Learning and reference
Read worked examples and look up the reference data used by the peptide and protein sequence tools.
Learning guides
- Peptide Molecular Weight Formula
Calculate peptide mass by summing residue masses and adding one water molecule. Follow a worked example for ACD.
- Average vs. Monoisotopic Mass
Compare isotope-weighted and monoisotopic peptide masses and see how the two calculations differ for the same sequence.
- What Is the Isoelectric Point?
Understand how pH affects peptide net charge, how a sequence model estimates pI, and what can shift experimental results.
- How to Read a Protein FASTA Record
Identify the FASTA header and sequence lines, then prepare a single protein record for analysis in ResidueBench.
- How to Interpret a Protein Hydropathy Plot
Read the axes and compare two sliding windows on the same sequence to see what a Kyte–Doolittle hydropathy plot can tell you.
- Protein Extinction Coefficient at 280 nm
Relate molar extinction coefficient to measured A280 and compare the reduced and hypothetical disulfide estimates for the same sequence.
Reference tables
- Amino Acid Residue Masses
Look up average and monoisotopic residue masses for the 20 standard amino acids and the terminal water correction.
- Amino Acid pKa Values for pI Estimation
Look up the Bjellqvist pKa values used by ResidueBench, including side chains, terminal defaults, and residue-specific overrides.
- Amino Acid Codes Reference
Look up one-letter and three-letter codes for the 20 standard amino acids and find out what ambiguous, unknown, and rare residue codes mean.