Fig 1: Binding affinity of artificial promoter constructs to the transcription factors TFIIB and TBP.The binding expressed as Δnm on the y-axis was monitored in real time as sec (x-axis), using the ForteBio Octet QK instrument. Binding was conducted in four phases: (i) loading of biotinylated DNA fragments to the streptavidin biosensor tip, (ii) washing in Kinetics Buffer, (iii) association of the transcription factor and (iii) dissociation of the transcription factor. (a) The promoter constructs ArS110, ArS201, ArS232 and ArS300 show similar binding affinities to the TFIIB protein. (b) The promoter constructs ArS232, ArS232 dT1, ArS232 dT2 and ArS232 dT12 exhibit sequence-specific binding to the TBP protein. ArS232 dT12 lacking two TATA-Boxes shows the lowest binding affinity compared to the other constructs. (c) TFIIB binding vs. a negative control, for which we chose a 85 bp long sequence from inside the coding region of the luciferase gene (pGL3-Basic Promoter Promega: 1314 bp–1399 bp).