The sandcastle worm Phragmatopoma californica, a marine polychaete, constructs a tube-like shelter by cementing together sand grains using a glue secreted from the building organ in its thorax. The glue is a mixture of post-translationally modified proteins, notably the cement proteins Pc-1 and Pc-2 with the amino acid, 3,4-dihydroxyphenyl-L-alanine (DOPA). Significant amounts of a halogenated derivative of DOPA were isolated from the worm cement following partial acid hydrolysis and capture of catecholic amino acids by phenylboronate affinity chromatography. Analysis by tandem mass spectrometry and 1H NMR indicates the DOPA derivative to be 2-chloro-4, 5-dihydroxyphenyl-L-alanine. The potential roles of 2-chloro-DOPA in chemical defense and underwater adhesion are considered.

中文翻译：

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海洋粘附蛋白中的卤化多巴

沙堡蠕虫 Phragmatopoma californica 是一种海洋多毛类动物，它通过使用从其胸腔中的建筑器官分泌的胶水将沙粒粘合在一起来建造一个管状庇护所。胶水是翻译后修饰蛋白的混合物，特别是水泥蛋白 Pc-1 和 Pc-2 与氨基酸，3,4-二羟基苯基-L-丙氨酸（DOPA）。在部分酸水解和通过苯基硼酸酯亲和层析捕获儿茶酚氨基酸后，从蠕虫水泥中分离出大量的 DOPA 卤化衍生物。串联质谱和 1 H NMR 分析表明 DOPA 衍生物是 2-氯-4, 5-二羟基苯基-L-丙氨酸。考虑了 2-氯-多巴在化学防御和水下粘附中的潜在作用。