PXLP-K56-SRR dimer isomerises L-Ser to D-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 the catabolism of L-Serine by alpha,beta-elimination of water to form pyruvate (Foltyn et al. 2005). A small part of L-Serine does not undergo deamination so SRR can also mediate the minor reversible isomerisation of L-Ser to D-Ser (De Miranda et al. 2000, Xia et al. 2004). 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
11054547 Human serine racemase: moleular cloning, genomic organization and functional analysis

De Miranda, J, Santoro, A, Engelender, S, Wolosker, H

Gene 2000
15193426 Characterization and localization of a human serine racemase

Xia, M, Liu, Y, Figueroa, DJ, Chiu, CS, Wei, N, Lawlor, AM, Lu, P, Sur, C, Koblan, KS, Connolly, TM

Brain Res. Mol. Brain Res. 2004
Participant Of
Catalyst Activity
Catalyst Activity
serine racemase activity of PXLP-K56-SRR dimer [cytosol]
Physical Entity
This event is regulated
Orthologous Events