Characterization of aldolase from Methanococcus jannaschii by gas chromatography.
The products of reactions catalyzed by Methanococcus. jannaschii (Mj) aldolase using various substrates were identified by gas chromatography (GC). Although Mj aldolase is considered a fuculose-1-phosphate aldolase based on homology searching after gene sequencing, it has not been proven to be a fuculose-1-phosphate aldolase based on its reaction products. Mj aldolase was found to catalyze reactions between glycoaldehyde or D, L-glyceraldehyde and DHAP (dihydroxyacetone phosphate). Before performing GC the ketoses produced were converted into peracetylated alditol derivatives by sequential reactions, i.e., dephosphorylation, NaBH(4) reduction, and acetylation. By comparing the GC data of final products with those of standard alditol samples, it was found that the enzymatic reactions with glycoaldehyde, D-glyceraldehyde, and D, L-glyceraldehyde produced D-ribulose-1-phosphate, D-psicose-1-phosphate, and a mixture of D-psicose and L-tagatose-1-phosphate, respectively. These results provide direct evidence that Mj aldolase is a fuculose-1-phosphate aldolase.
Nam Shin
Jeong E
JE
Department of Chemistry, Soongsil University, Dongakgu Sangdo 5 dong, Seoul 156-743, Korea.
Kim
Mi-Jung
MJ
Choi
Ji-ah
JA
Chun
Keun Ho
KH
D002849:Chromatography, Gas / Q000379:methods*; D005634:Fructose-Bisphosphate Aldolase / Q000737:chemistry* / Q000378:metabolism*; D006600:Hexosephosphates / Q000737:chemistry / Q000378:metabolism; D017017:Methanococcus / Q000201:enzymology*; D015394:Molecular Structure; D010429:Pentoses / Q000737:chemistry / Q000378:metabolism; D013379:Substrate Specificity
D006600:Hexosephosphates; D010429:Pentoses; C048089:fuculose 1-phosphate; C100182:ribulose; D005634:Fructose-Bisphosphate Aldolase