5ems: Difference between revisions
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==Crystal Structure of an iodinated insulin analog== | |||
<StructureSection load='5ems' size='340' side='right'caption='[[5ems]], [[Resolution|resolution]] 2.30Å' scene=''> | |||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[5ems]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5EMS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5EMS FirstGlance]. <br> | |||
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.3Å</td></tr> | |||
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=IPH:PHENOL'>IPH</scene>, <scene name='pdbligand=IYR:3-IODO-TYROSINE'>IYR</scene>, <scene name='pdbligand=NLE:NORLEUCINE'>NLE</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=5ems FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5ems OCA], [https://pdbe.org/5ems PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5ems RCSB], [https://www.ebi.ac.uk/pdbsum/5ems PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5ems ProSAT]</span></td></tr> | |||
</table> | |||
== Disease == | |||
[https://www.uniprot.org/uniprot/INS_HUMAN INS_HUMAN] Defects in INS are the cause of familial hyperproinsulinemia (FHPRI) [MIM:[https://omim.org/entry/176730 176730].<ref>PMID:3470784</ref> <ref>PMID:2196279</ref> <ref>PMID:4019786</ref> <ref>PMID:1601997</ref> Defects in INS are a cause of diabetes mellitus insulin-dependent type 2 (IDDM2) [MIM:[https://omim.org/entry/125852 125852]. IDDM2 is a multifactorial disorder of glucose homeostasis that is characterized by susceptibility to ketoacidosis in the absence of insulin therapy. Clinical fetaures are polydipsia, polyphagia and polyuria which result from hyperglycemia-induced osmotic diuresis and secondary thirst. These derangements result in long-term complications that affect the eyes, kidneys, nerves, and blood vessels.<ref>PMID:18192540</ref> Defects in INS are a cause of diabetes mellitus permanent neonatal (PNDM) [MIM:[https://omim.org/entry/606176 606176]. PNDM is a rare form of diabetes distinct from childhood-onset autoimmune diabetes mellitus type 1. It is characterized by insulin-requiring hyperglycemia that is diagnosed within the first months of life. Permanent neonatal diabetes requires lifelong therapy.<ref>PMID:17855560</ref> <ref>PMID:18162506</ref> Defects in INS are a cause of maturity-onset diabetes of the young type 10 (MODY10) [MIM:[https://omim.org/entry/613370 613370]. MODY10 is a form of diabetes that is characterized by an autosomal dominant mode of inheritance, onset in childhood or early adulthood (usually before 25 years of age), a primary defect in insulin secretion and frequent insulin-independence at the beginning of the disease.<ref>PMID:18192540</ref> <ref>PMID:18162506</ref> <ref>PMID:20226046</ref> | |||
== Function == | |||
[https://www.uniprot.org/uniprot/INS_HUMAN INS_HUMAN] Insulin decreases blood glucose concentration. It increases cell permeability to monosaccharides, amino acids and fatty acids. It accelerates glycolysis, the pentose phosphate cycle, and glycogen synthesis in liver. | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Insulin, a protein critical for metabolic homeostasis, provides a classical model for protein design with application to human health. Recent efforts to improve its pharmaceutical formulation demonstrated that iodination of a conserved tyrosine (TyrB26) enhances key properties of a rapid-acting clinical analog. Moreover, the broad utility of halogens in medicinal chemistry has motivated use of hybrid quantum- and molecular-mechanical methods to study proteins. Here, we (i) undertook quantitative atomic-level simulations of 3-I-TyrB26-insulin to predict its structural features and (ii) tested these predictions by X-ray crystallography. Using an electrostatic model of the modified aromatic ring based on quantum chemistry, the calculations suggested that the analog - as a dimer and hexamer - exhibits subtle differences in aromatic-aromatic interactions at the dimer interface. Aromatic rings at this interface (TyrB16, PheB24, PheB25, 3-I-TyrB26 and their symmetry-related mates) adjust to enable packing of the hydrophobic iodine atoms within the core of each monomer. Strikingly, these features were observed in the crystal structure of a 3-iodo-TyrB26 insulin analog (determined as an R6 zinc hexamer). Given that residues B24-B30 detach from the core on receptor binding, the environment of 3-I-TyrB26 in a receptor complex must differ from that in the free hormone. Based on the recent structure of a "micro-receptor" complex, we predict that 3-I-TyrB26 engages the receptor via directional halogen bonding and halogen-directed hydrogen bonding: favorable electrostatic interactions exploiting, respectively, the halogen's electron-deficient sigma-hole and electronegative equatorial band. Inspired by quantum chemistry and molecular dynamics, such "halogen engineering" promises to extend principles of medicinal chemistry to proteins. | |||
