Structural basis of a phosphotransferase system xylose transporter

Takahashi, Y. S.; Kohga, H.; Chek, M. F.; Yamamoto, K.; Takahashi, J. F.; Shigematsu, H.; Tanaka, Y.; Ichikawa, M.; Miyazaki, R.; Hakoshima, T.; Tsukazaki, T.

doi:10.1101/2025.04.02.646771

bioRxiv · 10.1101/2025.04.02.646771

Structural basis of a phosphotransferase system xylose transporter

Takahashi, Y. S.·Kohga, H.·Chek, M. F.·Yamamoto, K.·Takahashi, J. F.·Shigematsu, H.·Tanaka, Y.·Ichikawa, M.·Miyazaki, R.·Hakoshima, T.·Tsukazaki, T.

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Abstract

The bacterial phosphotransferase system (PTS) is essential for carbohydrate uptake, and IIC transporters in the system facilitate intracellular sugar transport. Here, we report the crystal and cryo-EM structures of Leminorella grimontii GatC (LgGatC), a putative xylose transporter in the IIC family, in its outward-facing state. Structural analysis indicates that the outward-facing cavity recognizes the linear form of D-xylose. A structure-based homology model of an inward-facing state supports an elevator-like sugar transport mechanism. These findings provide insights into PTS-mediated xylose transport and its potential applications in microbial engineering.

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Takahashi, Y. S., Kohga, H., Chek, M. F., Yamamoto, K., Takahashi, J. F., Shigematsu, H., Tanaka, Y., Ichikawa, M., Miyazaki, R., Hakoshima, T., Tsukazaki, T.. 2025-04-03. Structural basis of a phosphotransferase system xylose transporter. https://doi.org/10.1101/2025.04.02.646771

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