Patrick Flammang

Université de Mons · Research Institute for Biosciences

Bioluminescence is defined as the production of visible light by a living organism. To fulfil its ecological role (i.e. defense, offense, or communication), bioluminescence needs to be finely controlled. Although nervous or hormonal control mechanisms have been demonstrated to occur , another type of local control via extraocular photo-perception h...

Bioluminescence, the emission of visible light by living organisms, relies on the oxidation of a luciferin substrate catalysed by a luciferase enzyme. This famous terminology may give the false idea that all luminous organisms are using identical or homologous molecular tools to achieve bioluminescence. Instead, multiple light emission systems co‐e...

Quinones are one of the major pigment groups that provide such bright colors to feather stars (Echinodermata, Crinoidea). These secondary metabolites also act as defensive molecules rendering crinoids unpalatable and repellent to other organisms. However, feather stars are usually associated with numerous symbiotic organisms, amongst which the ecto...

Luminous sharks are represented in three families, Etmopteridae, Dalatiidae and Somniosidae. Even structural differences in light organs (i.e. photophores) exist between these shark families, they are small and found in great number mainly on the ventral side. Dalatiidae and Somniosidae harbor photophores constituted of a single photocyte (i.e. lig...

To resist hydrodynamic forces, two main underwater attachment strategies have evolved multiple times in aquatic animals: glue-like “bioadhesive secretions” and pressure-driven “suction attachment”. In this review, we use a multi-level approach to highlight convergence in underwater attachment mechanisms across four different length-scales (organism...

Mutable collagenous tissues (MCTs) from echinoderms (e.g., sea stars, sea urchins) possess the remarkable ability to change their mechanical properties rapidly and reversibly thanks to the release of effector molecules regulating the number of cross-links between collagen fibrils. Among these effector molecules, tensilin has been identified as a st...

Saponins are plant and marine animal specific metabolites that are commonly considered as molecular vectors for chemical defenses against unicellular and pluricellular organisms. Their toxicity is attributed to their membranolytic properties. Modifying the molecular structures of saponins by quantitative and selective chemical reactions is increasi...

Sea urchins possess specialized adhesive organs, tube feet. Although initially believed to function as suckers, it is currently accepted that they rely on adhesive and de-adhesive secretions to attach and detach repeatedly from the substrate. Given the biotechnological potential of their strong reversible adhesive, sea urchins are under investigati...

This review presents a synthesis of shark bioluminescence knowledge. Up to date, bioluminescent sharks are found only in Squaliformes, and specifically in Etmopteridae, Dalatiidae and Somniosidae families. The state-of-the-art knowledge about the evolution, ecological functions, histological structure, the associated squamation and physiological co...

Sea stars can adhere to various underwater substrata using an adhesive secretion of which Sfp1 is a major component. Sfp1 is a multimodular protein composed of four subunits (Sfp1 Alpha, Beta, Delta, and Gamma) displaying different functional domains. We recombinantly produced two fragments of Sfp1 comprising most of its functional domains: the C-t...

Bioluminescence—i.e., the emission of visible light by living organisms—is defined as a biochemical reaction involving, at least, a luciferin substrate, an oxygen derivative, and a specialised luciferase enzyme. In some cases, the enzyme and the substrate are durably associated and form a photoprotein. While this terminology is educatively useful t...

Bioluminescence – i.e., the emission of visible light by living organisms - is defined as a biochemical reaction involving, at least, a luciferin substrate, an oxygen derivative, and a specialised luciferase enzyme. In some cases, the enzyme and the substrate are durably associated and form a photoprotein. While this terminology is educatively usef...

To attach to surfaces in the sea, sea stars produce proteinaceous adhesive secretions. Sfp1 is a major constituent of this adhesive, where it is present in the form of four subunits (named Sfp1α to δ) displaying specific protein-, carbohydrate- and metal-binding domains. Recently, two recombinant proteins inspired from Sfp1 have been produced: one...

