Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:6.2.1.1 (
ACS
)
78,556
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Using a microarray-based assay, we studied how the substitution of amino acids in the immediate vicinity of the receptor-binding domain on a peptide affects its binding to a protein. Replicates of 802 linear peptides consisting of the variants of WT
HPQ
FAT and LQW
HPQ
AGK
, GKFPIPLGKQSG, and NGQFQVWIPGAQK, different by one amino acid, were synthesized on a glass slide with a maskless photolithography. Using a microarray-compatible label-free optical sensor, we measured the binding curves of streptavidin with the synthesized peptides and extracted the streptavidin-peptide affinity constants. We found that (a) the substitution of one residue in the
HPQ
motif reduces the affinity constant
K
a
from 10
8
M
-1
by at least 3-4 orders of magnitude, with an exception of
HPM
; (b) substitution of the immediate flanking residue on the Gln side also causes the affinity to decrease by up to 3-4 orders of magnitude, depending on the substituting residue and the second-neighboring flanking residue; (c) substitution of the flanking residues on the His side has no significant effect on the affinity, possibly due to the strong binding of streptavidin to
HPQ
F and
HPQ
AG motifs. We also found that some of amino acid residues located close to the C-terminus (and the solid surface) improve the yield of peptide synthesis on a glass surface and can be exploited in the fabrication of peptide microarrays.
ACS
Omega 2017 Sep 30
PMID:Single Amino Acid Substitution in the Vicinity of a Receptor-Binding Domain Changes Protein-Peptide Binding Affinity. 3145 12
