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Rômulo Farias Carneiro - One of the best experts on this subject based on the ideXlab platform.
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New lectins from Codium isthmocladum Vickers show unique amino acid sequence and antibiofilm effect on pathogenic bacteria
Journal of Applied Phycology, 2020Co-Authors: Rômulo Farias Carneiro, Renata Pinheiro Chaves, Mayron Alves De Vasconcelos, Philippe Lima Duarte, Suzete Roberta Silva, Ramon Rodrigues Feitosa, Bruno Lopes Sousa, Antônio Willame Alves, Bruno Anderson Matias Rocha, Edson Holanda TeixeiraAbstract:Two new lectins from the green alga Codium isthmocladum (CiL-1 and CiL-2) were isolated. Both lectins could agglutinate human and rabbit erythrocytes. Galactosides and fetuin showed inhibitory effect on CiL-1. CiL-2 was inhibited by GalNAc and porcine Stomach Mucin. CiL-1 was a monomeric protein of 12 kDa, whereas CiL-2 showed 12 kDa in SDS-PAGE and an oligomeric state in gel filtration. MALDI-ToF-MS of CiL-1 revealed a molecular mass of 12.027 ± 5 Da, while CiL-2 showed molecular mass of 12.264 ± 5 Da. Ninety-eight percent of CiL-1’s primary structure was determined consisting of 112 residues placed in two repeated domains with approximately 60% of similarity. CiL-1 showed similarity with hypothetical proteins from aquatic pathogenic fungi. The N-terminal of CiL-2 showed no similarity to CiL-1 or to any known protein. The three-dimensional model of CiL-1 consists of four two-strand β-sheets disposed in a barrel-like arrangement, connected by loops of variable sizes, with a well-structured hydrophobic core. Binding site prediction suggests the existence of two independent monosaccharide binding sites in CiL-1. The lectins showed no antibacterial activity on Gram-positive and Gram-negative bacteria, but they were able to significantly inhibit the biofilm formation from Staphylococcus aureus and Staphylococcus epidermidis.
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Isolation, biochemical characterization and antibiofilm effect of a lectin from the marine sponge Aplysina lactuca
International journal of biological macromolecules, 2017Co-Authors: Rômulo Farias Carneiro, Celso Shiniti Nagano, Renata Pinheiro Chaves, Mayron Alves De Vasconcelos, Paulo Henrique Pinheiro De Lima, Rafael Pereira, Anna Luísa Pereira, Ulisses Pinheiro, Edson Holanda Teixeira, Alexandre Holanda SampaioAbstract:A new lectin was isolated from the marine sponge Aplysina lactuca (ALL) by combining ammonium sulfate precipitation and affinity chromatography on guar gum matrix. ALL showed affinity for the disaccharides α-lactose, β-lactose and lactulose (Ka=12.5, 31.9 and 145.5M-1, respectively), as well as the glycoprotein porcine Stomach Mucin. Its hemagglutinating activity was stable in neutral acid pH values and temperatures below 60°C. ALL is a dimeric protein formed by two covalently linked polypeptide chains. The average molecular mass, as determined by Electrospray Ionization Mass Spectrometry (ESI-MS), was 31,810±2Da. ESI-MS data also indicated the presence of three cysteines involved in one intrachain and one interchain disulfide bond. The partial amino acid sequence of ALL was determined by tandem mass spectrometry. Eight tryptic peptides presented similarity with lectin I isolated from Axinella polypoides. Its secondary structure is predominantly β-sheet, as indicated by circular dichroism (CD) spectroscopy. ALL agglutinated gram-positive and gram-negative bacterial cells, and it were able to significantly reduce the biomass of the bacterial biofilm tested at dose- dependent effect.
