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ACA_SINBAD_2013.ppt
AcknowledgementsKen Frankel Alastair MacDowell
John Spence Howard PadmoreLBNL Laboratory Directed Research & Development (LDRD)
ALS 8.3.1 creator: Tom Alber PRT head: Jamie Cate
Center for Structure of Membrane ProteinsMembrane Protein Expression Center II
Center for HIV Accessory and Regulatory Complexes
W. M. Keck FoundationPlexxikon, Inc.
M D Anderson CRCUniversity of California Berkeley
University of California San FranciscoNational Science Foundation
University of California Campus-Laboratory Collaboration GrantHenry Wheeler
The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences Division, of the US Department of Energy under contract No. DE-AC02-05CH11231 at Lawrence Berkeley National Laboratory.
Simultaneous
INverse
Beam
Anomalous
Diffraction
SINBAD diffractometer concept
Nucleus
Synthetic light collecting structureh,k,l
-h,-k,-l
Detec
tor Detector
Detec
tor Detector
d = 3.5 Å d = 3.5 Å
d = 3.5 Åd = 3.5 Å
sample injector
Mirr
ors
Mirr
ors
d = 3.5 Åλ = 5 Å
XFEL beam
Why SINBAD?
I+ I-
Different crystal volumes
New source of error in SFX
Why SINBAD?
I+ I-
Different crystal orientations
New source of error in SFX
Why SINBAD?
I+ I-
Different beam intensities
New source of error in SFX
Why SINBAD?
I+ I-
Different crystal positions
New source of error in SFX
Why SINBAD?
I+ I-
Different structures (non-isomorphism)
New source of error in SFX
Dynamic range
Why SINBAD?
I+ I-
New source of error in SFX
Why SINBAD?
I+ I-
New source of error in SFX
Problem:How to get I+ and I-both on Ewald sphereat the same time?
ΔIano
Ewald sphere 2
diffracted ra
y
λ*
λ*
θ
1Ewald sphere
λ*
(h,k,l)
diffracted ra
yλ*
θ
d*
Osculating Ewald Spheres
(-h,-k,-l)
d*
SINBAD diffractometer concept
Nucleus
Synthetic light collecting structureh,k,l
-h,-k,-l
Detec
tor Detector
Detec
tor Detector
d = 3.5 Å d = 3.5 Å
d = 3.5 Åd = 3.5 Å
sample injector
Mirr
ors
Mirr
ors
d = 3.5 Åλ = 5 Å
XFEL beam
Tolerances:
Time: ~10% of 100 fs
Distance: 3 μm
Angle: ~1% of mosaicity~100 μRad
Can’t we just use scaling?
Ispot ≈ |F(hkl)|2
Darwin’s Formula
I(hkl) - photons/spot (fully-recorded)
Ibeam - incident (photons/s/m2 )
re - classical electron radius (2.818x10-15 m)
Vxtal - volume of crystal (in m3)
Vcell - volume of unit cell (in m3)
λ - x-ray wavelength (in meters!)
ω - rotation speed (radians/s)
L - Lorentz factor (speed/speed)
P - polarization factor
(1+cos2(2θ) -Pfac∙cos(2Φ)sin2(2θ))/2
A - attenuation factor
exp(-μxtal∙lpath)
F(hkl) - structure amplitude (electrons)
C. G. Darwin (1914)
P A | F(hkl) |2I(hkl) = Ibeam re2
Vxtal
Vcell
λ3 LωVcell
Darwin’s Formula
I(hkl) - photons/spot (fully-recorded)
Ibeam - incident (photons/s/m2 )
re - classical electron radius (2.818x10-15 m)
Vxtal - volume of crystal (in m3)
Vcell - volume of unit cell (in m3)
λ - x-ray wavelength (in meters!)
