The nature and role of pigments of marine invertebrates

Abstract

Marine animals, especially those from tropical waters, are often brilliantly coloured, and bright colouration is widespread in both sessile and non-sessile invertebrates. These spectacular natural colours are common in species inhabiting shallow waters, and appear not only in animals exposed to bright light, but also in those living in dark areas where colours are visible only with artificial illumination. Marine organisms also show variation in colour with depth and geographical location, and display great variety in colour patterning. These colour characteristics are the result of several different processes, and serve various purposes - the distribution and function of pigments seems to vary between invertebrate groups. In addition to playing an important role in how marine organisms interact, pigments may be involved in physiological processes. Although nitrogenous pigments predominate, marine organisms contain pigments belonging to all the major structural classes of natural products, as well as some that are unique to the marine environment. This review discusses the nature and significance of such pigments, the chemical and biological processes involved, the factors responsible for and affecting bright colourations, as well as their evolution and speculation as to their function.

Coral Fluorescent Proteins as Antioxidants

“…Invertebrate pigments include small molecules such as carotenoids [3], [4], insoluble polymers such as melanin [5], [6], [7], or proteins such as those involved in bioluminescence and fluorescence [8] . Corals are renowned for their vivid coloration [9], [10], for which fluorescent proteins (FPs) are largely responsible [8]. FPs are abundant and diverse within anthozoans, ranging across four basic color types; cyan (CFP), green (GFP), red (RFP) and a blue/purple non-fluorescent chromoprotein [11], [12], [13], however their function within the holobiont remains undetermined and controversial [14], [15].…”

Pigmentation and Spectral Absorbance Signatures in Deep-Water Corals from the Trondheimsfjord, Norway

“…However, it most likely contains astaxanthin, as peaks in its HPLC chromatogram appear at the same retention time as the peaks in the HPLC chromatograms of the other species studied, and the corresponding OD spectra have the same absorption characteristics. Bandaranayake (2006) [16] points out astaxanthin to be the major carotenoid in marine invertebrates, and astaxanthin in L. pertusa , P. arborea and P. resedaeformis has already been confirmed by Upadhyay and Liaaen-Jensen (1970) [30]. …”

“…They are azooxanthellate organisms [1,15] living primarily below the euphotic zone, yet many of these organisms are as intensely colored as tropical corals. Color is defined as the reflection of different wavelengths of visible light, hence coloration is the result of selective absorption [16]. Lophelia pertusa has two basic color morphologies; orange and white [17].…”

“…One of the major carotenoids found in marine invertebrates is astaxanthin [16,26]. Since animals are unable to synthesize carotenoids de novo [27] they obtain these pigments from their diet, i.e.…”

Identification of Tight-Binding Plasmepsin II and Falcipain 2 Inhibitors in Aqueous Extracts of Marine Invertebrates by the Combination of Enzymatic and Interaction-Based Assays

“…At the final dilution of 1/5 and 1/10, the vast majority of the extracts were able to quench the fluorescence of AMC independently of the clarification treatment (data not shown); probably due to the presence of pigments in the extracts [55]. Since this would cause an artificial decrease in the slope of enzymatic assay (mimicking the presence of a true inhibitor), it was necessary to use a final dilution (1/20) in the enzymatic assay such that the fluorescence quenching was not significant ( Q = F AMC / F AMC+EXT ≈ 1) (Figure 2C).…”