The stalked barnacle <i>Lepas anatifera</i> and its adhesive.

<p>A) aggregation of <i>L. anatifera</i>; B) adhesive plaque of <i>L. anatifera</i> (black arrow) adhered to nylon rope; C) samples from the adhesive plaque of <i>L. anatifera</i>; D) liquid adhesive extracted from beneath the adhesive plaque of <i>L. anatifera</i> (black arrow).</p

Repeating amino acid motifs appearing in fp-1 of various mussel species (family Mytilidae), including several species of the genus <i>Mytilus</i>.

<p>*<i>Perna perna</i> fp-1 is an incomplete sequence and is only assumed to be a repeating motif. Underlined residues have been reported to be post-translationally modified.</p><p>Repeating amino acid motifs appearing in fp-1 of various mussel species (family Mytilidae), including several species of the genus <i>Mytilus</i>.</p

SDS-PAGE adhesive protein separation of five biological replicates (‘samples’) of <i>L. anatifera</i>.

<p>Left hand column is ladder of protein molecular masses. Prominent, repeated bands were observed at approximately 30 kDa, 90 kDa and 110 kDa. Fainter bands were detected at 35 kDa, 40 kDa, 60–68 kDa, 80 kDa, and 130 kD kDa. A band at 70 kDa was sometimes intense and weak at other times.</p

Polyclonal antibody for cp-52k adhesive protein in acorn and stalked barnacles.

<p>A, C & E) <i>A. improvisus</i> (acorn barnacle). B, D & F) <i>Lepas anatifera</i> (stalked barnacle). Insets are negative controls. Ag-adhesive gland, ov-ovarian tubules, PC-principal canal.</p

Similarity of barnacle adhesive cDNA and AA sequences between different species.

<p>Similarity was calculated using GeneDoc <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108902#pone.0108902-Nicholas1" target="_blank">[41]</a>, based on Clustal W alignments created in Mega5 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108902#pone.0108902-Tamura1" target="_blank">[40]</a>. Similarity is calculated for species pairs, so for groups of more than two species a range of similarity is given. Two variants of cp-20k exist in <i>A. amphitrite</i> and both were included in alignments, resulting in a range of similarity values for the cp-20k two species comparison.</p><p>Similarity of barnacle adhesive cDNA and AA sequences between different species.</p

<i>De novo</i> sequences from tryptic peptides of <i>L. anatifera</i> adhesive protein bands (listed along top row), analysed by PEAKS using MALDI-TOF/TOF MS.

<p>Monoisotopic masses of each tryptic peptide are listed in the first column. Sequences found in more than one protein band are underlined.</p><p><i>De novo</i> sequences from tryptic peptides of <i>L. anatifera</i> adhesive protein bands (listed along top row), analysed by PEAKS using MALDI-TOF/TOF MS.</p

Phylogeny of taxonomic orders of barnacle showing approximate time that these taxonomic groups split, based on [64].

<p>The names of the taxonomic orders of barnacle appear on the tree branches; ‘Mya’ =  million years ago.</p

Polyclonal antibody for cp-68k adhesive protein in acorn and stalked barnacles.

<p>A, C & E) <i>A. improvisus</i> (acorn barnacle). B, D & F) <i>Lepas anatifera</i> (stalked barnacle). Insets are negative controls. Ag-adhesive gland ov-ovarian tubules PC-principal canal. Black arrows indicate intensely-stained areas.</p

Extract from clustalW alignment of entire cp-19k genes from <i>M. rosa, A. improvisus</i> and <i>F. albicostatus</i> and EST sequences from <i>P. pollicipes</i>.

<p>Sequence conservation across four species is shown in black and across three species only is shown in grey. Dashed lines show base pairs that are not present in a sequence. Consensus sequence is included as the last line of each row.</p

Protein masses (kDa) of gel bands observed in the polymerised adhesive of <i>L. anatifera</i> (current study) and <i>D. fascicularis</i>; 1: polymerised adhesive [43], 2: partially polymerised adhesive [42], 3: unpolymerised adhesive [42].

<p>See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108902#pone.0108902.s001" target="_blank">Figure S1</a>. An error of 5 kDa was considered for this comparison. The most consistently found bands present in both species are indicated in bold, bands that were consistent within <i>L. anatifera</i> during repeated SDS-PAGE analyses are indicated with *, bands that were weak in <i>L. anatifera</i> adhesive are indicated with ‘w’.</p><p>Protein masses (kDa) of gel bands observed in the polymerised adhesive of <i>L. anatifera</i> (current study) and <i>D. fascicularis</i>; 1: polymerised adhesive <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108902#pone.0108902-Zheden1" target="_blank">[43]</a>, 2: partially polymerised adhesive <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108902#pone.0108902-McEvilly1" target="_blank">[42]</a>, 3: unpolymerised adhesive <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0108902#pone.0108902-McEvilly1" target="_blank">[42]</a>.</p