Purification and characterization of CMP-NeuAc:GM1 (Gal beta 1-4GalNAc) alpha 2-3 sialyltransferase from rat brain.
A CMP-NeuAc:GM1 alpha 2-3 sialyltransferase (GD1a synthase, 2.4.99.2) has been purified from the Triton extract of rat brain. The enzyme was purified and resolved by affinity chromatography on CDP-Sepharose column by a linear NaCl gradient elution. Final purification was achieved by elution from a 'GM1-acid'-Sepharose column. SDS-PAGE of the enzyme revealed a single protein band with an apparent Mr 44 kDa. It catalyzed specifically the sialylation of GD1b, GM1 and asialo-GM1. Enzyme products were identified by TLC in three different solvent systems. The Km value for GM1 was 7.5 x 10(-2) M, and for CMP-NeuAc it was 6.5 x 10(-5) M.
Gu
T J
TJ
Department of Biochemistry and Molecular Biophysics, Virginia Commonwealth University, Medical College of Virginia, Richmond 23298-0614.
Gu
X B
XB
Ariga
T
T
Yu
R K
RK
D000818:Animals; D001921:Brain / Q000201:enzymology*; D002846:Chromatography, Affinity; D005732:Gangliosides / Q000096:biosynthesis; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000302:isolation & purification; D051381:Rats; D012799:Sialyltransferases / Q000302:isolation & purification*
D005732:Gangliosides; D009419:Nerve Tissue Proteins; C021298:ganglioside, GD1a; D012799:Sialyltransferases; C019916:CMP-N-acetylneuraminic acid-monosialoganglioside sialyltransferase