RuBisCO-catalyzed CO2 fixation is the main source of organic carbon in the biosphere. This enzyme is present in all domains of life in different forms (III, II, and I) and its origin goes back to 3500 Mya, when the atmosphere was anoxygenic. However, the RuBisCO active site also catalyzes oxygenation of ribulose 1,5-bisphosphate, therefore, the development of oxygenic photosynthesis and the subsequent oxygen-rich atmosphere promoted the appearance of CO2 concentrating mechanisms (CCMs) and/or the evolution of a more CO2 -specific RuBisCO enzyme. The wide variability in RuBisCO kinetic traits of extant organisms reveals a history of adaptation to the prevailing CO2 /O2 concentrations and the thermal environment throughout evolution. Notable differences in the kinetic parameters are found among the different forms of RuBisCO, but the differences are also associated with the presence and type of CCMs within each form, indicative of co-evolution of RuBisCO and CCMs. Trade-offs between RuBisCO kinetic traits vary among the RuBisCO forms and also among phylogenetic groups within the same form. These results suggest that different biochemical and structural constraints have operated on each type of RuBisCO during evolution, probably reflecting different environmental selective pressures. In a similar way, variations in carbon isotopic fractionation of the enzyme point to significant differences in its relationship to the CO2 specificity among different RuBisCO forms. A deeper knowledge of the natural variability of RuBisCO catalytic traits and the chemical mechanism of RuBisCO carboxylation and oxygenation reactions raises the possibility of finding unrevealed landscapes in RuBisCO evolution.

中文翻译：

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RuBisCO动力学的演化趋势及其与CO2浓缩机制的共同演化。

RuBisCO催化的CO2固定是生物圈中有机碳的主要来源。这种酶以不同的形式（III，II和I）存在于生活的所有域中，其起源可以追溯到3500 Mya，当时大气是无氧的。但是，RuBisCO活性位点也催化核糖1,5-双磷酸酯的氧化，因此，光合作用的发展和随后的富氧气氛促进了CO2浓缩机制（CCM）的出现和/或更多CO2的释放。特异的RuBisCO酶。现存生物的RuBisCO动力学特性差异很大，揭示了在整个进化过程中对主要CO2 / O2浓度和热环境的适应历史。在不同形式的RuBisCO之间发现了动力学参数上的显着差异，但是差异也与每种形式中CCM的存在和类型有关，这表明RuBisCO和CCM共同进化。RuBisCO动力学特性之间的权衡在RuBisCO形式之间以及同一形式内的系统发生群之间也有所不同。这些结果表明，在进化过程中，每种类型的RuBisCO都有不同的生化和结构约束，可能反映了不同的环境选择压力。以类似的方式，酶的碳同位素分馏的变化表明，在不同的RuBisCO形式之间，其与CO2特异性的关系存在显着差异。