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HGA-2, a novel galactoside-binding lectin from the sea cucumber Holothuria grisea binds to bacterial cells
International journal of biological macromolecules, 2014Co-Authors: Arthur Alves De Melo, Silvana Saker-sampaio, Kyria S. Nascimento, Rômulo Farias Carneiro, Winnie De Melo Silva, Raniere Da Mata Moura, Giselle Cristina Silva, Oscarina Viana De Sousa, Jefferson Pablo De Sousa Saboya, Celso Shiniti NaganoAbstract:Abstract A novel lectin, HGA-2, was isolated from the sea cucumber Holothuria grisea . The protein was isolated by a single chromatographic step using a column of Guar Gum as affinity. HGA-2 showed an apparent molecular mass of 17 kDa and 34 kDa under reducing and nonreducing conditions, respectively. The hemagglutinating activity was specific for rabbit erythrocytes, showing no activity for human blood A, B and O. Its hemagglutinating activity was inhibited by carbohydrates containing galactose, with higher affinity for GalNAc and glycoprotein porcine Stomach Mucin (PSM). HGA-2 was stable at pH 6–10, significantly declining at pH 5 and a temperature of 40 °C, with its activity being abolished at 100 °C. The HGA-2 protein was found to be Ca 2+ -dependent; it was highly toxic against Artemia nauplii and able to recognize and agglutinate cells of Escherichia coli . Amino acid sequences of tryptic peptides of HGA-2 strongly suggest that HGA-2 is a member of the C-type lectin family.
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h 3 a new lectin from the marine sponge haliclona caerulea purification and mass spectrometric characterization
The International Journal of Biochemistry & Cell Biology, 2013Co-Authors: Rômulo Farias Carneiro, Kyria S. Nascimento, Arthur Alves De Melo, Raniere Da Mata Moura, Alexandra Sampaio De Almeida, Renata Pinheiro Chaves, Bruno L Sousa, Silvana Saker Sampaio, Joao Paulo Matos Santos Lima, Benildo Sousa CavadaAbstract:Abstract A new lectin from the marine sponge Haliclona caerulea (H-3) was isolated using a combination of hydrophobic interaction chromatography and ion-exchange chromatography. H-3 is a protein with three distinct bands on SDS-PAGE: 9 kDa, 16 kDa and 18 kDa. Nevertheless, on gel filtration and N-PAGE, H-3 showed a symmetrical peak and a unique band, respectively. Hemagglutinating activity of H-3 was stable at neutral pH and temperatures up to 60 °C. N -Acetylgalactosamine and porcine Stomach Mucin were the most potent inhibitors of H-3. Primary structure of the lectin was determined using tandem mass spectrometry, and it showed no similarity to any members of the animal lectin families. Top down fragmentation revealed some posttranslational modifications in H-3, including glycosylation. The glycan composition of H-3 was determined, and its structure was predicted. Furthermore, H-3 is a blue protein, binding to a chromophore(-597) by weak interactions, and this is the first time that the interaction between one lectin and a natural chromophore has been shown.
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halilectin 1 h 1 and halilectin 2 h 2 two new lectins isolated from the marine sponge haliclona caerulea
Journal of Molecular Recognition, 2013Co-Authors: Rômulo Farias Carneiro, Kyria S. Nascimento, Arthur Alves De Melo, Raniere Da Mata Moura, Fernando Edson Pessoa Do Nascimento, Clareane Avelino Simplicio, B A M Rocha, Silvana Sakersampaio, Sula Salani Mota, Benildo Sousa CavadaAbstract:Two new lectins named Halilectin 1 (H-1) and Halilectin 2 (H-2) were isolated from the marine sponge Haliclona caerulea using a combination of affinity chromatography on stroma fixed onto Sephadex G-25 and cation and anion exchange chromatography. H-1 is a monomeric protein with a molecular mass of 40 kDa estimated using sodium dodecyl sulfate polyacrylamide gel electrophoresis and 15 kDa estimated using a TSK gel. Conversely, H-2 is a homodimeric protein with 15 kDa monomers linked via weak interactions. H-1 more effectively agglutinates trypsinized rabbit erythrocytes, whereas H-2 more effectively agglutinates native rabbit erythrocytes. The hemagglutinating activity of H-1 could be not inhibited by any tested sugars, but H-2 was inhibited by orosomucoid and porcine Stomach Mucin. Neither lectin was dependent on divalent ions. H-1 was stable at basic pH range and temperatures up to 50 °C, whereas H-2 was stable at acid pH range and temperatures up to 80 °C. The H. caerulea lectins exhibited dose-dependent toxicity against Artemia nauplii. Additionally, 76% of the primary structure of H-2 was determined using tandem mass spectrometry to contain a unique amino acid sequence with no similarity to any members of the animal lectin family. Copyright © 2012 John Wiley & Sons, Ltd.
