Heliothis virescens chymotrypsin is translationally controlled by AeaTMOF binding ABC putative receptor.

Heliothis virescens larval chymotrypsin (GenBank accession number AF43709) was cloned, sequenced and its three dimensional (3D) conformation modeled. The enzyme's transcript was first detected 6 days after larval emergence and the transcript level was shown to fall between larval ecdysis periods. Comparisons between the activities of larval gut chymotrypsin and trypsin shows that chymotrypsin activity is only 16% of the total trypsin activity and the pH optimum of the larval chymotrypsin is between pH 9-10, however the enzyme also exhibited a broad activity between pH 4-6. Injections of AeaTMOF and several shorter analogues into 3rd instar larvae followed by Northern blot analyses showed that although the chymotrypsins activities were inhibited by 60%-80% the transcript level of the sequenced chymotrypsin was not reduced and was similar to controls in which the chymotrypsin activity was not inhibited, indicating that AeaTMOF and its analogues exert a translational control. Based on these observations a putative AeaTMOF receptor (ABCC4) homologous to the Ae. aegypti ABC receptor sequence was found in the H. virescens genome. 3D molecular modeling and docking of the AeaTMOF and several of its analogues to the ABCC4 receptor showed that it can bind AeaTMOF and its analogues as was shown before for the Ae. aegypti receptor.

Modeling and hexahedral meshing of cerebral arterial networks from centerlines.

Computational fluid dynamics (CFD) simulation provides valuable information on blood flow from the vascular geometry. However, it requires extracting precise models of arteries from low-resolution medical images, which remains challenging. Centerline-based representation is widely used to model large vascular networks with small vessels, as it encodes both the geometric and topological information and facilitates manual editing. In this work, we propose an automatic method to generate a structured hexahedral mesh suitable for CFD directly from centerlines. We addressed both the modeling and meshing tasks. We proposed a vessel model based on penalized splines to overcome the limitations inherent to the centerline representation, such as noise and sparsity. The bifurcations are reconstructed using a parametric model based on the anatomy that we extended to planar n-furcations. Finally, we developed a method to produce a volume mesh with structured, hexahedral, and flow-oriented cells from the proposed vascular network model. The proposed method offers better robustness to the common defects of centerlines and increases the mesh quality compared to state-of-the-art methods. As it relies on centerlines alone, it can be applied to edit the vascular model effortlessly to study the impact of vascular geometry and topology on hemodynamics. We demonstrate the efficiency of our method by entirely meshing a dataset of 60 cerebral vascular networks. 92% of the vessels and 83% of the bifurcations were meshed without defects needing manual intervention, despite the challenging aspect of the input data. The source code is released publicly.

Cloning and characterization of Aedes aegypti blood downregulated chymotrypsin II.

Aedes aegypti adult and larval blood downregulated chymotrypsin II was cloned, sequenced and its 3D conformation modeled. Cloning of the enzymes from adult and larval guts indicated that both genes sit at the same location on Chromosome 2. Genomic analyses showed that larval and adult genes are the same and both have four exons and three introns that are located on an 8.32 Kb DNA in direction with the Ae. aegypti genome. The adult and larval transcript synthesis is controlled by alternative splicing explaining small difference in the amino acids sequences. Chymotrypsin II that was extracted from guts of sugar-fed and at 48 after blood feeding showed a pH optimum of 4-5 with a broad shoulder of activity from pH 6 to 10. Dot blot analyses show that the enzyme's transcript is downregulated after females take a blood meal and upregulated at 48 h after the blood meal. A Chymotrypsin II transcript was also detected in the larval gut during different times of larval developmental stages, indication that Ae. aegypti chymotrypsin II is synthesized by adults and larval guts. The possibility that JH III and 20HE play an active role in the regulation is discussed.

Plant lectins as versatile tools to fight coronavirus outbreaks.

