title: Biochemical analyses of the cement float of the goose barnacle Dosima fascicularis--a preliminary study.
abstract: The goose barnacle Dosima fascicularis produces an excessive amount of adhesive (cement), which has a double function, being used for attachment to various substrata and also as a float (buoy). This paper focuses on the chemical composition of the cement, which has a water content of 92%. Scanning electron microscopy with EDX was used to measure the organic elements C, O and N in the foam-like cement. Vibrational spectroscopy (FTIR, Raman) provided further information about the overall secondary structure, which tended towards a β-sheet. Disulphide bonds could not be detected by Raman spectroscopy. The cystine, methionine, histidine and tryptophan contents were each below 1% in the cement. Analyses of the cement revealed a protein content of 84% and a total carbohydrate content of 1.5% in the dry cement. The amino acid composition, 1D/2D-PAGE and MS/MS sequence analysis revealed a de novo set of peptides/proteins with low homologies with other proteins such as the barnacle cement proteins, largely with an acidic pI between 3.5 and 6.0. The biochemical composition of the cement of D. fascicularis is similar to that of other barnacles, but it shows interesting variations.
authors.affiliation: a University of Vienna, Faculty of Life Sciences, Core Facility Cell Imaging and Ultrastructure Research , Vienna , Austria.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Zheden
authors.forename: Waltraud
authors.initials: W
authors.lastname: Klepal
authors.forename: Janek
authors.initials: J
authors.lastname: von Byern
authors.forename: Fabian Robert
authors.initials: FR
authors.lastname: Bogner
authors.forename: Karsten
authors.initials: K
authors.lastname: Thiel
authors.forename: Thomas
authors.initials: T
authors.lastname: Kowalik
authors.forename: Ingo
authors.initials: I
authors.lastname: Grunwald
mesh_terms: D000269:Adhesives; D000818:Animals; D060829:Arthropod Proteins / Q000032:analysis / Q000737:chemistry*; D003718:Denmark; D008855:Microscopy, Electron, Scanning; D013057:Spectrum Analysis; D001468:Thoracica / Q000737:chemistry*
chemical_list: D000269:Adhesives; D060829:Arthropod Proteins
keywords: 1D/2D PAGE; FTIR/Raman spectroscopy; barnacle adhesive/cement; carbohydrate; hydrogel; protein primary/secondary structure