Research concepts
Residue Numbering: Precursors and Fragments
Residue and fragment numbering: Which reference sequence underlies the residue interval?
Source editorial review:
Before interpreting the result
Which reference sequence underlies the residue interval?
- Record whether the reference is a precursor, mature chain or fragment.
- Keep the version, species and terminal modifications.
- Compare the sequence, not merely whether two names share numbers.
Residue and fragment numbering
Sequence numbers are meaningful only with a reference. Precursor, mature chain and fragment may start numbering at different positions. A two-number label does not guarantee two documents describe the same chain. Sequence identifier, version and termini can resolve that ambiguity.
A reading case: what to check
Before combining fragment references, align available sequences against each paper's cited reference. If only numbering is provided and material cannot be reconstructed, leave correspondence unresolved. Do not fill residues from name-based memory. This documentary check can prevent comparing different entities without changing any scientific result.
What to preserve in the record
Numbering without a reference is ambiguous. Aligning sequences before comparing fragments reveals whether the intervals actually describe the same material.
Questions and answers
Which reference sequence underlies the residue interval?
Sequence numbers are meaningful only with a reference. Precursor, mature chain and fragment may start numbering at different positions. A two-number label does not guarantee two documents describe the same chain. Sequence identifier, version and termini can resolve that ambiguity.
What should the review record preserve?
Numbering without a reference is ambiguous. Aligning sequences before comparing fragments reveals whether the intervals actually describe the same material.