Biological Applications of Crystallography
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Biological Applications of Crystallography Joseph D. Ng University of Alabama in Huntsville May 24, 2014 www.uah.edu/nglab
description
Biological Applications of Crystallography. Joseph D. Ng. University of Alabama in Huntsville May 24, 2014. www.uah.edu/nglab. Crystallography is NOT… …. 34Å. All you need to know…for now. sin a = y/h. h. y. cos a = x/h. tan a = y/x. a. a= tan -1 (y/x). x. Bragg ’ s Law. 72 o. - PowerPoint PPT Presentation
Transcript of Biological Applications of Crystallography
Biological Applications of Crystallography
Joseph D. Ng
University of Alabama in HuntsvilleMay 24, 2014
www.uah.edu/nglab
Crystallography is NOT……
34Å
y
x
h
sin = y/h
cos = x/h
tan = y/x
Bragg’s Law
All you need to know…for now
tan-1(y/x)
72o
2.8mm
y
x
h
tan-1(y/x) = 3.2
X-ray
Film
x
x=50mm
y=2.8mm
Bragg’s Law
d= 27.5Å
Let’s calculate Pitch
cos = x/h cos = d/P P=d/cos
P= 34Å
72o
2.8mm
y=Rsiny=Rsin(x/P)
dy/dx=Rcos(x/P)/P
So when x=0
dy/dx = R/P
dy/dx =Rcos()/P
X=0Tan (90o-)= R/P
Let’s calculate Radius!
X=0
R = 10Å
34Å
Hydrogen-bonding patters in the base pairs defined by Watson and Crick
Sample of Crystals Obtained
Advanced Photon Source Argonne National Lab
2.0 Å