peptide

peptide

Peptide

Amino acids

getInfo()

Returns an array of information about amino acids

Amino acids sequence

convertAASequence(sequence)

Returns a peptidic sequence from a PDB or one letter code to the internal molecular formula format

Arguments

• sequence - string with the amino acids sequence

chargePeptide(mf)

Add a positive charge on Arg, His and Lys

Arguments

• mf - string with a molecular formula to charge

generatePeptideFragments(mf, [options])

Generate peptide fragmentation. Returns an array of molecular formulas with the different fragments.

Arguments

• mf - string with the molecular formula
• options - object with requested fragments. Default: {a:false, b:true, c:false, x:false, y:true, z:false, i:false}

You can also specify internal fragments using the options 'ya' and 'yb'.

Isoelectric Point

pKa of amino acids is based on https://en.wikipedia.org/wiki/Amino_acid.

calculateCharge(sequence, ph)

Calculate the charge for a specific amino acid sequence. The sequence should be entered in the form "HAlaGlyOH". Please take care about the N and C terminal end. You may use the methods "convertAASequence" to create such a sequence from other format.

Arguments

• sequence - string with the amino acids sequence
• ph - ph for which to calculate the charge. Default: 7.0

calculateIEP(sequence)

Calculate the isoelectric point for a specific amino acid sequence. The sequence should be entered in the form "HAlaGlyOH". Please take care about the N and C terminal end. You may use the methods "convertAASequence" to create such a sequence from other format.

Arguments

• sequence - string with the amino acids sequence

calculateIEPChart(sequence)

Returns an object containing the y and yAbs array of the charge of the peptide for a pH that goes from 0 to 14.

Arguments

• sequence - string with the amino acids sequence

getColorForIEP(iep)

Returns a color based on the isoelectric point :

• 0 -> 7 means that at pH 7 it is charged negatively (blue)
• 7 -> 14 means that at pH7 it is charged positively (red)

Arguments

• iep - the value of the isoelectric point

License

MIT