3W40

Crystal structure of RsbX in complex with magnesium in space group P1

Summary for 3W40

• Entry DOI: 10.2210/pdb3w40/pdb
• Related: 3W41 3W42 3W43 3W44 3W45
• Descriptor: Phosphoserine phosphatase RsbX, MAGNESIUM ION (3 entities in total)
• Functional Keywords: signaling protein, stressosome, environmental stress, phosphoric monoester hydrolases, dephosphorylation, tertiary, phosphatase, hydrolase, protein phosphatase, magnesium/manganese binding, alpha-beta beta-alpha sandwich fold
• Biological source: Bacillus subtilis
• Total number of polymer chains: 2
• Total formula weight: 44392.67

Authors

Teh, A.H.,Makino, M.,Baba, S.,Shimizu, N.,Yamamoto, M.,Kumasaka, T. (deposition date: 2013-01-04, release date: 2014-01-22, Last modification date: 2023-11-08)

Primary citation

Teh, A.H.,Makino, M.,Hoshino, T.,Baba, S.,Shimizu, N.,Yamamoto, M.,Kumasaka, T.
Structure of the RsbX phosphatase involved in the general stress response of Bacillus subtilis
Acta Crystallogr.,Sect.D, 71:1392-1399, 2015

PubMed Abstract: In the general stress response of Bacillus subtilis, which is governed by the sigma factor σ(B), stress signalling is relayed by a cascade of Rsb proteins that regulate σ(B) activity. RsbX, a PPM II phosphatase, halts the response by dephosphorylating the stressosome composed of RsbR and RsbS. The crystal structure of RsbX reveals a reorganization of the catalytic centre, with the second Mn(2+) ion uniquely coordinated by Gly47 O from the β4-α1 loop instead of a water molecule as in PPM I phosphatases. An extra helical turn of α1 tilts the loop towards the metal-binding site, and the β2-β3 loop swings outwards to accommodate this tilting. The residues critical for this defining feature of the PPM II phosphatases are highly conserved. Formation of the catalytic centre is metal-specific, as crystallization with Mg(2+) ions resulted in a shift of the β4-α1 loop that led to loss of the second ion. RsbX also lacks the flap subdomain characteristic of PPM I phosphatases. On the basis of a stressosome model, the activity of RsbX towards RsbR-P and RsbS-P may be influenced by the different accessibilities of their phosphorylation sites.

PubMed: 26057679
DOI: 10.1107/S1399004715007166

Experimental method

X-RAY DIFFRACTION (1.3 Å)