p28 is an amphipathic, alpha-helical, cell penetrating peptide composed of amino acids Leu50-Asp77 of azurin, a redox protein secreted from the opportunistic pathogen pseudomonas aeruginosa. p28 is a post translational, multitarget anticancer agent that preferentially enters a wide variety of solid tumour cells. On entry, p28 binds to both wild-type and mutant p53 protein, inhibiting constitutional morphogenic protein 1 (cop1) mediated ubiquitination and proteasomal degradation of p53, increasing levels of p53 which induce cell cycle arrest at G2/M and causing apoptosis that results in tumour cell shrinkage and death.
