Selection of novel nickel-binding peptides from flagella displayed secondary peptide library.
Nickel (Ni) performs its biological or toxic functions in nickel-protein coordination form. Novel Ni-binding peptides were isolated from a random dodecapeptide library displayed on the flagella of Escherichia coli against immobilized ions. On the basis of isolated sequences rich in histidine residues, two secondary libraries were constructed respectively. By consequent selection, more Ni-chelating peptides were identified and the consensus motif RHXHR (where X was always H) was deduced. The result suggested that not only histidine, but also arginine, play an important role in Ni-binding. Furthermore, two selected clones (1035 and 2022) were chosen for further identification. They exhibited similar relative binding affinity, which was about nine times that of the original library derived clones and statistically much more significant than the positive control with polyhistidine insert. Free nickel ions could almost completely inhibit the binding of the clones 1035 and 2022 to immobilized nickel, implicating that the peptides were able to chelate nickel ions. These studies reveal that bacterial surface displayed peptide libraries may have promising future potential for the development of metal bioadsorbents. Furthermore, novel Ni-binding peptides may provide lead molecules for Ni-chelation and applications thereof.
Dong
Jie
J
Department of Biochemistry, Beijing Institute of Basic Medical Sciences, P.O. Box 130(3) Beijing 100850, People's Republic of China.
Liu
Chuan
C
Zhang
Jie
J
Xin
Zhong-Tao
ZT
Yang
Guang
G
Gao
Bo
B
Mao
Can-Quan
CQ
Liu
Nong-Le
NL
Wang
Fang
F
Shao
Ning-Sheng
NS
Fan
Ming
M
Xue
Yan-Ning
YN
D000595:Amino Acid Sequence; D001483:Base Sequence; D001667:Binding, Competitive; D017931:DNA Primers; D004926:Escherichia coli / Q000737:chemistry; D005407:Flagella / Q000737:chemistry*; D009532:Nickel / Q000378:metabolism*; D019151:Peptide Library; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism
D017931:DNA Primers; D019151:Peptide Library; D010455:Peptides; D009532:Nickel