Force measurements of the disruption of the nascent polypeptide chain from the ribosome by optical tweezers

► We prepared a cell free system to observe polypeptide chain folding at the ribosome. ► We use optical tweezers to pull nascent polypeptide chains out of the ribosome. ► We observe specific hook-ups to the nascent chain by dsDNA handles. ► A rupture force of 10-50 pN was measured. ► At lower forces the system is stable over a long period of time.