Footprinting M. tuberculosis nut RNA. (A) Reactions with RNases T1 (0.1, 0.2, and 0.4 units) and CV1 (10-1,10-2, and 10-3 units) in the region from +30 to +63 with and without 250 nM NusA. AH denotes alkaline hydrolyses ladder and 0 is RNA only. (B) Structure for nucleotides +1 to +63 predicted with the mfold program. Letters in bold indicate positions that were most affected by NusA, and U47 is circled. Regions cut with T1 and CV1 are indicated by triangles and stars, respectively, where the size of the symbol indicates the degree of cleavage.