In most animals, connective tissues such as the dermis or tendons present invariant mechanical properties, fine-tuned for their structural function. However, echinoderms, a group of sea creatures including sea cucumbers, possess the ability to voluntarily modify the mechanical properties of their connective tissues, which are therefore called mutab...

The cookie-cutter shark Isistius brasiliensis (Squaliformes: Dalatiidae) is a deep-sea species that emits a blue luminescence ventrally, except at the level of a black band located beneath the jaw. This study aims to (i) investigate the distribution and histology of the photophores (i.e., light-emitting organs) along the shark body, (ii) describe t...

Bioluminescence – i.e., the emission of visible light by living organisms - is defined as a biochemical reaction involving, at least, a luciferin substrate, an oxygen derivative, and a specialised luciferase enzyme. In some cases, the enzyme and the substrate are durably associated and form a photoprotein. While this terminology is educatively usef...

Many aquatic invertebrates are associated with surfaces, using adhesives to attach to the substratum for locomotion, prey capture, reproduction, building or defence. Their intriguing and sophisticated biological glues have been the focus of study for decades. In all but a couple of specific taxa, however, the precise mechanisms by which the bioadhe...

In non-model organisms, Next Generation Sequencing (NGS) technology improve our ability to analyze gene expression and identify new genes or transcripts of interest. In this research, paired-end Illumina HiSeq sequencing has been used to describe a composite transcriptome based on two libraries generated from dorsal and ventral integuments of the E...

Aquacultivated sea cucumbers often suffer from SKin Ulceration Diseases (SKUDs). SKUDs have been observed in six holothuroid species from nine countries. All SKUDs present a similar symptom— the skin ulceration—and can be induced by bacteria, viruses, or abiotic factors. We here provide an update on SKUDs in holothuroids and analyse the case of the...

Limpets (Patella vulgata L.) are renowned for their powerful attachments to rocks on wave-swept seashores. Unlike adult barnacles and mussels, limpets do not adhere permanently; instead, they repeatedly transition between long-term adhesion and locomotive adhesion depending on the tide. Recent studies on the adhesive secretions (bio-adhesives) of m...

Sea stars adhere to various underwater substrata using an efficient protein-based adhesive secretion. The protein Sfp1 is a major component of this secretion. In the natural glue, it is cleaved into four subunits (Sfp1 Alpha, Beta, Delta and Gamma) displaying specific domains which mediate protein-protein or protein-carbohydrate interactions. In th...

Mechanical mismatch between soft tissues and hard implants has been a major obstacle in the bionic devices. Whilst there are many examples of coexistence between soft and hard tissues in living organism, relatively little is known of how to overcome mechanical mismatches occurring at the interface. Among various creatures with the mechanically mism...

Biological organisms produce high-performance composite materials, such as bone, wood and insect cuticle, which provide inspiration for the design of novel materials. Ascidians (sea squirts) produce an organic exoskeleton, known as a tunic, which has been studied quite extensively in several species. However, currently, there are still gaps in our...

Saponins are plant secondary metabolites. There are associated with defensive roles due to their cytotoxicity and are active against microorganisms. Saponins are frequently targeted to develop efficient drugs. Plant biomass containing saponins deserves sustained interest to develop high-added value applications. A key issue when considering the use...

Biological organisms produce high-performance composite materials, such as bone, wood and insect cuticle, which provide inspiration for the design of novel materials. Ascidians (sea squirts) produce an organic exoskeleton, known as a tunic, which has been studied quite extensively in several species. However, currently, there are still gaps in our...

Modern mass spectrometry methods provide a huge benefit to saponin structural characterization, especially when combined with collision-induced dissociation experiments to obtain a partial description of the saponin (ion) structure. However, the complete description of the structures of these ubiquitous secondary metabolites remain challenging, esp...

