scholarly journals N-acetylneuraminic acid specific lectin and antibacterial activity from the red alga Gracilaria canaliculata Sonder

Algologia ◽  
2021 ◽  
Vol 31 (2) ◽  
pp. 126-140
Author(s):  
Le Dinh Hung ◽  
◽  
Vo Thi Dieu Trang ◽  
Keyword(s):  
Vibrio Parahaemolyticus ◽  
Pathogenic Bacteria ◽  
Antibacterial Agents ◽  
Aqueous Ethanol ◽  
Divalent Cations ◽  
Red Alga ◽  
Acetylneuraminic Acid ◽  
High Affinity ◽  
Sds Page ◽  
Wide Range

A new lectin from the marine red alga Gracilaria canaliculata (GCL) was isolated by a combination of aqueous ethanol extraction, ethanol precipitation, ion exchange and filtration chromatography. Lectin gave a single band with molecular mass of 22,000 Da in both non-reducing and reducing SDS-PAGE conditions, indicating that GCL is a monomeric protein. The hemagglutination activities of GCL were stable over a wide range of pH from 3 to 10, temperature up 60 oC and not affected by either the presence of EDTA or addition of divalent cations. Lectin GCL had high affinity for N-acetylneuraminic acid through interacting with the acetamido group at equatorial C2 position of these sugar residues, suggesting that GCL is specific for N-acetylneuraminic acid. Furthermore, GCL inhibited the growth of human and shrimp pathogenic bacteria, Staphylococcus aureus and Vibrio alginolyticus, although it did not affect the growth of Escherichia coli, Enterobacter cloace, Vibrio parahaemolyticus and V. harveyi. The red alga G. canaliculata may promise to be a source of valuable lectins for application as antibacterial agents.

scholarly journals Characterization of O-glycan binding lectin from the red alga Hydropuntia eucheumatoides

2020 ◽  
Vol 16 (4) ◽  
pp. 687-696
Author(s):  
Le Dinh Hung ◽  
Tran Thi Hai Yen ◽  
Dinh Thanh Trung
Keyword(s):  
Aqueous Ethanol ◽  
Divalent Cations ◽  
Red Alga ◽  
Monomeric Form ◽  
Sds Page ◽  
Wide Range ◽  
The World ◽  
Binding Lectin ◽  
Oligosaccharide Structures

The red alga, Hydropuntia eucheumatoides is one of the algal genera from which agar is commercially extracted, and is the main source of agar in the world. The lectin HEL from the red alga H. eucheumatoides was isolated by a combination of aqueous ethanol extraction, ethanol precipitation, ion exchange and filtration chromatography. Lectin gave a single band with molecular mass of 17,000 Da in both non-reducing and reducing SDS-PAGE conditions, therefore lectin exists in monomeric form. The hemagglutination activities of HEL were stable over a wide range of pH from 3 to 10, temperature up 60 oC and not affected by either the presence of EDTA or addition of divalent cations, indicating that lectin requires no metal for biological activity. The hemagglutination activities of HEL were not inhibited by monosaccharides and glycoproteins, D-glucose, D-mannose, D-galactose, D-xylose, N-acety-D-mannosamine, transferin, fetuin and yeast mannan, but strongly inhibited by monosaccharides containing  acetamido groups at equatorial C2 position, such as N-acetyl-galactosamine, N-acetyl-glucosamine, N-acetyl-neuraminic acid and glycoprotein porcine stomach mucin bearing O-glycans. Thus, lectin is specific for O-glycans and  may recognize the sequences GalNAcαSer/Thr, GalNAc(α1-3)[Fuc(α1-2)]Gal(β1-4)GlcNAc(β1-3)GalNAc- and GluNAc(α1-4)Gal- under interacting with the acetamido groups at equatorial C2 position of the terminal sugar residues in oligosaccharide structures of O-glycans. The red alga H. eucheumatoides could promise to be a source of valuable lectins for application in biochemistry and biomedicine.

scholarly journals High-mannose type N-glycan binding specificity of a novel lectin from the red alga (Betaphycus gelatinus)

