Structural Features and Molecular Evolution of Bowman‐Birk Protease Inhibitors and Their Potential Application

• Published in: Acta biochimica et biophysica Sinica Vol. 37; no. 5; pp. 283 - 292
• Main Authors: QI, Rui‐Feng, SONG, Zhan‐Wu, CHI, Cheng‐Wu
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Pty 01.05.2005
• Subjects: Amino Acid Sequence; Bowman‐Birk protease inhibitor; drug design; Evolution, Molecular; Models, Molecular; molecular evolution; Molecular Sequence Data; Plant Proteins - chemistry; Plant Proteins - genetics; Plant Proteins - metabolism; Protease Inhibitors - chemistry; Protease Inhibitors - metabolism; Protein Conformation; Structure-Activity Relationship; sunflower trypsin inhibitor‐1 (SFTI‐1); Trypsin Inhibitor, Bowman-Birk Soybean - chemistry; Trypsin Inhibitor, Bowman-Birk Soybean - genetics; Trypsin Inhibitor, Bowman-Birk Soybean - metabolism
• ISSN: 1672-9145; 1745-7270
• DOI: 10.1111/j.1745-7270.2005.00048.x

The Bowman‐Birk inhibitors (BBIs) are well‐studied serine protease inhibitors that are abundant in dicotyledonous and monocotyledonous plants. BBIs from dicots usually have a molecular weight of 8k and are double‐headed with two reactive sites, whereas those from monocots can be divided into two classes, one approximately 8 kDa in size with one reactive site (another reactive site was lost) and the other approximately 16 kDa in size with two reactive sites. The reactive site is located at unique exposed surfaces formed by a disulfide‐linked β‐sheet loop that is highly conserved, rigid and mostly composed of nine residues. The structural features and molecular evolution of inhibitors are described, focusing on the conserved disulfide bridges. The sunflower trypsin inhibitor‐1 (SFTI‐1), with 14 amino acid residues, is a recently discovered bicyclic inhibitor, and is the most small and potent naturally occurring Bowman‐Birk inhibitor. Recently, BBIs have become a hot topic because of their potential applications. BBIs are now used for defense against pathogens and insects in transgenic plants, which has advantages over using toxic and polluting insecticides. BBIs could also be applied in the prevention of cancer, Dengue fever, and inflammatory and allergic disorders, because of their inhibitory activity with respect to the serine proteases that play a pivotal role in the development and pathogenesis of these diseases. The canonical nine‐residue loop of BBIs/ STFI‐1 provides an ideal template for drug design of specific inhibitors to target their respective proteases. Edited by You‐Shang ZHANG