Ph.D.: Weizmann Institute of Science, Israel
Post-doctorate: University of British Columbia, Canada
Position: Senior Lecturer
Department of Life Sciences
Faculty of Natural Sciences
E-mail: zarivach@bgu.ac.il 

Webpage: http://lifeserv.bgu.ac.il/wb/zarivach/

 

Crystallographic studies of biological macromolecules

  • Background

Structural biology aims to understand the chemistry, interactions and basic biological functions governed by the three-dimensional structure of macromolecules. Knowledge of the 3-D structure of a protein can provide enormous basic scientific insight into the function of that protein, facilitating elucidation of its biochemical function and its interactions with other proteins, RNA, DNA, or membranes in the cell. Similarly, protein-ligand interactions are crucial in many biological processes with implications for drug targeting and gene expression. X-ray crystallography is the most prolific technique for the structural analysis of proteins and protein complexes, and remains the 'gold standard' in terms of accuracy. Using X-ray crystallography, we can now realize to the high-resolution range, up to atomic or even electronic details, enabling a full coverage understanding of macromolecules and their interactions. Crystallography is the key methodology for macromolecule-ligand interaction research, as part of structure-based drug design, shedding light on the molecular details of such interactions or for use in ligand-screening of large ligand libraries.

  • Current research
  1. Magnetotactic bacteria are a phylogenetically and morphologically diverse group of microorganisms that share an ability to create magnetosomes, biomineral organelles that senses geomagnetic fields and aid the bacteria to align themselves accordingly. The magnetosome organelle comprises aligned 30-50 nm iron oxide magnetite crystals, surrounded by a lipid bilayer membrane vesicle. There are several types of magnetosome-forming proteins all encoded by genes within a genomic island common to magnetotactic bacteria. These proteins include a set of incorporated membrane proteins that facilitate vesicle formation, vesicle localization and iron transport and a set of proteins that control magnetite formation and size. A large number of the proteins involved in magnetosome formation are of unknown function.         Magnetite crystals formed by magnetotactic bacteria have a high potential for nano- and biotechnological applications, which require specifically-designed particle surfaces of distinct shape and size. Using a biomimetic approach, we can use the purified proteins, possibly mutated, to design and control the magnetite crystals, for many uses including protein tags and fluorophores. For commercial use, magnetite crystals with a permanent stable magnetic dipole moment at room temperature and with a specific size can be designed. 

  2. As a member of the Faculty of Natural Sciences at BGU, the lab will serve as a core facility and will be involved in protein structure determination and structural studies of other proteins. Together with the lab of Dr. Amir Aharoni, addressing directed evolution, the lab of Prof. Varda Shoshan-Barmatz, studying membrane proteins and ion channels, the lab of Prof. Angel Porgador, considering innate immunity responses, the lab of Prof. Amir Sagi, working biomineralization.

  • Selected publications

Zeytuni N., Ozyamak E., Ben-Harush K., Davidov G., Levin M., Gat Y., Moyal T., Brik A., Komeili A. and Zarivach R. (2011). Self-recognition mechanism of MamA, a magnetosome-associated TPR-containing protein, promotes complex assembly. Proc. Natl. Acad. Sci. USA. 108(33):E480-E487.

Zeytuni N., Baran D., Davidov G. and Zarivach R. (2012). Inter-phylum structural conservation of the magnetosome-associated TPR-containing protein, MamA. J. Struct. Biol. 180(3):479-487.

Zeytuni N. and Zarivach R. (2012). Structural and functional discussion of the tetra-trico-peptide repeat, a protein interaction module. Structure 20(3):397-405.

Guttman C., Davidov G., Shaked H., Kolusheva S., Bitton R., Ganguly A., Miller J.F., Chill J.H. and Zarivach R. (2013). Characterization of the N-terminal domain of BteA: A Bordetella Type III secreted cytotoxic effector. PLoS ONE 8(1):e55650.

Guttman C., Davidov G., Yahalom A., Shaked H., Kolusheva S., Bitton R., Barber-Zucker S., Chill J.H. and Zarivach R. (2013). BtcA, a Class IA Type III Chaperone, Interacts with the BteA N-Terminal Domain through a Globular/Non-Globular Mechanism. PLoS ONE 8(12):e81557.