Sphingophosphonolipids, phospholipids, and fatty acids from Aegean jellyfish Aurelia aurita

Coral Lipids

Reef-building corals, recognized as cornerstone species in marine ecosystems, captivate with their unique duality as both symbiotic partners and autotrophic entities. Beyond their ecological prominence, these corals produce a diverse array of secondary metabolites, many of which are poised to revolutionize the domains of pharmacology and medicine. This exhaustive review delves deeply into the multifaceted world of coral-derived lipids, highlighting both ubiquitous and rare forms. Within this spectrum, we navigate through a myriad of fatty acids and their acyl derivatives, encompassing waxes, sterol esters, triacylglycerols, mono-akyl-diacylglycerols, and an array of polar lipids such as betaine lipids, glycolipids, sphingolipids, phospholipids, and phosphonolipids. We offer a comprehensive exploration of the intricate biochemical variety of these lipids, related fatty acids, prostaglandins, and both cyclic and acyclic oxilipins. Additionally, the review provides insights into the chemotaxonomy of these compounds, illuminating the fatty acid synthesis routes inherent in corals. Of particular interest is the symbiotic bond many coral species nurture with dinoflagellates from the Symbiodinium group; their lipid and fatty acid profiles are also detailed in this discourse. This exploration accentuates the vast potential and intricacy of coral lipids and underscores their profound relevance in scientific endeavors.

Transcriptomic-Guided Phosphonate Utilization Analysis Unveils Evidence of Clathrin-Mediated Endocytosis and Phospholipid Synthesis in the Model Diatom, Phaeodactylum tricornutum

Phosphonates are important components of marine organic phosphorus, but their bioavailability and catabolism by eukaryotic phytoplankton remain enigmatic. Here, diatom Phaeodactylum tricornutum was used to investigate the bioavailability of phosphonates and describe the underlying molecular mechanism. The results showed that 2-aminoethylphosphonic acid (2-AEP) can be utilized as an alternative phosphorus source. Comparative transcriptomics revealed that the utilization of 2-AEP comprised 2 steps, including molecular uptake through clathrin-mediated endocytosis and incorporation into the membrane phospholipids in the form of diacylglyceryl-2-AEP (DAG-2-AEP). In the global ocean, we found the prevalence and dynamic expression pattern of key genes that are responsible for vesicle formation (CLTC, AP-2) and DAG-AEP synthesis (PCYT2, EPT1) in diatom assemblages. This study elucidates a distinctive mechanism of phosphonate utilization by diatoms, and discusses the ecological implications. IMPORTANCE Phosphonates contribute ~25% of total dissolved organic phosphorus in the ocean, and are found to be important for marine phosphorus biogeochemical cycle. As a type of biogenic phosphonate produced by microorganisms, 2-aminoethylphosphonic acid (2-AEP) widely exists in the ocean. It is well known that 2-AEP can be cleaved and utilized by prokaryotes, but its ability to support the growth of eukaryotic phytoplankton remains unclear. Our research identified the bioavailability of 2-AEP for the diatom Phaeodactylum tricornutum, and proposed a distinctive metabolic pathway of 2-AEP utilization. Different from the enzymatic hydrolysis of phosphonates, the results suggested that P. tricornutum utilizes 2-AEP by incorporating it into phospholipid instead of cleaving the C-P bond. Moreover, the ubiquitous distribution of associated representative gene transcripts in the environmental assemblages and the higher gene transcript abundance in the cold regions were observed, which suggests the possible environmental adaption of 2-AEP utilization by diatoms.

Jellyfish from Fisheries By-Catches as a Sustainable Source of High-Value Compounds with Biotechnological Applications

The world’s population growth and consequent increased demand for food, energy and materials together with the decrease of some natural resources have highlighted the compelling need to use sustainably existing resources and find alternative sources to satisfy the needs of growing and longer-aging populations. In this review, we explore the potential use of a specific fisheries by-catch, jellyfish, as a sustainable source of high-value compounds. Jellyfish are often caught up with fish into fishing gear and nets, then sorted and discarded. Conversely, we suggest that this by-catch may be used to obtain food, nutraceutical products, collagen, toxins and fluorescent compounds to be used for biomedical applications and mucus for biomaterials. These applications are based on studies which indicate the feasibility of using jellyfish for biotechnology. Because jellyfish exhibit seasonal fluctuations in abundance, jellyfish by-catches likely follow the same pattern. Therefore, this resource may not be constantly available throughout the year, so the exploitation of the variable abundances needs to be optimized. Despite the lack of data about jellyfish by-catches, the high value of their compounds and their wide range of applications suggest that jellyfish by-catches are a resource which is discarded at present, but needs to be re-evaluated for exploitation within the context of a circular economy in the era of zero waste.

