Peroxisomal enzyme activities in attached senescing leaves.
Maneno muhimu
Kikemikali
Recently it has been demonstrated that detached leaves show glyoxysomal enzyme activities when incubated in darkness for several days. In this report glyoxylate-cycle enzymes have been detected in leaves of rice (Oryza sativa L.) and wheat (Triticum durum L.) from either naturally senescing or dark-treated plants. Isolated peroxisomes of rice and wheat show isocitrate lyase (EC 4.1.3.1), malate synthase (EC 4.1.3.2) and β-oxidation activities. Leaf peroxisomes from dark-induced senescing leaves show glyoxylic-acid-cycle enzyme activities two to four times higher than naturally senescing leaves. The glyoxysomal activities detected in leaf peroxisomes during natural foliar senescence may represent a reverse transition of the peroxisomes into glyoxysomes.