Levuglandin E2 (LGE2), a gamma-ketoaldehyde produced by rearrangement of the prostaglandin endoperoxide PGH2 under the aqueous conditions of its biosynthesis, causes extensive intermolecular crosslinking of ovalbumin at pH 6 or pH 7 and 37 degrees C. The time dependence of protein oligomerization is monitored by SDS-PAGE. Effects of pH and concentration on the extent of LGE2-induced crosslinking are examined. The efficacy of LGE2 for inducing crosslinking is compared with other oxidative metabolites of arachidonic acid (AA), including the prostaglandins PGE2, PGD2, PGA2, PGB2, and PGF2 alpha, as well as malondialdehyde and E-4-hydroxy-non-2-enal. LGE2 is orders of magnitude more effective in crosslinking protein than any other cyclooxygenase or lipoxygenase metabolite of AA tested.