Advances in glycoside and oligosaccharide synthesis

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(22), P. 7773 - 7801

Published: Jan. 1, 2023

The structural complexity of glycans poses a serious challenge in the chemical synthesis glycosides, oligosaccharides and glycoconjugates. Glycan complexity, determined by composition, connectivity, configuration far exceeds what nature achieves with nucleic acids proteins. Consequently, glycoside ranks among most complex tasks organic synthesis, despite involving only simple type bond-forming reaction. Here, we introduce fundamental principles bond formation summarize recent advances oligosaccharide synthesis.

Language: Английский

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Particle-attached bacteria act as gatekeepers in the decomposition of complex phytoplankton polysaccharides

Microbiome, Journal Year: 2024, Volume and Issue: 12(1)

Published: Feb. 20, 2024

Abstract Background Marine microalgae (phytoplankton) mediate almost half of the worldwide photosynthetic carbon dioxide fixation and therefore play a pivotal role in global cycling, most prominently during massive phytoplankton blooms. Phytoplankton biomass consists considerable proportions polysaccharides, substantial parts which are rapidly remineralized by heterotrophic bacteria. We analyzed diversity, activity, functional potential such polysaccharide-degrading bacteria different size fractions diverse spring bloom at Helgoland Roads (southern North Sea) high temporal resolution using microscopic, physicochemical, biodiversity, metagenome, metaproteome analyses. Results Prominent active 0.2–3 µm free-living clades comprised Aurantivirga , “Formosa”, Cd . Prosiliicoccus, NS4, NS5, Amylibacter Planktomarina SAR11 Ia, SAR92, SAR86, whereas BD1-7, Stappiaceae Nitrincolaceae Methylophagaceae Sulfitobacter NS9, Polaribacter Lentimonas CL500-3, Algibacter Glaciecola dominated 3–10 > 10 particles. Particle-attached were more exhibited dynamic adaptive shifts over time terms taxonomic composition repertoires encoded polysaccharide-targeting enzymes. In total, 305 species-level metagenome-assembled genomes obtained, including 152 particle-attached bacteria, 100 novel for sampling site with 76 representing new species. Compared to they featured on average larger higher polysaccharide utilization loci. The latter predicted target broader spectrum substrates, ranging from readily soluble, simple structured storage polysaccharides (e.g., laminarin, α-glucans) less complex structural, or secreted xylans, cellulose, pectins). particular, poorly soluble was widespread among abundant Conclusions represented only 1% all bloom-associated yet our data suggest that many played gatekeeping solubilization subsequent degradation numerous important classes algal glycans. diversity niches is determining factor proportion can be generally short-lived events.

Language: Английский

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Fucoid brown algae inject fucoidan carbon into the ocean

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 120(1)

Published: Dec. 30, 2022

Brown algae annually convert gigatons of carbon dioxide into carbohydrates, including the complex extracellular matrix polysaccharide fucoidan. Due to its persistence in environment, fucoidan is potentially a pathway for marine sequestration. Rates secretion by brown remain unknown due challenge identifying and quantifying polysaccharides seawater. We adapted techniques anion exchange chromatography, enzyme-linked immunosorbent assay, biocatalytic enzyme-based assay detection quantification found alga Fucus vesiculosus at Baltic Sea coast south-west Finland secrete 0.3% their biomass as per day. Dissolved concentrations seawater adjacent reached up 0.48 mg L −1 . Fucoidan accumulated during incubations F. , significantly more light than darkness. Maximum estimation acid hydrolysis indicated rate 28 40 C kg h accounting 44 50% all exuded dissolved organic carbon. Composed only carbon, oxygen, hydrogen, sulfur, does not consume nutrients enabling sequestration independent algal growth. Extrapolated over year, sequester secreted biomass. The global utility an alternative removal without need harvest or bury

Language: Английский

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From Microalgae to Bioenergy: Recent Advances in Biochemical Conversion Processes

Fermentation, Journal Year: 2023, Volume and Issue: 9(6), P. 529 - 529

Published: May 29, 2023

Concerns about rising energy demand, fossil fuel depletion, and global warming have increased interest in developing utilizing alternate renewable sources. Among the available resources, microalgae biomass, a third-generation feedstock, is promising for production due to its rich biochemical composition, metabolic elasticity, ability produce numerous bioenergy products, including biomethane, biohydrogen, bioethanol. However, true potential of biomass future economy yet be realized. This review provides comprehensive overview various conversion processes (anaerobic digestion, direct biophotolysis, indirect photo fermentation, dark microalgae-catalyzed traditional alcoholic fermentation by ethanologenic microorganisms) that could adapted transform into different products. Recent advances are compiled critically analyzed, their limitations terms process viability, efficacy, scalability, economic environmental sustainability highlighted. Based on current research stage technological development, biomethane from anaerobic digestion bioethanol identified as methods commercialization microalgae-based bioenergy. significant challenges these technologies’ remain, high costs low recovery efficiency. Future should focus reducing costs, an integrated biorefinery approach, effectively artificial intelligence tools optimization scale-up solve accelerate development

Language: Английский

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Selfish bacteria are active throughout the water column of the ocean

ISME Communications, Journal Year: 2023, Volume and Issue: 3(1)

Published: Feb. 4, 2023

Heterotrophic bacteria in the ocean invest carbon, nitrogen, and energy extracellular enzymes to hydrolyze large substrates smaller sizes suitable for uptake. Since hydrolysis products produced outside of a cell may be lost diffusion, return on this investment is uncertain. Selfish change odds their favor by binding, partially hydrolyzing, transporting polysaccharides into periplasmic space without loss products. We expected selfish most common upper ocean, where phytoplankton produce abundant fresh organic matter, including complex polysaccharides. We, therefore, sampled water western North Atlantic Ocean at four depths from three stations differing physiochemical conditions; these also differed considerably microbial community composition. To our surprise, we found that are throughout column greater than 5500 m. uptake as strategy thus appears geographically-and phylogenetically-widespread. processing require highly sensitive substrate structure, activities might not reflected measurements relying only low molecular weight substrates. Moreover, even bottom supply structurally-intact polysaccharides, therefore enzymatic investment, must sufficient maintain organisms.

