A New Concept for Crystallization of Membrane Proteins

Structure determination of membrane proteins (MPs) is currently regarded as one of the major challenges in structural biology, precluding efficient drug development due to the lack of relevant biochemical information at the atomic level. Unlike their water-soluble counterparts, in order to produce large, well-ordered crystals, MPs are generally extracted from their membranous environment with detergents and further manipulated as protein/detergent complexes (PDCs), where the target MP is enclosed in a detergent micelle.

I shall present a potentially general crystallization approach that differs conceptually from these crystallization methods as it relies on specific micellar conjugation mechanisms capable of bringing PDCs into proximity and stabilizing their nucleation centers. Consistent with the above, two micellar conjugation mechanisms, one that relies on peptide amphiphiles and the other on amphiphilic chelators, were studied. Both mechanisms were shown to concentrate target MPs without denaturing them. The use of an appropriate [amphiphilic chelator:metal] complex led to the growth of large (> 0.1mm), purple-colored, hexagon-shaped crystals of the light driven H+-pump bacteriorhodopsin (bR). Extension of this strategy to other MPs will also be discussed.

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Abstract Reference & Short Personal Biography of Presenting Author

Thien Van Truong, Ariel University

Ph.D.: 2018-current in Chemistry and Biotechnology
Department of Chemical Sciences, Ariel University, Israel

MSc.: 2012-2014 in Biotechnology
Department of Biotechnology, Da Nang University of Science and Technology, Viet Nam

B.Sc.: 2004-2009 in Biotechnology
Department of Biotechnology, Da Nang University of Science and Technology, Viet Nam

Publications:

1. Truong et al., Crystallization of retinal proteins with amphiphiplic [metal:chelator] complexes
(in preparation)

2. Truong et al., Conjugation of native membranes with oligo-amines (in preparation)

3. Truong et al., Micelle Conjugation via Charged Peptide Amphiphiles Peptide Sci. (2019)
accepted communication.

4. Le Phuoc Cuong, Truong Van Thien, Le Thi Xuan Thuy, Gumerov Farid. Determination of organic and inorganic compounds in the human body, who is living nearby Hoa Khanh Industrial Park, central of Viet Nam. Int. J Adv. Res. Chem. Sci. (2015) 2, 41- 51.
5. Ta Ngoc Ly, Quach Thi Toan, Truong Van Thien. IAA producing of chicken feather biodegradation bacteria and application of feather lysate as plant growth promoting agent, J. Sci Technol. (2015) 92, pp 90-93.
6. Pham Thi Huong, Tran Thi Ha Ny, Nguyen Quang Dat, Truong Van Thien, Nguyen Thi Lan Anh, Research on soy yogurt production from kefir. J. Sci. Technol. (2015) 96, pp 105-109.