Re: [ccp4bb] sudden drop in R/Rfree
Hi Rajesh, If you're seeing a lot of extra density coming up in the map in regions where you previously added waters, is it possible that this extra density corresponds to a part of your protein that you previously thought was disordered and is thus missing from the current model? At this resolution you wouldn't expect to see many waters. Also, to the best of my knowledge, the relative weighting of the X-ray and geometry terms in BUSTER is set by the program so as to produce a rmsd in bond lengths equal to a target value. The default value of this is 0.01 Ang (I think) but you can change this using the -r option on the command line. Using a lower value will reduce the weight on the X-ray term and may lower the R/R-free gap. Best wishes, Joe > > > Dear All, > I have a 3.3 A data for a protein whose SG is P6522. Model used was wild > type structure of same protein at 2.3 A. After molecular replacement, > first three rounds of refinement the R/Rf was 26/32.8, 27.1/31.72 % and > 7.35/30.88 % respectively.In the fourth round I refined with TLS and NCS > abd added water and the R/Rf dropped to 19.34/26.46. It has almost 7% > difference. I also see lot of unanswerable density in the map where lot of > waters were placed. Model fits to the map like a low resolution data with > most of side chains don't have best density. > I was not expecting such a sudden drop in the R/Rfree and a difference is > 7.2%. I am wondering if I am in right direction. I am not sure if this > usual for 3.3A data or in general any data if we consider the difference. > I appreciate your valuable suggestions. > ThanksRaj > >
Re: [ccp4bb] vector and scalars
> The definition game is on! :) > > Vectors are supposed to have direction and amplitude, unlike scalars. I think that this is part of the problem here. Whilst vector quantities do possess both size and direction, not everything that possesses size and direction is necessarily a vector by definition. Thus, just because complex numbers possess an amplitude and a phase angle, that does not automatically make them vectors. The complex numbers are in fact a vector space over the real numbers, but that requires further justification. > Curiously, one can take a position that real numbers are vectors too, if > you consider negative and positive numbers having opposite directions > (and thus subtraction is simply a case of addition of a negative > number). And of course, both scalars and vectors are simply tensors, of > zeroth and first order :) > > Guess my point is that definitions are a matter of choice in math and if > vector is defined as an array which must obey addition and scaling rules > (but there is no fixed multiplication rule - regular 3D vectors have > more than one possible product), then complex numbers are vectors. In a > narrow sense of a real space vectors (the arrow thingy) they are not. > Thus, complex number is a Vector, but not the vector (futile attempt at > using articles by someone organically suffering from article dyslexia). > > Cheers, > > Ed. > > > On Thu, 2010-10-14 at 14:24 +0200, Tim Gruene wrote: >> On Thu, Oct 14, 2010 at 12:34:30PM +0100, Ian Tickle wrote: >> > Formally, a complex number (e.g. a structure factor) is not a vector. >> Formally, C is isomorphous to R^2 (at least that's what math departments >> in >> Germany teach, and it's not difficult to prove), therefore complex >> numbers are >> vectors. That's is unaffected by whether there is a ring-isomorphism >> between C >> and R^2, and it's correct that the elements of a field are usually not >> called >> 'vectors', but that does not mean that it is wrong to consider a complex >> number >> a vector. >> >> Tim >> >> > Just because the addition & subtraction rules (i.e. 'a+b' & 'a-b') are >> > defined for real numbers, complex numbers and vectors doesn't make a >> > complex number a vector, any more than it makes a real number a vector >> > (or vice versa). Entities are defined according to the rules of >> > algebra that they obey, thus real and complex numbers obey the same >> > rules, i.e. the familiar addition, subtraction, multiplication, >> > division & raising to a power. Hence real and complex numbers are >> > both scalars: a real number is a special case of a complex scalar with >> > zero imaginary part (one could program an algorithm for reals using >> > only complex variables & functions and still get the right answer). >> > This also means that the transcendental functions (sin, cos, tan, exp, >> > log etc) are all defined equally