The quaternary structure of insulin glargine and glulisine under formulation conditions.

Nagel N, Graewert MA, Gao M, Heyse W, Jeffries CM, Svergun D, Berchtold H, Biophys Chem 253:106226 (2019) Europe PMC

SASDF94 – Insulin glulisine (Apidra), oligomeric composition

Insulin glulisine
MWI(0) 34 kDa
MWexpected 35 kDa
log I(s) 6.25×104 6.25×103 6.25×102 6.25×101
Insulin glulisine small angle scattering data  s, nm-1
ln I(s)
Insulin glulisine Guinier plot ln 6.25×104 Rg: 2.3 nm 0 (2.3 nm)-2 s2
(sRg)2I(s)/I(0)
Insulin glulisine Kratky plot 1.104 0 3 sRg
p(r)
Insulin glulisine pair distance distribution function Rg: 2.3 nm 0 Dmax: 7.6 nm

Data validation


Fits and models


log I(s)
 s, nm-1
Insulin glulisine CUSTOM IN-HOUSE model
Insulin glulisine CUSTOM IN-HOUSE model
Insulin glulisine CUSTOM IN-HOUSE model
Insulin glulisine PDB (PROTEIN DATA BANK) model

log I(s)
 s, nm-1

log I(s)
 s, nm-1

Synchrotron SAXS data from solutions of Insulin glulisine (Apidra), oligomeric composition in Apidra formulation (per ml: 5 mg Sodium chloride, 3.15 mg m-Cresol, 6 mg Trometamol, 0.01 mg Polysorbate 20), pH 7.3 were collected on the EMBL P12 beam line at the PETRA III storage ring (Hamburg, Germany) using a Pilatus 2M detector at a sample-detector distance of 3.1 m and at a wavelength of λ = 0.1241 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). One solute concentration of 3.49 mg/ml was measured at 20°C. 20 successive 0.045 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.

Here, Apidra measured at 3.49 mg/ml is displayed (formulation concentration). Measurements from 2 dilutions in placebo have been deposited in addition. Mixture analysis of the scattering profiles was performed with the program Oligomer. The SAXS data show that Apidra® primarily consists of hexamers, which dissociate into monomers upon dilution. The presence of dimers was not required to fit the experimental data, and their volume fraction was always essentially zero. A small volume fraction is, however, also made up by larger dodecameric species. The distribution between monomer, dimer, hexamer and dodecamer is documented in the logfile. Calculation of the form factors is based on an internal model (Apidra.pdb) for hexamers and 3W80.pdb for dodecamers.

Insulin glulisine
Mol. type   Protein
Olig. state   Hexamer
Mon. MW   5.8 kDa
Sequence   FASTA
 
PDB ID   3W80