Fig. 2

Recombinant peptide chip optimization. a Assessment of best E. coli growth intervals for consistent chip performance. A series of E. coli cells transformed with either Strep-tag constructs or empty vector were imprinted on nitrocellulose, grown thereon for the specified period, then exposed to IPTG, and subsequently lysed. Released peptides were analysed for their interaction with HRP-labeled Streptavidin. b Signal intensities (and so a rough estimation of affinities) between Strep-tagII and Dim12G were evaluated in relation to empty vector control, as indicated. Different peptide spot numbers per single standardized microtiter plate well are compared. c Consistent pin performance and maximal detection sensitivity were assessed by spotting a dilution series of biotinylated test protein. d Steps required for recombinant peptide chip assembly