8J9T

Crystal Structure of GyraseA N-terminal at 2.43A Resolution

Summary for 8J9T

• Entry DOI: 10.2210/pdb8j9t/pdb
• Descriptor: DNA gyrase subunit A, CARBONATE ION (3 entities in total)
• Functional Keywords: gyrase, gantd, salmonella, isomerase
• Biological source: Salmonella enterica subsp. enterica serovar Typhi str. CT18
• Total number of polymer chains: 2
• Total formula weight: 110866.62

Authors

Salman, M.,Sachdeva, E.,Das, U.,Singh, T.P.,Ethayathullah, A.S.,Kaur, P. (deposition date: 2023-05-04, release date: 2024-05-08, Last modification date: 2025-11-26)

Primary citation

Salman, M.,Sachdeva, E.,Negi, S.,Das, U.,Ethayathulla, A.S.,Kaur, P.
Structural and Comparative Stability of a Truncated N-Terminal Domain of DNA Gyrase A From Salmonella Typhi.
Proteins, 2025

PubMed Abstract: DNA Gyrase, a Type II topoisomerase, introduces negative supercoiling in dsDNA through the cleavage and religation activity at the expense of ATP. DNA Gyrase forms a hetero-tetrameric complex with two Gyrase A and Gyrase B subunits. These two subunits interact dynamically to physically transfer one DNA duplex through another by coupling ATP binding and hydrolysis with DNA binding, cleavage, and strand transport. The N-terminal domain of Gyrase A (GyrA-NTD) mediates the cleavage of the DNA strand and forms the target site for quinolones class of antibiotics. While structures of GyrA-NTD from several prokaryotes have been determined, the N-terminal segment (residues 1-32) remains unresolved in apo forms. Here, we present the crystal structure of a truncated GyrA-NTD (ΔGyrA-NTD; residues 33-530) from Salmonella Typhi at 2.43 Å resolution, alongside comparative biophysical characterization with the wild type. Thermal and chemical denaturation assays revealed that the wild-type GyrA-NTD is more prone to unfolding than the truncated variant, indicating that deletion of the unresolved N-terminal segment enhances domain stability. These findings uncover a structural element influencing GyrA-NTD stability.

PubMed: 41116293
DOI: 10.1002/prot.70070

Experimental method

X-RAY DIFFRACTION (2.428 Å)