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  • Quantum Cascade Laser Infrared Microscopy and 2D IR Correlation Spectroscopy Improves Crystallization Screening of a Protein Complex
Title: Quantum Cascade Laser Infrared Microscopy and 2D IR Correlation Spectroscopy Improves Crystallization Screening of a Protein Complex
X-ray diffraction of crystallized protein continues to be the preferred means of obtaining high-resolution structures of proteins and their complexes. These structures are crucial for drug design, but the screening and optimization of the conditions that produce well-diffracting crystals represent a bottleneck in the structure determination process. In this study, a quantum cascade laser (QCL) infrared microscope was used to determine protein aggregation, distinct from self-association, which is crucial to the success of any crystallization effort. Hyperspectral images of an aliquot from a vapor diffusion hanging drop crystallization screen were acquired over a small temperature range (30–38 ºC), at intervals of 2 ºC. QCL infrared (IR) spectral data were subjected to 2D IR correlation analysis to describe Homo sapiens (Hs) centrin 2(E32A)-Sfi1p21 complex (1:1.5 molar ratio) and the selective aggregation of the target peptide. To our knowledge, this is the first time such a level of molecular understanding has been achieved.  more » « less
Award ID(s):
1632420
PAR ID:
10199415
Author(s) / Creator(s):
;
Editor(s):
Bush, L; Workman, J.
Date Published:
Journal Name:
Spectroscopy
Volume:
34
Issue:
11
ISSN:
0887-6703
Page Range / eLocation ID:
34 - 39
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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