Benildo Sousa Cavada - One of the best experts on this subject based on the ideXlab platform.
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A Diocleinae type II lectin from Dioclea lasiophylla Mart. Ex Benth seeds specific to α-lactose/GalNAc
Process Biochemistry, 2020Co-Authors: Benildo Sousa Cavada, Celso Shiniti Nagano, Vanir Reis Pinto-junior, Vinicius Jose Silva Osterne, Claudia Figueiredo Lossio, Mayara Torquato Lima Silva, Jorge Luis Almeida Correia, Sarah Elizabeth Gomes Correia, Messias Vital Oliveira, Lara Dias LimaAbstract:Abstract A type II lectin, designated as DlyL2, was purified from Dioclea lasiophylla Mart. ex Benth seeds and some of its physicochemical properties determined. The lectin demonstrated specificity for α-lactose and N-acetyl- d -galactosamine and was able to interact with porcine Stomach Mucin. DlyL2 has 0.78 % carbohydrates in its composition, therefore can be considered a glycoprotein. In addition, its hemagglutinating activity remained stable at a temperature of 90 °C and in a pH range from 5 to 10. Metal chelation treatment did not affect DlyL2 activity suggesting it's not a metalloprotein. Dlyl2 showed an apparent mass of 31 kDa and average molecular mass of 26.371 kDa. Primary structure data could be generated from the partial amino acid sequence of DlyL2, with about 192 residues sequenced by a combination of Edman degradation and tandem mass spectrometry. The lectin is similar to other type II lectins from Diocleinae subtribe, as well as lectins derived from species of more ancient tribes of the Fabaceae family. In addition, DlyL2 exhibited no toxicity to Artemia sp. nauplii. The present study expands the knowledge about the specificity, structural and physicochemical properties of Diocleinae type II lectins.
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h 3 a new lectin from the marine sponge haliclona caerulea purification and mass spectrometric characterization
The International Journal of Biochemistry & Cell Biology, 2013Co-Authors: Rômulo Farias Carneiro, Kyria S. Nascimento, Arthur Alves De Melo, Raniere Da Mata Moura, Alexandra Sampaio De Almeida, Renata Pinheiro Chaves, Bruno L Sousa, Silvana Saker Sampaio, Joao Paulo Matos Santos Lima, Benildo Sousa CavadaAbstract:Abstract A new lectin from the marine sponge Haliclona caerulea (H-3) was isolated using a combination of hydrophobic interaction chromatography and ion-exchange chromatography. H-3 is a protein with three distinct bands on SDS-PAGE: 9 kDa, 16 kDa and 18 kDa. Nevertheless, on gel filtration and N-PAGE, H-3 showed a symmetrical peak and a unique band, respectively. Hemagglutinating activity of H-3 was stable at neutral pH and temperatures up to 60 °C. N -Acetylgalactosamine and porcine Stomach Mucin were the most potent inhibitors of H-3. Primary structure of the lectin was determined using tandem mass spectrometry, and it showed no similarity to any members of the animal lectin families. Top down fragmentation revealed some posttranslational modifications in H-3, including glycosylation. The glycan composition of H-3 was determined, and its structure was predicted. Furthermore, H-3 is a blue protein, binding to a chromophore(-597) by weak interactions, and this is the first time that the interaction between one lectin and a natural chromophore has been shown.
