圖1. 於藍藻中，科學家們發現了一種，可能引領出更佳捕獲碳，濳在上能增加糧食產量，並增強氣候適應能力之作物的新酵素功能。

Scientists discover a new enzyme function in cyanobacteria that could lead to better carbon-capturing crops, potentially increasing food production and enhancing climate resilience.

Researchers have uncovered the mechanism of a crucial enzyme, described as “hidden in nature’s blueprint,” illuminating how cells control key processes in carbon fixation, a process fundamental for life on Earth.

研究人員們業已揭露一種闡明，於碳固定中，細胞如何控制地球生命之基本關鍵過程，被記述為“隱藏於大自然藍圖中”之關鍵酶的機制。

The discovery could help engineer climate-resilient crops capable of sucking carbon dioxide from the atmosphere more efficiently, helping to produce more food in the process. The breakthrough was made by scientists from The Australian National University (ANU) and the University of Newcastle (UoN).

此發現可能協助設計出，能更有效從大氣中，吸收二氧化碳，且在此過程中，有助於生產更多糧食之適應氣候的作物。

The research, published on May 10 in the journal Science Advances, demonstrates a previously unknown function of an enzyme called carboxysomal carbonic anhydrase (CsoSCA), which is found in cyanobacteria – also called blue-green algae – to maximize the microorganisms’ ability to extract carbon dioxide from the atmosphere.

這項於(2024年)5月10日，發表於《科學進展》雜誌的研究證實一種，存在於藍細菌(也稱為藍綠藻)中，使該種微生物從大氣中，吸取二氧化碳的能力達最大限度，被稱為羧基體碳酸酐酶(CsoSCA)之酵素，先前未知的功能。

Cyanobacteria are commonly known for their toxic blooms in lakes and rivers. But these little blue-green bugs are widespread, also living in the world’s oceans.

藍細菌以其，在湖泊及河流中，有毒的密集孳生聞名。不過，此些小藍綠菌分佈廣泛，也生存於世界諸海洋中。

Although they can pose an environmental hazard, the researchers describe them as “tiny carbon superheroes.” Through the process of photosynthesis, they play an important role in capturing about 12 percent of the world’s carbon dioxide each year.

雖然，它們會對環境造成危害。不過，此些研究人員將它們描述為“微小的碳超級英雄”。透過光合作用過程，在每年捕獲世界大約12%二氧化碳上，它們扮演一種重要角色。

圖2. 藍細菌是一群光合細菌，通常被稱為“藍綠藻”，雖然它們是原核生物，而不是真正的藻類。這些生物體存在於，從海洋到淡水到裸露岩石的廣泛水生及陸地環境中。藍細菌以其進行生氧的光合作用能力聞名。這意味著，它們類似植物般產生氧氣，作為一種副產品。就地球上的生命而言，此過程至關重要。因為，它對大氣中氧氣的產生，顯著地作出貢獻。

Cyanobacteria are a group of photosynthetic bacteria, often referred to as “blue-green algae,” although they are prokaryotes and not true algae. These organisms are found in a wide range of aquatic and terrestrial environments, from oceans to freshwater to bare rock. Cyanobacteria are known for their ability to perform oxygenic photosynthesis, meaning they produce oxygen as a byproduct, similar to plants. This process is critical for life on Earth as it significantly contributes to the production of oxygen in the atmosphere.

First author and PhD researcher Sacha Pulsford, from ANU, describes how remarkably efficient these microorganisms are at capturing carbon.

來自澳洲國立大學(ANU：Australian National University)的首要撰文人、博士研究員，Sacha Pulsford描述了，在捕獲碳方面，此些微生物如何顯著有效率。

“Unlike plants, cyanobacteria have a system called a carbon dioxide concentrating mechanism (CCM), which allows them to fix carbon from the atmosphere and turn it into sugars at a significantly faster rate than standard plants and crop species,” Ms. Pulsford said.

Pulsford先生宣稱：「不像植物，藍細菌具有一種，使它們能以顯著比標準植物及作物種類更快的速度，固定來自大氣的碳，並將其轉化為糖，被稱為二氧化碳濃縮機制(CCM)的系統。」

At the heart of the CCM are large protein compartments called carboxysomes. These structures are responsible for sequestering carbon dioxide, housing CsoSCA and another enzyme called Rubisco.

