Disulfide Bond Capacity
Compute the maximum number of intrachain disulfides from cysteine count.
Description
Disulfide capacity counts how many cysteine pairs could be formed in one chain.
Disulfide capacity counts how many cysteine pairs could be formed in one chain. Pair capacity is distinct from actual bond count or pairing.1
Compute the maximum number of intrachain disulfides from cysteine count.
When to use Disulfide Bond Capacity
Use this tool to compute the maximum number of intrachain disulfides from cysteine count.
Prepare the canonical sequence, peptide assignments, fitted assay parameters or upstream measurements requested. Keep corresponding entries aligned, use the stated mass and signal units, and remove FASTA headers before entering sequence text.
How to use Disulfide Bond Capacity and understand its results
- Prepare the canonical sequence, peptide assignments, fitted assay parameters or upstream measurements requested. Keep corresponding entries aligned, use the stated mass and signal units, and remove FASTA headers before entering sequence text.
- Enter sequence using the field table and calculation rules, then run the tool.
- Read cysteineCount, maxDisulfideBonds, unpairedCysteines. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| sequence | Sequence | string | Required |
Enter a canonical sequence. Return cysteine count, maximum pair count and parity remainder.
The shared sequence helper trims outer whitespace and uppercases the sequence. It requires at least one residue from ACDEFGHIKLMNPQRSTVWY. Internal whitespace, FASTA headers, ambiguous letters and modified-residue notation are rejected. Sequence indexes refer to the normalized sequence; individual tools may preserve original strings in their returned lists as explained above.
maximumBonds=floor(Ccount/2); unpaired=Ccount mod2 Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| cysteineCount | Cysteine count | number |
| maxDisulfideBonds | Max disulfide bonds | number |
| unpairedCysteines | Unpaired cysteines | number |
{
"input": {
"sequence": "ACCC"
},
"output": {
"cysteineCount": 3,
"maxDisulfideBonds": 1,
"unpairedCysteines": 1
}
}Limitations and assumptions
The remainder assumes maximal pairing. Accessibility, oxidation state, interchain bonds and disulfide arrangement are not inferred.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Extremely large text inputs are rejected. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Protein Extinction 280: Estimate 280-nm molar extinction coefficient from Trp, Tyr, and cystine. For a complementary task, use Protein Elemental Formula: Sum C/H/N/O/S protein elemental formula from residue compositions and termini.
References
-
Disulfide Bond Capacity — tool.io
Similar or alternative tools
- Protein Extinction 280
Estimate 280-nm molar extinction coefficient from Trp, Tyr, and cystine.
- Protein Elemental Formula
Sum C/H/N/O/S protein elemental formula from residue compositions and termini.