Biotechnological Applications of Scyphomedusae

As people across the world live longer, chronic illness and diminished well-being are becoming major global public health challenges. Marine biotechnology may help overcome some of these challenges by developing new products and know-how derived from marine organisms. While some products from marine organisms such as microalgae, sponges, and fish have already found biotechnological applications, jellyfish have received little attention as a potential source of bioactive compounds. Nevertheless, recent studies have highlighted that scyphomedusae (Cnidaria, Scyphozoa) synthesise at least three main categories of compounds that may find biotechnological applications: collagen, fatty acids and components of crude venom. We review what is known about these compounds in scyphomedusae and their current biotechnological applications, which falls mainly into four categories of products: nutraceuticals, cosmeceuticals, biomedicals, and biomaterials. By defining the state of the art of biotechnological applications in scyphomedusae, we intend to promote the use of these bioactive compounds to increase the health and well-being of future societies.

Rapid Characterization of Chemical Components in Edible Mushroom Sparassis crispa by UPLC-Orbitrap MS Analysis and Potential Inhibitory Effects on Allergic Rhinitis

Sparassis crispa is a kind of edible fungus widely grows in the north temperate zone, which shows various medicinal properties. Due to the complexity of chemical constitutes of this species, few investigations have acquired a comprehensive configuration for the chemical profile of it. In this study, a strategy based on ultra-high performance liquid chromatography (UPLC) combined with Orbitrap mass spectrometer (MS) was established for rapidly characterizing various chemical components in S. crispa. Through the summarized MS/MS fragmentation patterns of reference compounds and systematic identification strategy, a total of 110 components attributed to six categories were identified for the first time. Moreover, allergic rhinitis (AR) is a worldwide inflammatory disease seriously affecting human health, and the development of drugs to treat AR has been a topic of interest. It has been reported that the extracts of S. crispa showed obvious inhibitory effects on degranulation of mast cell- and allergen-induced IgE and proinflammatory mediators, but the active components and specific mechanism were still not clear. Src family kinases (SFKs) participate in the initial stage of allergy occurrence, which are considered the targets of AR treatment. Herein, on the basis of that self-built chemical database, virtual screening was applied to predict the potential SFKs inhibitors in S. crispa, using known crystal structures of Hck, Lyn, Fyn, and Syk as receptors, followed by the anti-inflammatory activity evaluation for screened hits by intracellular calcium mobilization assay. As results, sparoside A was directly confirmed to have strong anti-inflammatory activity with an IC50 value of 5.06 ± 0.60 μM. This study provides a useful elucidation for the chemical composition of S. crispa, and demonstrated its potential inhibitory effects on AR, which could promote the research and development of effective agents from natural resources.

Lipid Profile in Different Parts of Edible Jellyfish Rhopilema esculentum

Jellyfish Rhopilema esculentum has been exploited commercially as a delicious food for a long time. Although the edible and medicinal values of R. esculentum have gained extensive attention, the effects of lipids on its nutritional value have rarely been reported. In the present of study, the lipid profile including lipid classes, fatty acyl compositions, and fatty acid (FA) positions in lipids from different parts (oral arms, umbrella, and mouth stalk) of R. esculentum was explored by ultraperformance liquid chromatography--electrospray ionization--quadrupole time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS). More than 87 species from 10 major lipid classes including phosphatidylcholine (PC), lysophosphatidylcholine (LPC), phosphatidylethanolamine (PE), lysophosphatidylethanolamine (LPE), phosphatidylinositol (PI), lysophosphatidylinositol (LPI), phosphatidylserine (PS), ceramide (Cer), ceramide 2-aminoethylphosphonate (CAEP), and triacylglycerol (TAG) were separated and characterized. Semiquantification of individual lipid species in different parts of R. esculentum was also conducted. Results showed that glycerophospholipids (GPLs) enriched in highly unsaturated fatty acids (HUFAs) were the major compenents in all parts of R. esculentum, which accounted for 54-63% of total lipids (TLs). Considering the high level of GPLs and the FA compositions in GPLs, jellyfish R. esculentum might have great potential as a health-promoting food for humans and as a growth-promoting diet for some commercial fish and crustaceans. Meanwhile, LPC, LPE, and LPI showed high levels in oral arms when compared with umbrella and mouth stalk, which may be due to the high proportion of phospholipase A2 (PLA2) in oral arms. Moreover, a high CAEP level was detected in oral arms, which may render cell membranes with resistance to chemical hydrolysis by PLA2. The relatively low TAG content could be associated with specific functions of oral arms.

