A new, free online service to estimate protein isoelectric point is available. At first glance it looks like the ExPASy compute pI/Mw tool or the EMBL WWW Gateway to Isoelectric Point Service. The difference here is that you can choose from up to seven pK value sets. Additionally, you can download a free computer program for pI calculation or learn how to write one in the C++ language.

To the author's best knowledge, it is the only place where the theoretical basics of isoelectric point calculation are sufficiently explained, and based on this knowledge the website explains how to write a simple computer program. In this respect this website is unique, as other web resources are restricted to theory and do not show how to implement anything. And in other cases online programs are veritable black boxes – many times the user does not understand pK values or the structure of an algorithm, even in broad outline.

URL

http://isoelectric.ovh.org