BACKGROUND: The rpoS, nlpD, pcm, and surE genes are among many whose expression is induced during the stationary phase of bacterial growth. rpoS codes for the stationary-phase RNA polymerase sigma subunit, and nlpD codes for a lipoprotein. The pcm gene product repairs damaged proteins by converting the atypical isoaspartyl residues back to L-aspartyls. The physiological and biochemical functions of surE are unknown, but its importance in stress is supported by the duplication of the surE gene in E. coli subjected to high-temperature growth. The pcm and surE genes are highly conserved in bacteria, archaea, and plants. RESULTS: The structure of SurE from Thermotoga maritima was determined at 2.0 A. The SurE monomer is composed of two domains; a conserved N-terminal domain, a Rossman fold, and a C-terminal oligomerization domain, a new fold. Monomers form a dimer that assembles into a tetramer. Biochemical analysis suggests that SurE is an acid phosphatase, with an optimum pH of 5.5-6.2. The active site was identified in the N-terminal domain through analysis of conserved residues. Structure-based site-directed point mutations abolished phosphatase activity. T. maritima SurE intra- and intersubunit salt bridges were identified that may explain the SurE thermostability. CONCLUSIONS: The structure of SurE provided information about the protein's fold, oligomeric state, and active site. The protein possessed magnesium-dependent acid phosphatase activity, but the physiologically relevant substrate(s) remains to be identified. The importance of three of the assigned active site residues in catalysis was confirmed by site-directed mutagenesis.
BACKGROUND: The rpoS, nlpD, pcm, and surE genes are among many whose expression is induced during the stationary phase of bacterial growth. rpoS codes for the stationary-phase RNA polymerase sigma subunit, and nlpD codes for a lipoprotein. The pcm gene product repairs damaged proteins by converting the atypical isoaspartyl residues back to L-aspartyls. The physiological and biochemical functions of surE are unknown, but its importance in stress is supported by the duplication of the surE gene in E. coli subjected to high-temperature growth. The pcm and surE genes are highly conserved in bacteria, archaea, and plants. RESULTS: The structure of SurE from Thermotoga maritima was determined at 2.0 A. The SurE monomer is composed of two domains; a conserved N-terminal domain, a Rossman fold, and a C-terminal oligomerization domain, a new fold. Monomers form a dimer that assembles into a tetramer. Biochemical analysis suggests that SurE is an acid phosphatase, with an optimum pH of 5.5-6.2. The active site was identified in the N-terminal domain through analysis of conserved residues. Structure-based site-directed point mutations abolished phosphatase activity. T. maritima SurE intra- and intersubunit salt bridges were identified that may explain the SurE thermostability. CONCLUSIONS: The structure of SurE provided information about the protein's fold, oligomeric state, and active site. The protein possessed magnesium-dependent acid phosphatase activity, but the physiologically relevant substrate(s) remains to be identified. The importance of three of the assigned active site residues in catalysis was confirmed by site-directed mutagenesis.
Authors: E V Filippova; L Shuvalova; G Minasov; O Kiryukhina; Y Zhang; S Clancy; I Radhakrishnan; A Joachimiak; W F Anderson Journal: Proteins Date: 2011-06-01
Authors: Alexei Savchenko; Tatiana Skarina; Elena Evdokimova; James D Watson; Roman Laskowski; Cheryl H Arrowsmith; Aled M Edwards; Andrzej Joachimiak; Rong-guang Zhang Journal: Proteins Date: 2004-01-01
Authors: Aleksandra A Knapik; Janusz J Petkowski; Zbyszek Otwinowski; Marcin T Cymborowski; David R Cooper; Karolina A Majorek; Maksymilian Chruszcz; Wanda M Krajewska; Wladek Minor Journal: Proteins Date: 2012-06-30
Authors: Greg Brown; Alexander Singer; Vladimir V Lunin; Michael Proudfoot; Tatiana Skarina; Robert Flick; Samvel Kochinyan; Ruslan Sanishvili; Andrzej Joachimiak; Aled M Edwards; Alexei Savchenko; Alexander F Yakunin Journal: J Biol Chem Date: 2008-12-10 Impact factor: 5.157
Authors: Ruslan Sanishvili; Alexander F Yakunin; Roman A Laskowski; Tatiana Skarina; Elena Evdokimova; Amanda Doherty-Kirby; Gilles A Lajoie; Janet M Thornton; Cheryl H Arrowsmith; Alexei Savchenko; Andrzej Joachimiak; Aled M Edwards Journal: J Biol Chem Date: 2003-05-05 Impact factor: 5.157