well for both real and complex >> > scalars, but not for vectors, a property that programmers in Fortran, >> > C & C++ (and probably others) will be familiar with. Of the addition, >> > subtraction, multiplication, division & power rules, vectors only obey >> > the first two, but unlike real & complex scalars they also obey the >> > scalar product and exterior product rules. >> > >> > The general rule is that "if and only if it looks like a duck, waddles >> > like a duck and quacks like a duck, then it is a duck" - complex >> > numbers might look like vectors but they neither waddle nor quack like >> > them! >> > >> > Cheers >> > >> > -- Ian >> > >> > On Wed, Oct 13, 2010 at 9:57 PM, Yong Y Wang >> wrote: >> > > It is already vertical, relative to the real part of Fa (in red), >> i.e. the >> > > blue vector is always vertical to the red vector in this picture >> (and >> > > counter-clockwise). >> > > >> > > Yong >> > > >> > > >> > > >> > > >> > > William Scott >> > > Sent by: CCP4 bulletin board >> > > 10/13/2010 01:48 PM >> > > Please respond to >> > > William Scott >> > > >> > > >> > > To >> > > CCP4BB@JISCMAIL.AC.UK >> > > cc >> > > >> > > Subject >> > > [ccp4bb] embarrassingly simple MAD phasing question >> > > >> > > >> > > >> > > >> > > >> > > >> > > Hi Citizens: >> > > >> > > Try not to laugh. >> > > >> > > I have an embarrassingly simple MAD phasing question: >> > > >> > > Why is it that F" in this picture isn't required to be vertical >> (purely >> > > imaginary)? >> > > >> > > http://www.doe-mbi.ucla.edu/~sawaya/tutorials/Phasing/phase.gif >> > > >> > > (Similarly in the Harker diagram of the intersection of phase >> circles, one >> > > sees this.) >> > > >> > > I had a student ask me and I realized that there is this fundamental >> gap >> > > in my understanding. >> > > >> > > Many thanks in advance. >> > > >> > > -- Bill >> > > >> > > >> > > >> > > >> > > William G. Scott >> > > Professor >> > > Department of Chemistry and Biochemistry >> > > and The Center for the Molecular Biology of RNA >> > > 228 Sinsheimer Laboratories >> > > University of California
Re: [ccp4bb] vector and scalars
Electrical current is a 4-vector, is it not? > Correct! - and an alternating electric current is represented as a > complex number (then it's conventional to use the symbol 'j' for > sqrt(-1) to avoid confusion with 'i', the symbol for electric > current!). Since as you say electric current is a scalar not a > vector, then a complex number has to be a scalar, not a vector! > > Cheers > > -- Ian > > On Thu, Oct 14, 2010 at 3:47 PM, Ganesh Natrajan wrote: >> The definition of a vector as being something that has 'magnitude' and >> 'direction' is actually incorrect. If that were to be the case, a >> quantity like electric current would be a vector and not a scalar. >> Electric current is a scalar. >> >> A vector is something that transforms like the coordinate system, while >> a scalar does not. In other words, if you were to transform the >> coordinate system by a certain operator, a vector quantity in the old >> coordinate system can be transformed into the new one by using exactly >> the same operator. This is the correct definition of a vector. >> >> G. >> >> >> >> On Thu, 14 Oct 2010 10:22:59 -0400, Ed Pozharski >> wrote: >>> The definition game is on! :) >>> >>> Vectors are supposed to have direction and amplitude, unlike scalars. >>> Curiously, one can take a position that real numbers are vectors too, >>> if >>> you consider negative and positive numbers having opposite directions >>> (and thus subtraction is simply a case of addition of a negative >>> number). And of course, both scalars and vectors are simply tensors, >>> of >>> zeroth and first order :) >>> >>> Guess my point is that definitions are a matter of choice in math and >>> if >>> vector is defined as an array which must obey addition and scaling >>> rules >>> (but there is no fixed multiplication rule - regular 3D vectors have >>> more than one possible product), then complex numbers are vectors. In >>> a >>> narrow sense of a real space vectors (the arrow thingy) they are not. >>> Thus, complex number is a Vector, but not the vector (futile attempt at >>> using articles by someone organically suffering from article dyslexia). >>> >>> Cheers, >>> >>> Ed. >>> >>> >>> O >> -- >> ** >> Blow, blow, thou winter wind >> Thou art not so unkind >> As man's ingratitude; >> Thy tooth is not so keen, >> Because thou art not seen, >> Although thy breath be rude. >> >> -William Shakespeare >> ** >> >
Re: [ccp4bb] Bfactor is zero?
