Dear CCP4 members:
Sorry for the off-topic subject, but I'd appreciate it if you could
share your experience with methods that could easily detect or
distinguish carbohydrates, proteins, lipids and nucleic acids. The
story began with a 2D gel of a sample from IP. Instead of seeing
different foc
R factors cannot be used to detect twining. The traditional R
is calculated using structure factors (roughly the square root of
intensity) but you can't do that calculation in the presence of
twining because each structure factor contributes to two intensities.
The formula for the "R" in the pr
Thank you Dale,
I will "hit-the-books" to better the rotation matrices. I am concluding
from all of this that the space group is indeed P212121. So I still wonder
why I have some outliers in the intensity stats for the two additional
screw axis and why R and Rfree both drop by 5% when I apply a tw
Since Phil is no doubt in bed, I'll answer the easier part. Your
second matrix is nearly the equivalent position (x,-y,-z). This
is a two-fold rotation about the x axis. You also have a translation
of about 31 A along x so if your A cell edge is about 62 A you have
a 2_1 screw.
Dale Tronrud
Hi Phil,
Thanks for your help.
I ran a "Find-NCS" routine in the phenix package. It came up with what I
pasted below:
I am assuming the the first rotation matrix is just the identity. I need
to read more to understand rotation matrices but I think the second one
should have only a single -1 to ac
Thanks for all the great suggestions. They included beamline problems,
detector-specific problems, translational NCS, narrow dynamic range problem
for strong low resolution reflections,radiation damage, and more. The
agreement seems to be that no matter what the reason for the high Rsym is,
it is p
Hello Yarrow,
Since you have a refined molecular replacement solution I recommend
using that rather than global intensity statistics.
Obviously if you solve in P21 and it's really P212121 you should have
twice the number of molecules in the asymmetric unit and one half of the
P21 asymmetric
Hello crystallography experts,
I think I may have a case of perfect pseudomerehedral twinning where P222
Laue
symmetry is actually P2 with twinning and aniostropic data masks intensity
based
twinning statistics. I would like some input to determine if my reasoning
makes sense.
I would like to perf
Hello crystallography experts,
I think I may have a case of perfect pseudomerehedral twinning where P222
Laue
symmetry is actually P2 with twinning and aniostropic data masks intensity
based
twinning statistics. I would like some input to determine if my reasoning
makes sense.
I would like to perf
Hello crystallography experts,
I think I may have a case of perfect pseudomerehedral twinning where P222
Laue
symmetry is actually P2 with twinning and aniostropic data masks intensity
based
twinning statistics. I would like some input to determine if my reasoning
makes sense.
I would like to perf
CCP4 Study weekend 2014 on Complementary Techniques - programme now live at:
http://www.cse.scitech.ac.uk/events/CCP4_2014/programme.html
What techniques can be combined with crystallographic analysis? Of all
deposited structures in the PDB, more than half are oligomeric, and three
quarters hav
Immediate opening for a postdoc in structure-based drug discovery on any of
these projects:
1) inhibitor discovery against the Helicobacter pylori acid-gated urea channel
(ulcers, stomach cancer)
2) reactivation of p53 cancer mutants
3) inhibitors inosine monophosphate dehydrogenase (anti-P. f
Dear all,
I recently started using CCP4i (Windows 8) software for data processing and
model building but I get the following error messages whenever I use molrep and
refmac5:
MOLREP
#CCP4I TERMINATION STATUS 0 " MOLREP(ccp4): Error in label assignments in
LABIN"
#CCP4I TERMINATION TIME 08 Oct
Hi Ursula,
if you look at the Wilson plot, you see a minimum near 6A resolution. This
means that in the range 7-5A, intensities are low, and Rsyms are therefore
elevated.
best,
Kay
On Mon, 14 Oct 2013 11:52:03 -0700, Ursula Schulze-Gahmen
wrote:
>Here is some more info on the data:
>
>lowe
Izit is an aqueous solution of methylene blue, which you can prepare simply and
cheaply. Look here:
http://www.ysbl.york.ac.uk/ccp4bb/2000/msg00387.html
One word of warning: not every crystal stains. I found poking crystal with hair
or glass fibre to see if it cracks or breaks is more reliable
Dear All,
I am looking for a method to quickly differentiate between salt and protein
crystals. I have been told thats its a popular alternative to the
commercially available izit dye. I would appreciate if some one would share
their comassie crystal staining protocol.
Swastik
16 matches
Mail list logo
