Lipoxygenase from baker's yeast: purification and properties.

Lipoxygenase activity was extracted from the mitochondrial fraction of baker's yeast and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column. Two lipoxygenases were eluted from the affinity column. The second enzyme eluted was characterized as a true lipoxygenase. The lipoxygenase eluted showed maximum activity at pH 6.5 with a Km of 2.68 X 10(-4) M on linoleate. The reaction products of the second lipoxygenase with linoleate were characterized by u.v., i.r., NMR spectra and mass spectrometry and were found to be: 9-hydroperoxy-octadeca-trans-10,cis-12-dienoic acid and 13-hydroperoxy-octadeca-cis-9,trans-11-dienoic acid.