Understanding Water Equilibration Fundamentals as a Step for Rational Protein Crystallization

• Type: Article in International Scientific Journal
• Date: 2008

Authors

Pedro M Martins (Author) FEUP; Fernando Rocha (Author) FEUP; Ana M Damas (Author) ICBAS

Journal

Title: PLoS ONE

Vol. 3 No. 4

Final page: e1998

ISSN: 1932-6203

Publisher: Public Library of Science

Indexing

ISI Web of Knowledge - 9 Citations

ISI Web of Science

Scopus - 11 Citations

Scientific classification

CORDIS: Technological sciences > Engineering > Chemical engineering

Other information

Authenticus ID: P-004-042

DOI: 10.1371/journal.pone.0001998

Abstract (EN): Background: Vapor diffusion is the most widely used technique for protein crystallization and the rate of water evaporation plays a key role on the quality of the crystals. Attempts have been made in the past to solve the mass transfer problem governing the evaporation process, either analytically or by employing numerical methods. Despite these efforts, the methods used for protein crystallization remain based on trial and error techniques rather than on fundamental principles. Methodology/Principal Findings: Here we present a new theoretical model which describes the hanging drop method as a function of the different variables that are known to influence the evaporation process. The model is extensively tested against experimental data published by other authors and considering different crystallizing conditions. Aspects responsible for the discrepancies between the existing theories and the measured evaporation kinetics are especially discussed; they include the characterization of vapor-liquid equilibrium, the role of mass transfer within the evaporating droplet, and the influence of the droplet-reservoir distance. Conclusions/Significance: The validation tests show that the proposed model can be used to predict the water evaporation rates under a wide range of experimental conditions used in the hanging drop vapor-diffusion method, with no parameter fitting or computational requirements. This model combined with protein solubility data is expected to become a useful tool for a priori screening of crystallization conditions.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10