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halilectin 1 h 1 and halilectin 2 h 2 two new lectins isolated from the marine sponge haliclona caerulea
Journal of Molecular Recognition, 2013Co-Authors: Rômulo Farias Carneiro, Kyria S. Nascimento, Arthur Alves De Melo, Raniere Da Mata Moura, Fernando Edson Pessoa Do Nascimento, Clareane Avelino Simplicio, B A M Rocha, Silvana Sakersampaio, Sula Salani Mota, Benildo Sousa CavadaAbstract:Two new lectins named Halilectin 1 (H-1) and Halilectin 2 (H-2) were isolated from the marine sponge Haliclona caerulea using a combination of affinity chromatography on stroma fixed onto Sephadex G-25 and cation and anion exchange chromatography. H-1 is a monomeric protein with a molecular mass of 40 kDa estimated using sodium dodecyl sulfate polyacrylamide gel electrophoresis and 15 kDa estimated using a TSK gel. Conversely, H-2 is a homodimeric protein with 15 kDa monomers linked via weak interactions. H-1 more effectively agglutinates trypsinized rabbit erythrocytes, whereas H-2 more effectively agglutinates native rabbit erythrocytes. The hemagglutinating activity of H-1 could be not inhibited by any tested sugars, but H-2 was inhibited by orosomucoid and porcine Stomach Mucin. Neither lectin was dependent on divalent ions. H-1 was stable at basic pH range and temperatures up to 50 °C, whereas H-2 was stable at acid pH range and temperatures up to 80 °C. The H. caerulea lectins exhibited dose-dependent toxicity against Artemia nauplii. Additionally, 76% of the primary structure of H-2 was determined using tandem mass spectrometry to contain a unique amino acid sequence with no similarity to any members of the animal lectin family. Copyright © 2012 John Wiley & Sons, Ltd.
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Isolation and characterization of a new agglutinin from the red marine alga Hypnea cervicornis J. Agardh.
Biochemistry and cell biology = Biochimie et biologie cellulaire, 2006Co-Authors: Kyria S. Nascimento, Eudismar Vale Nunes, Juan J Calvete, Silvana Saker-sampaio, Wladimir Ronald Lobo Farias, Celso Shiniti Nagano, Benildo Sousa Cavada, R F Rodrigues, G.v. Goersch, Alexandre Holanda SampaioAbstract:The biochemical characterization of a new lectin (Hypnea cervicornis agglutinin or HCA) isolated from the Brazilian red alga H. cervicornis is reported. The haemagglutinating activity of the lectin was only inhibited by the glycoprotein porcine Stomach Mucin at a minimum inhibitory concentration of 19 microg x mL(-1). No haemagglutination inhibition was detected after the addition of simple sugars. The MALDI-TOF molecular masses of native and reduced and carbamidomethylated HCA were, respectively, 9196.6 Da and 9988.2 Da, indicating that the primary structure of the protein is crosslinked by 7 disulfide bonds. This unusual structural feature among lectins, along with its N-terminal sequence and amino-acid composition, clearly shows that HCA belongs to a protein family distinct from the isolectins Hypnin A1 and A2 isolated from the related Japanese alga Hypnea japonica. On the other hand, HCA displayed a high degree of similarity to the agglutinin from the Brazilian species Hypnea musciformis. Our data indicate the occurrence of structural diversity among lectins of closely related species living in distant ecosystems, i.e., the Pacific coast of Japan and the Atlantic coast of Brazil, and support the hypothesis that the lectin content (lectinome) might serve as a biomarker for taxonomical purposes.
Thomas A. Waigh - One of the best experts on this subject based on the ideXlab platform.
