Insulin analog with additional disulfide bond has increased stability and preserved activity.
Vinther, T.N., Norrman, M., Ribel, U., Huus, K., Schlein, M., Steensgaard, D.B., Pedersen, T.A., Pettersson, I., Ludvigsen, S., Kjeldsen, T., Jensen, K.J., Hubalek, F.(2013) Protein Sci 22: 296-305
- PubMed: 23281053 
- DOI: 10.1002/pro.2211
- Primary Citation of Related Structures:  
4EFX - PubMed Abstract: 
Insulin is a key hormone controlling glucose homeostasis. All known vertebrate insulin analogs have a classical structure with three 100% conserved disulfide bonds that are essential for structural stability and thus the function of insulin. It might be hypothesized that an additional disulfide bond may enhance insulin structural stability which would be highly desirable in a pharmaceutical use ...