Sea stars use adhesive secretions to attach their numerous tube feet strongly and temporarily to diverse surfaces. After detachment of the tube feet, the adhesive material stays bound to the substrate as so-called ‘footprints’. In the common sea star species Asterias rubens , the adhesive material has been studied extensively and the first sea star...

Ocean warming (OW) and acidification (OA) are intensively investigated as they pose major threats to marine organism. However, little effort is dedicated to another collateral climate change stressor, the increased frequency, and intensity of storm events, here referred to as intensified hydrodynamics. A 2‐month experiment was performed to identify...

Modern mass spectrometry methods provide a huge benefit to saponin structural characterization, especially when combined with collision-induced dissociation experiments to obtain a partial description of the saponin (ion) structure. However, the complete description of the structures of these ubiquitous secondary metabolites remain challenging, esp...

Echinoderms form a remarkable phylum of marine invertebrates that present specific chemical signatures unique in the animal kingdom. It is particularly the case for essential triterpenoids that evolved separately in each of the five echinoderm classes. Indeed, while most animals have ∆ 5-sterols, sea cucumbers (Holothuroidea) and sea stars (Asteroi...

Marine organisms are able to produce light using either their own luminous system, called intrinsic bioluminescence, or symbiotic luminous bacteria, called extrinsic bioluminescence. Among bioluminescent vertebrates, Osteichthyes are known to harbor both types of bioluminescence, while no study has so far addressed the potential use of intrinsic/ex...

The velvet belly lanternshark (Etmopterus spinax) is a small deep-sea shark commonly found in the Eastern Atlantic and the Mediterranean Sea. This bioluminescent species is able to emit a blue-green ventral glow used in counter-illumination camouflage, mainly. In this study, paired-end Illumina HiSeq TM technology has been employed to generate tran...

Sea urchin pigments, also known as spinochromes or polyhydroxynaphthoquinones (PHNQ) have been well studied for their bioactive properties like anti-bacterial, fungicidal, antioxidant and pro-inflammatory effects. Moreover, many studies have analyzed and identified these pigments in sea urchin tests and spines but, and to the best of our knowledge,...

About 64 and 49 million Illumina reads were generated from skin and eye tissues from Etmopterus spinax. The assembly allowed us to predict 119,749 total unigenes including 94,569 for the skin transcriptome and 94,365 for the eye transcriptome while 74,753 were commonly found in both transcriptomes. A taxonomy filtering ("Eukaryotes without plants")...

Many marine invertebrates use adhesive secretions to attach to underwater surfaces and functional groups borne by their adhesive proteins and carbohydrates, such as catechols and phosphates, play a key role in adhesion. The occurrence of sulfates as recurrent moieties in marine bioadhesives suggests that they could also be involved. However, in mos...

Sea urchin pigmentation is mainly due to polyhydroxy-1,4-naphthoquinones called spinochromes. If theirmolecular structures are well known in test and spines of many species, their abundance and distribution in other body compartments remain unstudied. The aim of this study is to analyse the pigment composition in four body compartments (test/spines...

Background: Marine biological adhesives are a promising source of inspiration for biomedical and industrial applications. Nevertheless, natural adhesives and especially temporary adhesion systems are mostly unexplored. Sea stars are able to repeatedly attach and detach their hydraulic tube feet. This ability is based on a duo-gland system and, upon...

Table S1: Overview of lectin binding specificity according to manufacturer Vector laboratories. Figure S1: Antibody labelling of tube foot sections from Asterias rubens (A,C) and Asterina gibbosa (B,D). Antibody directed against Sfp1α (A,B) and Sfp1β (C,D). Scale bars: 20 µm. Figure S2: Lectin labelling of tube foot sections from Asterina gibbosa w...

The velvet belly lantern shark (Etmopterus spinax) is a small deep-sea shark commonly found in the Eastern Atlantic and the Mediterranean Sea. In this study, paired-end Illumina HiSeq(TM) technology has been employed to analyze transcriptome data from eye and ventral skin tissues of the lanternshark species. About 64 and 49 million Illumina reads w...

