Immunogen sequence: NTCPGDRSAI TPGGLRLGAP ALTSRQFRED DFRRVVDFID EGVNIGLEVK SKTAKLQDFK SFLLKDSETS QRLANLRQRV EQFARAF Highest antigen sequence identity to the following orthologs: Mouse - 95%, Rat - 95%. Mammalian serine hydroxymethyltransferase (SHMT) is