Hydrogen bonds involving sulfur atoms in proteins

Intrachain hydrogen bonds are a hallmark of globular proteins. Traditionally, these involve oxygen and nitrogen atoms. The electronic structure of sulfur is compatible with hydrogen bond formation as well. We surveyed a set of 85 high‐resolution protein structures in order to evaluate the prevalence and geometry of sulfur‐containing hydrogen bonds. This information should be of interest to experimentalists and theoreticians intersted in protein structure and protein engineering.