Increasing the hydrolysis constant of the reactive site upon introduction of an engineered Cys14 Cys39 bond into the ovomucoid third domain from silver pheasant

2011 ◽  
Vol 17 (8) ◽  
pp. 595-600
Author(s):  
Hikaru Hemmi ◽  
Takashi Kumazaki ◽  
Shuichi Kojima ◽  
Takuya Yoshida ◽  
Tadayasu Ohkubo ◽  
...  
Biopolymers ◽  
1990 ◽  
Vol 29 (2) ◽  
pp. 461-467 ◽  
Author(s):  
A. D. Robertson ◽  
G. I. Rhyu ◽  
W. M. Westler ◽  
J. L. Markley

Author(s):  
Gudrun A. Hutchins

In order to optimize the toughening effect of elastomers in engineering polymers, it is necessary to characterize the size, morphology and dispersion of the specific elastomer within the polymer matrix. For unsaturated elastomers such as butadiene or isoprene, staining with osmium tetroxide is a well established procedure. The residual carbon-carbon double bond in these materials is the reactive site and forms a 1,2-dilato complex with the OsO4. Incorporation of osmium tetroxide into the elastomer not only produces sufficient contrast for TEM, but also crosslinks the elastomer sufficiently so that ultramicrotomy can be accomplished at room temperature with minimal distortion.Blends containing saturated elastomers such as butyl acrylate (BA) and ethylene propylene diene monomer (EPDM) cannot be stained directly with OsO4 because effective reaction sites such as C=C or -NH2 are not available in sufficient number. If additional reaction sites can be introduced selectively into the elastomer by a chemical reaction or the absorption of a solvent, a modified, two-step osmium staining procedure is possible.


1989 ◽  
Vol 264 (6) ◽  
pp. 3066-3071
Author(s):  
K Skriver ◽  
E Radziejewska ◽  
J A Silbermann ◽  
V H Donaldson ◽  
S C Bock
Keyword(s):  

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