In bacteria, the movement of RNA polymerase synthesizing mRNA is coordinated with the movement of the ribosome translating mRNA, creating a transcription-translation complex. Structural information acquired at PNCC reveals two new transcription-translation states based on different lengths of mRNA spacers between RNA polymerase the ribosome’s active center p-site. Citation: "Structural basis of transcription-translation coupling" Chengyuan Wang, Vadim Molodtsov, Emre Firlar, Jason Kaelber, Gregor Blaha, Min Su, and Richard H. Ebright. (2020)