Precrystallization of human apoprotein A-I based on its aggregation behavior in solution studied by dynamic light scattering》.pdfVIP

Journal of MOLECULAR STRUCTURE ELSEVIER Journal of Molecular Structure 440 (1998) 1-8 Precrystallization of human apoprotein A-I based on its aggregation behavior in solution studied by dynamic light scattering Vfctor M. Bolafios-Garcfa ab, Jaime Mas-Oliva b, Manuel Soriano-Garcfa a, Abel Moreno a* Depto. de Bioestructura, lnstituto de Qulmica, Universidad Nacional Aut6noma de M~xico, Apdo. Postal 70-243, C.P. 04510, Ciudad Universitaria, Deleg., Coyoacdn, MFxico ~Depto. de Biquimica, lnstituto de Fisiologia Celular, Universidad Nacional Aut6noma de MFxico, Apdo. Postal 70-243, C.P. 04510, Ciudad Universitaria, Deleg., Coyoac6n, M~xico Received 11 December 1996;revised 31 March 1997;accepted 31 March 1997 Abstract This work reports several aspects concerning dynamic light scattering data of apoprotein A-I in solution. Using the geome- trical factor (H) and turbidity (r) at different pH values ranging from 5 to 10, we have tried to elucidate either if the initial formation of clusters and the trend for aggregation are carried out by nucleation or random mechanisms. Taking into account the solubility of the protein, this behavior depends on the precipitating agent used and the rate of mass transporting capacity carried out by vapor diffusion in small drops. Finally, we demonstrate that dynamic light scattering is