Bio-Rad Laboratories has filed a patent for a protein display selection method that separates a protein of interest (POI) library from the display selection system. The method involves forming a covalent bond between the POI and an anchor protein using enzymatic protein ligation or spontaneous covalent bond formation. The patent also includes nucleic acid constructs, host cell systems, and methods for producing the protein display systems. GlobalData’s report on Bio-Rad Laboratories gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on Bio-Rad Laboratories, laboratory automation robots was a key innovation area identified from patents. Bio-Rad Laboratories's grant share as of June 2023 was 1%. Grant share is based on the ratio of number of grants to total number of patents.
Protein display selection method using covalent bond formation
A recently filed patent (Publication Number: US20230193297A1) describes a combination of vectors for genetic engineering purposes. The vectors consist of two genetic constructs, GC1 and GC2, which encode a protein of interest (POI) and an anchor protein, respectively. The constructs are fused together using a tether sequence and a capture sequence, forming a covalent bond when brought into contact with each other. The vectors also contain transcriptional or translational control sequences for expressing the POI and anchor protein. These control sequences include replication origins, promoters, enhancers, repressor binding regions, transcription initiation sites, ribosome binding sites, translation initiation sites, and termination sites for transcription and translation.
The POI can be a wide range of proteins, including antibodies, antibody fragments, enzymes, hormones, interleukins, antigens for vaccine development, growth factors, and viral antigens, among others. The tether sequence can be a SpyTag sequence, a SnoopTag sequence, a sortase recognition domain, a sortase bridging domain, a butelase recognition motif, or a split intein. The capture sequence can be a SpyCatcher sequence, a SnoopCatcher sequence, a sortase recognition domain, a sortase bridging domain, a butelase recognition motif, or a split intein.
The patent also covers the use of these vectors in prokaryotic or eukaryotic host cells. The host cells can be modified to express the vectors and display the POI on their surface. The anchor protein can be selected from various proteins, such as pIII, pVI, pVII, pVIII, or pIX in bacteriophages, or outer membrane proteins, pili, flagella, modified lipoproteins, or surface receptors in prokaryotic or eukaryotic cells.
Furthermore, the patent describes methods for displaying the POI on the surface of bacteriophage particles or prokaryotic or eukaryotic cells. These methods involve the attachment of the POI to the anchor protein through the formation of a peptide bond between the tether sequence and the capture sequence.
In addition, the patent includes a helper phage, such as VCSM13 or M13K07, with modified DNA to express a capture sequence-anchor sequence fusion protein or a tether sequence-anchor sequence fusion protein. This modified phage can be used to infect prokaryotic cells and produce phage particles that carry the capture or tether sequence on their surface.
Overall, this patent provides a comprehensive framework for the design and use of vectors and methods for genetic engineering and protein display in various host cells.