2020 ◽  
Vol 17 (4) ◽  
pp. 709-718
Author(s):  
Le Dinh Hung ◽  
Le Thi Doan Thuc
Keyword(s):  
Divalent Cations ◽  
Kappaphycus Alvarezii ◽  
Gel Filtration ◽  
Red Alga ◽  
Exchange Chromatography ◽  
Sds Page ◽  
Wide Range ◽  
Anti Cancer ◽  
High Mannose ◽  
Solieria Filiformis

The red alga, Betaphycus gelatinus is one of carrageenan sources in the world. The lectin from the red alga B. gelatinus was isolated by a combination of aqueous ethanol extraction, ethanol precipitation, ion-exchange chromatography and gel filtration chromatography and was designated as BGL after the specific name of alga. Lectin gave a single band with molecular mass of about 19,000 Da in both non-reducing and reducing SDS-PAGE conditions, therefore lectin exists in monomer form. The hemagglutination activities of BGL were stable over a wide range of pH from 3 to 10, temperature up 60 oC and not affected by either the presence of EDTA or addition of divalent cations, indicating that lectin requires no metal for biological activity. The hemagglutination activities of BGL were not inhibited by monosaccharides and glycoproteins, D-glucose, D-mannose, D-galactose, D-xylose, N-acetyl-galactosamine, N-acetyl-glucosamine, N-acetyl-neuraminic acid, N-acety-D-mannosamine, transferrin and fetuin, but strongly inhibited by glycoproteins bearing high-mannose type N-glycan, such as yeast mannan and porcine thyroglobulin. Lectin BGL is specific for N-glycans and may recognize terminal (α1–3) or (α1–6)-linked mannose residues in structure Man(α1-6)[Man(α1-3)]Man(α1-6)[Man(α1-3)]Man(β1-4)GlcNAc(β1-4)GlcNAc of N-glycans. High-mannose type N-glycan binding specificities of this lectin highly resemble with those of the anti-cancer, anti-virus and anti-bacteria lectins from the red algae, carrageenophytes, including Eucheuma serra (ESA-2), Eucheuma denticulatum (EDA-2), Kappaphycus striatum (KSA-2), Kappaphycus alvarezii (KAA-1 and KAA-2) and Solieria filiformis (SfL1 and SfL2). The red alga B. gelatinus could promise to be a good source of valuable lectins for application in biochemistry and biomedicine.

scholarly journals Zinc Competition among the Intestinal Microbiota

mBio ◽  
2012 ◽  
Vol 3 (4) ◽  
Author(s):  
Lindsay M. Gielda ◽  
Victor J. DiRita
Keyword(s):  
Gastrointestinal Tract ◽  
Campylobacter Jejuni ◽  
Pathogenic Bacteria ◽  
Zinc Transporter ◽  
Zinc Uptake ◽  
Zinc Binding ◽  
Transport Systems ◽  
Content Type ◽  
High Affinity ◽  
Wide Range

ABSTRACT Bioavailable levels of trace metals, such as iron and zinc, for bacterial growth in nature are sufficiently low that most microbes have evolved high-affinity binding and transport systems. The microbe Campylobacter jejuni lives in the gastrointestinal tract of chickens, the principal source of human infection. A high-affinity ABC transporter for zinc uptake is required for Campylobacter survival in chicken intestines in the presence of a normal microbiota but not when chickens are raised with a limited microbiota. Mass spectrometric analysis of cecal contents revealed the presence of numerous zinc-binding proteins in conventional chicks compared to the number in limited-microbiota chicks. The presence of a microbiota results in the production of host zinc-binding enzymes, causing a growth restriction for bacteria that lack the high-affinity zinc transporter. Such transporters in a wide range of pathogenic bacteria make them good targets for the development of broad-spectrum antimicrobials. IMPORTANCE Zinc is an essential trace element for the growth of most organisms. Quantities of zinc inside cells are highly regulated, as too little zinc does not support growth, while too much zinc is toxic. Numerous bacterial cells require zinc uptake systems for growth and virulence. The work presented here demonstrates that the microbiota in the gastrointestinal tract reduces the quantity of zinc. Without a high-affinity zinc transporter, Campylobacter jejuni, a commensal organism of chickens, is unable to replicate or colonize the gastrointestinal tract. This is the first demonstration of zinc competition between microbiota in the gastrointestinal tract of a host. These results could have profound implications in the field of microbial pathogenesis and in our understanding of host metabolism and the microbiota.