The S protein forming the homotrimeric spikes of pathogenic beta-coronaviruses, such as MERS-CoV, SARS-CoV and SARS-CoV-2, is a highly glycosylated protein containing mainly N-glycans of the complex and high-mannose type, as well as O-glycans. Similarly, the host cell receptors DPP4 for MERS-CoV and ACE2 for SARS-CoV and SARS-CoV-2, also represent N- and O-glycosylated proteins. All these glycoproteins share common glycosylation patterns, suggesting that plant lectins with different carbohydrate-binding specificities could be used as carbohydrate-binding agents for the spikes and their receptors, to combat COVID19 pandemics. The binding of plant lectins to the spikes and their receptors could mask the non-glycosylated receptor binding domain of the virus and the corresponding region of the receptor, thus preventing a proper interaction of the spike proteins with their receptors. In this review, we analyze (1) the ability of plant lectins to interact with the N- and O-glycans present on the spike proteins and their receptors, (2) the in vitro and in vivo anti-COVID19 activity already reported for plant lectins and, (3) the possible ways for delivery of lectins to block the spikes and/or their receptors.

Cloning and characterization of Aedes aegypti juvenile hormone epoxide hydrolases (JHEHs).

Juvenile hormone epoxide hydrolase (JHEH) plays an important role in the metabolism of juvenile hormone III (JH III) in insects. To study the role that JHEH plays in female Aedes aegypti JHEH 1, 2, and 3 complementary DNA (cDNAs) were cloned and sequenced. Northern blot analyses show that the three transcripts are expressed in the head thorax, the gut, the ovaries, and the fat body of females. Molecular modeling shows that the enzyme is a homodimer that binds JH III acid (JH IIIA) at the catalytic groove better than JH III. The cDNA of JHEH 1 and 2 are very similar indicating close relationship. Knocking down of jheh 1, 2, and 3 in adult female and larval Ae. aegypti using double-stranded RNA (dsRNA) did not affect egg development or caused adult mortality. Larvae that were fed bacterial cells expressing dsRNA against jheh 1, 2, and 3 grew normally. Treating blood-fed female Ae. aegypti with [12-3 H](10R) JH III and analyzing the metabolites by C18 reversed phase chromatography showed that JHEH preferred substrate is not JH III but JH IIIA. Genomic analysis of jheh 1, 2, and 3 indicate that jheh 1 and 2 are transcribed from a 1.53 kb DNA whereas jheh 3 is transcribed from a 10.9 kb DNA. All three genes are found on chromosome two at distinct locations. JHEH 2 was expressed in bacterial cells and purified by Ni affinity chromatography. Sequencing of the recombinant protein by MS/MS identified JHEH 2 as the expressed recombinant protein.

Cloning and Characterization of Drosophila melanogaster Juvenile Hormone Epoxide Hydrolases (JHEH) and Their Promoters.

Juvenile hormone epoxide hydrolase (JHEH) plays an important role in the metabolism of JH III in insects. To study the control of JHEH in female Drosophila melanogaster, JHEH 1, 2 and 3 cDNAs were cloned and sequenced. Northern blot analyses showed that the three transcripts are expressed in the head thorax, the gut, the ovaries and the fat body of females. Molecular modeling shows that the enzyme is a homodimer that binds juvenile hormone III acid (JH IIIA) at the catalytic groove better than JH III. Analyses of the three JHEH promoters and expressing short promoter sequences behind a reporter gene (lacZ) in D. melanogaster cell culture identified a JHEH 3 promoter sequence (626 bp) that is 10- and 25-fold more active than the most active promoter sequences of JHEH 2 and JHEH 1, respectively. A transcription factor (TF) Sp1 that is involved in the activation of JHEH 3 promoter sequence was identified. Knocking down Sp1 using dsRNA inhibited the transcriptional activity of this promoter in transfected D. melanogaster cells and JH III and 20HE downregulated the JHEH 3 promoter. On the other hand, JH IIIA and farnesoic acid did not affect the promoter, indicating that JH IIIA is JHEH's preferred substrate. A transgenic D. melanogaster expressing a highly activated JHEH 3 promoter behind a lacZ reporter gene showed promoter transcriptional activity in many D. melanogaster tissues.

