Hixon M, Sinerius G, Schneider A, Walter C, Fessner W D, Schloss J V
Department of Medicinal Chemistry, University of Kansas, Lawrence 66045, USA.
FEBS Lett. 1996 Sep 2;392(3):281-4. doi: 10.1016/0014-5793(96)00830-7.
An O2-consuming side reaction of D-ribulose 1,5-bisphosphate carboxylase causes photorespiration in plants. This reaction may be an inevitable consequence of the enzyme's inability to protect its ene-diolate reaction intermediate from O2, a notion that is supported by the failure of persistent efforts to eliminate selectively its oxygenase activity by genetic manipulation. We have examined two a1dolases with similar ene-diolate intermediates, L-rhamnulose 1-phosphate aldolase and L-fuculose 1-phosphate aldolase. The former enzyme has an oxygenase activity, while the latter does not, suggesting that the reaction with O2 is not inevitable.
1,5-二磷酸核酮糖羧化酶的一个消耗氧气的副反应导致了植物的光呼吸作用。这种反应可能是该酶无法保护其烯二醇反应中间体免受氧气影响的必然结果，这一观点得到了以下事实的支持：通过基因操作选择性消除其加氧酶活性的持续努力均告失败。我们研究了两种具有相似烯二醇中间体的醛缩酶，即L-鼠李糖-1-磷酸醛缩酶和L-岩藻糖-1-磷酸醛缩酶。前者具有加氧酶活性，而后者没有，这表明与氧气的反应并非不可避免。
