Screening An
α-glucosidase Inhibitor from A Phage-displayed Peptide Library
LI Jia-Da, WANG Ke-Yi*
( Institute of Biochemistry and Cell Biology, Shanghai Institutes for
Biological Sciences, the Chinese Academy of Sciences, Shanghai 200031,
China )
Abstract A
phage-displayed peptide library was biopanned with Aspergillus niger
glucoamylase. Three specifically binding phage clones (GB-1, GB-2 and GB-3)
were identified after three cycles of screening and amplification. All three
peptides contained a disulfide bridge, and the impairment of disulfide bond
greatly lowered the binding activity. One peptide, cyclic KCHFEECLAY,
representing the N-terminal 10 amino acid residues from GB-1, competitively
inhibited A.niger glucoamylase (Ki＝0.2 mmol/L) as well as rat
intestinal α-glucosidase (Ki＝1.4 mmol/L).
Key words phage display peptide library； biopanning； α-glucosidase inhibitor
*Corresponding author： Tel, 86-21-64374430-5264； Fax, 86-21-64338357； e-mail,
[email protected]