The Ribosome Is the Ultimate Receptor for Trypsin Modulating Oostatic Factor (TMOF).

Aedes aegypti Trypsin Modulating Oostatic Factor (AeaTMOF). a mosquito decapeptide that controls trypsin biosynthesis in female and larval mosquitoes. enters the gut epithelial cells of female mosquitoes using ABC-tmfA receptor/importer. To study the ultimate targeted receptor after AeaTMOF enters the cell, AeaTMOF was incubated in vitro with either Escherichia coli or Spodoptera frugiperda protein-expressing extracts containing 70S and 80S ribosomes, respectively. The effect of AeaTMOF on luciferase biosynthesis in vitro using 70S ribosomes was compared with that of oncocin112 (1-13), a ribosome-binding antibacterial peptide. The IC50 of 1 µM and 2 µM, respectively, for both peptides was determined. Incubation with a protein-expressing system and S. frugiperda 80S ribosomes determined an IC50 of 1.8 µM for Aedes aegypti larval late trypsin biosynthesis. Incubation of purified E. coli ribosome with increasing concentration of AeaTMOF shows that the binding of AeaTMOF to the bacterial ribosome exhibits a high affinity (KD = 23 ± 3.4 nM, Bmax = 0.553 ± 0.023 pmol/µg ribosome and Kassoc = 4.3 × 107 M-1). Molecular modeling and docking experiments show that AeaTMOF binds bacterial and Drosophila ribosome (50S and 60S, respectively) at the entrance of the ribosome exit tunnel, blocking the tRNA entrance and preventing protein biosynthesis. Recombinant E. coli cells that express only ABC-tmfA importer are inhibited by AeaTMOF but not by oncocin112 (1-13). These results suggest that the ribosome is the ultimate targeted receptor of AeaTMOF.

How Do Point Mutations Enhancing the Basic Character of the RBDs of SARS-CoV-2 Variants Affect Their Transmissibility and Infectivity Capacities?

The spread of SARS-CoV-2 variants in the population depends on their ability to anchor the ACE2 receptor in the host cells. Differences in the electrostatic potentials of the spike protein RBD (electropositive/basic) and ACE2 receptor (electronegative/acidic) play a key role in both the rapprochement and the recognition of the coronavirus by the cell receptors. Accordingly, point mutations that result in an increase in electropositively charged residues, e.g., arginine and lysine, especially in the RBD of spike proteins in the SARS-CoV-2 variants, could contribute to their spreading capacity by favoring their recognition by the electronegatively charged ACE2 receptors. All SARS-CoV-2 variants that have been recognized as being highly transmissible, such as the kappa (κ), delta (δ) and omicron (o) variants, which display an enhanced electropositive character in their RBDs associated with a higher number of lysine- or arginine-generating point mutations. Lysine and arginine residues also participate in the enhanced RBD-ACE2 binding affinity of the omicron variant, by creating additional salt bridges with aspartic and glutamic acid residues from ACE2. However, the effects of lysine- and arginine-generating point mutations on infectivity is more contrasted, since the overall binding affinity of omicron RBD for ACE2 apparently results from some epistasis among the whole set of point mutations.

Legume Lectins with Different Specificities as Potential Glycan Probes for Pathogenic Enveloped Viruses.

Pathogenic enveloped viruses are covered with a glycan shield that provides a dual function: the glycan structures contribute to virus protection as well as host cell recognition. The three classical types of N-glycans, in particular complex glycans, high-mannose glycans, and hybrid glycans, together with some O-glycans, participate in the glycan shield of the Ebola virus, influenza virus, human cytomegalovirus, herpes virus, human immunodeficiency virus, Lassa virus, and MERS-CoV, SARS-CoV, and SARS-CoV-2, which are responsible for respiratory syndromes. The glycans are linked to glycoproteins that occur as metastable prefusion glycoproteins on the surface of infectious virions such as gp120 of HIV, hemagglutinin of influenza, or spike proteins of beta-coronaviruses. Plant lectins with different carbohydrate-binding specificities and, especially, mannose-specific lectins from the Vicieae tribe, such as pea lectin and lentil lectin, can be used as glycan probes for targeting the glycan shield because of their specific interaction with the α1,6-fucosylated core Man3GlcNAc2, which predominantly occurs in complex and hybrid glycans. Other plant lectins with Neu5Ac specificity or GalNAc/T/Tn specificity can also serve as potential glycan probes for the often sialylated complex glycans and truncated O-glycans, respectively, which are abundantly distributed in the glycan shield of enveloped viruses. The biomedical and therapeutical potential of plant lectins as antiviral drugs is discussed.

