Structural highlights
Publication Abstract from PubMed
The polymorphism of human insulin upon pH variation was characterized via X-ray powder diffraction, employing a crystallization protocol previously established for co-crystallization with phenolic derivatives. Two distinct rhombohedral (R3) polymorphs and one cubic (I2(1)3) polymorph were identified with increasing pH, corresponding to the T(6), T(3)R(3)(f) and T(2) conformations of insulin, respectively. The structure of the cubic T(2) polymorph was determined via multi-profile stereochemically restrained Rietveld refinement at 2.7 A resolution. This constitutes the first cubic insulin structure to be determined from crystals grown in the presence of zinc ions, although no zinc binding was observed. The differences of the polycrystalline variant from other cubic insulin structures, as well as the nature of the pH-driven phase transitions, are discussed in detail.
The T(2) structure of polycrystalline cubic human insulin.,Triandafillidis DP, Karavassili F, Spiliopoulou M, Valmas A, Athanasiadou M, Nikolaras G, Fili S, Kontou P, Bowler MW, Chasapis CT, Von Dreele RB, Fitch AN, Margiolaki I Acta Crystallogr D Struct Biol. 2023 May 1;79(Pt 5):374-386. doi: , 10.1107/S2059798323001328. Epub 2023 Apr 11. PMID:37039669[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Triandafillidis DP, Karavassili F, Spiliopoulou M, Valmas A, Athanasiadou M, Nikolaras G, Fili S, Kontou P, Bowler MW, Chasapis CT, Von Dreele RB, Fitch AN, Margiolaki I. The T(2) structure of polycrystalline cubic human insulin. Acta Crystallogr D Struct Biol. 2023 May 1;79(Pt 5):374-386. PMID:37039669 doi:10.1107/S2059798323001328