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Double-Globular Structure of Porcine Stomach Mucin: A Small-Angle X-ray Scattering Study
Biomacromolecules, 2008Co-Authors: Emanuela Di Cola, Gleb E. Yakubov, Thomas A. WaighAbstract:We present evidence from small-angle X-ray scattering synchrotron experiments that porcine Stomach Mucin (MUC6) contains a double-globular comb structure. Analysis of the amino acid sequence of the peptide comb backbone indicates that the globular structure is determined by both the charge and hydrophobicity of the amino acids and the placement of the short hydrophilic carbohydrate side chains (∼2.5 nm). The double-globular structure is, thus, due to a block copolymer type hydrophobic polyampholyte charge instability in contrast to the random copolymer instabilities observed previously with synthetic polyelectrolytes (particularly polystyrene sulfonates). Careful filtering was required to exclude multimonomer aggregates from the X-ray measurements. A double Guinier analysis (Rg ∼ 26 nm) and a double power law fit are consistent with two globules per chain in low salt conditions. The average radius of the globules is ∼10 nm in salt-free condition (double Guinier fit) and the average distance of intrachain ...
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Charge and interfacial behavior of short side-chain heavily glycosylated porcine Stomach Mucin.
Biomacromolecules, 2007Co-Authors: Gleb E. Yakubov, Aristeidis Papagiannopoulos, Elodie Rat, Thomas A. WaighAbstract:The current accepted model for high-molecular-weight gastric Mucins of the MUC family is that they adopt a polydisperse coil conformation in bulk solutions. We develop this model using well-characterized highly purified porcine gastric Mucin and examine the molecules' charge and interfacial adsorption. "Orthana" Mucin has short side-chains, low levels of sialic acid residues, and includes minute amounts of cystine residues that can be responsible for the self-polymerization of Mucin. Atomic force microscopy and transmission electron microscopy are used to examine the interfacial behavior of the Mucin and clearly demonstrate the existence of discrete spherical subunits within the Mucin molecules, with sizes in agreement with static light scattering, dynamic light scattering, and ζ potential measurements. Furthermore images indicate the combs are assembled with a beads on a string conformation; the daisy chain model. Zeta potential measurements establish the polyampholyte nature of the Mucin molecules, which is used to explain their adsorption behavior on similarly charged surfaces.
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Molecular Structure and Rheological Properties of Short-Side-Chain Heavily Glycosylated Porcine Stomach Mucin
Biomacromolecules, 2007Co-Authors: Gleb E. Yakubov, Aristeidis Papagiannopoulos, Elodie Rat, Richard L. Easton, Thomas A. WaighAbstract:The current accepted model for high-molecular-weight gastric Mucins of the MUC family is that they adopt a polydisperse coil conformation in bulk solutions. We develop this model using well-characterized highly purified porcine gastric Mucin Orthana that is genetically close to the human MUC6 type. It has short side chains and low levels of sialic acid residues and includes minute amounts of cysteine residues that, if abundant, can be responsible for the self-polymerization of Mucin. We have established that the Mucin structure in bulk solutions corresponds to a daisy-chain random coil. Dynamic light scattering experiments probe the internal dynamics of globular subunits (individual daisies) at the ∼9 nm length scale, whereas viscosity and light scattering measurements indicate that the size of the whole Mucin chains is much larger, ∼50 nm. The bulk viscosity (η) scales with Mucin concentration (c) in a manner similar to that found for short-side-chain synthetic comb polyelectrolytes and is characterized ...
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Entanglement Coupling in Porcine Stomach Mucin
Langmuir, 2002Co-Authors: Thomas A. Waigh, Aristeidis Papagiannopoulos, A.m. Voice, Rama Bansil, A. P. Unwin, Charles Dewhurst, Bradley S. Turner, Nezam H. AfdhalAbstract:We present data from small angle neutron scattering (SANS) on the polyelectrolyte side chain liquid crystalline phases of porcine Stomach Mucin. There is a polydomain nematic phase at concentrations above the point of brush overlap. Also, the proteoglycans were seen to orient under the influence of a magnetic field at concentrations below which the brushes do not extensively overlap. The field can be used to investigate the nature of the entanglement coupling between the molecules. The structure factor peak scales as c1/3 across the complete concentration range, implying liquidlike behavior (0.4−680 mg/mL). The rheological data present evidence for shear thinning with four regimes: dilute, semidilute, entangled polydomain liquid crystalline, and entangled liquid crystalline. The length and cross-sectional radius of the polymeric brushes could be measured with SANS. Static light scattering and SANS provide evidence for the changes in osmotic compressibility between dilute, semidilute, and entangled brush ...