Bactericidal Properties of Proline-Rich Aedes aegypti Trypsin Modulating Oostatic Factor (AeaTMOF).

The antimicrobial properties of proline-rich Aedes aegypti decapeptide TMOF (AeaTMOF) and oncocin112 (1-13) were compared. Incubations with multidrug-resistant Escherichia coli cells showed that AeaTMOF (5 mM) was able to completely inhibit bacterial cell growth, whereas oncocin112 (1-13) (20 mM) partially inhibited bacterial growth as compared with bacterial cells that were not multidrug-resistant cells. AeaTMOF (5 mM) was very effective against Acinetobacter baumannii and Pseudomonas aeruginosa, completely inhibiting cell growth during 15 h incubations. AeaTMOF (5 mM) completely inhibited the Gram-positive bacteria Staphylococcus aureus and Bacillus thurengiensis sups. Israelensis cell growth, whereas oncocin112 (1-13) (10 and 20 mM) failed to affect bacterial cell growth. E. coli cells that lack the SbmA transporter were inhibited by AeaTMOF (5 mM) and not by oncocin112 (1-13) (10 to 20 mM), indicating that AeaTMOF can use other bacterial transporters than SbmA that is mainly used by proline-rich antimicrobial peptides. Incubation of E. coli cells with NaAzide showed that AeaTMOF does not use ABC-like transporters that use ATP hydrolysis to import molecules into bacterial cells. Three-dimensional modeling and docking of AeaTMOF to SbmA and MdtM transporters showed that AeaTMOF can bind these proteins, and the binding location of AeaTMOF inside these protein transporters allows AeaTMOF to be transported into the bacterial cytosol. These results show that AeaTMOF can be used as a future antibacterial agent against both multidrug-resistant Gram-positive and -negative bacteria.

Culex quinquefasciatus Late Trypsin Biosynthesis Is Translationally Regulated by Trypsin Modulating Oostatic Factor.

Trypsin is a serine protease that is synthesized by the gut epithelial cells of female mosquitoes; it is the enzyme that digests the blood meal. To study its molecular regulation, Culex quinquefasciatus late trypsin was purified by diethylaminoethyl (DEAE), affinity, and C18 reverse-phase high performance liquid chromatography (HPLC) steps, and the N-terminal amino acid sequence was determined for molecular cloning. Five overlapping segments of the late trypsin cDNA were amplified by PCR, cloned, and the full sequence (855 bp) was characterized. Three-dimensional models of the pro-trypsin and activated trypsin were built and compared with other trypsin models. Trypsin modulating oostatic factor (TMOF) concentrations in the hemolymph were determined by ELISA and compared with trypsin activity in the gut after the blood meal. The results showed that there was an increase in TMOF concentrations circulating in the hemolymph which has correlated to the reduction of trypsin activity in the mosquito gut. Northern blot analysis of the trypsin transcripts after the blood meal indicated that trypsin activity also followed the increase and decrease of the trypsin transcript. Injections of different amounts of TMOF (0.025 to 50 µg) decreased the amounts of trypsin in the gut. However, Northern blot analysis showed that TMOF injections did not cause a decrease in trypsin transcript abundance, indicating that TMOF probably affected trypsin translation.

The T/Tn-Specific Helix pomatia Lectin Induces Cell Death in Lymphoma Cells Negative for T/Tn Antigens.

