FIGURE 2.

Demonstration of the effects of H/D exchange of backbone amides of the molten globule of flavodoxin. a, HSQC spectrum of Tyr⁴⁴-flavodoxin in D₂O. b, HSQC spectrum of the Tyr⁴⁴-flavodoxin sample obtained from an interrupted H/D exchange experiment during which the molten globule of flavodoxin was allowed to exchange its amide protons for solvent deuterons for a period of 2 min (see “Experimental Procedures”).