Purification of a lipoxygenase from ungerminated barley. Characterization and product formation.
Lipoxygenase was purified from ungerminated barley (variety 'Triumph'), yielding an active enzyme with a pI of 5.2 and a molecular mass of approximately 90 kDa. In addition to the 90 kDa band SDS-PAGE showed the presence of two further proteins of 63 kDa. Western blot analysis showed cross-reactivity of each of these proteins with polyclonal antisera against lipoxygenases from pea as well as from soybean, suggesting a close immunological relationship. The 63 kDa proteins appear to be inactive degradation products of the active 90-kDa enzyme. This barley lipoxygenase converts linoleic acid mainly into (9S)-(10E,12Z)-9-hydroperoxy-10,12-octadecadienoic acid, and arachidonic acid into (5S)-(6E,8Z,11Z,14Z)-5-hydroperoxy-6,8,11,14-eic osatetraenoic acid.
van Aarle
P G
PG
Bijvoet Center for Biomolecular Research, Department of Bio-Organic Chemistry, Utrecht University, The Netherlands.
de Barse
M M
MM
Veldink
G A
GA
Vliegenthart
J F
JF
D015153:Blotting, Western; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D001467:Hordeum / Q000201:enzymology*; D015289:Leukotrienes / Q000378:metabolism; D008041:Linoleic Acids / Q000378:metabolism; D008054:Lipid Peroxides / Q000378:metabolism; D008084:Lipoxygenase / Q000737:chemistry / Q000276:immunology / Q000302:isolation & purification*; D008970:Molecular Weight; D013379:Substrate Specificity
D015289:Leukotrienes; D008041:Linoleic Acids; D008054:Lipid Peroxides; C008285:linoleic acid hydroperoxide; C025348:arachidonic acid 5-hydroperoxide; D008084:Lipoxygenase