Language: Английский

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Alpha-glucans from bacterial necromass indicate an intra-population loop within the marine carbon cycle

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: May 14, 2024

Abstract Phytoplankton blooms provoke bacterioplankton blooms, from which bacterial biomass (necromass) is released via increased zooplankton grazing and viral lysis. While consumption of algal during well-studied, little known about the concurrent recycling these substantial amounts necromass. We demonstrate that biomass, such as alpha-glucan storage polysaccharides, generated organic matter, reused thus itself a major carbon source in vitro diatom-dominated bloom. highlight conserved enzymes binding proteins dominant bloom-responder clades are presumably involved by members community. furthermore corresponding protein machineries can be specifically induced extracted alpha-glucan-rich polysaccharide extracts. This necromass likely constitutes large-scale intra-population energy conservation mechanism keeps dedicated part microbial loop.

Language: Английский

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Taxonomic and functional stability overrules seasonality in polar benthic microbiomes

The ISME Journal, Journal Year: 2024, Volume and Issue: 18(1)

Published: Jan. 1, 2024

Abstract Coastal shelf sediments are hot spots of organic matter mineralization. They receive up to 50% primary production, which, in higher latitudes, is strongly seasonal. Polar and temperate benthic bacterial communities, however, show a stable composition based on comparative 16S rRNA gene sequencing despite different microbial activity levels. Here, we aimed resolve this contradiction by identifying seasonal changes at the functional level, particular with respect algal polysaccharide degradation genes, combining metagenomics, metatranscriptomics, glycan analysis sandy surface from Isfjorden, Svalbard. Gene expressions diverse carbohydrate-active enzymes changed between winter spring. For example, β-1,3-glucosidases (e.g. GH30, GH17, GH16) degrading laminarin, an energy storage molecule algae, were elevated spring, while related α-glucan expressed both seasons maxima GH63, GH13_18, GH15). Also, expression GH23 involved peptidoglycan was prevalent, which line recycling biomass. Sugar extractions bulk low concentrations during but spring samples, glucose constituting largest fraction measured monosaccharides (84% ± 14%). In porewater, ~18-fold than overlying seawater (1107 484 vs. 62 101 μg C l−1) depleted glucose. Our data indicate that communities digest transform labile parts photosynthesis-derived particulate likely release more stable, glucose-depleted residual glycans unknown structures, quantities, residence times into ocean, thus modulating marine coastal waters.

Language: Английский

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Seaweed-derived fucoidans and rhamnan sulfates serve as potent anti-SARS-CoV-2 agents with potential for prophylaxis

Carbohydrate Polymers, Journal Year: 2024, Volume and Issue: 337, P. 122156 - 122156

Published: April 16, 2024

Language: Английский

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Pulsed inputs of high molecular weight organic matter shift the mechanisms of substrate utilisation in marine bacterial communities

Environmental Microbiology, Journal Year: 2024, Volume and Issue: 26(2)

Published: Jan. 22, 2024

Abstract Heterotrophic bacteria hydrolyze high molecular weight (HMW) organic matter extracellularly prior to uptake, resulting in diffusive loss of hydrolysis products. An alternative ‘selfish’ uptake mechanism that minimises this has recently been found be common the ocean. We investigated how HMW addition affects these two processing mechanisms surface and bottom waters at three stations North Atlantic Ocean. A pulse increased cell numbers, as well rate spectrum extracellular enzymatic activities both depths. The effects on selfish were more differentiated: Gulf Stream productive south Newfoundland, structurally simple polysaccharides upon addition. number taking up complex polysaccharides, however, was largely unchanged. In contrast, oligotrophic gyre, despite external rates, unchanged, irrespective polysaccharide structure. deep (> 4000 m), substrates processed only by bacteria. Mechanisms substrate processing—and extent which products are released environment—depend structural complexity resident bacterial community.

Language: Английский

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Characterization of a novel algicidal bacteria Arenibacter sp. strain 6A1 and its application to eliminate harmful algal blooms

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 10

Published: Jan. 31, 2024

Hazardous impacts caused by harmful algal blooms (HABs) have facilitated the development of novel effective approaches for controlling frequent HABs. Recently, bacteria with algicidal effects, as a promising alternative tool eliminating HABs-forming species received wide concerns. In present study, marine bacterial strain 6A1 potent activity was successfully isolated from bloom Akashiwo sanguinea , and characteristics related to its action were systematically investigated. Sequencing results 16S rDNA suggested that this bacterium belongs genus Arenibacter in family Flavobacteriaceae, while phylogenetic analysis revealed sp. only date, according best our knowledge. had an extraordinarily high performance when it added A. culture volume fraction 1.5% 2 h. The concentration-dependent time-dependent. efficacy seen during stationary phase, resistance declined growth cycle progressed. Subsequently, indirect mode verified compounds produced proved be heat-resistant. Further research showed severe damage photosynthesis, oxidative stress, also three algae varying degrees. greatest found on unarmored dinoflagellate followed raphidophyte Chattonella antiqua armored Alexandrium tamarense . exhibited selective range species, primarily targeting Pyrrophyta Ochrophyta. proposed (strain 6A1) can powerful eco-friendly emergency treatment HABs certain coastal water bodies.

Language: Английский

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