2-Aminoethylphosphonate utilization by the cold-adapted Geomyces pannorum P11 strain

Cold-adapted strain of Geomyces pannorum P11 was found to mineralize of phosphorus–carbon bond-containing compound—2-aminoethylphosphonic acid (2-AEP, ciliatine). The biodegradation process proceeded in the phosphate-independent manner. Ciliatine-metabolizing enzymes' activity was detectable in cell-free extracts prepared from psychrophilic G. pannorum pregrown on 4 mM 2-AEP. Phosphonoacetaldehyde hydrolase (phosphonatase) activity in a partially purified extract was demonstrated at 10 °C.

Mediterranean jellyfish venoms: a review on scyphomedusae

The production of natural toxins is an interesting aspect, which characterizes the physiology and the ecology of a number of marine species that use them for defence/offence purposes. Cnidarians are of particular concern from this point of view; their venoms are contained in specialized structures--the nematocysts--which, after mechanical or chemical stimulation, inject the venom in the prey or in the attacker. Cnidarian stinging is a serious health problem for humans in the zones where extremely venomous jellyfish or anemones are common, such as in temperate and tropical oceanic waters and particularly along several Pacific coasts, and severe cases of envenomation, including also lethal cases mainly induced by cubomedusae, were reported. On the contrary, in the Mediterranean region the problem of jellyfish stings is quite modest, even though they can have anyhow an impact on public health and be of importance from the ecological and economic point of view owing to the implications on ecosystems and on some human activities such as tourism, bathing and fishing. This paper reviews the knowledge about the various aspects related to the occurrence and the stinging of the Mediterranean scyphozoan jellyfish as well as the activity of their venoms.

Coordinated regulation of cold-induced changes in fatty acids with cardiolipin and phosphatidylglycerol composition among phospholipid species for the food pathogen Listeria monocytogenes

We present here the structural identification of four phospholipid (Phl) classes in Listeria monocytogenes, the fatty acid (FA) composition for each individual Phl species, and a description of cold-induced FA changes. Cardiolipin (48.5%) and phosphatidylglycerol (18.1%) are dominated by anteiso-FA, and the previously recognized branched FA chain shortening by cold was observed singularly in these Phls. Phosploaminolipid (19.9%) and phosphatidylinositol, (9.1%) are significantly different, containing significant amounts of straight-chain FA. These findings are supported by nuclear magnetic resonance analysis.

Bacteriovorax stolpii proliferation and predation without sphingophosphonolipids

Bacteriovorax stolpii strain UKi2, a facultative predator-parasite of larger Gram-negative bacteria, synthesizes distinct sphingophosphonolipids. These lipids are characterized by a direct P-C bond, the novel head group 1-hydroxy-2-aminoethylphosphonate, iso-branched long chain bases and fatty acids, and fatty acids dominated by those with alpha-hydroxy groups. Myriocin, an inhibitor of serine:fatty acyl CoA transferase, reversibly blocked sphingophosphonolipid synthesis in B. stolpii UKi2. However, the inhibitor did not block cell proliferation indicating that these lipids are not vital for B. stolpii UKi2 viability and growth. When mixed with Escherichia coli prey cells, control predator-parasite bacteria were effective in forming large E. coli bdelloplasts and cleared the suspension of the prey cells. Although myriocin-treated cells could attack prey cells and form bdelloplasts, their locomotory behavior was altered and fewer and smaller bdelloplasts were produced. These observations open up the possibility for a role of sphingophosphonolipids in B. stolpii UKi2 complex behavior.

