Silk–Silica Composites
from Genetically Engineered Chimeric Proteins: Materials Properties
Correlate with Silica Condensation Rate and Colloidal Stability of
the Proteins in Aqueous Solution
David
J. Belton
Aneta J. Mieszawska
Heather A. Currie
David
L. Kaplan
Carole C. Perry
10.1021/la205084z.s001
https://acs.figshare.com/articles/journal_contribution/Silk_Silica_Composites_from_Genetically_Engineered_Chimeric_Proteins_Materials_Properties_Correlate_with_Silica_Condensation_Rate_and_Colloidal_Stability_of_the_Proteins_in_Aqueous_Solution/2544241
The aim of the study was to determine the extent and
mechanism of influence on silica condensation that is presented by
a range of known silicifying recombinant chimeras (R5: SSKKSGSYSGSKGSKRRIL;
A1: SGSKGSKRRIL; and Si4–1: MSPHPHPRHHHT and repeats thereof)
attached at the N-terminus end of a 15-mer repeat of the 32 amino
acid consensus sequence of the major ampullate dragline Spindroin
1 (Masp1) <i>Nephila clavipes</i> spider silk sequence ([SGRGGLGGQG
AGAAAAAGGA GQGGYGGLGSQG]<sub>15</sub>X). The influence of the silk/chimera
ratio was explored through the adjustment of the type and number of
silicifying domains (denoted X above), and the results were compared
with their non-chimeric counterparts and the silk from <i>Bombyx
mori</i>. The effect of pH (3–9) on reactivity was also
explored. Optimum conditions for rate and control of silica deposition
were determined, and the solution properties of the silks were explored
to determine their mode(s) of action. For the silica–silk–chimera
materials formed there is a relationship between the solution properties
of the chimeric proteins (ability to carry charge), the pH of reaction,
and the solid state materials that are generated. The region of colloidal
instability correlates with the pH range observed for morphological
control and coincides with the pH range for the highest silica condensation
rates. With this information it should be possible to predict how
chimeric or chemically modified proteins will affect structure and
morphology of materials produced under controlled conditions and extend
the range of composite materials for a wide spectrum of uses in the
biomedical and technology fields.
2016-02-22 04:05:39
Aqueous SolutionThe aim
AGAAAAAGGA
pH range
material
Silica Condensation Rate
Materials Properties Correlate
SSKKSGSYSGSKGSKRRIL
SGSKGSKRRIL
solution properties
silicifying
acid consensus sequence
MSPHPHPRHHHT
silica condensation rates
Genetically Engineered Chimeric Proteins
influence
GQGGYGGLGSQG
protein
SGRGGLGGQG
ampullate dragline Spindroin 1
chimeric