Photosynthetic dinoflagellates are ecologically and biogeochemically important in marine and freshwater environments. However, surprisingly little is known of how this group acquires inorganic carbon or how these diverse processes evolved. Consequently, how CO₂ availability ultimately influences the success of dinoflagellates over space and time remains poorly resolved compared to other microalgal groups. Here we review the evidence. Photosynthetic core dinoflagellates have a Form II RuBisCO (replaced by Form IB or Form ID in derived dinoflagellates). The in vitro kinetics of the Form II RuBisCO from dinoflagellates are largely unknown, but dinoflagellates with Form II (and other) RuBisCOs have inorganic carbon concentrating mechanisms (CCMs), as indicated by in vivo internal inorganic C accumulation and affinity for external inorganic C. However, the location of the membrane(s) at which the essential active transport component(s) of the CCM occur(s) is (are) unresolved; isolation and characterization of functionally competent chloroplasts would help in this respect. Endosymbiotic Symbiodiniaceae (in Foraminifera, Acantharia, Radiolaria, Ciliata, Porifera, Acoela, Cnidaria, and Mollusca) obtain inorganic C by transport from seawater through host tissue. In corals this transport apparently provides an inorganic C concentration around the photobiont that obviates the need for photobiont CCM. This is not the case for tridacnid bivalves, medusae, or, possibly, Foraminifera. Overcoming these long‐standing knowledge gaps relies on technical advances (e.g., the in vitro kinetics of Form II RuBisCO) that can functionally track the fate of inorganic C forms.

中文翻译：

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自由生活和共生的鞭毛藻和亚纲鞭毛虫中的无机碳浓缩机制。

在海洋和淡水环境中，光合作用鞭毛藻在生态和生物地球化学上都很重要。然而，令人惊讶的是，人们对这一群体如何获取无机碳或这些不同的过程如何演化知之甚少。因此，CO ₂如何可用性最终影响了鞭毛藻在空间上的成功，与其他微藻类相比，时间仍然难以解决。在这里，我们回顾证据。光合核心鞭毛鞭毛藻具有II型RuBisCO（在衍生的鞭毛鞭毛藻中被IB型或ID替代）。来自鞭毛鞭毛虫的II型RuBisCO的体外动力学在很大程度上是未知的，但是具有II型（和其他）RuBisCO的鞭毛鞭虫具有无机碳富集机制（CCM），如体内内部无机C的积累和对外部无机C的亲和力所表明的那样。然而，尚未解决CCM的基本活性转运成分发生的膜的位置。具有功能能力的叶绿体的分离和表征将在这方面有所帮助。内生共生共生菌（在有孔虫科，棘皮科，放射虫科，纤毛科，毛虫科，阿科埃拉科，刺柏科和软体动物中）通过从海水中迁移穿过宿主组织而获得无机碳。在珊瑚中，这种转运显然在光生物体周围提供了无机C浓度，从而消除了对光生物体CCM的需要。Tridacnid双壳类，水母或有孔虫则不是这种情况。克服这些长期存在的知识鸿沟依赖于技术上的进步（例如，II型RuBisCO的体外动力学），可以在功能上追踪无机C形式的命运。在珊瑚中，这种转运显然在光生物体周围提供了无机C浓度，从而消除了对光生物体CCM的需要。Tridacnid双壳类，水母或有孔虫则不是这种情况。克服这些长期存在的知识鸿沟依赖于技术上的进步（例如，II型RuBisCO的体外动力学），可以在功能上追踪无机C形式的命运。在珊瑚中，这种转运显然在光生物体周围提供了无机C浓度，从而消除了对光生物体CCM的需要。Tridacnid双壳类，水母或有孔虫则不是这种情况。克服这些长期存在的知识鸿沟依赖于技术上的进步（例如，II型RuBisCO的体外动力学），可以在功能上追踪无机C形式的命运。