scholarly journals Antibacterial Properties of Graphene-Based Nanomaterials

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 737 ◽  
Author(s):  
Parveen Kumar ◽  
Peipei Huo ◽  
Rongzhao Zhang ◽  
Bo Liu
Keyword(s):  
Pathogenic Bacteria ◽  
Antibacterial Agents ◽  
Antibacterial Properties ◽  
Chronic Illnesses ◽  
Antibacterial Materials ◽  
Wide Range ◽  
New Ideas ◽  
Efficient Alternative ◽  
Further Development ◽  
Toxicity Criteria

Bacteria mediated infections may cause various acute or chronic illnesses and antibiotic resistance in pathogenic bacteria has become a serious health problem around the world due to their excessive use or misuse. Replacement of existing antibacterial agents with a novel and efficient alternative is the immediate demand to alleviate this problem. Graphene-based materials have been exquisitely studied because of their remarkable bactericidal activity on a wide range of bacteria. Graphene-based materials provide advantages of easy preparation, renewable, unique catalytic properties, and exceptional physical properties such as a large specific surface area and mechanical strength. However, several queries related to the mechanism of action, significance of size and composition toward bacterial activity, toxicity criteria, and other issues are needed to be addressed. This review summarizes the recent efforts that have been made so far toward the development of graphene-based antibacterial materials to face current challenges to combat against the bacterial targets. This review describes the inherent antibacterial activity of graphene-family and recent advances that have been made on graphene-based antibacterial materials covering the functionalization with silver nanoparticles, other metal ions/oxides nanoparticles, polymers, antibiotics, and enzymes along with their multicomponent functionalization. Furthermore, the review describes the biosafety of the graphene-based antibacterial materials. It is hoped that this review will provide valuable current insight and excite new ideas for the further development of safe and efficient graphene-based antibacterial materials.

Discovery of Antibacterial Agents Inhibiting the Energy-Coupling Factor (ECF) Transporters by Structure-Based Virtual Screening

2020 ◽  
Author(s):  
Eleonora Diamanti ◽  
Inda Setyawati ◽  
Spyridon Bousis ◽  
leticia mojas ◽  
lotteke Swier ◽  
...  
Keyword(s):  
Virtual Screening ◽  
Antibacterial Agents ◽  
Antimicrobial Agents ◽  
Energy Coupling ◽  
Coupling Factor ◽  
Design Synthesis ◽  
Screening Design ◽  
Starting Point ◽  
Wide Range ◽  
Vitamin Uptake

Here, we report on the virtual screening, design, synthesis and structure–activity relationships (SARs) of the first class of selective, antibacterial agents against the energy-coupling factor (ECF) transporters. The ECF transporters are a family of transmembrane proteins involved in the uptake of vitamins in a wide range of bacteria. Inhibition of the activity of these proteins could reduce the viability of pathogens that depend on vitamin uptake. Because of their central role in the metabolism of bacteria and their absence in humans, ECF transporters are novel potential antimicrobial targets to tackle infection. The hit compound’s metabolic and plasma stability, the potency (20, MIC Streptococcus pneumoniae = 2 µg/mL), the absence of cytotoxicity and a lack of resistance development under the conditions tested here suggest that this scaffold may represent a promising starting point for the development of novel antimicrobial agents with an unprecedented mechanism of action.<br>

A Review on Quantum Dots: Synthesis to In- silico Analysis as Next Generation Antibacterial Agents