Morniga G is a T/Tn-specific lectin, inducing cell death in Tn-positive leukemias but not in healthy lymphocytes. Helix pomatia lectin (HPA) is another T/Tn-specific lectin, currently used as tool for cancer diagnostics. The HPA-mediated tumor cell death was evaluated on human leukemia and mouse lymphoma cells, and compared to the effect of Morniga G. Both lectins induced an equivalent percentage of cell death in Tn-positive Jurkat human leukemia. In contrast, EL4 mouse lymphoma resisted Morniga G-mediated cytotoxicity but were killed by HPA at concentrations of 2.5 µg/mL (0.032 nM) and higher. In both malignant cells, HPA-mediated cell death showed features compatible with apoptosis (annexin-externalization, caspase-activation, mitochondrial membrane depolarization, and ROS production). Cytometry analysis indicated that EL4 cells are T/Tn-negative. Because previous results showed a high amount of N-acetylgalactosamine (GalNAc, sugar present in Tn antigen) on EL4 cell surface, this GalNAc could be involved in the formation of truncated O-glycans other than the T/Tn residues. When compared to Morniga G, bioinformatic analysis suggested that HPA benefits from an extended carbohydrate-binding site, better adapted than Morniga G to the accommodation of more complex branched and truncated O-glycans (such as core 2). Finally, HPA killed EL4 cells but not healthy lymphocytes in a mixture of lymphoma cells + lymphocytes, suggesting that HPA selectively triggers tumor cell death.

Cloning and Characterization of Aedes aegypti Trypsin Modulating Oostatic Factor (TMOF) Gut Receptor.

Trypsin Modulating Oostatic Factor (TMOF) receptor was solubilized from the guts of female Ae. Aegypti and cross linked to His6-TMOF and purified by Ni affinity chromatography. SDS PAGE identified two protein bands (45 and 61 kDa). The bands were cut digested and analyzed using MS/MS identifying a protein sequence (1306 amino acids) in the genome of Ae. aegypti. The mRNA of the receptor was extracted, the cDNA sequenced and cloned into pTAC-MAT-2. E. coli SbmA- was transformed with the recombinant plasmid and the receptor was expressed in the inner membrane of the bacterial cell. The binding kinetics of TMOF-FITC was then followed showing that the cloned receptor exhibits high affinity to TMOF (KD = 113.7 ± 18 nM ± SEM and Bmax = 28.7 ± 1.8 pmol ± SEM). Incubation of TMOF-FITC with E. coli cells that express the receptor show that the receptor binds TMOF and imports it into the bacterial cells, indicating that in mosquitoes the receptor imports TMOF into the gut epithelial cells. A 3D modeling of the receptor indicates that the receptor has ATP binding sites and TMOF transport into recombinant E. coli cells is inhibited with ATPase inhibitors Na Arsenate and Na Azide.

Man-Specific Lectins from Plants, Fungi, Algae and Cyanobacteria, as Potential Blockers for SARS-CoV, MERS-CoV and SARS-CoV-2 (COVID-19) Coronaviruses: Biomedical Perspectives.

Betacoronaviruses, responsible for the "Severe Acute Respiratory Syndrome" (SARS) and the "Middle East Respiratory Syndrome" (MERS), use the spikes protruding from the virion envelope to attach and subsequently infect the host cells. The coronavirus spike (S) proteins contain receptor binding domains (RBD), allowing the specific recognition of either the dipeptidyl peptidase CD23 (MERS-CoV) or the angiotensin-converting enzyme ACE2 (SARS-Cov, SARS-CoV-2) host cell receptors. The heavily glycosylated S protein includes both complex and high-mannose type N-glycans that are well exposed at the surface of the spikes. A detailed analysis of the carbohydrate-binding specificity of mannose-binding lectins from plants, algae, fungi, and bacteria, revealed that, depending on their origin, they preferentially recognize either complex type N-glycans, or high-mannose type N-glycans. Since both complex and high-mannose glycans substantially decorate the S proteins, mannose-specific lectins are potentially useful glycan probes for targeting the SARS-CoV, MERS-CoV, and SARS-CoV-2 virions. Mannose-binding legume lectins, like pea lectin, and monocot mannose-binding lectins, like snowdrop lectin or the algal lectin griffithsin, which specifically recognize complex N-glycans and high-mannose glycans, respectively, are particularly adapted for targeting coronaviruses. The biomedical prospects of targeting coronaviruses with mannose-specific lectins are wide-ranging including detection, immobilization, prevention, and control of coronavirus infection.