Hi, I saw the same thing once and the cause was that the crystal had been hideously over-exposed during data collection. As a result, essentially all the spots at lower than 2.5A resolution were overloaded. The Wilson plot was thus more or less flat at medium to high resolution and accordingly the Wilson B was very low (less than 1A**2). As in your case, the first indication of the problem was that the atomic B-factors were refining to ridiculously low values (although of course REFMAC was only doing the right thing). Hope that helps, Joe > Hi Bill, > > if you put a water oxygen in place where a heavier atom is, then water > oxygen's B-factor will refine to a value close to zero. This is the > feature > that we currently use as one of many criteria to develop automatic > identification and building of metals. > > Overall Wilson B-factor of 0.6A**2 tells that there is something weird > about > the data. What is the resolution? > > Pavel. > > PS> As Nat mentioned, PHENIX related questions are best to send to PHENIX > (and not CCP4) mailing list: > http://www.phenix-online.org/ > > > On Mon, Dec 20, 2010 at 7:34 AM, Zhibing Lu wrote: > >> Hi All, >> Recently I solved a structure in which some water molecules have >> Bfactors >> at 0 and overall wilson Bfactor is 0.654 based on PHENIX refinement. Is >> it >> possible? >> Bill Lu >> >
Re: [ccp4bb] Lattice sampling and resolution - a seeming paradox?
Dear Dirk, You are getting confused about where the sampling occurs, and this is perhaps because we usually learn about the Shannon criterion from a certain way around (sampling in real/time space -> periodicity of the signal transform in frequency/reciprocal space). To see the Shannon criterion in crystallography, you have to look at it the other way around (sampling of the molecular transform in reciprocal space -> periodicity of the electron density in space). "Twice the signal bandwidth" becomes the physical width of the unique portion of your 1D electron density, which is equal to the unit cell repeat by definition. Hence, you are sampling the fourier transform at double the Shannon frequency. Sampling of the electron density makes the sampled molecular transform periodic in reciprocal space, with interval 1/q, where q is your real-space sampling interval. If d is the minimum Bragg spacing, then your molecular transform lies between +/- 1/d in reciprocal space, i.e. has a full-width of 2/d. Thus, in order for the "ghost" copies of the molecular transform to not overlap, you must have q such that 1/q >= 2/d. i.e. q <= d/2. Hope that helps, Joe > Dear Ian, > > oh, yes, thank you - you are absolutely right! I really confused the > sampling of the molecular transform with the sampling of the electron > density in the unit cell! Sometimes I don't see the wood for the trees! > > Let me then shift my question from the sampling of the molecular > transform to the sampling of the electron density within the unit cell. > For the 1-dimensional case, this is discretely sampled at a/h for > resolution d, which is still 1x sampling and not 2x sampling, as > required according to Nyquist-Shannon. Where is my error in reasoning, > here? > > Best regards, > > Dirk. > > Am 15.04.11 14:25, schrieb