Kleppinger-Sparace K F, Mudd J B
The Plant Cell Research Institute, Dublin, California 94568.
Plant Physiol. 1987 Jul;84(3):682-7. doi: 10.1104/pp.84.3.682.
Intact spinach chloroplasts incorporated (35)SO(4) (2-) into sulfoquinovosyldiacylglycerol in the dark at rates equivalent to those previously reported for illuminated chloroplasts provided that either ATP itself or an ATP-generating system was added. No additional reductant was necessary for SQDG synthesis by chloroplasts. The optimal concentration of ATP was between 2 and 3 millimolar. Rates of synthesis up to 2.6 nanomoles per milligram chlorophyll per hour were observed. UTP, GTP, and CTP could not substitute for ATP. Incubation of UTP with ATP (1:1) stimulated synthesis of sulfoquinovosyldiacylglycerol. No additional stimulation of the reaction was observed upon addition of other nucleoside triphosphates with ATP. For the generation of ATP in the chloroplast, addition of dihydroxyacetone phosphate alone did not promote synthesis of sulfoquinovosyldiacylglycerol, but in combination with inorganic phosphate and oxaloacetate, rates of synthesis up to 3.2 nanomoles per milligram chlorophyll per hour were observed. Dark synthesis was optimal in the presence of 2 millimolar dihydroxyacetone phosphate, 2 millimolar oxaloacetate, and 1 millimolar KH(2)PO(4).
完整的菠菜叶绿体在黑暗中将硫酸根离子（35）SO(4) (2-)掺入磺基喹喔啉二酰基甘油中，掺入速率与之前报道的光照叶绿体的速率相当，前提是添加ATP本身或ATP生成系统。叶绿体合成磺基喹喔啉二酰基甘油不需要额外的还原剂。ATP的最佳浓度在2至3毫摩尔之间。观察到的合成速率高达每毫克叶绿素每小时2.6纳摩尔。UTP、GTP和CTP不能替代ATP。UTP与ATP（1:1）一起孵育会刺激磺基喹喔啉二酰基甘油的合成。在ATP中添加其他核苷三磷酸后，未观察到对该反应的额外刺激。为了在叶绿体中生成ATP，单独添加磷酸二羟丙酮并不能促进磺基喹喔啉二酰基甘油的合成，但与无机磷酸和草酰乙酸结合使用时，观察到的合成速率高达每毫克叶绿素每小时3.2纳摩尔。在存在2毫摩尔磷酸二羟丙酮、2毫摩尔草酰乙酸和1毫摩尔KH(2)PO(4)的情况下，黑暗合成效果最佳。
