SequenceTools-Python

A menu-based program for DNA / RNA / Protein operations written in Python (no external libraries).
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)

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How to run

Requirements: Python 3.8+

python seq_cli_purepython.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

4) Mutate (Protein → Protein with 1 substitution)

Choose 4: Insert a random mutation.

Input (Protein): TALPKPG

Output (Mutated Protein): e.g., TALFKPG (position & new AA are random; output varies)