Kyria S. Nascimento - One of the best experts on this subject based on the ideXlab platform.
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HGA-2, a novel galactoside-binding lectin from the sea cucumber Holothuria grisea binds to bacterial cells
International journal of biological macromolecules, 2014Co-Authors: Arthur Alves De Melo, Silvana Saker-sampaio, Kyria S. Nascimento, Rômulo Farias Carneiro, Winnie De Melo Silva, Raniere Da Mata Moura, Giselle Cristina Silva, Oscarina Viana De Sousa, Jefferson Pablo De Sousa Saboya, Celso Shiniti NaganoAbstract:Abstract A novel lectin, HGA-2, was isolated from the sea cucumber Holothuria grisea . The protein was isolated by a single chromatographic step using a column of Guar Gum as affinity. HGA-2 showed an apparent molecular mass of 17 kDa and 34 kDa under reducing and nonreducing conditions, respectively. The hemagglutinating activity was specific for rabbit erythrocytes, showing no activity for human blood A, B and O. Its hemagglutinating activity was inhibited by carbohydrates containing galactose, with higher affinity for GalNAc and glycoprotein porcine Stomach Mucin (PSM). HGA-2 was stable at pH 6–10, significantly declining at pH 5 and a temperature of 40 °C, with its activity being abolished at 100 °C. The HGA-2 protein was found to be Ca 2+ -dependent; it was highly toxic against Artemia nauplii and able to recognize and agglutinate cells of Escherichia coli . Amino acid sequences of tryptic peptides of HGA-2 strongly suggest that HGA-2 is a member of the C-type lectin family.
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h 3 a new lectin from the marine sponge haliclona caerulea purification and mass spectrometric characterization
The International Journal of Biochemistry & Cell Biology, 2013Co-Authors: Rômulo Farias Carneiro, Kyria S. Nascimento, Arthur Alves De Melo, Raniere Da Mata Moura, Alexandra Sampaio De Almeida, Renata Pinheiro Chaves, Bruno L Sousa, Silvana Saker Sampaio, Joao Paulo Matos Santos Lima, Benildo Sousa CavadaAbstract:Abstract A new lectin from the marine sponge Haliclona caerulea (H-3) was isolated using a combination of hydrophobic interaction chromatography and ion-exchange chromatography. H-3 is a protein with three distinct bands on SDS-PAGE: 9 kDa, 16 kDa and 18 kDa. Nevertheless, on gel filtration and N-PAGE, H-3 showed a symmetrical peak and a unique band, respectively. Hemagglutinating activity of H-3 was stable at neutral pH and temperatures up to 60 °C. N -Acetylgalactosamine and porcine Stomach Mucin were the most potent inhibitors of H-3. Primary structure of the lectin was determined using tandem mass spectrometry, and it showed no similarity to any members of the animal lectin families. Top down fragmentation revealed some posttranslational modifications in H-3, including glycosylation. The glycan composition of H-3 was determined, and its structure was predicted. Furthermore, H-3 is a blue protein, binding to a chromophore(-597) by weak interactions, and this is the first time that the interaction between one lectin and a natural chromophore has been shown.