Glyco- and sphingophosphonolipids from the medusa Phyllorhiza punctata: NMR and ESI-MS/MS fingerprints

The medusa Phyllorhiza punctata has been found in Brazilian waters where it is an exotic species, having arrived in ballasts from the Indo-Pacific Ocean in the general region of North Australia and Indonesia. Fatty acids of the intact animal and its component umbrella, oral arms, and mucus were identified. Two different groups of glycolipids and a sphingolipid were isolated by silica-gel column chromatography and characterized using GC-MS, ESI-MS, 1D, 2D (13)C, (1)H and (31)P NMR spectroscopy. They were sulfoquinovosyldiacylglycerol (SQDG), monogalactosyldiacylglycerol (MGDG), and ceramide aminoethylphosphonate (CAEP). The CAEP long chain base (LCB) and its polar head group (PHG) formed by partial hydrolysis, were analyzed by ESI-MS/MS. The probable origin of MGDG and SQDG in the jellyfish is the result of an endosymbiotic association with a microalga of the Dinoflagellate group, since these lipids are commonly found in photosynthetic membranes.

Effect of cold temperature on the composition of different lipid classes of the foodborne pathogen Listeria monocytogenes: focus on neutral lipids

In this work a thorough consideration of the membrane lipid composition of Listeria monocytogenes together with DSC analysis is described in order to estimate the biological importance of lipid changes during low-temperature adaptation. Furthermore, these studies provide comparative data for fatty acid changes for neutral, NL and polar lipids, PL separately. The cold adaptation (5 degrees C) response of L. monocytogenes showed (i) an increase in the level of NL content (30%) among the total lipids, TL and (ii) that the increase (7-fold) in the anteiso-15:0/anteiso-17:0 fatty acid ratio, FAr, for cold NL was at variance with the ratio for TL and PL (about 10-fold). We correlated our findings with DSC studies on phase transition temperature (Tc), enthalpy difference (DeltaH) and peak range of the transition for TL, PL, NL (from cultures at 30 and 5 degrees C); The decrease of Tc (10.5 degrees C) and DeltaH (51%) for TL is a reflection of the decrease of Tc (11.5 degrees C) and DeltaH (56%) for PL. This large decrease is interpreted by the high (10-fold) increase of a-15:0/a-17:0 FAr of PL5 degrees C. In NL the decrease of Tc (3 degrees C) and of DeltaH (42%) is interpreted by both adaptation mechanisms: the (lower) 7-fold increase of anteiso-15:0/anteiso-17:0 FAr and the NL percentage calculated from increased mass values. The peak range of TL5 degrees C (from -15 to 25 degrees C) is a reflection of the peak range of NL5 degrees C, which is unchanged, as is the peak range of NL30 degrees C.

Determination of phospholipids in dairy products by SPE/HPLC/ELSD

The aim of this work was to evaluate the performance of different methods for both milk lipid extraction and phospholipids separation. As far as the lipid extraction procedure is concerned, the Folch method showed a higher phospholipid recovery with respect to the Rose-Gottlieb method. Different SPE cartridges and solvent phases were tested to carry out the separation of phospholipids from fat. The yield of extraction was evaluated by isolating phospholipids from both milk fat and synthetic fat; Standard Addition Method was applied as well. The isolation of the phospholipids by SPE silica column and subsequent analysis by HPLC/ELSD was shown to be an accurate and reproducible analytical method for the determination of phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylcholine and sphingomyelin in milk fat extracted by Folch method.

Separation and quantitation of peroxidized phospholipids using high-performance thin-layer chromatography with tetramethyl-p-phenylenediamine detection

A simple method for the selective determination of phospholipid hydroperoxide (PLOOH) families in complex lipid populations has been developed. Referred to as HPTLC-TPD, the method is based on PLOOH separation by normal-phase high-performance thin-layer chromatography, followed by spray detection with N,N,N',N'-tetramethyl-p-phenylenediamine and densitometric scanning of the purple bands. Parental phospholipids and alcohol analogues are unreactive. Calibration curves, dynamic ranges, and detection limits were established for hydroperoxide standards prepared from phospatidylcholine, phosphatidylserine, phosphatidylethanolamine, and cardiolipin. For all PLOOH classes, responsiveness was linear out to at least 10 nmol of sample load, the detection limit being 0.1-0.2 nmol. HPTLC-TPD data were validated by subjecting duplicate samples to more complex column chromatography with reductive-mode electrochemical detection. General applicability of the new technique was demonstrated using lipid extracts from two test systems: (i) photoperoxidized liposomal membranes and (ii) tumor cells that had been oxidatively stressed with the respiratory inhibitor antimycin A. HPTLC-TPD provides a convenient, specific, and highly sensitive means for quantifying individual PLOOH families in complex natural mixtures.

