UNLABELLED A protein's isoelectric point or pI corresponds to the solution pH at which its net surface charge is zero. Since the early days of solution biochemistry, the pI has been recorded and reported, and thus literature reports of pI abound. The Protein Isoelectric Point database (PIP-DB) has collected and collated these data to provide an increasingly comprehensive database for comparison...

Proteome-pI is an online database containing information about predicted isoelectric points for 5029 proteomes calculated using 18 methods. The isoelectric point, the pH at which a particular molecule carries no net electrical charge, is an important parameter for many analytical biochemistry and proteomics techniques, especially for 2D gel electrophoresis (2D-PAGE), capillary isoelectric focus...

One of the most common techniques for separating mixtures of proteins is the two-dimensional polyacrylamide gel. In these gels, proteins are separated in one dimension based on their electromigration speeds through the gel (roughly determined by their molecular weights) and in another dimension by the pH at which their side chains cumulatively amount to a neutral charge, called the isoelectric ...

This study was undertaken to compare the isoelectric points of gram positive and gram negative bacterial cells by the method of microelectrophoresis. Within recent years a number of workers have referred to differences in the isoelectric point of the gram positive and the gram negative groups of bacteria. This concept arose from the studies of Stearn and Steam (1924, 1925, 1928), Tolstoouhov (1...