1KNX

HPr kinase/phosphatase from Mycoplasma pneumoniae

Summary for 1KNX

• Entry DOI: 10.2210/pdb1knx/pdb
• Descriptor: Probable HPr(Ser) kinase/phosphatase (2 entities in total)
• Functional Keywords: hpr kinase, hpr kinase/phosphatase, hprk/p, kinase, phosphatase, p-loop, walker a box, catabolite repression, transferase-hydrolase complex, transferase/hydrolase
• Biological source: Mycoplasma pneumoniae
• Total number of polymer chains: 6
• Total formula weight: 211661.81

Authors

Allen, G.S. (deposition date: 2001-12-19, release date: 2002-12-31, Last modification date: 2024-02-14)

Primary citation

Allen, G.S.,Steinhauer, K.,Hillen, W.,Stulke, J.,Brennan, R.G.
Crystal Structure of HPr Kinase/Phosphatase from Mycoplasma pneumoniae
J.Mol.Biol., 326:1203-1217, 2003

PubMed Abstract: HPr kinase/phosphatase (HPrK/P) modifies serine 46 of histidine-containing protein (HPr), the phosphorylation state of which is the control point of carbon catabolite repression in low G+C Gram-positive bacteria. To understand the structural mechanism by which HPrK/P carries out its dual, competing activities we determined the structure of full length HPrK/P from Mycoplasma pneumoniae (PD8 ID, 1KNX) to 2.5A resolution. The enzyme forms a homo-hexamer with each subunit containing two domains connected by a short loop. The C-terminal domain contains the well-described P-loop (Walker A box) ATP binding motif and takes a fold similar to phosphoenolpyruvate carboxykinase (PEPCK) from Escherichia coli as recently described in other HPrK/P structures. As expected, the C-terminal domain is very similar to the C-terminal fragment of Lactobacillus casei HPrK/P and the C-terminal domain of Staphylococcus xylosus HPrK/P; the N-terminal domain is very similar to the N-terminal domain of S.xylosus HPrK/P. Unexpectedly, the N-terminal domain resembles UDP-N-acetylmuramoyl-L-alanyl-D-glutamate:meso-diaminopimelate ligase (MurE), yet the function of this domain is unclear. We discuss these observations as well as the structural significance of mutations in the P-loop and HPrK/P family sequence motif.

PubMed: 12589763
DOI: 10.1016/S0022-2836(02)01378-5

Experimental method

X-RAY DIFFRACTION (2.5 Å)