title: Engineering an affinity tag for genetically encoded cyclic peptides.
abstract: Peptide expression libraries are valuable probes of cellular function. SICLOPPS technology merges the principal advantages of both genetic methods and small-molecule approaches in yielding superior library sizes of operationally stable, structurally well-defined entities with an established biological and medicinal record. Here, we describe development, application, and the first-generation library implementation of an expressed affinity tag for a library of cyclic peptides. A tripeptide streptavidin-binding motif (HPQ) proved to be compatible with presentation from a backbone cyclized template. A resulting peptide was employed as a sensitive indicator of peptide splicing, expression, and recovery as well as an affinity tag for one-step purification. Specific recognition of the tag by streptavidin was also critical for an analysis of intein mutants. Finally, the initially identified probe was used as a template for design of a streptavidin-responsive cyclic peptide library.
authors.affiliation: Department of Chemistry, The Pennsylvania State University, 414 Wartik Laboratory, University Park, PA 16802, USA.
authors.forename: Todd A
authors.initials: TA
authors.lastname: Naumann
authors.forename: Sergey N
authors.initials: SN
authors.lastname: Savinov
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Benkovic
mesh_terms: D020816:Amino Acid Motifs / Q000235:genetics; D047668:Inteins / Q000235:genetics*; D019151:Peptide Library; D010456:Peptides, Cyclic / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011485:Protein Binding; D015202:Protein Engineering; D019809:Streptavidin / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D019151:Peptide Library; D010456:Peptides, Cyclic; D019809:Streptavidin