Meeting report

BioCrys2006

Oeiras, Portugal, October 6-13, 2006

[Tutorial session]A typical tutorial session in the computer room during BioCrys2006
The third BioCrys-Course on ‘Fundamentals of Modern Methods in Biocrystallography’, organized by Maria Arménia Carrondo (ITQB Oeiras, Portugal) and Thomas Schneider (FIRC Inst. of Molecular Oncology, Milan, Italy) took place in the Inst. de Tecnologia Química e Biológica in Oeiras, Portugal, October 6-13, 2006. The course was supported by EMBO, MAX-INF2 cooperation network, BIOXHIT Integrated project, the IUCr, FEBS, The British Council, FLAD, the Cambridge Crystallographic Data Centre, Oeiras Council, Qiagen and Corning. It brought together 36 students and 19 tutors from 20 and 10 different countries, respectively.

Subtitled ‘What you always wanted to know about crystallography but never dared to ask ...’, the course aimed at teaching the fundamental concepts of macromolecular crystallography to scientists in the early stage of their crystallographic career. In fact, while learning the efficient use of automated tools in crystallography, it is also critical to understand the underlying concepts for tackling difficult problems of structural biology that are not amenable to the current generation of these tools.

Lectures and tutorials covered topics all the way from the cooling of crystals to the validation of the final structural model. For the computational tutorials, a cluster of 18 Linux-computers was used, especially set up for the course by Pedro Matias and Daniele de Sanctis (both from ITQB). The scientific program of most days was concluded with an evening lecture, in which tutors or invited speakers reported about a current topic in structural biology.

Ed Hough (U. Tromsø, Norway) laid out the basics of crystallography in real and reciprocal space. Sean McSweeney (ESRF, France) gave an overview about the principles of X-ray sources and beamline automation and Elspeth Garman (Oxford U., UK) lectured and demonstrated about the practical side of crystal cooling and data collection. Kevin Cowtan (U. York, UK) guided the students through the world of structure factors and how they relate to electron densities in his web-based tutorial (www.yorvic.york.ac.uk/~cowtan/sfapplet/sfintro.html). The understanding of the basics was complemented by a tour of crystallographic resources on the world wide web by Isabel Bento (ITQB) and Daniele de Sanctis.

Strategic questions of data collection and both theoretical and practical aspects of data processing were addressed by Zbyszek Dauter (Argonne Nat’l. Lab., USA) and Andrew Leslie (MRC, UK). This included practicals on integration and scaling of diffraction data.

Gordon Leonard (ESRF, France) gave an introduction to the use of anomalous scattering in macromolecular crystallography. The substructure solution process and MAD-phasing where covered by Thomas Schneider (IFOM, Italy). Kevin Cowtan discussed the principles of the different density modification techniques used for phase improvement and Zbyszek Dauter explained various aspects of SAD-phasing. Molecular Replacement was introduced and discussed with the help of examples by Pedro Matias. Carlos Frazão (ITQB) described solutions to problems that one encounters with twinned crystals.

Other topics covered includes the MIR-method (Clemens Vonrhein, GlobalPhasing, UK), maximum likelihood (Kevin Cowtan), symmetry (Zbyszek Dauter), and refinement and model precision (Thomas Schneider).

The central topics of the remaining two days were molecular replacement and both manual and automated model building. Automated model building and refinement was discussed from methodological and practical points of view by Anastassis Perrakis (NKI, The Netherlands). Morten Kjeldgaard (U. of Aarhus, Denmark) taught the principles and practicalities of manual model building. The discussion of model building was complemented by an overview about the tools and concepts for assessing the correctness of a model by different validation criteria by Margarida Archer (ITQB).

The subjects of evening lectures were protein synthesis by Anders Liljas (Lund U., Sweden), RNA degradation by Maria Arménia Carrondo (ITQB Oeiras), and the preparation of protein samples for crystallization by Peter Donner (Schering AG, Germany).

‘Burning questions’ submitted anonymously were answered by the tutors in a dedicated session.

[Group photo]Photo group of the participants at BioCrys2006
The City Council of Oeiras generously invited all participants to dinner at the restaurant Caravela Douro where they enjoyed local cuisine and had a hands on introduction to regional folk dances. We thank our sponsors for generous support. We are also grateful to the informatics staff of ITQB and Mafalda Mateus for handling administration and logistics of the course very efficiently.

Maria Arménia Carrondo and Thomas R. Schneider, Organizers