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Crystallography 2018
Structural Chemistry & Crystallography Communication
ISSN: 2470-9905
Page 62
June 04-05, 2018
London, UK
3
rd
Edition of International Conference on
Advanced Spectroscopy,
Crystallography and Applications
in Modern Chemistry
S
urfaces with heterogeneous structures facilitate protein
crystallization by diminishing the energy barrier for nucleation.
Nevertheless, a precipitant remains necessary for shielding the
chargesonproteinmolecules, which thenovercomeselectrostatic
repulsion and selfassemble into crystalline structure. For yet-to-
be crystallized proteins, identifying the right precipitant is non-
trivial and therefore, despite existence of several heterogeneous
surfaces, number of such yet-to-be crystallized proteins
continues to be large. In this talk, we will describe a novel surface
decorated with both nanoscopic patterns and surface charges,
the combined effect of which show the remarkable ability to
induce crystallization without use of any precipitant. In fact,
several protein molecules with molecular weight ranging from
14-450 kDa could be crystallized in this process. These surfaces
can induce also crystallization of a specific protein from a
mixture of two or more protein species and even simultaneous
crystallization from a mixture of proteins. Kelvin probe force
microscopy (KPFM) measurements of these surfaces show that
surface potential gradient as high as 140 V/μm are generated on
these surfaces which can drive largescale molecular ordering in
the liquid at the vicinity of the surface. As a result, the surface
itself acts both as a precipitant also as a nucleant. Heterogeneity
allows it to crystallize protein molecules having large range of
radius of gyration, that too at low to moderate concentration of
the protein in respective solutions. The prospect of precipitant-
less crystallization of protein is expected to open up several
possibilities in the areas of disease diagnosis, drug discovery,
drug delivery and protein engineering.
aghatak@iitk.ac.inPRECIPITANT-LESS CRYSTALLIZATION OF PROTEIN MOLECULES INDUCED
BY SUBSTRATE WITH HETEROGENEOUS TOPOGRAPHY AND SURFACE
POTENTIAL GRADIENT
Animangsu Ghatak
and
Anindita Sengupta Ghatak
IIT Kanpur, India
Struct Chem Crystallogr Commun 2018, Volume 4
DOI: 10.21767/2470-9905-C1-006