Re: [ccp4bb]: smallest diffracting crystals?

[Anastassis Perrakis <perrakis@nki.nl>]

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> I am interested to know:
>
>  What size is the smallest dimension protein crystal for
> which you have obtained usable diffraction data
> on any synchrotron beamline.
>
> I will be happy to summarize in the form of a histogram
> if I get enough response.
>

from the microfocus (ID13) experience between 1998-2000:

±3.2 A from ±5 micron thick plates (? not 100% sure of size ) from Rod 
Mackinon's pumps ... - fairly anisotropic -
a few datasets collected, some of which are used in Rod's nature 
paper(s).. not sure which one(s) .. he gets too many ;-))

±3.5 A from ±1 micron thick plates  for Werner Kuehlbrant's photosystem 
- VERY anisotropic, I don't know what
happened to these data

3.2 A from one ±30x5x2 micron xtal from O. Weichenrieder's/S.Cusack's 
Alu RNP isotropic (c221, complete data collected, 60Kd in AU)

A funny cubic thingy from Stefania diMarco. M. Walsh et al, was 
30x30x30 xtals and diffracted at 3.0 but it was 'nightmare in space 
group street'

Belgian group for an iron containing protein got data on needles of 
5-10 micron thickness 9veeeery long ones) up to 1.4 A !!!

The Dortmund group had several pretty small xtals of GTPases that gave 
usuable data ... I am sure (?) Renaud and Klaus can
enlighten us on the details of these

30x10x10 crystals (hey, these were mine !) were measured at 2.0, never 
reproduced and I wish I knew what was inside
(45 kD protein- 22mer DNA complex but not both would fit - or the 
structure would be really weird .. structure pending)

OF COURSE
I am carefully avoiding all the things of similar size or bigger that 
never diffracted beyond 15-20 A !!!
but the question was 'what WORKED ?'  ;-))

.... maybe I forget a few other small xtals but these are the ones that 
surfaced up in my memory now ...

	A.