Copper Acquisition by Methanotrophs.

描述（由申请人提供）：甲烷是美国因人类活动而排放的第二大温室气体。由于甲烷在捕获辐射方面的有效性，它被认为比二氧化碳对环境的危害更大。甲烷氧化菌是革兰氏阴性细菌，代谢甲烷，并可能提供路线的气体修复。在代谢甲烷的第一步，甲烷氧化菌使用一种称为颗粒甲烷单加氧酶（pMMO）的膜蛋白将甲烷氧化为甲醇。pMMO是铜依赖性酶，因此甲烷氧化菌对铜（Cu）的需求升高。在限制铜的条件下，一些甲烷氧化菌分泌一种小的天然产物样分子，以高亲和力结合铜。这种分子被称为甲烷氧化菌素（Mbn）， 其铜负载形式以满足电池的铜需求。拟议的研究将表征涉及在两个不同的甲烷氧化菌的Cu-MBN复合物的再内化的转运蛋白。这项工作将提供洞察甲烷代谢的一个关键要求，收购铜的pMMO的辅因子，是履行的机制。此外，它将提供对甲烷氧化细菌稳态的见解。

DESCRIPTION (provided by applicant): Methane is the second most prevalent greenhouse gas emitted in the United States as a result of human activity. Because of methane's effectiveness at trapping radiation, it is considered significantly more deleterious to the environment than carbon dioxide. Methanotrophs are gram-negative bacteria that metabolize methane and may provide routes for the remediation of the gas. In the first step of metabolizing methane, methanotrophs use an integral membrane protein called particulate methane monooxygenase (pMMO) to oxidize methane to methanol. pMMO is copper-dependent enzyme, and thus methanotrophs have an elevated requirement for copper (Cu). Under conditions of limiting Cu, some methanotrophs secrete a small natural product-like molecule that binds Cu with high affinity. This molecule, called methanobactin (Mbn), is re- internalized into the cell in its Cu-loaded form to satisfy the cell's copper needs. The proposed research will characterize the transporter implicated in the re-internalization of the Cu-Mbn complex in two different methanotrophs. This work will provide insight into the mechanism by which a key requirement for methane metabolism, the acquisition of Cu for pMMO's cofactor, is fulfilled. Additionally, it will provide insight on methanotrophic bacterial homeostasis.