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halilectin 1 h 1 and halilectin 2 h 2 two new lectins isolated from the marine sponge haliclona caerulea
Journal of Molecular Recognition, 2013Co-Authors: Rômulo Farias Carneiro, Kyria S. Nascimento, Arthur Alves De Melo, Raniere Da Mata Moura, Fernando Edson Pessoa Do Nascimento, Clareane Avelino Simplicio, B A M Rocha, Silvana Sakersampaio, Sula Salani Mota, Benildo Sousa CavadaAbstract:Two new lectins named Halilectin 1 (H-1) and Halilectin 2 (H-2) were isolated from the marine sponge Haliclona caerulea using a combination of affinity chromatography on stroma fixed onto Sephadex G-25 and cation and anion exchange chromatography. H-1 is a monomeric protein with a molecular mass of 40 kDa estimated using sodium dodecyl sulfate polyacrylamide gel electrophoresis and 15 kDa estimated using a TSK gel. Conversely, H-2 is a homodimeric protein with 15 kDa monomers linked via weak interactions. H-1 more effectively agglutinates trypsinized rabbit erythrocytes, whereas H-2 more effectively agglutinates native rabbit erythrocytes. The hemagglutinating activity of H-1 could be not inhibited by any tested sugars, but H-2 was inhibited by orosomucoid and porcine Stomach Mucin. Neither lectin was dependent on divalent ions. H-1 was stable at basic pH range and temperatures up to 50 °C, whereas H-2 was stable at acid pH range and temperatures up to 80 °C. The H. caerulea lectins exhibited dose-dependent toxicity against Artemia nauplii. Additionally, 76% of the primary structure of H-2 was determined using tandem mass spectrometry to contain a unique amino acid sequence with no similarity to any members of the animal lectin family. Copyright © 2012 John Wiley & Sons, Ltd.
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Isolation and characterization of a new agglutinin from the red marine alga Hypnea cervicornis J. Agardh.
Biochemistry and cell biology = Biochimie et biologie cellulaire, 2006Co-Authors: Kyria S. Nascimento, Eudismar Vale Nunes, Juan J Calvete, Silvana Saker-sampaio, Wladimir Ronald Lobo Farias, Celso Shiniti Nagano, Benildo Sousa Cavada, R F Rodrigues, G.v. Goersch, Alexandre Holanda SampaioAbstract:The biochemical characterization of a new lectin (Hypnea cervicornis agglutinin or HCA) isolated from the Brazilian red alga H. cervicornis is reported. The haemagglutinating activity of the lectin was only inhibited by the glycoprotein porcine Stomach Mucin at a minimum inhibitory concentration of 19 microg x mL(-1). No haemagglutination inhibition was detected after the addition of simple sugars. The MALDI-TOF molecular masses of native and reduced and carbamidomethylated HCA were, respectively, 9196.6 Da and 9988.2 Da, indicating that the primary structure of the protein is crosslinked by 7 disulfide bonds. This unusual structural feature among lectins, along with its N-terminal sequence and amino-acid composition, clearly shows that HCA belongs to a protein family distinct from the isolectins Hypnin A1 and A2 isolated from the related Japanese alga Hypnea japonica. On the other hand, HCA displayed a high degree of similarity to the agglutinin from the Brazilian species Hypnea musciformis. Our data indicate the occurrence of structural diversity among lectins of closely related species living in distant ecosystems, i.e., the Pacific coast of Japan and the Atlantic coast of Brazil, and support the hypothesis that the lectin content (lectinome) might serve as a biomarker for taxonomical purposes.
Renata Pinheiro Chaves - One of the best experts on this subject based on the ideXlab platform.
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New lectins from Codium isthmocladum Vickers show unique amino acid sequence and antibiofilm effect on pathogenic bacteria
Journal of Applied Phycology, 2020Co-Authors: Rômulo Farias Carneiro, Renata Pinheiro Chaves, Mayron Alves De Vasconcelos, Philippe Lima Duarte, Suzete Roberta Silva, Ramon Rodrigues Feitosa, Bruno Lopes Sousa, Antônio Willame Alves, Bruno Anderson Matias Rocha, Edson Holanda TeixeiraAbstract:Two new lectins from the green alga Codium isthmocladum (CiL-1 and CiL-2) were isolated. Both lectins could agglutinate human and rabbit erythrocytes. Galactosides and fetuin showed inhibitory effect on CiL-1. CiL-2 was inhibited by GalNAc and porcine Stomach Mucin. CiL-1 was a monomeric protein of 12 kDa, whereas CiL-2 showed 12 kDa in SDS-PAGE and an oligomeric state in gel filtration. MALDI-ToF-MS of CiL-1 revealed a molecular mass of 12.027 ± 5 Da, while CiL-2 showed molecular mass of 12.264 ± 5 Da. Ninety-eight percent of CiL-1’s primary structure was determined consisting of 112 residues placed in two repeated domains with approximately 60% of similarity. CiL-1 showed similarity with hypothetical proteins from aquatic pathogenic fungi. The N-terminal of CiL-2 showed no similarity to CiL-1 or to any known protein. The three-dimensional model of CiL-1 consists of four two-strand β-sheets disposed in a barrel-like arrangement, connected by loops of variable sizes, with a well-structured hydrophobic core. Binding site prediction suggests the existence of two independent monosaccharide binding sites in CiL-1. The lectins showed no antibacterial activity on Gram-positive and Gram-negative bacteria, but they were able to significantly inhibit the biofilm formation from Staphylococcus aureus and Staphylococcus epidermidis.
