High torsional energy disulfides: relationship between cross-strand disulfides and right-handed staples.
Redox-active disulfides are capable of being oxidized and reduced under physiological conditions. The enzymatic role of redox-active disulfides in thiol-disulfide reductases is well-known, but redox-active disulfides are also present in non-enzymatic protein structures where they may act as switches of protein function. Here, we examine disulfides linking adjacent beta-strands (cross-strand disulfides), which have been reported to be redox-active. Our previous work has established that these cross-strand disulfides have high torsional energies, a quantity likely to be related to the ease with which the disulfide is reduced. We examine the relationship between conformations of disulfides and their location in protein secondary structures. By identifying the overlap between cross-strand disulfides and various conformations, we wish to address whether the high torsional energy of a cross-strand disulfide is sufficient to confer redox activity or whether other factors, such as the presence of the cross-strand disulfide in a strained beta-sheet, are required.
Haworth
Naomi L
NL
Computational Biology & Bioinformatics Program, Victor Chang Cardiac Research Institute, Level 6, 384 Victoria Rd, Darlinghurst, New South Wales 2010, Australia. n.haworth@victorchang.unsw.edu.au
Feng
Lina L
LL
Wouters
Merridee A
MA
D019295:Computational Biology; D003198:Computer Simulation; D004220:Disulfides / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D010084:Oxidation-Reduction; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism*; D013816:Thermodynamics
D004220:Disulfides; D011506:Proteins