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Human microsomal prostaglandin E synthase-1: purification, functional characterization, and projection structure determination.

Thoren, S; Weinander, R; Saha, S; Jegerschold, C; Pettersson, P L; Samuelsson, B; Hebert, Hans LU ; Hamberg, M; Morgenstern, R and Jakobsson, P J (2003) In Journal of Biological Chemistry 278(25). p.209-22199
Abstract
Human, microsomal, and glutathione-dependent prostaglandin (PG) E synthase-1 (mPGES-1) was expressed with a histidine tag in Escherichia coli. mPGES-1 was purified to apparent homogeneity from Triton X-100-solubilized bacterial extracts by a combination of hydroxyapatite and immobilized metal affinity chromatography. The purified enzyme displayed rapid glutathione-dependent conversion of PGH2 to PGE2 (Vmax; 170 µmol min–1 mg–1) and high kcat/Km (310 mM–1 s–1). Purified mPGES-1 also catalyzed glutathione-dependent conversion of PGG2 to 15-hydroperoxy-PGE2 (Vmax; 250 µmol min–1 mg–1). The formation of 15-hydroperoxy-PGE2 represents an alternative pathway for the synthesis of PGE2, which requires further investigation. Purified mPGES-1 also... (More)
Human, microsomal, and glutathione-dependent prostaglandin (PG) E synthase-1 (mPGES-1) was expressed with a histidine tag in Escherichia coli. mPGES-1 was purified to apparent homogeneity from Triton X-100-solubilized bacterial extracts by a combination of hydroxyapatite and immobilized metal affinity chromatography. The purified enzyme displayed rapid glutathione-dependent conversion of PGH2 to PGE2 (Vmax; 170 µmol min–1 mg–1) and high kcat/Km (310 mM–1 s–1). Purified mPGES-1 also catalyzed glutathione-dependent conversion of PGG2 to 15-hydroperoxy-PGE2 (Vmax; 250 µmol min–1 mg–1). The formation of 15-hydroperoxy-PGE2 represents an alternative pathway for the synthesis of PGE2, which requires further investigation. Purified mPGES-1 also catalyzed glutathione-dependent peroxidase activity toward cumene hydroperoxide (0.17 µmol min–1 mg–1), 5-hydroperoxyeicosatetraenoic acid (0.043 µmol min–1 mg–1), and 15-hydroperoxy-PGE2 (0.04 µmol min–1 mg–1). In addition, purified mPGES-1 catalyzed slow but significant conjugation of 1-chloro-2,4-dinitrobenzene to glutathione (0.8 µmol min–1 mg–1). These activities likely represent the evolutionary relationship to microsomal glutathione transferases. Two-dimensional crystals of purified mPGES-1 were prepared, and the projection map determined by electron crystallography demonstrated that microsomal PGES-1 constitutes a trimer in the crystal, i.e. an organization similar to the microsomal glutathione transferase 1. Hydrodynamic studies of the mPGES-1-Triton X-100 complex demonstrated a sedimentation coefficient of 4.1 S, a partial specific volume of 0.891 cm3/g, and a Stokes radius of 5.09 nm corresponding to a calculated molecular weight of 215,000. This molecular weight, including bound Triton X-100 (2.8 g/g protein), is fully consistent with a trimeric organization of mPGES-1. (Less)
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organization
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type
Contribution to journal
publication status
published
subject
in
Journal of Biological Chemistry
volume
278
issue
25
pages
209 - 22199
publisher
ASBMB
external identifiers
  • scopus:0038266571
ISSN
1083-351X
DOI
language
English
LU publication?
yes
id
4cd67a42-28d4-4b23-83e4-fdac3aff422e (old id 128535)
date added to LUP
2007-07-09 16:36:52
date last changed
2018-06-10 03:46:57
@article{4cd67a42-28d4-4b23-83e4-fdac3aff422e,
  abstract     = {Human, microsomal, and glutathione-dependent prostaglandin (PG) E synthase-1 (mPGES-1) was expressed with a histidine tag in Escherichia coli. mPGES-1 was purified to apparent homogeneity from Triton X-100-solubilized bacterial extracts by a combination of hydroxyapatite and immobilized metal affinity chromatography. The purified enzyme displayed rapid glutathione-dependent conversion of PGH2 to PGE2 (Vmax; 170 µmol min–1 mg–1) and high kcat/Km (310 mM–1 s–1). Purified mPGES-1 also catalyzed glutathione-dependent conversion of PGG2 to 15-hydroperoxy-PGE2 (Vmax; 250 µmol min–1 mg–1). The formation of 15-hydroperoxy-PGE2 represents an alternative pathway for the synthesis of PGE2, which requires further investigation. Purified mPGES-1 also catalyzed glutathione-dependent peroxidase activity toward cumene hydroperoxide (0.17 µmol min–1 mg–1), 5-hydroperoxyeicosatetraenoic acid (0.043 µmol min–1 mg–1), and 15-hydroperoxy-PGE2 (0.04 µmol min–1 mg–1). In addition, purified mPGES-1 catalyzed slow but significant conjugation of 1-chloro-2,4-dinitrobenzene to glutathione (0.8 µmol min–1 mg–1). These activities likely represent the evolutionary relationship to microsomal glutathione transferases. Two-dimensional crystals of purified mPGES-1 were prepared, and the projection map determined by electron crystallography demonstrated that microsomal PGES-1 constitutes a trimer in the crystal, i.e. an organization similar to the microsomal glutathione transferase 1. Hydrodynamic studies of the mPGES-1-Triton X-100 complex demonstrated a sedimentation coefficient of 4.1 S, a partial specific volume of 0.891 cm3/g, and a Stokes radius of 5.09 nm corresponding to a calculated molecular weight of 215,000. This molecular weight, including bound Triton X-100 (2.8 g/g protein), is fully consistent with a trimeric organization of mPGES-1.},
  author       = {Thoren, S and Weinander, R and Saha, S and Jegerschold, C and Pettersson, P L and Samuelsson, B and Hebert, Hans and Hamberg, M and Morgenstern, R and Jakobsson, P J},
  issn         = {1083-351X},
  language     = {eng},
  number       = {25},
  pages        = {209--22199},
  publisher    = {ASBMB},
  series       = {Journal of Biological Chemistry},
  title        = {Human microsomal prostaglandin E synthase-1: purification, functional characterization, and projection structure determination.},
  url          = {http://dx.doi.org/},
  volume       = {278},
  year         = {2003},
}