Selection of cadmium specific hexapeptides and their expression as OmpA fusion proteins in Escherichia coli.
In searching for novel peptides with affinity for cadmium, the phage display technique was utilized. In the selection procedure, cadmium ions were immobilized on a metal chelating Sepharose gel. The peptides selected from a hexapeptide library showed no homology to naturally occurring metallothioneins. From the phage clones selected in the biopanning process, phages with affinity for Cd-109 in free solution were identified. The peptide His-Ser-Gln-Lys-Val-Phe, which was found to exhibit the strongest relative affinity for Cd-109, was cloned into Escherichia coli as a fusion to the cell surface exposed area of the outer membrane protein OmpA. Escherichia coli cells expressing this peptide showed increased survival in growth media containing up to 1.2 mM CdCl2 when compared with cells not expressing this peptide on their surface.
Mejàre
M
M
Department of Pure and Applied Biochemistry, Centre for Chemistry and Chemical Engineering, Lund, Sweden.
Ljung
S
S
Bülow
L
L
D000595:Amino Acid Sequence; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001435:Bacteriophages / Q000235:genetics; D002104:Cadmium / Q000378:metabolism*; D019256:Cadmium Chloride; D002614:Chelating Agents; D003470:Culture Media; D004926:Escherichia coli / Q000235:genetics* / Q000254:growth & development; D015870:Gene Expression; D015723:Gene Library; D009842:Oligopeptides / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D011993:Recombinant Fusion Proteins; D012685:Sepharose; D013329:Structure-Activity Relationship; D015032:Zinc / Q000378:metabolism
D001425:Bacterial Outer Membrane Proteins; D002614:Chelating Agents; D003470:Culture Media; D009842:Oligopeptides; D011993:Recombinant Fusion Proteins; D002104:Cadmium; C078167:OMPA outer membrane proteins; D012685:Sepharose; D015032:Zinc; D019256:Cadmium Chloride