PXLP-K56-SRR dimer deaminates L-Ser

Stable Identifier
Reaction [transition]
Homo sapiens
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N-methyl D-aspartate (NMDA) receptors play a key role in excitatory neurotransmission, learning, memory and synaptic plasticity. Their activity is modulated by the agonist glutamate and by the co-agonists D-Serine (D-Ser) and glycine (gly). In human brain, dimeric serine racemase (SRR), a pyridoxal 5'-phosphate-dependent enzyme (Smith et al. 2010), is a bifunctional enzyme mediating mainly L-Serine catabolism by alpha,beta-elimination of water to form pyruvate (De Miranda et al. 2002, Foltyn et al. 2005). Part of L-Serine is not deaminated then SRR can also catalyse the isomerisation of L-Ser to D-Ser although this is very much a minor reaction. Thus, D-Ser homeostasis in neurons is modulated by SRR, and therefore indirectly, modulates NMDA receptors. Targeting SRR could find potential in neurodegenerative diseases (Canu et al. 2014). Mg2+ and ATP stimulate SRR (De Miranda et al. 2002).

Literature References
PubMed ID Title Journal Year
12393813 Cofactors of serine racemase that physiologically stimulate the synthesis of the N-methyl-D-aspartate (NMDA) receptor coagonist D-serine

De Miranda, J, Panizzutti, R, Foltyn, VN, Wolosker, H

Proc. Natl. Acad. Sci. U.S.A. 2002
15536068 Serine racemase modulates intracellular D-serine levels through an alpha,beta-elimination activity

Foltyn, VN, Bendikov, I, De Miranda, J, Panizzutti, R, Dumin, E, Shleper, M, Li, P, Toney, MD, Kartvelishvily, E, Wolosker, H

J. Biol. Chem. 2005
Participant Of
Catalyst Activity
Catalyst Activity
D-serine ammonia-lyase activity of PXLP-K56-SRR dimer [cytosol]
Physical Entity
Orthologous Events
Cross References
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