 Similar to other ribonucleases such as barnase and RNase A, ribonuclease T1 has been popular for folding studies.Structurally, ribonuclease T1 is a small α+β protein (104 amino acids) with a four-stranded, antiparallel beta sheet covering a long alpha helix (almost five turns).RNase T1 has two disulfide bonds, Cys2-Cys10 and Cys6-Cys103, of which the latter contributes more to its folding stability; complete reduction of both disulfides usually unfolds the protein, although its folding can be rescued with high salt concentrations.