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7776974 
Journal Article 
Purification, general properties and two other catalytic activities of -ketoglutarate:glyoxylate carboligase of Mycobacterium Phlei 
Yamasaki, H; Moriyama, T 
1971 
1 
Biochimica et Biophysica Acta
ISSN: 0006-3002
EISSN: 1878-2434 
242 
3 
637-647 
English 
5003720 
1. 1. An α-ketoglutarate; glyoxylate carboligase was purified 200- to 250-fold from the sonic extracts of Mycobacterium phlei by (NH4)2 SO4 fractionation, pH precipitation, starch block electrophoresis and column chromatography. 2. 2. From studies on decarboxylation from 14C-labelled substrates, the enzyme seemed to catalyze the condensation of α-ketoglutarate and glyoxylate to form α-hydroxy-β-ketoadipic acid in the presence of thiamine pyrophosphate. α-Hydroxy-β-ketoadipic acid was spontaneously decarboxylated to δ-hydroxylevulinic acid in the presence of acid. 3. 3. The enzyme had an optimum pH of 6.3 in potassium phosphate buffer at 37°. Km values for α-ketoglutarate and glyoxylate were 2.0 mM and 3.2 mM, respectively. The isoelectric point, determined by isoelectric focusing, was 5.6. 4. 4. The enzyme activity was markedly activated by Mn2+ and was activated to a small extent by Mg2+ 5. 5. π-Chloromercuribenzene sulfonic acid, monoiodoacetic acid. EDTA and Zn2+ inhibited the enzyme activity. 6. 6. The purified enzyme catalyzed α-ketoglutarate decarboxylase and α-ketoglutarate:acetaldehyde carboligase activities as well as α-ketoglutarate:glyoxylate carboligase activity. © 1971.