Bacteriophage library

Screening methodologies for kinase inhibitors have been revolutionized in their breadth with the advent of bacteriophage libraries of kinase display [6], enabling... 

Fig. 8.5 High-throughput screening at 10mMforWBZ 4 (red) andimatinib (STI 571, blue, control) over a battery of human kinases displayed in a T7-bacteriophage library (Ambit Biosciences, San Diego, CA). Hit values are reported as percentage-bound kinase. Reprinted from the [14], copyright 2007 with permission from the American Society for Clinical Investigation...

As shown in Chap. 8, WBZ 4 is a re-engineered version of imatinib with an enhanced specificity needed to curb imatinib s potential cardiotoxicity. The inhibitory impact of WBZ 4 is restricted to KIT, PDGFR, and JNK, all with nanomolar affinity, as corroborated by screening against a T7-bacteriophage library of kinase displays (Ambit Biosciences, CA) [13],... 

Expression vectors are engineered so that any cloned insert can be transcribed into RNA, and, in many instances, even translated into protein. cDNA expression libraries can be constructed in specially designed vectors derived from either plasmids or bacteriophage A. Proteins encoded by the various cDNA clones within such expression libraries can be synthesized in the host cells, and if suitable assays are available to identify a particular protein, its corresponding cDNA clone can be identified and isolated. Expression vectors designed for RNA expression or protein expression, or both, are available. 

Yeast (Saeeharomyees eerevisiae) has a genome size of 1.21 X 10 bp. If a genomic library of yeast DNA was constructed in a bacteriophage A vector capable of carrying 16-kbp inserts, how many indi-... 

Library A collection of antibodies, usually Fab or scFv fragments, in the range of 106 to 1010 and displayed on the surface of bacteriophage whose DNA gene contains a DNA sequence capable of expression as the antibody protein. Thus, identification of a single member of the library by selection can be used to generate multiple copies of the phage and sizeable amounts of the antibody protein. 

FIGURE 6.3 Construction of a brain-specific cDNA library. Messages (mRNA) are isolated from a tissue of interest. In this case, the target tissue is the brain. The mRNAs are converted to cDNA and each cDNA is inserted into the DNA of the bacteriophage lambda. The end result is a brain-specific cDNA library. 

The next step is to screen the library for the insert of interest (Fig. 6.4). The bacteriophages are mixed with bacteria at the appropriate concentration such that each bacteriophage will infect a single bacteria. The progeny will infect adjacent bacteria and repeat the process of infection, replication and bursting until... 

XEMBL3A Bacteriophage E. coli Genomic library construction. Reduced chance of escape from laboratory biological containment... 

To circumvent some of the limitations of direct immunization, phage display technology has been applied to the preparation of fully human MABs. Gene libraries of cDNA from nonimmune or immunized donor lymphocytes are expressed in bacteriophages. The bacteriophages display functional antibody fragments and can... 

One type of expression library is created by insertion of the cDNAs into copies of a bacteriophage gene that permits the expressed proteins to be displayed on surfaces of the phages1863 (see Fig. 3-16). 

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