Ian Tickle: >> Hi Dirk >> >> I think you're confusing the sampling of the molecular transform with >> the sampling of the electron density. You say "In the 1-dimensional >> crystal, we sample the continuous molecular transform at discrete >> reciprocal lattice points according to the von Laue condition, S*a = >> h". In fact the sampling of the molecular transform has nothing to do >> with h, it's sampled at points separated by a* = 1/a in the 1-D case. >> >> Cheers >> >> -- Ian >> >> On Fri, Apr 15, 2011 at 12:20 PM, Dirk Kostrewa >> wrote: >>> Dear colleagues, >>> >>> I just stumbled across a simple question and a seeming paradox for me >>> in >>> crystallography, that puzzles me. Maybe, it is also interesting for >>> you. >>> >>> The simple question is: is the discrete sampling of the continuous >>> molecular >>> Fourier transform imposed by the crystal lattice sufficient to get the >>> desired information at a given resolution? >>> >>> From my old lectures in Biophysics at the University, I know it has >>> been >>> theoretically proven, but I don't recall the argument, anymore. I >>> looked >>> into a couple of crystallography books and I couldn't find the answer >>> in any >>> of those. Maybe, you can help me out. >>> >>> Let's do a simple gedankenexperiment/thought experiment in the >>> 1-dimensional >>> crystal case with unit cell length a, and desired information at >>> resolution >>> d. >>> >>> According to Braggs law, the resolution for a first order reflection >>> (n=1) >>> is: >>> >>> 1/d = 2*sin(theta)/lambda >>> >>> with 2*sin(theta)/lambda being the length of the scattering vector |S|, >>> which gives: >>> >>> 1/d = |S| >>> >>> In the 1-dimensional crystal, we sample the continuous molecular >>> transform >>> at discrete reciprocal lattice points according to the von Laue >>> condition, >>> S*a = h, which gives |S| = h/a here. In other words, the unit cell with >>> length a is subdivided into h evenly spaced crystallographic planes >>> with >>> distance d = a/h. >>> >>> Now, the discrete sampling by the crystallographic planes a/h is only >>> 1x the >>> resolution d. According to the Nyquist-Shannon sampling theorem in >>> Fourier >>> transformation, in order to get a desired information at a given >>> frequency, >>> we would need a discrete sampling frequency of *twice* that frequency >>> (the >>> Nyquist frequency). >>> >>> In crystallography, this Nyquist frequency is also used, for instance, >>> in >>> the calculation of electron density maps on a discrete grid, where the >>> grid >>> spacing for an electron density map at resolution d should be<= d/2. >>> For >>> calculating that electron density map by Fourier transformation, all >>> coefficients from -h to +h would be used, which gives twice the number >>> of >>> Fourier coefficients, but the underlying sampling of the unit cell >>> along a >>> with maximum index |h| is still only a/h! >>> >>> This leads to my seeming paradox: according to Braggs law and the von >>> Laue >>> conditions, I get the information at resolution d already with a 1x >>> sampling >>> a/h, but according to the Nyquist-Shannon sampling theory, I would need >>> a 2x >>>
Re: [ccp4bb] Lattice sampling and resolution - a seeming paradox?