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Isolation, biochemical characterization and antibiofilm effect of a lectin from the marine sponge Aplysina lactuca
International journal of biological macromolecules, 2017Co-Authors: Rômulo Farias Carneiro, Celso Shiniti Nagano, Renata Pinheiro Chaves, Mayron Alves De Vasconcelos, Paulo Henrique Pinheiro De Lima, Rafael Pereira, Anna Luísa Pereira, Ulisses Pinheiro, Edson Holanda Teixeira, Alexandre Holanda SampaioAbstract:A new lectin was isolated from the marine sponge Aplysina lactuca (ALL) by combining ammonium sulfate precipitation and affinity chromatography on guar gum matrix. ALL showed affinity for the disaccharides α-lactose, β-lactose and lactulose (Ka=12.5, 31.9 and 145.5M-1, respectively), as well as the glycoprotein porcine Stomach Mucin. Its hemagglutinating activity was stable in neutral acid pH values and temperatures below 60°C. ALL is a dimeric protein formed by two covalently linked polypeptide chains. The average molecular mass, as determined by Electrospray Ionization Mass Spectrometry (ESI-MS), was 31,810±2Da. ESI-MS data also indicated the presence of three cysteines involved in one intrachain and one interchain disulfide bond. The partial amino acid sequence of ALL was determined by tandem mass spectrometry. Eight tryptic peptides presented similarity with lectin I isolated from Axinella polypoides. Its secondary structure is predominantly β-sheet, as indicated by circular dichroism (CD) spectroscopy. ALL agglutinated gram-positive and gram-negative bacterial cells, and it were able to significantly reduce the biomass of the bacterial biofilm tested at dose- dependent effect.
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h 3 a new lectin from the marine sponge haliclona caerulea purification and mass spectrometric characterization
The International Journal of Biochemistry & Cell Biology, 2013Co-Authors: Rômulo Farias Carneiro, Kyria S. Nascimento, Arthur Alves De Melo, Raniere Da Mata Moura, Alexandra Sampaio De Almeida, Renata Pinheiro Chaves, Bruno L Sousa, Silvana Saker Sampaio, Joao Paulo Matos Santos Lima, Benildo Sousa CavadaAbstract:Abstract A new lectin from the marine sponge Haliclona caerulea (H-3) was isolated using a combination of hydrophobic interaction chromatography and ion-exchange chromatography. H-3 is a protein with three distinct bands on SDS-PAGE: 9 kDa, 16 kDa and 18 kDa. Nevertheless, on gel filtration and N-PAGE, H-3 showed a symmetrical peak and a unique band, respectively. Hemagglutinating activity of H-3 was stable at neutral pH and temperatures up to 60 °C. N -Acetylgalactosamine and porcine Stomach Mucin were the most potent inhibitors of H-3. Primary structure of the lectin was determined using tandem mass spectrometry, and it showed no similarity to any members of the animal lectin families. Top down fragmentation revealed some posttranslational modifications in H-3, including glycosylation. The glycan composition of H-3 was determined, and its structure was predicted. Furthermore, H-3 is a blue protein, binding to a chromophore(-597) by weak interactions, and this is the first time that the interaction between one lectin and a natural chromophore has been shown.