ω - rotation speed (radians/s)
L - Lorentz factor (speed/speed)
P - polarization factor
(1+cos2(2θ) -Pfac∙cos(2Φ)sin2(2θ))/2
A - attenuation factor
exp(-μxtal∙lpath)
F(hkl) - structure amplitude (electrons)
C. G. Darwin (1914)
P A | F(hkl) |2I(hkl) = Ibeam re2
Vxtal
Vcell
λ3 LωVcell
Darwin’s Formula
I(hkl) - photons/spot (fully-recorded)
Ibeam - incident (photons/s/m2 )
re - classical electron radius (2.818x10-15 m)
Vxtal - volume of crystal (in m3)
Vcell - volume of unit cell (in m3)
λ - x-ray wavelength (in meters!)
ω - rotation speed (radians/s)
L - Lorentz factor (speed/speed)
P - polarization factor
(1+cos2(2θ) -Pfac∙cos(2Φ)sin2(2θ))/2
A - attenuation factor
exp(-μxtal∙lpath)
F(hkl) - structure amplitude (electrons)
C. G. Darwin (1914)
P A | F(hkl) |2I(hkl) = Ibeam re2
Vxtal
Vcell
λ3 LωVcell
Greenhough-Helliwell Formula
ΔΦ - reflecting range (radians)
2η - mosaic spread (radians)
L - Lorentz factor (speed/speed)
θ - Bragg angle
λ - x-ray wavelength
Δλ - wavelength spread
γHV - horizontal and vertical
beam divergence (radians)
Greenhough & Helliwell (1983)
ΔΦ = L sin2θ (2η + Δλ/λ tanθ)
+ ((L2sin22θ - 1)γH2 + γV
2)1/2
Greenhough-Helliwell Formula
ΔΦ - reflecting range (radians)
2η - mosaic spread (radians)
L - Lorentz factor (speed/speed)
θ - Bragg angle
λ - x-ray wavelength
Δλ - wavelength spread
γHV - horizontal and vertical
beam divergence (radians)
Greenhough & Helliwell (1983)
ΔΦ = L sin2θ (2η + Δλ/λ tanθ)
+ ((L2sin22θ - 1)γH2 + γV
2)1/2
Lorentz Factor
Ewald sphere
spin
dle
axi
s
diffracted ra
y
Darwin’s Formula
I(hkl) - photons/spot (fully-recorded)
Ibeam - incident (photons/s/m2 )
re - classical electron radius (2.818x10-15 m)
Vxtal - volume of crystal (in m3)
Vcell - volume of unit cell (in m3)
λ - x-ray wavelength (in meters!)
ω - rotation speed (radians/s)
L - Lorentz factor (speed/speed)
P - polarization factor
(1+cos2(2θ) -Pfac∙cos(2Φ)sin2(2θ))/2
A - attenuation factor
exp(-μxtal∙lpath)
F(hkl) - structure amplitude (electrons)
C. G. Darwin (1914)
P A | F(hkl) |2I(hkl) = Ibeam re2
Vxtal
Vcell
λ3 LωVcell
Integral under curve
-0.1
0.1
0.3
0.5
0.7
0.9
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
inte
nsity
“Full” Spot
Integral under curve
-0.1
0.1
0.3
0.5
0.7
0.9
-2 -1.5 -1 -0.5 0 0.5 1 1.5 2
inte
nsity
Spot on “Still”
What is "partiality"?
100%
What is "partiality"?
50%
What is "partiality"?
50%
What is "partiality"?
90%
What is "partiality"?
15%
What is "partiality"?
1%
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
What is "partiality"?
100% !
What is "partiality"?
90%
What is "partiality"?
80%
What is "partiality"?
50%
What is "partiality"?
20%
Bra
gg, Ja
mes
& B
osa
nquet
(19
21
). P
hilo
s. M
ag. Ser.
6, 4
1, 3
09
–3
37
.
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
F(0,0,0)
Partiality is always 100% !
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
F(0,0,0)
Partiality is always 100% !
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
F(0,0,0)
Partiality is always 100% !
What is “partiality”?
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
F(0,0,0)
Partiality is always 100% !
Why SINBAD?
