Selecting phage

A. nidulans with selected phages of classes A, B, C, D and E resulted in increased polygalacturonase activity in comparison with the wild type strain. The culture media of pga transformants were further analysed by Western blotting with polyclonal antibodies raised against PGI and in all samples examined cross-reactive bands with molecular masses similar to that found for PGI or PGII were detected. 

The diversity of the selected phage MAb may be assessed by gel electrophoresis of PCR products (15,18), probing (52), or by sequencing of the vector DNA (whether as phage, phagemid, or plasmid). 

Fig. 6.1. Summary of methods for selecting phage-displayed enzymes on die basis of catalytic activity (S substrate P product SS suicide substrate Bt biotin SV streptavidin TSA transition state analogue).

A constant out/in ratio could mean that no clones are being selected. For some strategies that require low-affinity capture for selection, the level of specifically captured phages might always be below the background level. It is therefore worth analyzing the selected phages, because effective enrichment may have occurred. 

If there is only one copy of each type of phage before selection, p(f) is of the form shown in Fig. 8a. Here, either the best ligand is not selected and its mole fraction is 0, or it is selected and its mole fraction is 1 divided by the total number of selected phage. p(f) thus consists of a spike of value p(L,sel= 0) at f =0 and a hump centered about l/( 1 + psd), where here psd does not include ligand i. When there are several copies of phage i, p(f) consists... 

Malmborg A-C, Soderlind E, Frost L, Borrebaeck CAK, Selective phage infection mediated by epitope expression on F pilus, J. Mol. Biol., 273 544-551, 1997. 

To rescue the selected phage, infect a TOPI OF culture (OD60o = 0.5) by the output phages from the selection (30 min, 37°C), spin down the cells, and resuspend in 1 mL of the supernatant. Plate the cell suspension on agar plates (amp/tet) and incubate at 37°C overnight. 

Analyze binding of selected phage clones by flow cytometry. 

Selecting Phage from tiie X8 Library Against PSMA... 

Inhibition of Selected Phage Clone by Cognate Peptide (Outlined in Subheading 3.14)... 

Selected phage clone and corresponding synthetic peptide. 

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