> Assume you have a one dimensional crystal with a 10 Angstrom repeat. > Someone has told you the value of the electron density at 10 equally > spaced points in this little unit cell, but you know nothing about the > value of the function between those points. I could spend all night > with a crayon drawing different functions that exactly hit all 10 points - > They are infinite in number and each one has a different set of Fourier > coefficients. How can I control this chaos and come up with a simple > description, particularly of the reciprocal space view of these 10 > points? > > The Nyquist-Shannon sampling theorem simply means that if we assume > that all Fourier coefficient of wave length shorter than 2 Angstrom/cycle > (twice our sampling rate) are defined equal to zero we get only one > function that will hit all ten points exactly. If we say that the 2 > A/cycle > reflection has to be zero as well, there are no functions that hit all ten > points (except for special cases) but if we allow the next reflection (the > h=6 or 1.67 A/cycle wave) to be non-zero we are back to an infinite number > of solutions. > Dear Dale, I'm not sure that this is true. Let's assume that the Fourier transform of the continuous function is band-limited, and the real-space sampling rate is over twice the Shannon frequency. There are at least *two* different mathematical functions that pass precisely through your sampled values: 1. the original continuous function, and 2. the sampled values themselves. One could perfectly reconstruct the original continuous function using a low pass "top-hat" filter of width +/-1/2q about the origin in reciprocal space (where q is the real-space sampling interval), thus cutting out the higher resolution "ghosts". In real space, this corresponds to convolution of your samples with a sinc function (sinc(x/(q/2)) up to a multiplicative constant). But you could also filter your samples using wider top hats to include higher resolution ghosts (between +/-(2n+1)/2q, where n is an integer), corresopnding to narrower sinc functions in the real-space interplation and therefore resulting in different continuous functions. All these functions will pass though the initial set of sampled values*, but will differ inbetween. For example, in the limit of making your reciprocal space top-hat filter very wide indeed, your sinc function in the real-space interpolation will be delta function-like and will give you a reconstructed continuous function that will look almost like your sequence of sampled values. So I think that even if your function is band-limited and is sampled at a rate greater than twice the Nyquist frequency, there are still an infinite number of functions that can be derived from the samples and that will pass through them. Am I wrong? Joe *The transforms of these continuous functions will have local translational symmetry in reciprocal space that is derived from the periodicity of the transform of the original unfiltered samples. If you now sample these functions at the same positions as with the original function, their transform will be identical to the transform of the original samples (because the periodicity imposed by the sampling will be in register with the translational symmetry mentioned above). So the values obtained from sampling functions derived from the different interpolation schemes must be identical to the original set of samples. > That's all it is - If you assume that all the Fourier coefficients of > higher resolution than twice your sampling rate are zero you are > guaranteed > one, and only one, set of Fourier coefficients that hit the points and the > Discrete Fourier Transform (probably via a FFT) will calculate that set > for > you. > > As usual, if your assumption is wrong you will not get the right > answer. > If you have a function that really has a non-zero 1.67 A/cycle Fourier > coefficient but you sample your function at 10 points and calculate a > FFT you will get a set of coefficients that hit the 10 points exactly > (when back transformed) but they will not be equal to "true" values. > > The overlapping spheres that Gerard Bricogne described are simply the > way of calculating the manor in which the coefficients are distorted by > this bad assumption. Ten Eyck, L. F. (1977). Acta Cryst. A33, 486-492 > has an excellent description. > > If you are certain that your function has no Fourier components higher > than your sampling rate can support then the FFT is your friend. If your > function has high resolution components and you don't sample it finely > enough then the FFT will give you an answer, but it won't be the correct > answer. The answer will exactly fit the points you sampled but it will > not correctly predict the function's behavior between the points. > > The principal situations where this is a problem are: > > Calculating structure factors (Fcalc) from a model electron density map. > Calculating gradients
Re: [ccp4bb] Improve diffraction ...any ideas?
Hi Urmi, When you say "antibody" you mean Fab fragments? If so, bear in mind that Fab fragments can be quite flexible about the region inbetween the variable and constant domains, which may be detrimental to the quality of your crystals ... in this case, further to the advice of others on here, you might consider engineering an ScFv construct for your antibody. The constant domains of the antibody are not usually involved in antigen binding, so the scFv should bind to the antigen in exactly the same way as the Fab, but being less flexible it might give you better crystals. Hope that helps, Joe > Hi, > > I am working on a protein antibody complex which readily crystallizes > (crystals form overnight and grow over 2-3 days) in 0.1M Bicine pH 9, 10 % > PEG8000. The crystals are chunky - shaped like a parallelogram but they > diffract poorly to about 8 à . > > I have tried the following to improve diffraction: > 1.Screen different temperatures 4°C - crystals have bad form and 10°C > crystals grow slower but diffraction does not improve. > 2.I have done an additive screen â A few hits came up like Yttrium > Chloride and Acetonitrile but they donât improve diffraction either > 3.I have tried streak seeding this does not help either > 4.Tested different cryo protectants â MPD, PEG400, Ethylene glycol and > glycerol - 10 - 15% glycerol seems to work best > 5.Not sure if cryo protectant affects diffraction in this case â I will > look at room temp diffraction soon to rule this out. > 6.Typical diffraction images attached > > Does anyone have suggestions on what I could try to improve diffraction of > my crystals? > > > > Urmi Dhagat > St Vincent's Institute > > >
Re: [ccp4bb] Why Do Phases Dominate?