2019 ◽  
Vol 20 (3) ◽  
pp. 255-262 ◽  
Author(s):  
Sounik Manna ◽  
Munmun Ghosh ◽  
Ranadhir Chakraborty ◽  
Sudipto Ghosh ◽  
Santi M. Mandal
Keyword(s):  
Quantum Dots ◽  
Pathogenic Bacteria ◽  
Antibacterial Agents ◽  
Antimicrobial Properties ◽  
Binding Potential ◽  
Antibacterial Drug ◽  
Next Generation ◽  
Mechanism Of Reaction ◽  
High Level ◽  
Membrane Components

Succumbing to Multi-Drug Resistant (MDR) bacteria is a great distress to the recent health care system. Out of the several attempts that have been made to kill MDR pathogens, a few gained short-lived success. The failures, of the discovered or innovated antimicrobials, were mostly due to their high level of toxicity to hosts and the phenomenal rate of developing resistance by the pathogens against the new arsenal. Recently, a few quantum dots were tested against the pathogenic bacteria and therefore, justified for potential stockpiling of next-generation antibacterial agents. The key players for antimicrobial properties of quantum dots are considered to be Reactive Oxygen Species (ROS). The mechanism of reaction between bacteria and quantum dots needs to be better understood. They are generally targeted towards the cell wall and membrane components as lipoteichoic acid and phosphatidyl glycerol of bacteria have been documented here. In this paper, we have attempted to simulate ZnS quantum dots and have analysed their mechanism of reaction as well as binding potential to the above bacterial membrane components using CDOCKER. Results have shown a high level of antibacterial activity towards several pathogenic bacteria which specify their potentiality for future generation antibacterial drug development.

scholarly journals Rheology and Water Absorption Properties of Alginate–Soy Protein Composites

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1807
Author(s):  
Estefanía Álvarez-Castillo ◽  
José Manuel Aguilar ◽  
Carlos Bengoechea ◽  
María Luisa López-Castejón ◽  
Antonio Guerrero
Keyword(s):  
Soy Protein ◽  
Water Solubility ◽  
Divalent Cations ◽  
Low Cost ◽  
Soy Protein Isolate ◽  
Protein Isolate ◽  
Guluronic Acid ◽  
Wide Range ◽  
Anionic Polysaccharides ◽  
Porous Matrices

Composite materials based on proteins and carbohydrates normally offer improved water solubility, biodegradability, and biocompatibility, which make them attractive for a wide range of applications. Soy protein isolate (SPI) has shown superabsorbent properties that are useful in fields such as agriculture. Alginate salts (ALG) are linear anionic polysaccharides obtained at a low cost from brown algae, displaying a good enough biocompatibility to be considered for medical applications. As alginates are quite hydrophilic, the exchange of ions from guluronic acid present in its molecular structure with divalent cations, particularly Ca2+, may induce its gelation, which would inhibit its solubilization in water. Both biopolymers SPI and ALG were used to produce composites through injection moulding using glycerol (Gly) as a plasticizer. Different biopolymer/plasticizer ratios were employed, and the SPI/ALG ratio within the biopolymer fraction was also varied. Furthermore, composites were immersed in different CaCl2 solutions to inhibit the amount of soluble matter loss and to enhance the mechanical properties of the resulting porous matrices. The main goal of the present work was the development and characterization of green porous matrices with inhibited solubility thanks to the gelation of alginate.

scholarly journals Beehive Products as Antibacterial Agents: A Review

Antibiotics ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 717
Author(s):  
Rita Abou Nader ◽  
Rawan Mackieh ◽  
Rim Wehbe ◽  
Dany El El Obeid ◽  
Jean Marc Sabatier ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Honey Bee ◽  
Antibacterial Agents ◽  
Royal Jelly ◽  
Biological Activities ◽  
Vital Role ◽  
Bee Venom ◽  
Bacterial Strains ◽  
Wide Range ◽  
Life Threatening

