Apolipoprotein A-II (ApoA-II) is the second major apolipoprotein of high density lipoprotein in human plasma. Mature ApoA-II is present as a dimer of two 77-amino acid chains joined by a disulphide bridge [1]. ApoA-II regulates many steps in HDL metabolism, and its role in coronary heart disease is unclear [1]. In bovine serum, the ApoA-II homologue is present in almost free form. Bovine ApoA-II shows antimicrobial activity against Escherichia coli and yeasts in phosphate buffered saline (PBS) [2].

1: Apolipoprotein A-II, HDL metabolism and atherosclerosis. Tailleux A, Duriez P, Fruchart JC, Clavey V; Atherosclerosis 2002;164:1-13. PMID:12119188

2: Purification, primary structure, and antimicrobial activities of bovine apolipoprotein A-II. Motizuki M, Itoh T, Yamada M, Shimamura S, Tsurugi K; J Biochem (Tokyo) 1998;123:675-679. PMID:9538260