在CCM的核心是，被稱為羧基體的大蛋白質分室。此些結構負責隔離二氧化碳、貯藏CsoSCA及另一種，被稱為Rubisco的酵素。

The enzymes CsoSCA and Rubisco work in unison, demonstrating the highly efficient nature of the CCM. The CsoSCA works to create a high local concentration of carbon dioxide inside the carboxysome that Rubisco can then gobble up and turn into sugars for the cell to eat.

CsoSCA及Rubisco酶共同運作，證實了CCM的高效率性質。CsoSCA運作，來在之後於羧基體內部產生，Rubisco能吞噬並轉化為糖，供細胞消耗的局部高濃度二氧化碳。

Lead author Dr. Ben Long, from UoN, said: “Until now, scientists were unsure how the CsoSCA enzyme is controlled. Our study focused on unraveling this mystery, particularly in a major group of cyanobacteria found across the globe. What we found was completely unexpected.

來自英國北安普敦大學(UoN：University of Northampton)的首要撰文人，Ben Long博士宣稱：「到目前為止，科學家們並不確定，CsoSCA酶如何受控制。我們的研究著重於，解開此謎團。特別是，在世界各地被發現的大群藍細菌。我們所發現的，是完全沒意料到的事。

“The CsoSCA enzyme dances to the tune of another molecule called RuBP, which activates it like a switch.

CsoSCA酶隨著另一種，如開關般激活它，被稱為RuBP之分子的節奏起舞。

“Think of photosynthesis like making a sandwich. Carbon dioxide from the air is the filling, but a photosynthetic cell needs to provide the bread. That’s RuBP.

將光合作用想像如製做三明治。來自空氣中的二氧化碳是餡。不過，光合細胞需要提供麵包。那就是RuBP。

“Just like you need bread to make a sandwich, the rate of turning carbon dioxide into sugar depends on how fast RuBP is supplied.

就如同需要麵包來製作三明治般，將二氧化碳轉化為糖的速度，取決於供應RuBP的速度有多快。

“How fast the CsoSCA enzyme supplies carbon dioxide to Rubisco is dependent on how much RuBP is present. When there’s enough, the enzyme is switched on. But if the cell runs out of RuBP, the enzyme is switched off, making the system highly tuned and efficient.

CsoSCA酵素提供Rubisco二氧化碳有多快，取決於存在多少RuBP。當有足夠的量時，該酵素被開啟。不過，倘若細胞耗盡RuBP，該酵素被關閉，使得此體系是高度協調且高效率的。

“Surprisingly, the CsoSCA enzyme has been embedded in nature’s blueprint all along, waiting to be discovered.”

令人驚訝的是，CsoSCA酶一直被嵌於大自然的藍圖中，等待被發現。」

The scientists say engineering crops that are more efficient at capturing and utilizing carbon dioxide would provide a huge boost for the agricultural industry by vastly improving crop yield while reducing the demand for nitrogen fertilizer and irrigation systems.

此些科學家表示，在捕獲及利用二氧化碳更有效之工程改造的作物，藉由大幅改善作物產量，同時減少對氮肥及灌溉系統的需求，將為農業之產業提供巨大的推動力。

It would also ensure the world’s food systems are more resilient to climate change.

這也將確保，世界的糧食體系更能適應氣候變遷。

Ms Pulsford said: “Understanding how the CCM works not only enriches our knowledge of natural processes fundamental to Earth’s biogeochemistry but may also guide us in creating sustainable solutions to some of the biggest environmental challenges the world is facing.”

Pulsford先生宣稱：「瞭解CCM如何運作，不僅豐富了我們，有關地球生物化學之基礎自然過程的知識，而且也可能引導我們，為世界正面臨的諸多最大環境挑戰，設計可持續的解決方案。」

網址：https://scitechdaily.com/scientists-supercharge-photosynthesis-to-develop-carbon-gobbling-super-plants/

翻譯：許東榮