Honeybees are one of the most marvelous and economically beneficial insects. As pollinators, they play a vital role in every aspect of the ecosystem. Beehive products have been used for thousands of years in many cultures for the treatment of various diseases. Their healing properties have been documented in many religious texts like the Noble Quran and the Holy Bible. Honey, bee venom, propolis, pollen and royal jelly all demonstrated a richness in their bioactive compounds which make them effective against a variety of bacterial strains. Furthermore, many studies showed that honey and bee venom work as powerful antibacterial agents against a wide range of bacteria including life-threatening bacteria. Several reports documented the biological activities of honeybee products but none of them emphasized on the antibacterial activity of all beehive products. Therefore, this review aims to highlight the antibacterial activity of honey, bee venom, propolis, pollen and royal jelly, that are produced by honeybees.

scholarly journals Identification of an N-acetylneuraminic acid-presenting bacteria isolated from a human microbiome

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Zhen Han ◽  
Peter S. Thuy-Boun ◽  
Wayne Pfeiffer ◽  
Vincent F. Vartabedian ◽  
Ali Torkamani ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Human Microbiome ◽  
Host Immunity ◽  
Rrna Gene ◽  
Metabolic Labeling ◽  
Selective Labeling ◽  
Fecal Microbiome ◽  
Acetylneuraminic Acid ◽  
Intestinal Mucus ◽  
Microbial Systems

AbstractN-Acetylneuraminic acid is the most abundant sialic acid (SA) in humans and is expressed as the terminal sugar on intestinal mucus glycans. Several pathogenic bacteria harvest and display host SA on their own surfaces to evade Siglec-mediated host immunity. While previous studies have identified bacterial enzymes associated with SA catabolism, no reported methods permit the selective labeling, tracking, and quantitation of SA-presenting microbes within complex multi-microbial systems. We combined metabolic labeling, click chemistry, 16S rRNA gene, and whole-genome sequencing to track and identify SA-presenting microbes from a cultured human fecal microbiome. We isolated a new strain of Escherichia coli that incorporates SA onto its own surface and encodes for the nanT, neuA, and neuS genes necessary for harvesting and presenting SA. Our method is applicable to the identification of SA-presenting bacteria from human, animal, and environmental microbiomes, as well as providing an entry point for the investigation of surface-expressed SA-associated structures.

scholarly journals One-step preparation of antimicrobial silicone materials based on PDMS and salicylic acid: insights from spatially and temporally resolved techniques

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Luca Barbieri ◽  
Ioritz Sorzabal Bellido ◽  
Alison J. Beckett ◽  
Ian A. Prior ◽  
Jo Fothergill ◽  
...  
Keyword(s):  
Salicylic Acid ◽  
Laser Scanning ◽  
Pathogenic Bacteria ◽  
Pharmaceutical Products ◽  
Laser Scanning Microscopy ◽  
Wound Dressings ◽  
Confocal Laser ◽  
Vis Spectroscopy ◽  
Wide Range ◽  
One Step

AbstractIn this work, we introduce a one-step strategy that is suitable for continuous flow manufacturing of antimicrobial PDMS materials. The process is based on the intrinsic capacity of PDMS to react to certain organic solvents, which enables the incorporation of antimicrobial actives such as salicylic acid (SA), which has been approved for use in humans within pharmaceutical products. By combining different spectroscopic and imaging techniques, we show that the surface properties of PDMS remain unaffected while high doses of the SA are loaded inside the PDMS matrix. The SA can be subsequently released under physiological conditions, delivering a strong antibacterial activity. Furthermore, encapsulation of SA inside the PDMS matrix ensured a diffusion-controlled release that was tracked by spatially resolved Raman spectroscopy, Attenuated Total Reflectance IR (ATR-IR), and UV-Vis spectroscopy. The biological activity of the new material was evaluated directly at the surface and in the planktonic state against model pathogenic bacteria, combining confocal laser scanning microscopy, electron microscopy, and cell viability assays. The results showed complete planktonic inhibition for clinically relevant strains of Staphylococcus aureus and Escherichia coli, and a reduction of up to 4 orders of magnitude for viable sessile cells, demonstrating the efficacy of these surfaces in preventing the initial stages of biofilm formation. Our approach adds a new option to existing strategies for the antimicrobial functionalisation of a wide range of products such as catheters, wound dressings and in-dwelling medical devices based on PDMS.

Sign in / Sign up

Export Citation Format

Share Document