Sortase A Mediated Protein Modifications and Peptide Conjugations

Bioactive peptides regulate many physiological processes, acting at some sites as endocrine or paracrine signals and at others as neurotransmitters or growth factors, and show useful properties for human health, including antimicrobial, antifungal, antiviral, and antitumor activities. Although most peptides can be produced using the molecular biology approach, they are produced in limited quantities at high costs and associated with some difficulties in purification and isolation. In addition, some peptides with special structures, such as cyclic peptides, can hardly be produced by the biological method. This is especially true for the biomedical applications in which long peptides with many repeated functional sequences are usually needed. Prokaryotic transpeptidase Sortase A mediates sequence specific peptide ligation and represents a new method for peptide modifications. Besides peptide and protein modifications to improve stability and specificity of therapeutic peptides, Sortase A mediated peptide ligation has been extended to wider applications such as molecular sensing, surface modification, and biomaterials. In this review, we will focus the pharmacological applications of Sortase A for the production of nucleic acid-peptide conjugates, glycosylated peptides, modified proteins/antibodies, and cyclic peptides.