A Proteomic- and Bioinformatic-Based Identification of Specific Allergens from Edible Insects: Probes for Future Detection as Food Ingredients.

The increasing development of edible insect flours as alternative sources of proteins added to food and feed products for improving their nutritional value, necessitates an accurate evaluation of their possible adverse side-effects, especially for individuals suffering from food allergies. Using a proteomic- and bioinformatic-based approach, the diversity of proteins occurring in currently consumed edible insects such as silkworm (Bombyx mori), cricket (Acheta domesticus), African migratory locust (Locusta migratoria), yellow mealworm (Tenebrio molitor), red palm weevil (Rhynchophorus ferrugineus), and giant milworm beetle (Zophobas atratus), was investigated. Most of them consist of phylogenetically-related protein allergens widely distributed in the different groups of arthropods (mites, insects, crustaceans) and mollusks. However, a few proteins belonging to discrete protein families including the chemosensory protein, hexamerin, and the odorant-binding protein, emerged as proteins highly specific for edible insects. To a lesser extent, other proteins such as apolipophorin III, the larval cuticle protein, and the receptor for activated protein kinase, also exhibited a rather good specificity for edible insects. These proteins, that are apparently missing or much less represented in other groups of arthropods, mollusks and nematods, share well conserved amino acid sequences and very similar three-dimensional structures. Owing to their ability to trigger allergic responses in sensitized people, they should be used as probes for the specific detection of insect proteins as food ingredients in various food products and thus, to assess their food safety, especially for people allergic to edible insects.

Are Dietary Lectins Relevant Allergens in Plant Food Allergy?

Lectins or carbohydrate-binding proteins are widely distributed in seeds and vegetative parts of edible plant species. A few lectins from different fruits and vegetables have been identified as potential food allergens, including wheat agglutinin, hevein (Hev b 6.02) from the rubber tree and chitinases containing a hevein domain from different fruits and vegetables. However, other well-known lectins from legumes have been demonstrated to behave as potential food allergens taking into account their ability to specifically bind IgE from allergic patients, trigger the degranulation of sensitized basophils, and to elicit interleukin secretion in sensitized people. These allergens include members from the different families of higher plant lectins, including legume lectins, type II ribosome-inactivating proteins (RIP-II), wheat germ agglutinin (WGA), jacalin-related lectins, GNA (Galanthus nivalis agglutinin)-like lectins, and Nictaba-related lectins. Most of these potentially active lectin allergens belong to the group of seed storage proteins (legume lectins), pathogenesis-related protein family PR-3 comprising hevein and class I, II, IV, V, VI, and VII chitinases containing a hevein domain, and type II ribosome-inactivating proteins containing a ricin B-chain domain (RIP-II). In the present review, we present an exhaustive survey of both the structural organization and structural features responsible for the allergenic potency of lectins, with special reference to lectins from dietary plant species/tissues consumed in Western countries.

Man-Specific, GalNAc/T/Tn-Specific and Neu5Ac-Specific Seaweed Lectins as Glycan Probes for the SARS-CoV-2 (COVID-19) Coronavirus.