Rationale Saponins are natural compounds presenting a high structural diversity whose structural characterization remains extremely challenging. Ideally, saponin structures are best established using nuclear magnetic resonance experiments conducted on isolated molecules. However, saponins are also increasingly characterized using tandem mass spectr...

Water motion, because of its potential to dislodge intertidal organisms, plays a crucial role in shaping marine communities as it creates available spaces suitable for interactions, settlement and colonization. To understand how water flow influences the behavioural ecology of benthic species such as echinoids, we investigated how the sea urchin Pa...

Ascidians are deuterostome invertebrates known for their remarkable filtering abilities. Their integument is composed of an epidermis covered by a tunic made up of cellulose nanofibers and secondarily colonized by multiple specific cell types. Using various light and electron microscopy methods, tunic morphology and composition were investigated in...

Bioluminescence relies on the oxidation of a luciferin substrate catalysed by a luciferase enzyme. Numerous light emission systems would have co-emerged independently along the tree of life resulting in a plethora of non-homologous luciferases. We used transcriptome and phylogenomic analyses, immunodetections and electron microscopy to identify the...

This chapter discusses the applicability of different AFM-based techniques with force sensitivity of a few pN for mapping the nanostructure and quantifying the nanoscale mechanical properties of the surface of complex polymer coatings based on silicone oligomers in order to use them as bioadhesives. The AFM modes used are Peak Force Tapping and Con...

Spinochromes are principally known to be involved in sea urchin pigmentation as well as for their potentially interesting pharmacological properties. To assess their biological role in sea urchin physiology, experiments are undertaken on crude extracts from four species and on four isolated spinochromes in order to test their antibacterial, antioxi...

Amphiura filiformis is a common burrowing brittle star from muddy environments along the European shores. This species emits a blue light at the level of the arm spine tips when mechanically stimulated. Although the putative luciferase of A. filiformis was recently discovered, the ultrastructure of the luminous cells, i.e. the photocytes, remain un...

Bioluminescence relies on the oxidation of a luciferin substrate catalysed by a luciferase enzyme. Luciferins and luciferases are generic terms used to describe a large variety of substrates and enzymes. Whereas luciferins can be shared by phylogenetically distant organisms which feed on organisms producing them, luciferases have been thought to be...

Table S1: BLAST searches of known luciferase-like in the arm transcriptome of A. filiformis

Table S3: Reciprocal BLAST results of A. filiformis RLuc-like sequences in NR database (Genbank)

Despite their soft body and slow motion, sea cucumbers present a low predation rate, reflecting the presence of efficient defence systems. For instance, members of the family Holothuriidae rely on Cuvierian tubules for their defence. These tubules are normally stored in the posterior coelomic cavity of the animal, but when the sea cucumber is threa...

Intertidal rocky shores are stressful environments where benthic invertebrates experience large wave-induced hydrodynamic forces that can detach them from the substratum. The tube feet of echinoids counteract these forces and help them remain securely affixed. Sea urchins display a high degree of phenotypic plasticity which may help them cope with...

Saponin analysis by mass spectrometry methods is nowadays progressively supplementing other analytical methods such as nuclear magnetic resonance (NMR). Indeed, saponin extracts from plant or marine animals are often constituted by a complex mixture of (slightly) different saponin molecules that requires extensive purification and separation steps...

Bioluminescence is the oxidation of a luciferin substrate catalysed by a luciferase enzyme. Luciferins and luciferases are generic terms used to describe a large variety of substrates and enzymes. Whereas luciferins can be shared by phylogenetically distant organisms which feed on organisms producing them, luciferases have been thought to be lineag...

Echinoderms are quite exceptional in the sense that most species belonging to this group use adhesive secretions extensively. Two different adhesive systems may be recognised in these animals: the tube feet, organs involved in attachment to the substratum or food capture, and the Cuvierian tubules, organs involved in defence. These two systems rely...