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91.
92.
C. Wong Po Foo E. Bini J. Huang S.Y. Lee D.L. Kaplan 《Applied Physics A: Materials Science & Processing》2006,82(2):193-203
Spider dragline silk from Nephila clavipes possesses impressive mechanical properties derived in part from repetitive primary sequence containing polyalanine regions
that self-assemble into crystalline β-sheets. In the present study, we have sought to understand more details of redox responses
related to conformational transitions of modified silk peptides and a recombinant protein containing encoded methionine triggers.
Regardless of the position of the methionine trigger relative to the polyalanine domain, chemical oxidation was rapid and
slight increases in the α-helical structure and decreases in the β-sheet and random coil content were observed by CD and FTIR
in the assembled silk-like peptides and the recombinant protein. CD results indicated that the decrease in β-sheet and random
coil conformations, coupled with the increase in helical content during oxidation, occurred during the first 30 min of the
reaction. No further conformational changes occurred after this time and the response was independent of methionine trigger
location relative to the penta-alanine domain. These results were confirmed with fluorescence studies. The design, processing
and utility of these modified redox triggered silk-like peptides and proteins suggest a range of potential utility, from biomaterials
to engineered surface coatings with chemically alterable secondary structure and, thus, properties.
PACS 87.14.Ee; 87.64.-t; 87.6.+2. 相似文献
93.
F. M. Schertz S. Rask E. Kaplan H. C. Waterman und T. L. Mc Namara 《Fresenius' Journal of Analytical Chemistry》1936,107(1-2):44
Ohne Zusammenfassung 相似文献
94.
A. Miller D. A. B. Miller M. Bensoussan J. M. Moison D. C. Haueisen D. A. Depatie P. W. Kruse M. A. Khan A. L. Smirl B. S. Wherrett T. F. Boggess G. P. Perryman D. S. Chemla P. W. Smith A. C. Gossard W. T. Tsang S. Chu P. Hu T. M. Jedju S. Y. Yuen P. A. Wolff V. Moloney F. A. Hopf H. M. Gibbs S. L. McCall D. L. Kaplan S. Ovadia J. V. Moloney D. F. Walls 《Applied physics. B, Lasers and optics》1982,28(2-3):92-101
95.
96.
97.
98.
Zhongping Chen D. L. Kaplan K. Yang J. Kumar K. A. Marx S. K. Tripathy 《Journal of Sol-Gel Science and Technology》1996,7(1-2):99-108
Light transducing phycobiliproteins are encapsulated in optically transparent sol-gel matrices. Absorption and fluorescence spectroscopies are used to characterize the effect of the sol-gel encapsulation on the conformation and aggregation states of the three major phycobiliproteins present in phycobilisomes: phycoerythrin, phycocyanin, and allophycocyanin. It is found that the effects of sol-gel entrapment on the spectroscopic properties are significantly different for the three phycobiliproteins. The results indicate that phycoerythrin undergoes only minor change in its native structure when entrapped in sol-gel. However, significant changes in conformation and aggregation state occur when phycocyanin and allophycocyanin are entrapped in sol-gel matrices. A thin film of sol-gel encapsulated phycoerythrin is also coated on an optical fiber surface and strong fluorescence from the evanescent wave excitation is detected. The potential applications of sol-gel encapsulated phycobiliproteins in biosensors are discussed. 相似文献
99.
The relative gas phase proton affinities for an amide, ester, and thiolester have been established as CH3CONHCH3 > CH3COSCH3 > CH3COOCH3 using ion cyclotron resonance techniques. A dithioester is more basic than the thiolester: CH3CSSCH3 > CH3COSCH3. d-Orbitals are unimportant in the electronic structure of thiolesters. 相似文献
100.