SequenceTools-Biopython

A menu-based program for DNA / RNA / Protein operations written in Python using Biopython library.
Originally built for my Bioinformatics coursework and later refined and polished for clarity.

Purpose: show how to automate basic sequence tasks with clean, readable code that anyone can run from a terminal.

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Core principles

The script reads your sequence as text.

• Complements a DNA sequence: A ↔ T, C ↔ G
• Transcribes DNA → RNA: T → U
• Translates RNA → Protein: 3 RNA letters (a codon) → 1 amino acid
• Inserts a random substitution in a protein (single amino-acid mutation)

The script uses Bio.Seq objects to represent and manipulate sequences.

Calls .complement(), .transcribe(), .translate() directly from Biopython.

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How to run

Requirements:

• Python 3.8+
• Biopython. Install with this line:

pip install biopython

To run the file:

python seq_cli_biopython.py

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Concrete examples (input → output)

1) Complement (DNA → cDNA)

The user enters a DNA sequence, chooses 1: Complement.

Input (DNA): ACGGCCTTGCCTAAACCGGGC

Output (Complement): TGCCGGAACGGATTTGGCCCG

2) Transcribe (DNA → RNA)

Choose 2: Transcribe.

Input (DNA): ACGGCCTTGCCTAAACCGGGC

Output (RNA): ACGGCCUUGCCUAAACCGGGC

3) Translate (RNA → Protein)

Choose 3: Translate.

Input (RNA): ACGGCCUUGCCUAAACCGGGC

Output (Protein): TALPKPG

In case the number of nucelotides is not a multiple of 3, an error message will be displayed (see below)

4) Protein operations (not developed yet in this program)

As operations on protein sequences are not included in this program, the following messsage will be displayed (check below)

More operations on protein/amino acids sequences are to be found in future repositories.