1NAT

CRYSTAL STRUCTURE OF SPOOF FROM BACILLUS SUBTILIS

Summary for 1NAT

• Entry DOI: 10.2210/pdb1nat/pdb
• Descriptor: SPORULATION RESPONSE REGULATORY PROTEIN (2 entities in total)
• Functional Keywords: aspartate pocket, sporulation response regulator, two component system, regulatory protein
• Biological source: Bacillus subtilis
• Cellular location: Cytoplasm (Probable): P06628
• Total number of polymer chains: 1
• Total formula weight: 14244.66

Authors

Madhusudan,Zapf, J.,Hoch, J.A.,Whiteley, J.M.,Xuong, N.H.,Varughese, K.I. (deposition date: 1997-09-09, release date: 1998-10-14, Last modification date: 2024-04-03)

Primary citation

Madhusudan, M.,Zapf, J.,Hoch, J.A.,Whiteley, J.M.,Xuong, N.H.,Varughese, K.I.
A response regulatory protein with the site of phosphorylation blocked by an arginine interaction: crystal structure of Spo0F from Bacillus subtilis.
Biochemistry, 36:12739-12745, 1997

PubMed Abstract: Spo0F is a secondary messenger in the "two-component" system controlling the sporulation of Bacillus subtilis. Spo0F, like the chemotaxis protein CheY, is a single-domain protein homologous to the N-terminal activator domain of the response regulators. We recently reported the crystal structure of a phosphatase-resistant mutant Y13S of Spo0F with Ca2+ bound in the active site. The crystal structure of wild-type Spo0F in the absence of a metal ion is presented here. A comparison of the two structures reveals that the cation induces significant changes in the active site. In the present wild-type structure, the carboxylate of Asp11 points away from the center of the active site, whereas when coordinated to the Ca2+, as in the earlier structure, it points toward the active site. In addition, Asp54, the site of phosphorylation, is blocked by a salt bridge interaction of an Arg side chain from a neighboring molecule. From fluorescence quenching studies with Spo0F Y13W, we found that only the amino acid Arg binds to Spo0F in a saturable manner (Kd = 15 mM). This observation suggests that a small molecule with a shape complementary to the active site and having a guanidinium group might inhibit phosphotransfer between response regulators and their cognate histidine kinases.

PubMed: 9335530
DOI: 10.1021/bi971276v

Experimental method

X-RAY DIFFRACTION (2.45 Å)