Produced via a proprietary process resulting in a single biotin modification exclusively on the Nterminus of ubiquitin. This site-specific modification results in an ubiquitin that is fully functional at the C-terminus, and with the full compliment of reactive lysines to allow for polyubiquitin chain incorporation. Detection with avidin-linked reagents allows for a higher efficiency and detection sensitivity than with anti-ubiquitin antibodies. Ideal as an alternative to radio-labeled ubiquitin.