Occurrence of high levels of tetracosahexaenoic acid in the jellyfish Aurelia sp

The FA composition of the pelagic jellyfish Aurelia sp. collected from off-shore Western Australia waters was determined by capillary GC and GC-MS, with confirmation of PUFA structure performed by analysis of 4,4-dimethyloxazoline derivatives. PUFA constituted 47.6% of the total FA, with the essential PUFA eicosapentaenoic acid (EPA), arachidonic acid, and DHA accounting for 34%. Of particular interest, the unusual very long chain PUFA 6,9,12,15,18,21-tetracosahexaenoic acid (THA, 24:6n-3) was present at 9.3%, and the rarely reported 6,9,12,15,18-tetracosapentaenoic acid (24:5n-6) also was detected at 0.8%. To our knowledge, this represents the first report of THA as a major PUFA in a pelagic marine organism.

Sphingophosphonolipid molecular species from edible mollusks and a jellyfish

The goal of this study is to supplement the composition and nature of sphingophosphonolipids diversity from edible mollusks (Mytilus galloprovincialis, Eobania vermiculata) and from jellyfish Pelagia noctiluca, organisms rich in phosphonolipids. M. galloprovincialis contained a major ceramide 2-aminoethylphosphonate (CAEP-IM) and a minor ceramide that was detected chromatographically as the methyl analog (CAEP-IIM). In CAEP-IM, saturated fatty acids (FA) of 14, 16 and 18 carbons amounted to 68.8%; also 52.5% dihydroxy bases were detected. On thin layer chromatography, the Rf for CAEP-IIM was smaller than the Rf for CAEP-IM because of an increase of 22.0% in 2OH-16:0 FA, plus 29.2% trihydroxy bases (phytosphingosine). Similarly, a ceramide 2-methylaminoethylphosphonate (CAEP-IIE, 1.5% of phospholipids) was quantitated in Eobania (apart from the previously reported major CAEP, 7.6%). In CAEP-IIE, saturated and hydroxy FA of 14, 16 and 18 carbons amounted to 37.0 and 37.8%; 29.1% dihydroxy and 23.0% trihydroxy bases were detected in the same molecule. Eobania's unsaturated FA percentages (total lipids: 66.3, polar: 47.5, neutral: 59.0) were similar to those previously found for other land snails. A suite of two minor CAEP (CAEP-IIP, CAEP-IIIP) was quantitated in Pelagia at 2.0 and 1.3% of phospholipids (apart from the previously reported major CAEP, 21.0%) identified chromatographically as methyl analogs. In CAEP-IIP, saturated FA of 14, 16, 18 and 19 carbons amounted to 56.0%; 12.6% dihydroxy and 34.1% trihydroxy bases were also detected in CAEP-IIP. The Rf CAEP-IIIP<Rf CAEP-IIP owing to an increase of +8.5% of hydroxy FA and +12.3% of trihydroxy bases. The compositions of CAEP-IIM and CAEP-IIE appear to be specific of each organism, while the composition of molluscan or jellyfish major sphingophosphonolipids appears not specific.

The 2-aminoethylphosphonate-specific transaminase of the 2-aminoethylphosphonate degradation pathway

The 2-aminoethylphosphonate transaminase (AEPT; the phnW gene product) of the Salmonella enterica serovar Typhimurium 2-aminoethylphosphonate (AEP) degradation pathway catalyzes the reversible reaction of AEP and pyruvate to form phosphonoacetaldehyde (P-Ald) and L-alanine (L-Ala). Here, we describe the purification and characterization of recombinant AEPT. pH rate profiles (log V(m) and log V(m)/K(m) versus pH) revealed a pH optimum of 8.5. At pH 8.5, K(eq) is equal to 0.5 and the k(cat) values of the forward and reverse reactions are 7 and 9 s(-1), respectively. The K(m) for AEP is 1.11 +/- 0.03 mM; for pyruvate it is 0.15 +/- 0.02 mM, for P-Ald it is 0.09 +/- 0.01 mM, and for L-Ala it is 1.4 +/- 0.03 mM. Substrate specificity tests revealed a high degree of discrimination, indicating a singular physiological role for the transaminase in AEP degradation. The 40-kDa subunit of the homodimeric enzyme is homologous to other members of the pyridoxalphosphate-dependent amino acid transaminase superfamily. Catalytic residues conserved within well-characterized members are also conserved within the seven known AEPT sequences. Site-directed mutagenesis demonstrated the importance of three selected residues (Asp168, Lys194, and Arg340) in AEPT catalysis.