Restriction Enzyme Cutter & Mapper

The Learnbin Lab Restriction Cutter & Mapper is a professional-grade bioinformatics utility that simulates the digestion of DNA sequences by restriction endonucleases. Unlike basic text-search tools, this application uses a comprehensive biological database to generate interactive Linear and Circular maps, identifying cut sites with single-base pair accuracy.

1. Biological Theory: How It Works

Restriction enzymes are proteins that recognize specific nucleotide sequences (recognition sites) and cut the DNA at or near those sites. This tool simulates three critical aspects of this process:

• Recognition: It scans your sequence for palindromic patterns (e.g., GAATTC for EcoRI) used by hundreds of commercial enzymes.
• Topology: It distinguishes between Linear DNA (PCR products) and Circular DNA (Plasmids), correctly calculating fragment sizes that wrap around the sequence origin.
• Digestion: It predicts the resulting DNA fragments to simulate how they would migrate in an agarose gel electrophoresis experiment.

2. Key Features

• Dual Visualization: Switch instantly between a Linear Track (for detailed gene analysis) and a Circular Plasmid Map (for vector design).
• Virtual Gel Simulation: A physics-based simulation of an agarose gel run. Compare your actual lab results against the theoretical "band" pattern (using a standard 1kb ladder).
• Smart Enzyme Sets: Choose from common laboratory enzymes (NEB Top 50) or search specific cutters. The tool automatically filters for "Single Cutters" to help you find unique cloning sites.
• Industrial Capacity: Powered by Biopython on a serverless backend, this tool can process bacterial genomes or large viral vectors (up to 5MB) in seconds.

3. Comparison: Learnbin vs. Desktop Software

4. Limitations & Best Practices

To ensure optimal performance in a web environment, the following constraints apply:

• File Size Limit: The tool accepts sequences up to 5 MB (approx. 5 million base pairs). For analyzing entire human chromosomes, desktop software is recommended.
• Visualization Cap: If a sequence contains over 500 cut sites (e.g., using "All Enzymes" on a large genome), the graphical map may simplify to a table view to prevent browser lag.
• Topology: Always ensure you select the correct topology (Linear vs. Circular). Selecting "Linear" for a plasmid will result in incorrect fragment counts (n+1 fragments instead of n).