In situ MicroED structure of IL-5 activated human eosinophil major basic protein-1
5-Gaussian fit: Grosse-Kunstleve RW, Sauter NK, Adams PD: Newsletter of the IUCr Commission on Crystallographic Computing 2004, 3, 22-31.
In situ microED structure of the Eosinophil major basic protein-1
Iterative refinement using phenix.refine and model building in COOT
Harvested from human donor peripheral blood and rested in 1640 RPMI medium supplemented with 0.1% human serum albumin (HSA)
Mature human eosinophil cells were collected and purified from human donor blood. This was followed by eosinophil resting and deposition on EM grids. The cells were then activated by IL-5 for 1 hour prior to grid plunge-freezing. Cryo-FIB milling of individual eosinophil cells was then performed to expose unperturbed cytosolic secretory granules, inside which nanocrystals of the major basic protein-1 were located. MicroED data were collected on these crystals for in situ structure determination.
In situ MicroED structure of the IL-5 activated human eosinophil major basic protein-1
Ten datasets, each with 40 images, were scaled together using XSCALE. The electron dose per image was 0.1 e/A^2.
Pre-vacuum was 1 x 10-3 Pa and the process pressure was 1 Pa
Human MBP-1 derives from a precursor or proform proMBP coded by gene PRG2 in eosinophils. Protein MBP-1 naturally forms intragranular nanocrystals that get disassembled upon activation, including cytokine IL-5.
CRYLLVRSLQTFSQAWFTCRRCYRGNLVSIHNFNINYRIQCSVSALNQGQVWIGGRITGSGRCRRFQWVDGSRWNFAYWA AHQPWSRGGHCVALCTRGGHWRRAHCLRRLPFICSY
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
National Institutes of Health/National Heart, Lung, and Blood Institute (NIH/NHLBI)
Department of Energy (DOE, United States)
structure determined from non-activated eosinophils
structure determined from IL-33-activated eosinophils
Authors state that the chloride ions A301 and B301 modeled could be bromide ions.
Effector, Nanocrystal, In-situ, Intracellular, IMMUNE SYSTEM