Seaweed lectins, especially high-mannose-specific lectins from red algae, have been identified as potential antiviral agents that are capable of blocking the replication of various enveloped viruses like influenza virus, herpes virus, and HIV-1 in vitro. Their antiviral activity depends on the recognition of glycoprotein receptors on the surface of sensitive host cells-in particular, hemagglutinin for influenza virus or gp120 for HIV-1, which in turn triggers fusion events, allowing the entry of the viral genome into the cells and its subsequent replication. The diversity of glycans present on the S-glycoproteins forming the spikes covering the SARS-CoV-2 envelope, essentially complex type N-glycans and high-mannose type N-glycans, suggests that high-mannose-specific seaweed lectins are particularly well adapted as glycan probes for coronaviruses. This review presents a detailed study of the carbohydrate-binding specificity of high-mannose-specific seaweed lectins, demonstrating their potential to be used as specific glycan probes for coronaviruses, as well as the biomedical interest for both the detection and immobilization of SARS-CoV-2 to avoid shedding of the virus into the environment. The use of these seaweed lectins as replication blockers for SARS-CoV-2 is also discussed.

Insights into the Allergenic Potential of the Edible Yellow Mealworm (Tenebrio molitor).

The edible yellow mealworm (Tenebrio molitor), contains an extremely diverse panel of soluble proteins, including proteins with structural functions such as muscle proteins, as well as proteins involved in metabolic functions such as enzymes. Most of these proteins display a more or less pronounced allergenic character toward previously sensitized people, especially people allergic to shrimps and other shellfish. A mass spectrometry approach following the separation of a mealworm protein, extracted by sodiumdodecyl sulfate-polyacrylamide gel electrophoresis, allowed us to identify up to 106 distinct protein fractions including molecules with structural and functional functions, susceptible to developing an allergenic potential due to the possibility of immunoglobulin E-binding cross-reactions with their counterparts occurring in shellfish. In this respect, most of the sera from people allergic to shrimps reacted with the mealworm protein extract in Western blot experiments. Moreover, the potential mealworm allergens triggered the in vitro degranulation of rat leukemic basophils transfected with the human high-affinity IgE receptor (FcεRI), upon sensitization by the IgE-containing sera from people allergic to shrimps and other shellfish foods. Owing to the large repertoire of IgE-binding cross-reacting allergens the yellow mealworm shares with other phylogenetically-related groups of arthropods, it would seem prudent to inform the consumers, especially those allergic to shellfish, by appropriate labeling on edible mealworm packages about the potential risk of developing an allergic reaction.

Mannose-Specific Lectins from Marine Algae: Diverse Structural Scaffolds Associated to Common Virucidal and Anti-Cancer Properties.

To date, a number of mannose-specific lectins have been isolated and characterized from seaweeds, especially from red algae. In fact, man-specific seaweed lectins consist of different structural scaffolds harboring a single or a few carbohydrate-binding sites which specifically recognize mannose-containing glycans. Depending on the structural scaffold, man-specific seaweed lectins belong to five distinct structurally-related lectin families, namely (1) the griffithsin lectin family (ß-prism I scaffold); (2) the Oscillatoria agardhii agglutinin homolog (OAAH) lectin family (ß-barrel scaffold); (3) the legume lectin-like lectin family (ß-sandwich scaffold); (4) the Galanthus nivalis agglutinin (GNA)-like lectin family (ß-prism II scaffold); and, (5) the MFP2-like lectin family (MFP2-like scaffold). Another algal lectin from Ulva pertusa, has been inferred to the methanol dehydrogenase related lectin family, because it displays a rather different GlcNAc-specificity. In spite of these structural discrepancies, all members from the five lectin families share a common ability to specifically recognize man-containing glycans and, especially, high-mannose type glycans. Because of their mannose-binding specificity, these lectins have been used as valuable tools for deciphering and characterizing the complex mannose-containing glycans from the glycocalyx covering both normal and transformed cells, and as diagnostic tools and therapeutic drugs that specifically recognize the altered high-mannose N-glycans occurring at the surface of various cancer cells. In addition to these anti-cancer properties, man-specific seaweed lectins have been widely used as potent human immunodeficiency virus (HIV-1)-inactivating proteins, due to their capacity to specifically interact with the envelope glycoprotein gp120 and prevent the virion infectivity of HIV-1 towards the host CD4+ T-lymphocyte cells in vitro.