Extending Halogen-Based Medicinal Chemistry to Proteins: Iodo-Insulin as a Case Study.,El Hage K, Pandyarajan V, Phillips NB, Smith BJ, Menting JG, Whittaker J, Lawrence MC, Meuwly M, Weiss MA J Biol Chem. 2016 Nov 14. pii: jbc.M116.761015. PMID:27875310<ref>PMID:27875310</ref> | |||
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | |||
[[ | </div> | ||
[[Category: | <div class="pdbe-citations 5ems" style="background-color:#fffaf0;"></div> | ||
[[Category: | |||
[[Category: Lawrence | ==See Also== | ||
[[Category: Pandyarajan | *[[Insulin 3D Structures|Insulin 3D Structures]] | ||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Homo sapiens]] | |||
[[Category: Large Structures]] | |||
[[Category: Lawrence MC]] | |||
[[Category: Pandyarajan V]] | |||
[[Category: Wan Z]] | |||
[[Category: Weiss MA]] |
Latest revision as of 11:07, 12 July 2023
Crystal Structure of an iodinated insulin analogCrystal Structure of an iodinated insulin analog
Structural highlights
DiseaseINS_HUMAN Defects in INS are the cause of familial hyperproinsulinemia (FHPRI) [MIM:176730.[1] [2] [3] [4] Defects in INS are a cause of diabetes mellitus insulin-dependent type 2 (IDDM2) [MIM:125852. IDDM2 is a multifactorial disorder of glucose homeostasis that is characterized by susceptibility to ketoacidosis in the absence of insulin therapy. Clinical fetaures are polydipsia, polyphagia and polyuria which result from hyperglycemia-induced osmotic diuresis and secondary thirst. These derangements result in long-term complications that affect the eyes, kidneys, nerves, and blood vessels.[5] Defects in INS are a cause of diabetes mellitus permanent neonatal (PNDM) [MIM:606176. PNDM is a rare form of diabetes distinct from childhood-onset autoimmune diabetes mellitus type 1. It is characterized by insulin-requiring hyperglycemia that is diagnosed within the first months of life. Permanent neonatal diabetes requires lifelong therapy.[6] [7] Defects in INS are a cause of maturity-onset diabetes of the young type 10 (MODY10) [MIM:613370. MODY10 is a form of diabetes that is characterized by an autosomal dominant mode of inheritance, onset in childhood or early adulthood (usually before 25 years of age), a primary defect in insulin secretion and frequent insulin-independence at the beginning of the disease.[8] [9] [10] FunctionINS_HUMAN Insulin decreases blood glucose concentration. It increases cell permeability to monosaccharides, amino acids and fatty acids. It accelerates glycolysis, the pentose phosphate cycle, and glycogen synthesis in liver. Publication Abstract from PubMedInsulin, a protein critical for metabolic homeostasis, provides a classical model for protein design with application to human health. Recent efforts to improve its pharmaceutical formulation demonstrated that iodination of a conserved tyrosine (TyrB26) enhances key properties of a rapid-acting clinical analog. Moreover, the broad utility of halogens in medicinal chemistry has motivated use of hybrid quantum- and molecular-mechanical methods to study proteins. Here, we (i) undertook quantitative atomic-level simulations of 3-I-TyrB26-insulin to predict its structural features and (ii) tested these predictions by X-ray crystallography. Using an electrostatic model of the modified aromatic ring based on quantum chemistry, the calculations suggested that the analog - as a dimer and hexamer - exhibits subtle differences in aromatic-aromatic interactions at the dimer interface. Aromatic rings at this interface (TyrB16, PheB24, PheB25, 3-I-TyrB26 and their symmetry-related mates) adjust to enable packing of the hydrophobic iodine atoms within the core of each monomer. Strikingly, these features were observed in the crystal structure of a 3-iodo-TyrB26 insulin analog (determined as an R6 zinc hexamer). Given that residues B24-B30 detach from the core on receptor binding, the environment of 3-I-TyrB26 in a receptor complex must differ from that in the free hormone. Based on the recent structure of a "micro-receptor" complex, we predict that 3-I-TyrB26 engages the receptor via directional halogen bonding and halogen-directed hydrogen bonding: favorable electrostatic interactions exploiting, respectively, the halogen's electron-deficient sigma-hole and electronegative equatorial band. Inspired by quantum chemistry and molecular dynamics, such "halogen engineering" promises to extend principles of medicinal chemistry to proteins. Extending Halogen-Based Medicinal Chemistry to Proteins: Iodo-Insulin as a Case Study.,El Hage K, Pandyarajan V, Phillips NB, Smith BJ, Menting JG, Whittaker J, Lawrence MC, Meuwly M, Weiss MA J Biol Chem. 2016 Nov 14. pii: jbc.M116.761015. PMID:27875310[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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