8H5V

Crystal structure of the FleQ domain of Vibrio cholerae FlrA

Summary for 8H5V

• Entry DOI: 10.2210/pdb8h5v/pdb
• Descriptor: flagellar regulatory protein A, 1,2-ETHANEDIOL, SULFATE ION, ... (4 entities in total)
• Functional Keywords: sigma54 dependent transcription regulator, transcription
• Biological source: Vibrio cholerae O395
• Total number of polymer chains: 4
• Total formula weight: 57139.29

Authors

Dasgupta, J.,Chakraborty, S. (deposition date: 2022-10-14, release date: 2022-11-02, Last modification date: 2024-05-15)

Primary citation

Chakraborty, S.,Agarwal, S.,Bakshi, A.,Dey, S.,Biswas, M.,Ghosh, B.,Dasgupta, J.
The N-terminal FleQ domain of the Vibrio cholerae flagellar master regulator FlrA plays pivotal structural roles in stabilizing its active state.
Febs Lett., 597:2161-2177, 2023

PubMed Abstract: In Vibrio cholerae, the master regulator FlrA controls transcription of downstream flagellar genes in a σ -dependent manner. However, the molecular basis of regulation by VcFlrA, which contains a phosphorylation-deficient N-terminal FleQ domain, has remained elusive. Our studies on VcFlrA, four of its constructs, and a mutant showed that the AAA domain of VcFlrA, with or without the linker 'L', remains in ATPase-deficient monomeric states. By contrast, the FleQ domain plays a pivotal role in promoting higher-order functional oligomers, providing the required conformation to 'L' for ATP/cyclic di-GMP (c-di-GMP) binding. The crystal structure of VcFlrA-FleQ at 2.0 Å suggests that distinct structural features of VcFlrA-FleQ presumably assist in inter-domain packing. VcFlrA at a high concentration forms ATPase-efficient oligomers when the intracellular c-di-GMP level is low. Conversely, excess c-di-GMP locks VcFlrA in a non-functional lower oligomeric state, causing repression of flagellar biosynthesis.

PubMed: 37402215
DOI: 10.1002/1873-3468.14693

Experimental method

X-RAY DIFFRACTION (2 Å)