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bioRxiv · 10.1101/2023.05.05.539553

Structure-function analysis of the cyclic beta-1,2-glucan synthase

Sedzicki, J.·Ni, D.·Lehmann, F.·Stahlberg, H.·Dehio, C.
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Abstract

The synthesis of complex sugars is a key aspect of microbial biology. Cyclic {beta}-1,2-glucan (C{beta}G) is a circular polysaccharide critical for host interactions of many bacteria, including major pathogens of humans (Brucella) and plants (Agrobacterium). C{beta}G is produced by the cyclic glucan synthase (Cgs), a massive multi-domain membrane protein. So far, its structure as well as the mechanisms underlining the synthesis have not been clarified. Here we use cryo-electron microscopy (cryo-EM) and functional approaches to study Cgs from A. tumefaciens. We were able to determine the structure of this complex protein machinery and clarify key aspects of C{beta}G synthesis. Our research opens new possibilities for combating pathogens that rely on polysaccharide virulence factors and can lead to new synthetic biology approaches for producing complex cyclic sugars.

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Sedzicki, J., Ni, D., Lehmann, F., Stahlberg, H., Dehio, C.. 2023-05-05. Structure-function analysis of the cyclic beta-1,2-glucan synthase. https://doi.org/10.1101/2023.05.05.539553

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