Updated publication reference for PubMed record(s): 30362765. How to separate hydrophobic peptides and to prevent loss of such peptides, nevertheless, have not been drawn enough attention (19). As a membrane protein possesses higher hydrophobicity, especially for one with multiple bilayer-exposed domains, efficient detection of hydrophobic peptides becomes a critical issue for its identification. It is generally recognized that MPs have two characteristics, relatively shorter sequences of amino acids and higher hydrophobicity.