L-Lysine: 2-Oxoglutarate 6-Aminotransferase

L-Lysine:2-oxoglutarate 6-aminotransferase from Flavobacterium lutescence (=Achromobacter liquidum)2 has been shown to be composed of one each of four non-identical subunits, A, B1, B2, and C. The subunits were isolated by gel filtration, and DEAE-cellulose chromatography in the presence of 8 M urea. Their molecular weights were determined by ultracentrifugation, gel electrophoresis and gel filtration: subunit A 24,000; B1 28,000; B2, 28,000; C 45,000. These subunits were all different in amino acid composition. Of the two molecules of bound pyridoxal 5′-phosphate, the one which absorbs at 415 nm is bound to subunit B2 and participates in the catalytic action of the enzyme.