I+ I-
Different crystal orientations
New source of error in SFX
F(h,k,l)
Ewald sphere
spectral dispersion
λ1*
λ2*
F(0,0,0)
100%
~90%
F(h,k,l)
Ewald sphere
spectral dispersion
λ1*
λ2*
F(0,0,0)
100%
~45%
Ewald sphere
spectral dispersion
λ1*
λ2*
F(0,0,0)
F(h,k,l)
100%
0%
F(h,k,l)
F(0,0,0)
beam divergence
Ewald sphere
diffracted ra
yd*
λ*
λ*
beam divergence
Ewald sphere
λ*
λ*
F(0,0,0)
d*
diffra
cted
ray
Ewald’s “mosaic” picture
F(0,0,0)
mosaic spread
Ewald sphere
diffracted ra
y
λ*
λ* d*
d*
F(h,k,l)
F(0,0,0)
Ewald sphere
diffracted ra
y
λ*
λ*
d*
F(h,k,l)
mosaic spread
F(0,0,0)
mosaic spread
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
F(0,0,0)
Ewald sphere
diffracted ra
y
λ*
λ* d*
F(h,k,l)
mosaic spread
F(0,0,0)
mosaic spread
Ewald sphere
diffracted ra
y
λ*
λ* d*
d*
F(h,k,l)
F(0,0,0)
mosaic spread
Ewald sphere
λ*
d*
F(h,k,l)
F(0,0,0)
mosaic spread
Ewald sphere
diffracted ra
yd*
λ*
λ*
F(h,k,l)
F(0,0,0)
mosaic spread
Ewald sphere
λ*
d*
F(h,k,l)
mosaic spread = 0 º
mosaic spread = 0.1º
mosaic spread = 0.2º
mosaic spread = 0.4º
mosaic spread = 0.6º
mosaic spread = 0.8º
mosaic spread = 1.0º
mosaic spread = 1.5º
mosaic spread = 2.0º
mosaic spread = 2.5º
mosaic spread = 3.2º
mosaic spread = 6.4º
mosaic spread = 12.8º
Ewald’s “mosaic” picture
What isthis stuff?
Darwin’s original picture
“mosaicity” with visible light
10 atoms 0.1 μm
Scattering: line of atoms
50 atoms 0.5 μm100 atoms 1 μm200 atoms 2 μm300 atoms 3 μm400 atoms 4 μm500 atoms 5 μm1000 atoms 10 μm
position on detector (mm)
inte
nsity
(ph
oton
s/S
R/a
tom
)
Scattering: line of atomspe
ak in
tens
ity (
phot
ons/
SR
)
number of atoms in line
“coherence length”
•depends on detector distance !!!•integrated intensity never changes•peak intensity depends on size
10 atoms 0.1 μm
Integral under curve
50 atoms 0.5 μm100 atoms 1 μm200 atoms 2 μm300 atoms 3 μm400 atoms 4 μm500 atoms 5 μm
position on detector (mm)
inte
nsity
(ph
oton
s/S
R/a
tom
)
Spot Intensity
Can’t we just rotate the crystal?
1 μm
1°
100 fs= 90 km/s
9 nm
17.26 km/s (90 km/s)2
0.5 μm= 1.5 x 1015 G = 0.5 nN
Can’t we just rotate the crystal?
NO
Why do we want to rotate the crystal?
The “nanocrystal advantage”
Ispot = k Ncells
Ewald sphererange
2
Fraunhofer Formula
Ipixel - photons/pixel/s
Ibeam - incident (photons/s/m2 )
re - classical electron radius (2.818x10-15 m)
hkl - index of pixel (a·(up+us)/λ)
a - orientation (recip. cell vectors)
up,us - unit vector pointing at pixel,source
λ - x-ray wavelength (in meters!)
