title: Apparent heterogeneity in the pIII-peptide fusion protein in single-phage clones isolated from peptide libraries.
abstract: Ligand homogeneity is an important issue in affinity chromatography. Using phages expressing peptides on the pIII protein, a heterogeneity in the binding of monoclonal phages was observed during affinity chromatography on supermacroporous cryogels. Fractions with different apparent binding affinities could be separated by stepwise elution. When these different fractions were re-applied, the respective differences in affinity were retained. However, when phage fractions with different apparent affinities were first amplified, an offspring was generated with again variable affinities. As the sequence of the peptide insert was the same, the heterogeneity must be ascribed to differences in avidity and although no direct evidence could be generated, we hypothesize that this is possibly due to phages displaying different numbers of the same peptide as a consequence of either proteolytic or packaging events during the amplification step in Escherichia coli.
authors.affiliation: IRF Life Sciences, Katholieke Universiteit Leuven Campus Kortrijk, Kortrijk, Belgium. wim.noppe@kuleuven-kortrijk.be
authors.forename: Wim
authors.initials: W
authors.lastname: Noppe
authors.forename: Igor Yu
authors.initials: IY
authors.lastname: Galaev
authors.forename: Bo
authors.initials: B
authors.lastname: Mattiasson
authors.forename: Hans
authors.initials: H
authors.lastname: Deckmyn
mesh_terms: D000915:Antibody Affinity; D001435:Bacteriophages; D002846:Chromatography, Affinity / Q000379:methods*; D059985:Cryogels; D004926:Escherichia coli; D005434:Flow Cytometry; D006801:Humans; D007781:Lactoferrin / Q000737:chemistry / Q000378:metabolism; D009842:Oligopeptides / Q000737:chemistry / Q000378:metabolism; D019151:Peptide Library; D015202:Protein Engineering / Q000379:methods*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D059985:Cryogels; D009842:Oligopeptides; D019151:Peptide Library; D011993:Recombinant Fusion Proteins; D007781:Lactoferrin