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Figure 14
Sulfur substructures from native SAD analyses. (a) Ribbon diagram of the TorT–TorSS ligand–histidine kinase complex showing the 28 S atoms (yellow) and three sulfate ions (yellow with red O atoms) used to define 1148 ordered protein residues. This structural analysis was performed at 7 keV [f′′(S) = 0.73 electrons]. (b) Cα backbone model of bovine trypsin showing the 16 peaks above 6σ in a Bijvoet difference map. A calcium ion has a peak height of 47σ and the sulfur peaks range from 9.6σ to 18.9σ. The peaks from calcium (Ca2+) and sulfate ([{\rm SO_{4}^{2-}}]) ions and from two methionine S atoms (Met) are labeled. The other 12 peaks are in disulfide-bridged pairs. This structural analysis was performed at 12.7 keV [f′′(S) = 0.235 electrons]. (a) was adapted from Fig. 9(d) of Liu et al. (2013BB125).

IUCrJ
Volume 10| Part 5| September 2023| Pages 521-543
ISSN: 2052-2525
https://doi.org/10.1107/S2052252523006449