> Perhaps this was really my question: > > Do phases *necessarily* dominate a reconstruction of an entity from phases > and amplitudes, or are we stuck in a Fourier-based world-view? (Lijun > pointed out that the Patterson function is an example of a reconstruction > which ignores phases, although obviously it has its problems for > reconstructing the electron density when one has too many atoms.) But > perhaps there are other phase-ignoring functions besides the Patterson > that > could be used, instead of the Fourier synthesis? > > Simply: are phases *inherently* more important than amplitudes, or is this > merely a Fourier-thinking bias? > > Also, > > Are diffraction phenomena inherently or essentially Fourier-related, just > as, e.g., projectile trajectories are inherently and essentially > parabola-related? Is the Fourier synthesis really the mathematical essence > of the phenomenon, or is it just a nice tool? In far-field diffraction from a periodic object, yes, diffraction is inherently Fourier-related. The scattered amplitudes correspond mathematically to the Fourier coefficients of the periodic electron density function. You can find this in a solid state physics textbook, like Kittel, for example. > > Jacob > > *** > Jacob Pearson Keller > Northwestern University > Medical Scientist Training Program > Dallos Laboratory > F. Searle 1-240 > 2240 Campus Drive > Evanston IL 60208 > lab: 847.491.2438 > cel: 773.608.9185 > email: j-kell...@northwestern.edu > *** > > - Original Message - > From: "Marius Schmidt" > To: > Sent: Friday, March 19, 2010 11:10 AM > Subject: Re: [ccp4bb] Why Do Phases Dominate? > > >> You want to have an intuitive picture without >> any mathematics and theorems, here it is: >> >> each black spot you measure on the detector is >> the square of an amplitude of a wavelet. The amplitude >> says simply how much the wavelet goes up and down >> in space. >> Now, you can imagine that when you have many >> wavelets that go up and down, in the average, they >> all cancel and you have a flat surface on a >> body of water in 2D, or, in 3-D, a constant >> density. However, if the wavelet have a certain >> relationship to each other, hence, the mountains >> and valleys of the waves are related, you are able >> to build even higher mountains and even deeper valleys. >> This, however, requires that the wavelets have >> a relationship. They must start from a certain >> point with a certain PHASE so that they are able >> to overlap at another certain point in space to form, >> say, a mountain. Mountains are atomic positions, >> valleys represent free space. >> So, if you know the phase, the condition that >> certain waves overlap in a certain way is sufficient >> to build mountains (and valleys). So, in theory, it >> would not even be necessary to collect the amplitudes >> IF YOU WOULD KNOW the phases. However, to determine the >> phases you need to measure amplitudes to derive the phases >> from them in the well known ways. Having the phase >> you could set the amplitudes all to 1.0 and you >> would still obtain a density of the molecule, that >> is extremely close to the true E-density. >> >> Although I cannot prove it, I have the feeling >> that phases fulfill the Nyquist-Shannon theorem, since they >> carry a sign (+/- 180 deg). Without additional assumptions >> you must do a MULTIPLE isomorphous replacement or >> a MAD experiment to determine a unique phase (to resolve >> the phase ambiguity, and the word multiple is stressed here). >> You need at least 2 heavy atom derivatives. >> This is equivalent to a sampling >> of space with double the frequency as required by >> Nyquist-Shannon's theorem. >> >> Modern approaches use exclusively amplitudes to