[6][7][8][9][10][11][12] Recently Porter et al. published a revised structure of TGT based on extensive 2D NMR data.

In vitro, TGT inhibits bacterial RNAPs from Escherichia coli and Thermus thermophilus, and eukaryotic RNA polymerase III.

TGT binds in the RNAP active site[16] and inhibits initiation and elongation phases of transcription as well as pyrophosphorolysis of the nascent RNA.

[17][18] It has been suggested that TGT forms a ternary RNAP-NTP-TGT complex and inhibits phosphodiester bond synthesis either by binding an inhibitory magnesium ion[16] or by trapping a flexible active site domain in an inactive conformation.

[19] The third theory suggests that TGT forms predominantly a binary RNAP-TGT complex and inhibits RNAP translocation along the DNA by mimicking the transcription byproduct pyrophosphate.