carboxyl group

例句：

1. 1. The enzyme catalyzes the reaction by breaking down the carbon dioxide and releasing hydrogen ions.
   这种酶通过分解二氧化碳并释放氢离子来催化反应。
2. 2. The amino acid is a building block for proteins.
   这种氨基酸是蛋白质的构建块。
3. 3. The carboxyl group in the compound reacts with the metal to form a complex.
   化合物中的羧基团与金属反应形成络合物。