In general, I would say the main problem with micro-g protein
crystallization is that its benefits obviously depend on the
inhibition of convection. The problem with this is that the very same
effect can be achived by crystallization in a gel matrix - With a
ridiculously low fraction of the costs.
Clemens
Zitat von Jack Reynolds <[log in to unmask]>:
> TITLE: "Extracting trends from two decades of microgravity
> macromolecular crystallization history" (2005) (Judge, Snell and van
> der Woerd).
>
> "Significant enhancements in structural knowledge have resulted from
> X-ray diffraction of the crystals grown . . . in the reduced
> acceleration environnments of an orbiting spacecraft."
>
>
> TITLE: "Macromolecular Crystallization in Microgravity Generated by
> a Superconducting Magnet" (2006) (Wakayama, Yin, Harata, Kiyoshi,
> Fujiwara and Tanimoto).
>
> "About 30% of the protein crystals grown in space yield better X-ray
> diffraction data than the best crystals grown on the earth."
>
>
> TITLE: "The crystallization of biological macromolecules under
> microgravity: a way to more accurate three-dimensional structures?"
> (2002) (Lorber).
>
> "The crystallization of proteins . . . in a microgravity environment
> can produce crystals having lesser defects than crystals prepared
> under normal gravity on earth. Such microgravity-grown crystals can
> diffract X-rays to a higher resolution and have a lower mosaic
> spread."
>
>
> TITLE: "Protein crystal growth on board Shenzhou 3: a concerted
> effort improves crystal diffraction quality and facilitates
> structure determination." (2004) (Han, Cang, Zhou, Wang, Bi,
> Colelesage, Delbaere, Nahoum, Shi, Zhou, Zhue and Lin)
>
> ". . . careful and concerted planning at all stages made it possible
> to obtain crystals of improved quality compared to their ground
> controls for some of the proteins. Significantly improved
> resolutions were obtained from diffracted crystals of 4 proteins. A
> complete data set from a space crystal of the PEP carboxykinase
> yielded significantly higher resolution, and a lower average
> temperature factor than the best ground-based control crystal."
>
>
> TITLE: "JAXA-GCF project - High-quality protein crystals grown under
> microgravity environment for better understand of protein
> structure." (2006). (Sato, Tanaka, Inaka, Shinozaki, Yamanaka,
> Takahashi, Yamanaka, Hirota, Sugiyama, Kato, Saito, Sano, Motohara,
> Nakamura, Kobayashi, and Yoshitomi.)
>
> "JAXA has developed technologies for growing, in microgravity,
> high-quality protein crystals, which may diffract up to atomic
> resolution, for a better understanding of 3-dimensional rpotein
> structures through X-ray diffraction experiments."
>
>
> TITLE: "A Comparison between Simulations and Experiments for
> Microgravity Crystal Growth in Gradient Magnetic Fields." (2008).
> (Poodt, et al.).
>
> "Microgravity protein crystal growth is expected to lead to an
> improvement of protein crystal quality, compared to crystals grown
> under normal gravity, due to the suppression of buoyancy driven
> convection. This is highly relevant, because for protein structure
> determination by X-ray diffraction, protein crystallization is often
> the quality limiting step."
>
>
> TITLE: "Macromolecular crystallization in microgravity." (2005)
> (Snell and Helliwell).
>
> "Density difference fluid flows and sedimentation of growing
> crystals are greatly reduced when crystallization takes place in a
> reduced gravity environment."
>
>
> TITLE: "Comparison of space- and ground-grown Bi2Se.21Te2.79
> thermoelectric crystals." (2010). (Zhou, et al.)
>
> "The compositions of the space crystal grown along growth direction
> were more homogeneous than that of the ground crystal grown. The
> crystallization of space crystal grown was obviously improved."
>
>
> That's just a handful of quotes from a few of the sources I have
> accumulated over the last few months. I guess this all boils down to
> your definition of "significantly improved crystals."
>
> Is there something wrong with these sources? Am I misunderstanding
> their findings?
>
> Jack
>
>
> --- On Sun, 5/9/10, Dunten, Pete W. <[log in to unmask]> wrote:
>
>
>> "significantly improved crystals " I
>> wasn't aware that was an accepted generalization, born out
>> by the experiments already conducted.
>> Can you cite a number of cases?
>>
>> Another issue for pharma would be the timeline.
>> Chemistry programs move pretty fast, and if the xray
>> crystallographers don't keep up,
>> they aren't very useful.
>>
>> Pete
>> ________________________________________
>> From: CCP4 bulletin board [[log in to unmask]]
>> On Behalf Of Jack Reynolds [[log in to unmask]]
>> Sent: Sunday, May 09, 2010 11:26 AM
>> To: [log in to unmask]
>> Subject: [ccp4bb] Clarification and another question . . .
>>
>> --- On Sun, 5/9/10, Klaus Fütterer <[log in to unmask]>
>> wrote:
>>
>> > Dear Jack,
>> >
>> > I believe your venture would enter a mature market,
>> and, if
>> > you were to offer growing growing crystals in
>> microgravity,
>> > a market characterised by very high costs and
>> (presumably)
>> > very low margins.
>>
>> I wouldn't offer crystal growth, I would offer access to
>> the data from x-ray diffraction of space-grown crystals. Is
>> the data from significantly improved crystals not a valuable
>> commodity?
>>
>> If the pharmaceutical industry (and other researchers, for
>> that matter) could grow crystals in space, and extract
>> critical data from the x-ray diffraction of these
>> space-grown crystals (in space); AND
>>
>> if costs could be reduced by 30-50%; AND
>>
>> if the end-product is the data, not the crystals . . .
>>
>> do you still think (profit) margins would be nominal?
>>
>> Is your assessment of "very low margins" based on assumed
>> "very high costs?"
>>
>> Jack
>>
>
>
--------------------------------------------------
Dr. Clemens Grimm
Institut für Biochemie
Biozentrum der Universität Würzburg
Am Hubland
D-97074 Würzburg
Germany
e-mail: [log in to unmask]
phone : +49 0931 888 84031
-------------------------------------------------
|