Department of Biology, Emeritus of Friedrich-Alexander University, Möhrendorf, Germany
Anticancer Res. 2022 Oct;42(10):5035-5041. doi: 10.21873/anticanres.16012.
Photosynthesis is the basis of almost all life on Earth. In addition to providing energy, plants and algae provide a plethora of secondary substances useful in the treatment of a number of illnesses including a wide array of cancer maladies. The first organisms on Earth used chemosynthesis for their energy needs. Photosynthetic bacteria utilize one of two different photosystems whereas cyanobacteria, eukaryotic algae and plants combine two photosystems in a linear electron transport chain. Accessory pigments such as various chlorophylls, carotenoids and phycobilins absorb the energy of impinging photons and funnel it to the reaction centers (P680 in photosystem II and P700 in photosystem I). Water is split photochemically, electrons are transported to reduce NADPH, oxygen is discarded as waste product, and protons accumulate inside the thylakoid vesicles in the chloroplasts. The resulting electrochemical gradient across the membrane is used to drive an ATPase. The produced ATP and NADPH+H are utilized in the Calvin cycle to fix CO and to produce fructose.
光合作用是地球上几乎所有生命的基础。除了提供能量外，植物和藻类还提供了大量的次生物质，这些物质在治疗许多疾病方面非常有用，包括广泛的癌症疾病。地球上最早的生物体利用化学生长来满足其能量需求。光合细菌利用两种不同的光合作用系统之一，而蓝细菌、真核藻类和植物则在一个线性电子传递链中结合两个光合作用系统。辅助色素，如各种叶绿素、类胡萝卜素和藻胆素，吸收撞击光子的能量，并将其引导至反应中心（光合作用系统 II 中的 P680 和光合作用系统 I 中的 P700）。水在光化学上分裂，电子被运输以还原 NADPH，氧气作为废物被丢弃，质子在叶绿体的类囊体腔内积累。膜两侧形成的电化学梯度用于驱动 ATP 酶。产生的 ATP 和 NADPH+H 用于卡尔文循环固定 CO 和产生果糖。