N - number of cells (each direction)
Ω - solid angle of pixel (steradian)
P - polarization factor
(1+cos2(2θ) -Pfac∙cos(2Φ)sin2(2θ))/2
A - attenuation factor exp(-μxtal∙lpath)
F(hkl) - structure amplitude (electrons)
Circa 1820s
see: Kirian et al. (2010)
P A | F(hkl) |2sin(πN·hkl)
sin(π·hkl)Ipixel = Ibeam re
2 Ω2
Scattering: atom by atom
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 0.5 1 1.5 2
one
two
h index
inte
nsity
Scattering: atom by atom
0123456789
10
0 0.5 1 1.5 2
one
two
three
h index
inte
nsity
Scattering: atom by atom
0
2
4
6
8
10
12
14
16
18
0 0.5 1 1.5 2
two
three
four
h index
inte
nsity
Scattering: atom by atom
0
5
10
15
20
25
30
0 0.5 1 1.5 2
three
four
five
h index
inte
nsity
Scattering: atom by atom
0
5
10
15
20
25
30
35
40
0 0.5 1 1.5 2
four
five
six
h index
inte
nsity
Scattering: atom by atom
0
10
20
30
40
50
60
0 0.5 1 1.5 2
five
six
seven
h index
inte
nsity
Scattering: atom by atom
0
10
20
30
40
50
60
70
0 0.5 1 1.5 2
six
seven
eight
h index
inte
nsity
Scattering: atom by atom
0
10
20
30
40
50
60
70
80
90
0 0.5 1 1.5 2
seven
eight
nine
h index
inte
nsity
Inter-Bragg spots over-sample unit cell
square
round
Why SINBAD?
I+ I-
Different structures (non-isomorphism)
New source of error in SFX
Dear James
The story of the two forms of lysozyme crystals goes back to about 1964 when it was found that the diffraction patterns from different crystals could be placed in one of two classes depending on their intensities. This discovery was a big set back at the time and I can remember a lecture title being changed from the 'The structure of lysozyme' to 'The structure of lysozyme two steps forward and one step back'. Thereafter the crystals were screened based on intensities of the (11,11,l) rows to distinguish them (e.g. 11,11,4 > 11,11,5 in one form and vice versa in another). Data were collected only for those that fulfilled the Type II criteria. (These reflections were easy to measure on the linear diffractometer because crystals were mounted to rotate about the diagonal axis). As I recall both Type I and Type II could be found in the same crystallisation batch . Although sometimes the external morphology allowed recognition this was not infallible.
The structure was based on Type II crystals. Later a graduate student Helen Handoll examined Type I. The work, which was in the early days and before refinement programmes, seemed to suggest that the differences lay in the arrangement of water or chloride molecules (Lysozyme was crystallised from NaCl). But the work was never written up. Keith Wilson at one stage was following this up as lysozyme was being used to test data collection strategies but I do not know the outcome.
An account of this is given in International Table Volume F (Rossmann and Arnold edited 2001) p760.
Tony North was much involved in sorting this out and if you wanted more info he would be the person to contact. I hope this is helpful. Do let me know if you need more.
Best wishes
Louise
Non-isomorphism in lysozyme
0
100
200
300
400
500
600
700
800
900
0 1 2 3
F(11,11,4)
F(11,11,5)
Johnson’s ratio
Str
uct
ure
fac
tor
(e- )
Non-isomorphism in lysozyme
0
100
200
300
400
500
600
700
800
900
0 1 2 3
F(11,11,4)
F(11,11,5)
Johnson’s ratio
Str
uct
ure
fac
tor
(e- )
Non-isomorphism in lysozyme
RH 84.2% vs 71.9% Riso = 44.5%RMSD = 0.18 Å
Non-isomorphism in lysozyme
Dear James
The story of the two forms of lysozyme crystals goes back to about 1964 when it was found that the diffraction patterns from different crystals could be placed in one of two classes depending on their intensities. This discovery was a big set back at the time and I can remember a lecture title being changed from the 'The structure of lysozyme' to 'The structure of lysozyme two steps forward and one step back'. Thereafter the crystals were screened based on intensities of the (11,11,l) rows to distinguish them (e.g. 11,11,4 > 11,11,5 in one form and vice versa in another). Data were collected only for those that fulfilled the Type II criteria. (These reflections were easy to measure on the linear diffractometer because crystals were mounted to rotate about the diagonal axis). As I recall both Type I and Type II could be found in the same crystallisation batch . Although sometimes the external morphology allowed recognition this was not infallible.