determine >> phase. You either have to go to very high resolution >> or OVERSAMPLE. Oversampling is not possible with >> crystals, but oversampled data exist at very low >> resolution (in the nm-microm-range). But >> these data clearly show, that also amplitudes carry >> phase information once the Nyquist-Shannon theorem >> is fulfilled (hence when the amplitudes are oversampled). >> >> Best >> Marius >> >> >> >> >> >> >> >> Dr.habil. Marius Schmidt >> Asst. Professor >> University of Wisconsin-Milwaukee >> Department of Physics Room 454 >> 1900 E. Kenwood Blvd. >> Milwaukee, WI 53211 >> >> phone: +1-414-229-4338 >> email: m-schm...@uwm.edu >> http://users.physik.tu-muenchen.de/marius/ >
[ccp4bb] 3 year postdoctoral position at the University of Leeds
Dear CCP4BB, I’m looking for a postdoc to join my research group at the Astbury Centre, University of Leeds, UK. This is a 3-year BBSRC-funded position to study proteins involved in a spectrum of inherited disorders (ciliopathies), using a range of structural and biophysical techniques. For more information please visit: https://jobs.leeds.ac.uk/Vacancy.aspx?ref=FBSMB1263 Closing date: 25th August 2023. Kind regards, Joe -- Dr Joseph J B Cockburn DPhil Program Leader, Biochemistry and Medical Biochemistry Group Leader and Lecturer in X-ray Crystallography The Astbury Centre for Structural and Molecular Biology School of Molecular and Cellular Biology Faculty of Biological Sciences University of Leeds Leeds LS2 9JT UK +44 (0)113 3430758 Sometimes I need to send emails in the evenings or at weekends, but I don’t expect a reply outside of your normal working hours. To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
[ccp4bb] Structural biology postdoc position at Astbury Centre, University of Leeds
Dear CCP4BB, I’m looking for a postdoc to join my research group at the Astbury Centre, University of Leeds, UK. This is a 3-year BBSRC-funded position to study proteins involved in a spectrum of inherited disorders (ciliopathies), using a range of structural and biophysical techniques. For more information please visit: https://jobs.leeds.ac.uk/Vacancy.aspx?ref=FBSMB1263 Closing date: 2nd November 2023. Kind regards, Joe -- Dr Joseph J B Cockburn DPhil Program Leader, Biochemistry and Medical Biochemistry Group Leader and Lecturer in X-ray Crystallography The Astbury Centre for Structural and Molecular Biology School of Molecular and Cellular Biology Faculty of Biological Sciences University of Leeds Leeds LS2 9JT UK +44 (0)113 3430758 Sometimes I need to send emails in the evenings or at weekends, but I don’t expect a reply outside of your normal working hours. To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
[ccp4bb] Post doc position at the Astbury Centre, University of Leeds, UK
Dear all, We have a 3-year postdoc position to work on a highly interdisciplinary project to study the structure and dynamics of ciliary proteins, in collaboration with Dr George Heath, Prof. Colin Johnson and Prof. Michelle Peckham. Please don't hesitate to contact any of us for more details! To apply for this role please go to: https://jobs.leeds.ac.uk/Vacancy.aspx?ref=FBSMB1274 Deadline for applications: 05th March 2024. Kind regards, Joe -- Dr Joseph J B Cockburn DPhil Program Leader, Biochemistry and Medical Biochemistry Group Leader and Lecturer in X-ray Crystallography The Astbury Centre for Structural and Molecular Biology School of Molecular and Cellular Biology Faculty of Biological Sciences University of Leeds Leeds LS2 9JT UK +44 (0)113 3430758 Sometimes I need to send emails in the evenings or at weekends, but I don’t expect a reply outside of your normal working hours. To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
