title: Marine hydroid perisarc: a chitin- and melanin-reinforced composite with DOPA-iron(III) complexes.
abstract: Many marine invertebrates utilize biomacromolecules as building blocks to form their load-bearing tissues. These polymeric tissues are appealing for their unusual physical and mechanical properties, including high hardness and stiffness, toughness and low density. Here, a marine hydroid perisarc of Aglaophenia latirostris was investigated to understand how nature designs a stiff, tough and lightweight sheathing structure. Chitin, protein and a melanin-like pigment, were found to represent 10, 17 and 60 wt.% of the perisarc, respectively. Interestingly, similar to the adhesive and coating of marine mussel byssus, a DOPA (3,4-dihydroxyphenylalanine) containing protein and iron were detected in the perisarc. Resonance Raman microprobe analysis of perisarc indicates the presence of catechol-iron(III) complexes in situ, but it remains to be determined whether the DOPA-iron(III) interaction plays a cohesive role in holding the protein, chitin and melanin networks together.
authors.affiliation: School of Environmental Science and Engineering, Pohang University of Science and Technology, Pohang 790-784, South Korea. dshwang@postech.ac.kr
authors.forename: Dong Soo
authors.initials: DS
authors.lastname: Hwang
authors.forename: Admir
authors.initials: A
authors.lastname: Masic
authors.forename: Ekavianty
authors.initials: E
authors.lastname: Prajatelistia
authors.forename: Mihaela
authors.initials: M
authors.lastname: Iordachescu
authors.forename: J Herbert
authors.initials: JH
authors.lastname: Waite
mesh_terms: D000818:Animals; D002686:Chitin / Q000032:analysis*; D004295:Dihydroxyphenylalanine / Q000032:analysis*; D006733:Horns / Q000737:chemistry*; D037402:Hydrozoa / Q000737:chemistry*; D007501:Iron / Q000032:analysis*; D008543:Melanins / Q000032:analysis*
chemical_list: D008543:Melanins; D002686:Chitin; D004295:Dihydroxyphenylalanine; D007501:Iron
keywords: Chitin; DOPA; DOPA–iron(III) complex; Hydroid; Perisarc