Specific peptide binders to proteins identified via systematic discovery, maturation and extension process

An isolated artificial peptide binder bound to a target protein, the isolated artificial peptide binder having specific affinity for the target protein, the artificial peptide binder having at least 5 and up to 20 amino acids, the artificial peptide binder selected from a streptavidin binder comprising a sequence selected from the sequences in Tables 1 and 2;

• a Taq polymerase binder comprising a sequence selected from the sequences in Table 3;
• a binder to Prostate Specific Antigen (PSA) comprising a sequence selected from the sequences in Table 4;
• a thrombin binder comprising a sequence selected from the sequences in Table 5;
• a binder to Tumor Necrosis Factor comprising a sequence selected from the sequences in Table 6;
• and a binder to Urokinase-type Plasminogen Activator (uPA) comprising a sequence selected from the sequences in Table 7,
• wherein the artificial peptide binder is one of an N-terminal tag added to a protein, a C-terminal tag added to a protein, and attached to a solid support through a covalent bond,
• wherein when the artificial peptide binder is a streptavidin binder, the target protein is streptavidin,
• wherein when the artificial peptide binder is a Taq polymerase binder, the target protein is Taq polymerase,
• wherein when the artificial peptide binder is a Prostate Specific Antigen (PSA) binder, the target protein is Prostate Specific Antigen (PSA),
• wherein when the artificial peptide binder is a thrombin binder, the target protein is thrombin,
• wherein when the artificial peptide binder is a binder to Tumor Necrosis Factor, the target protein is Tumor Necrosis Factor, and
• wherein when the artificial peptide binder is a binder to Urokinase-type Plasminogen Activator (uPA), the target protein is Urokinase-type Plasminogen Activator (uPA).