Roland Josuran

About Roland Josuran

Prediction of potential modification sites in proteins

Some sequence motifs in proteins tend to be modified. Thus, for example an N-terminal glutamine or glutamic acid residue can spontaneously lead to a cyclization. This reaction results in an N-terminal pyroglutamic acid with elimination of ammonia or water, respectively. Aspartyl and asparaginyl deamidation, isomerization, and racemization reactions can spontaneously occur, if the subsequent amino acid […]

Molecular mass and isoelectric point calculator for glycosylated proteins

Glycosylations should not be neglected for the correct calculation of the molecular mass, the isoelectric point and the mass-specific UV absorption coefficient. Therefore Prot pi provides a tool to draw glycans as a posttranslational modification of proteins. This short guide deals with how to add two complex-type N-Glycosylation G1 with a sialic acid (N-acetylneuraminic acid) […]

Isoelectric point calculation of native proteins

The isoelectric point (pI) of native (not denaturated) proteins is important in several separation techniques. The pI is defined as the pH value at which the positive and negative charges on the protein are balanced and the net charge is zero. To determine the pH at which the net charge is zero, the charge on […]