The structure was based on Type II crystals. Later a graduate student Helen Handoll examined Type I. The work, which was in the early days and before refinement programmes, seemed to suggest that the differences lay in the arrangement of water or chloride molecules (Lysozyme was crystallised from NaCl). But the work was never written up. Keith Wilson at one stage was following this up as lysozyme was being used to test data collection strategies but I do not know the outcome.
An account of this is given in International Table Volume F (Rossmann and Arnold edited 2001) p760.
Tony North was much involved in sorting this out and if you wanted more info he would be the person to contact. I hope this is helpful. Do let me know if you need more.
Best wishes
Louise
Non-isomorphism in lysozyme
Non-isomorphism = dehydration?
= 1 nL
100 μm
Anomalous difference is resilient to non-isomorphism
Nucleus
Synthetic light collecting structure
0 20 40 60 80 100
Riso (%)
1.0
0.8
0.6
0.4
0.2
Co
rrel
atio
n C
oef
fici
ent
of
ΔF
ano 100 x 100
lysozyme PDBs
Why SINBAD?
New sources of error in SFX:
1.Partiality
2.Dynamic range
3.Jitter
4.Non-isomorphism
?
SINBAD diffractometer concept
Nucleus
Synthetic light collecting structureh,k,l
-h,-k,-l
Detec
tor Detector
Detec
tor Detector
d = 3.5 Å d = 3.5 Å
d = 3.5 Åd = 3.5 Å
sample injector
Mirr
ors
Mirr
ors
d = 3.5 Åλ = 5 Å
XFEL beam
h,k,l
-h,-k,-l
Detec
tor Detector
Detec
tor Detectorλ = 5 Å
sample
injector
Si(111)
52.87degSi(111)Si(111)
Si(111)
Si(111)
Si(111)
2 Multilayer mirrorsd=2nm, W/B4C
KB Horiz focusKB vertical focus
~ 1m
How to reflect x-rays at 90° ?
λ = 2 d sinθSilicon: absorbs ~50%/bounce
Diamond:Unit cell too small
Platinum:Too soft = high mosaic
Iridium: high hardnessCsI: just miss edge
d = 0.7 λ
Want:Large structure factorLow absorbance
Most promising:
Summaryhttp://bl831.als.lbl.gov/~jamesh/powerpoint/ACA_SINBAD_2013.ppt
• SFX introduces new sources of error
• Software solutions are tractable, but hard
• SINBAD could solve them “in hardware”
• Non-isomorphism can be controlled?
• Mono xtal has applications for seeding
Muybridge’s galloping horse (1878)
Muybridge’s multi-camera
Hot questions: 21st centuryhow do molecules work?
Beernink, Endrizzi, Alber & Schachman (1999). PNAS USA 96, 5388-5393.
a “crystal” of horses
realistic “crystal” of horses
average structure: galloping horse
not enough signal
brighter light
even brighter
very bright light
average structure: galloping horse
Horse: real and reciprocal
Supporting a model with data
Molecular Dynamics Simulation
1aho Scorpion toxin
0.96 Å resolution64 residuesSolvent: H20 + acetate
Cerutti et al. (2010).J. Phys. Chem. B 114, 12811-12824.
using realcrystal’s lattice
30 conformers from 24,000
Electron density from 24,000 conformers
Regular model with real data!
Molecular Dynamics vs Observation
Fobs
1aho.cif 1aho.pdb
Fsim FcalcFcalc
Rcryst= 0.137 Rcryst= 0.116Rvault = 0.69
refined_vs_Fsim.pdb
LSQ rmsd = 0.43Å
rmsd = 1.05 Å
1aho 64-residue scorpion toxin in water to 1.0 Å resolution
Rvault = 0.48 to 4 Å
Riso =
Molecular Dynamics vs Observation
RMSD1.05 Å
Molecular Dynamics vs Observation
RMSD0.45 Åaligned