Disease relevance of ECs3818

• This strain produces 80-fold more AdoMet synthetase than a wild type E. coli [1].

High impact information on ECs3818

• Methionine adenosyltransferase (MAT) catalyzes the synthesis of s-adenosylmethionine (AdoMet), a metabolite that plays an important role in a variety of cellular functions, such as methylation, sulfuration, and polyamine synthesis [2].
• The crystal structure of Escherichia coli AdoMet synthetase shows that the active site, which lies between two subunits, contains four lysines and one histidine as basic residues [3].
• Mutagenesis of glutamate 42 to glutamine (E42QMetK) abolished monovalent cation activation and produced an enzyme that has kinetic properties virtually identical to those of K(+)-free wild type AdoMet synthetase in both the overall AdoMet synthetase reaction and in the hydrolysis of tripolyphosphate [4].
• N-Ethylmaleimide-modified S-adenosylmethionine synthetase exists mainly as a dimer in conditions where the native enzyme is a tetramer [5].
• For this purification, a strain of E. coli which was derepressed for AdoMet synthetase and which harbors a plasmid containing the structural gene for AdoMet synthetase was constructed [1].

Chemical compound and disease context of ECs3818

• S-Adenosylmethionine synthetase from Escherichia coli is rapidly inactivated by N-ethylmaleimide [5].
• The crystal structure of Escherichia coli AdoMet synthetase shows that the active site contains four aspartate residues [6].
• The NMR-determined conformations of AdoMet and AMPPNP were docked into the E. coli AdoMet synthetase active site taken from the enzyme.ADP [7].
• Crystallographic studies of Escherichia coli AdoMet synthetase showed that arginine-244 is the only arginine near the polyphosphate-binding site [8].
• An Escherichia coli metK mutant, designated metK110, was isolated among spontaneous ethionine-resistant organisms selected at 42 degrees C. The S-adenosylmethionine synthetase activity of this mutant was present at lower levels than in the corresponding wild-type strain and was more labile than the wild-type enzyme when heated or dialyzed [9].

Anatomical context of ECs3818

• Refolding and characterization of rat liver methionine adenosyltransferase from Escherichia coli inclusion bodies [10].

Associations of ECs3818 with chemical compounds

• AMPPNP, an analogue of ATP, is resistant to the ATP hydrolysis activity of AdoMet synthetase because of the presence of a nonhydrolyzable NH-link between the beta- and gamma-phosphates but is a substrate for AdoMet formation during which tripolyphosphate is produced [7].
• The formation of AdoMet from ATP and L-methionine is catalyzed by S-adenosylmethionine synthetase (AdoMet synthetase) [7].
• Chemical modification of AdoMet synthetase by the arginine-specific reagents phenylglyoxal or p-hydroxyphenylglyoxal inactivates the enzyme [8].
• Minicells bearing the pBR322 hybrid plasmids and labeled with radioactive lysine synthesize radiolabeled proteins with Mrs corresponding to those reported for purified ODCase, ADCase and MATase [11].
• Growth at 46 degrees C, growth in the presence of alanine or glycyl-L-leucine, or growth of a strain with a mutational deficiency in S-adenosylmethionine synthetase (metK) greatly increased the synthesis of two other spots (spots II and IV) [12].

References