PROTON MAGNETIC RELAXATION IN SOLUTIONS OF E COLI RIBOSOMAL RNA CONTAINING MN2+ IONS

A study has been made over a range of temperatures and magnetic field strengths of the spin relaxation of water protons in aqueous solutions of E. coli ribosomal RNA containing Mn2+ ions. The effects of the paramagnetic ions are enhanced in the presence of the RNA. As the temperature falls T1 passes through a minimum value, the magnitude of which is field dependent, and this is attributed to a change in dipolar relaxation mechanism from rotation of the aquocomplex to electron spin relaxation. The relevance of this work is assessed in relation to other work on proton relaxation enhancement in Mn2+-containing solutions of biopolymers. © 1969 Taylor and Francis Group, LLC.