Calculate amino acid composition and statistical analysis of protein sequences.
Paste one or more FASTA sequences (max 500,000,000 characters).
Paste one or more protein sequences in FASTA format using standard one-letter amino acid codes. The tool accepts sequences up to 500 million characters and automatically removes invalid characters. You can analyze multiple proteins simultaneously.
Results group amino acids by chemical properties: Aliphatic (G, A, V, L, I - nonpolar), Aromatic (F, W, Y - ring structures), Sulfur-containing (C, M), Basic (K, R, H - positive), Acidic (D, E - negative), Hydroxyl (S, T), and Amide (N, Q). These categories help predict protein behavior and stability.
The output shows both counts and percentages for each amino acid and category. High percentages of hydrophobic residues suggest membrane proteins, while high charged residue content indicates soluble proteins. Cysteine content hints at disulfide bond formation potential.
Use this analysis for predicting protein solubility, identifying unusual amino acid bias, comparing homologous proteins across species, quality checking recombinant proteins, and understanding sequence-structure-function relationships in protein engineering projects.
Amino acid composition is the percentage or count of each amino acid residue in a protein sequence. This information is useful for understanding protein properties, predicting protein behavior, and comparing sequences across different organisms.