9QLD
Rhombohedral crystalline form of human insulin complexed with m-nitrophenol
Summary for 9QLD
| Entry DOI | 10.2210/pdb9qld/pdb |
| Descriptor | Insulin A chain, Insulin B chain, 3-nitrophenol, ... (7 entities in total) |
| Functional Keywords | insulin complex, m-nitrophenol, rhombohedral, hi, hormone |
| Biological source | Homo sapiens (human) More |
| Total number of polymer chains | 4 |
| Total formula weight | 12161.46 |
| Authors | Papaefthymiou, C.,Nanao, M.H.,Margiolaki, I.,Kontarinis, A.,Kafetzi, S.,Konstantopoulos, M.,Koutoulas, D. (deposition date: 2025-03-20, release date: 2025-10-29, Last modification date: 2026-01-28) |
| Primary citation | Kontarinis, A.,Papaefthymiou, C.,Kafetzi, S.,Konstantopoulos, M.,Koutoulas, D.,Nanao, M.,Schluckebier, G.,Norrman, M.,Dadivanyan, N.,Beckers, D.,Degen, T.,Rosmaraki, E.,Fitch, A.,Margiolaki, I. Exploring humidity effects on polycrystalline human insulin-ligand complexes: preliminary crystallographic insights. J.Appl.Crystallogr., 58:1920-1935, 2025 Cited by PubMed Abstract: This study investigates the effect of relative humidity (RH) on the crystal structures of human insulin (HI) complexes with organic ligands, -cresol and -nitro-phenol, using X-ray powder diffraction (XRPD) with a controlled-humidity chamber. Co-crystallization at pH 7.5 produced hexagonal microcrystals (space group 3) for both protein-ligand complexes. The corresponding single-crystal X-ray diffraction structures were solved: HI--cresol (PDB entry 9ibb, 1.84 Å) and HI--nitro-phenol (PDB entry 9qld, 2.55 Å). Pawley analysis of the XRPD data revealed structural stability up to 70% RH, with no phase transitions observed. At lower humidity levels, reduced diffraction intensities indicated loss of crystallinity, which was fully restored upon rehydration to 95% RH. Notably, each complex exhibited distinct changes in unit-cell parameters during dehydration-rehydration cycles. These results highlight the critical role of controlling environmental factors in structure-based drug design and pharmaceutical manufacturing, and demonstrate how organic ligands can enhance the stability of protein crystals, offering valuable insights for pharmaceutical development. PubMed: 41551492DOI: 10.1107/S1600576725007484 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (2.55 Å) |
Structure validation
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