Serine racemase with catalytically active lysinoalanyl residue.
Serine racemase synthesizes d-serine, a physiological agonist of the NMDA receptor in mammalian brains. Schizosaccharomyces pombe produces serine racemase (spSR) that is highly similar to the brain enzyme. Our mass-spectrometric and X-ray studies revealed that spSR is modified with its natural substrate serine. spSR remains partially active even though its essential Lys57 inherently forming a Schiff base with the coenzyme pyridoxal 5'-phosphate is converted to N(6)-(R-2-amino-2-carboxyethyl)-l-lysyl (lysino-d-alanyl) residue. This indicates that the alpha-amino group of the d-alanyl moiety of the lysino-d-alanyl residue serves as a catalytic base in the same manner as the epsilon-amino group of Lys57 of the original spSR.
Yamauchi
Takae
T
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011, Japan.
Goto
Masaru
M
Wu
Hui-Yuan
HY
Uo
Takuma
T
Yoshimura
Tohru
T
Mihara
Hisaaki
H
Kurihara
Tatsuo
T
Miyahara
Ikuko
I
Hirotsu
Ken
K
Esaki
Nobuyoshi
N
D000411:Alanine Racemase / Q000378:metabolism; D055162:Biocatalysis; D020134:Catalytic Domain; D004789:Enzyme Activation; D008241:Lysinoalanine / Q000378:metabolism*; D019998:Racemases and Epimerases / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000201:enzymology*; D012694:Serine / Q000378:metabolism; D055672:Static Electricity; D000099300:Serine Racemase
D000411:Alanine Racemase; D008241:Lysinoalanine; D019998:Racemases and Epimerases; D012694:Serine; D000099300:Serine Racemase