3UB6

Periplasmic portion of the Helicobacter pylori chemoreceptor TlpB with urea bound

Summary for 3UB6

• Entry DOI: 10.2210/pdb3ub6/pdb
• Related: 3UB7 3UB8 3UB9
• Descriptor: chemoreceptor TlpB, UREA, SULFATE ION, ... (6 entities in total)
• Functional Keywords: homodimer, four-helix bundle, pas domain, membrane protein
• Biological source: Helicobacter pylori
• Total number of polymer chains: 2
• Total formula weight: 42718.30

Authors

Henderson, J.N.,Sweeney, E.G.,Goers, J.,Wreden, C.,Hicks, K.G.,Parthasarathy, R.,Guillemin, K.J.,Remington, S.J. (deposition date: 2011-10-23, release date: 2012-06-27, Last modification date: 2024-02-28)

Primary citation

Goers Sweeney, E.,Henderson, J.N.,Goers, J.,Wreden, C.,Hicks, K.G.,Foster, J.K.,Parthasarathy, R.,Remington, S.J.,Guillemin, K.
Structure and proposed mechanism for the pH-sensing Helicobacter pylori chemoreceptor TlpB.
Structure, 20:1177-1188, 2012

PubMed Abstract: pH sensing is crucial for survival of most organisms, yet the molecular basis of such sensing is poorly understood. Here, we present an atomic resolution structure of the periplasmic portion of the acid-sensing chemoreceptor, TlpB, from the gastric pathogen Helicobacter pylori. The structure reveals a universal signaling fold, a PAS domain, with a molecule of urea bound with high affinity. Through biophysical, biochemical, and in vivo mutagenesis studies, we show that urea and the urea-binding site residues play critical roles in the ability of H. pylori to sense acid. Our signaling model predicts that protonation events at Asp114, affected by changes in pH, dictate the stability of TlpB through urea binding.

PubMed: 22705207
DOI: 10.1016/j.str.2012.04.021

Experimental method

X-RAY DIFFRACTION (1.38 Å)