Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, South Korea.
Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, South Korea.
Bioresour Technol. 2024 Aug;405:130931. doi: 10.1016/j.biortech.2024.130931. Epub 2024 Jun 4.
Methane (CH) and carbon dioxide (CO) are the dominant greenhouse gases (GHGs) that are increasing at an alarming rate. Methanotrophs have emerged as potential CH and CO biorefineries. This study demonstrated the synchronous incorporation of CH and CO into polyhydroxybutyrate (PHB) for the first time using C-labeling experiments in methanotrophs. By supplying substantial amounts of CO, PHB content was enhanced in all investigated type II methanotrophic strains by 140 %, 146 %, and 162 %. The highest content of PHB from CH and CO in flask-scale cultivation reached 38 % dry cell weight in Methylocystis sp. MJC1, in which carbon percentage in PHB from CO was 45 %. Flux balance analysis predicted the critical roles of crotonyl-CoA carboxylase/reductase and phosphoenolpyruvate carboxylase in CO recycling. This study provided proof of the conversion of GHGs into a valuable and practical product using methanotrophic bacteria, contributing to addressing GHG emissions.
甲烷（CH）和二氧化碳（CO）是主要的温室气体（GHG），它们的排放量正以惊人的速度增长。甲烷氧化菌已成为 CH 和 CO 的潜在生物炼制厂。本研究首次通过甲烷氧化菌的 C 标记实验，证明了 CH 和 CO 的同步掺入聚羟基丁酸酯（PHB）中。通过提供大量的 CO，所有研究的 II 型甲烷氧化菌菌株的 PHB 含量都提高了 140%、146%和 162%。在摇瓶培养中，Methylocystis sp. MJC1 中 CH 和 CO 产生的 PHB 含量最高，达到 38%干重，其中 PHB 中 CO 的碳百分比为 45%。通量平衡分析预测了丙二酰辅酶 A 羧化酶/还原酶和磷酸烯醇丙酮酸羧化酶在 CO 循环中的关键作用。本研究提供了使用甲烷氧化菌将温室气体转化为有价值和实用产品的证据，有助于解决温室气体排放问题。
