using Biopython PDBParser

Step 2: Extract Atom Coordinates and Residue Information

2.1 Iterate through all models (usually only 1)
2.2 Iterate through all chains (Chain A, B, C...)
2.3 Extract for each residue:
    - Residue name (e.g., ALA, GLY, PRO)
    - Residue sequence position
    - Amino acid type
2.4 Extract for all atoms:
    - Atom name (C, N, O, S...)
    - Coordinates (x, y, z)
    - Temperature factor (B-factor)

Step 3: Calculate Structural Properties

3.1 Resolution - extracted from EXPDTA record
3.2 R-factor - extracted from CRYST1 or REMARK records
3.3 Experimental method - e.g., X-RAY, NMR, Cryo-EM
3.4 Chain count statistics
3.5 Residue count statistics
3.6 Atom count statistics
3.7 Calculate molecular weight (estimated)

Step 4: Identify Ligands and Metal Ions

4.1 Identify non-standard residues (ligands)
4.2 Identify metal ions (Mg, Zn, Fe, Ca, Na, K, etc.)
4.3 Identify water molecules (HOH)
4.4 Extract ligand chemical formula and name

Step 5: Generate Structure Report

5.1 Generate complete report in Markdown format
5.2 Include structure summary table
5.3 Include amino acid composition analysis
5.4 Include ligand and metal ion list
5.5 Output to specified file or stdout

Output

• Format: Markdown formatted structural analysis report
• Content:
  • Basic structural information summary
  • Experimental methods and technical parameters
  • Chain and residue statistics
  • Amino acid composition histogram/table
  • Ligand and metal ion list
  • Structural quality metrics

Tool Requirements

• Python libraries:
  • biopython - PDB file parsing
  • requests - Download remote PDB files (only when input is PDB ID)
• Local execution: Supported

Execution Command

python execute.py <pdb_path_or_id> [output_file]

Error Handling

• File not found: Return error message
• Invalid PDB ID: Try downloading from RCSB, report error if failed
• Parsing failure: Report specific parsing error

Example Output

See expected_output.txt

Integrity Note

This is a formatting cleanup revision. It does not introduce a new scientific claim.