The present invention provides compositions including peptide display scaffolds that present at least one candidate peptide and at least one detectable moiety in at least one of the N-terminal and C-terminal candidate peptide presenting domains that when expressed in a cell are accessible at a surface of the cell outermembrane. In addition, the present invention also provides kits and methods for screening a library of cells presenting the candidate peptides in peptide display scaffolds to identify a ligand for an enzyme.

Described herein are engineered CCCTC-binding factor (CTCF) variants that can bind to mutant CTCF binding sequences and method of using the same.

The present invention provides a method for preparing a modular scaffold that can bind to a target antigen and a method for engineering a bispecific functional agent consisting of an existing polypeptide binder fused at its C-terminus with said modular scaffold.

Provided herein are methods and compositions relating to prostaglandin D2 receptor 2 (DP2 or CRTH2R) libraries having nucleic acids encoding for a scaffold comprising a CRTH2R binding domain. CRTH2R libraries described herein encode for immunoglobulins including antibodies and single domain antibodies. Libraries described herein include variegated libraries comprising nucleic acids each encoding for a predetermined variant of at least one predetermined reference nucleic acid sequence. Further described herein are protein libraries generated when the nucleic acid libraries are translated. Further described herein are cell libraries expressing variegated nucleic acid libraries described herein.

Methods and compositions for bacterial production of pure single-stranded DNA (ssDNA) composed of custom sequence and size have been developed. The methods enable scalability and bio-orthogonality in applications of scaffolded DNA origami, offering one-step purification of large quantities of pure ssDNA amendable for immediate folding of DNA nanoparticles. The methods produce pure ssDNA directly from bacteria. In some embodiments the E. coli helper strain M13cp combined with a phagemid carrying only an f1-origin allows for, without the need for additional purification from contaminating dsDNA. This system is useful for generalized circular ssDNA synthesis, and here is applied to the assembly of DNA nanoparticles folded both in vitro and direct from phage.

The present invention provides methods of selecting a target for a ligand, wherein said ligand comprises a polypeptide comprising at least three reactive groups, separated by at least two loop sequences, and a molecular scaffold which forms covalent bonds with the reactive groups of the polypeptide such that at least two polypeptide loops are formed on the molecular scaffold. The present invention also provides said targets, said ligands and methods for using and manufacturing such.

The present invention relates to a novel method of generating libraries of polynucleotides encoding a framework region and at least one adjacent complementarity determining region (CDR) of an antibody of interest. These libraries are suitable for use in affinity maturation procedures in order to obtain maturated antibodies with improved characteristics compared to the parent antibody.

The present invention generally relates to bacterial polypeptide display systems, libraries using these bacterial display systems, and methods of making and using these systems, including methods for improved display of polypeptides on the extracellular surface of bacteria using circularly permuted transmembrane bacterial polypeptides that have been modified to increase resistance to protease degradation and to enhance polypeptide display characteristics.

Disclosed herein are expression vectors which display a passenger polypeptide on the outer surface of a biological entity. As disclosed herein the displayed passenger polypeptide is capable of interacting or binding with a given ligand. Also disclosed are methods of making and using the expression vectors. N/C terminal fusion expression vectors and methods of making and using are also disclosed.

The present invention is directed to a fusion protein comprising a scaffold protein and a series of two or more epitopes, where the distinct epitopes are recognized by distinct antibodies, and where the series of epitopes forms a detectable protein tag. The present invention further relates to a nucleic acid molecule encoding a nucleic acid sequence encoding the fusion protein, as well as vectors comprising the nucleic acid molecule. Methods of tracking a cell and kits using such vectors are also disclosed.