Barnacles interest the scientific community for multiple reasons: their unique evolutionary trajectory, vast diversity and economic impact—as a harvested food source and also as one of the most prolific macroscopic hard biofouling organisms. A common, yet novel, trait among barnacles is adhesion, which has enabled a sessile adult existence and global colonization of the oceans. Barnacle adhesive is primarily composed of proteins, but knowledge of how the adhesive proteome varies across the tree of life is unknown due to a lack of genomic information. Here, we supplement previous mass spectrometry analyses of barnacle adhesive with recently sequenced genomes to compare the adhesive proteomes of Pollicipes pollicipes (Pedunculata) and Amphibalanus amphitrite (Sessilia). Although both species contain the same broad protein categories, we detail differences that exist between these species. The barnacle-unique cement proteins show the greatest difference between species, although these differences are diminished when amino acid composition and glycosylation potential are considered. By performing an in-depth comparison of the adhesive proteomes of these distantly related barnacle species, we show their similarities and provide a roadmap for future studies examining sequence-specific differences to identify the proteins responsible for functional differences across the barnacle tree of life.

藤壶引起科学界的兴趣有多种原因：它们独特的进化轨迹、巨大的多样性和经济影响——作为收获的食物来源，也是最多产的宏观硬生物污染生物之一。藤壶中一个常见但新颖的特征是粘附，这使得它们能够固着地存在并在全球范围内殖民海洋。藤壶粘合剂主要由蛋白质组成，但由于缺乏基因组信息，关于粘合剂蛋白质组如何在生命之树中变化的知识尚不清楚。在这里，我们用最近测序的基因组补充了以前对藤壶粘合剂的质谱分析，以比较Pollicipes pollicipes (Pedunculata) 和Amphibalanus amphitrite 的粘合剂蛋白质组（塞西利亚）。尽管这两个物种都包含相同的广泛蛋白质类别，但我们详细说明了这些物种之间存在的差异。藤壶特有的水泥蛋白在物种之间表现出最大的差异，尽管当考虑氨基酸组成和糖基化潜力时，这些差异会减少。通过对这些远亲藤壶物种的粘性蛋白质组进行深入比较，我们展示了它们的相似性，并为未来研究检查序列特异性差异以识别导致藤壶生命树功能差异的蛋白质提供了路线图。