Applications of microscopy and small angle scattering techniques for the characterisation of supramolecular gels

• Connor R. M. MacDonald and
• Emily R. Draper

Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220

Polymer degrading marine Microbulbifer bacteria: an un(der)utilized source of chemical and biocatalytic novelty

• Weimao Zhong and
• Vinayak Agarwal

Beilstein J. Org. Chem. 2024, 20, 1635–1651, doi:10.3762/bjoc.20.146

• not only a wide variety of polysaccharides including cellulose, agar, chitin, alginate, and xylan [8][9][10][11], but also plastics [4][12]. Progressing from their isolation and cultivation, natural product discovery from Microbulbifer bacteria is starting to gather steam [6][13][14]. The major

• the characterization of a purified agarase belonging to the family GH-86 from Microbulbifer bacteria. Alginate lyases The polysaccharide alginate is produced by various seaweeds and bacteria [44]. Two building blocks, β-ᴅ-mannuronic acid (M) and α-ʟ-guluronic acid (G), are used to assemble alginate in

• homo- and heteropolymeric forms. The 1,4-O-linkage in alginate is cleaved by alginate lyases, in a β-elimination manner (Figure 3). Alginate lyases can be either endolyases, or exolyases with preference for polyM or polyG present in the alginate matrix [110]. Alginate lyases have been isolated from

Synthesis of C6-modified mannose 1-phosphates and evaluation of derived sugar nucleotides against GDP-mannose dehydrogenase

• Sanaz Ahmadipour,
• Alice J. C. Wahart,
• Jonathan P. Dolan,
• Laura Beswick,
• Chris S. Hawes,
• Robert A. Field and
• Gavin J. Miller

Beilstein J. Org. Chem. 2022, 18, 1379–1384, doi:10.3762/bjoc.18.142

• pathogen in these cases is mucoid Pseudomonas aeruginosa. Such infections are characterised by overproduction of the exopolysaccharide alginate. We present herein the design and chemoenzymatic synthesis of sugar nucleotide tools to probe a critical enzyme within alginate biosynthesis, GDP-mannose

• evaluation against GMD. Keywords: alginate; chemical probe; enzymatic synthesis; GDP-mannose dehydrogenase; sugar nucleotide; Introduction The opportunistic Gram-negative pathogen, Pseudomonas aeruginosa (PA), becomes the dominant pathogen in patients suffering from cystic fibrosis (CF) and causes a

• chronic respiratory infection that infects more than 80% of those affected [1]. PA strains colonising the respiratory tract in CF undergo a phenomenon known as mucoid conversion, a phenotype characterised by the secretion of copious amounts of the carbohydrate exopolysaccharide alginate. The manifestation

Cryogels: recent applications in 3D-bioprinting, injectable cryogels, drug delivery, and wound healing

• Luke O. Jones,
• Leah Williams,
• Tasmin Boam,
• Martin Kalmet,
• Chidubem Oguike and
• Fiona L. Hatton

Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171

• scaffolds. They further reported the development of 3D-printed cryogels based on alginate with hierarchical structures for hard tissue applications [67]. More recently, in 2018 Serex et al. developed a microfabricated dispensing probe that allowed for the mixing of cryogel monomeric components immediately

• such as antimicrobial properties. A work reported by Koshy et al. in 2018 was testing the use of injectable nanocomposite cryogels for versatile protein-drug delivery [37]. Injectable and porous cryogels were prepared using a bio-orthogonal click chemistry crosslinking approach with alginate employing

• tetrazine-norbornene coupling. Laponite nanoparticles were then incorporated within the walls of the cryogel. The results showed the so-called “click alginate” was able to produce cryogels with an interconnected porous structure, and high deformability allowing it to be used through a 16-gauge needle. The

Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

Chemical synthesis of C6-tetrazole ᴅ-mannose building blocks and access to a bioisostere of mannuronic acid 1-phosphate

• Eleni Dimitriou and
• Gavin J. Miller

Beilstein J. Org. Chem. 2021, 17, 1527–1532, doi:10.3762/bjoc.17.110

• Eleni Dimitriou Gavin J. Miller Lennard-Jones Laboratory, School of Chemical and Physical Sciences, Keele University, Keele, Staffordshire, ST5 5BG, U. K. 10.3762/bjoc.17.110 Abstract Alginate is a biocompatible and industrially relevant polysaccharide that derives many of its important

• -protected donors, suitable for iterative oligosaccharide synthesis. The development of these building blocks is showcased to access anomeric 3-aminopropyl- and 1-phosphate free sugars containing this non-native motif. Keywords: alginate; glycosyl 1-phosphate; non-native monosaccharide; tetrazole; uronate

• ; Introduction Alginate is an important, industrially relevant polysaccharide chemically composed of β-1,4-linked ᴅ-mannuronic acid (M) and α-ʟ-guluronic acid (G) monosaccharide building blocks (Figure 1a). Because of its biocompatibility, alginate has several commercial industrial applications; for example, it

Aqueous olefin metathesis: recent developments and applications

• Valerio Sabatino and
• Thomas R. Ward

Beilstein J. Org. Chem. 2019, 15, 445–468, doi:10.3762/bjoc.15.39

• example of “in water” metathesis with a heterogenous catalytic system. Pauly et al. used alginate beads as a matrix to encapsulate the G-II catalyst for the RCM of substrate 31 and 33 (Scheme 7) [44]. Alginate amide beads perform best in neat water as they facilitate the diffusion of hydrophobic

• substrates through the beads. However, the reaction rates are very low compared to the non-encapsulated catalyst G-II. The main advantage of the catalyst encapsulation is the catalyst recycling, as the alginate beads can be reused up to 10 times, retaining about 80% of activity. Catalysts bearing quaternary

Binding abilities of polyaminocyclodextrins: polarimetric investigations and biological assays

• Marco Russo,
• Daniele La Corte,
• Annalisa Pisciotta,
• Serena Riela,
• Rosa Alduina and
• Paolo Lo Meo

Beilstein J. Org. Chem. 2017, 13, 2751–2763, doi:10.3762/bjoc.13.271

• between our materials and polyanions were investigated by studying the binding with sodium alginate. Finally, the complexation abilities of the same materials towards polynucleotides were assessed by studying their interaction with the model plasmid pUC19. Our results positively highlight the ability of

• CD unit (i.e., 5.7, 6.1 and 4.5 for CD1, CD2 and CD3, respectively). Moreover, we tested the potential ability of these materials to interact with polyanions by studying their behaviour towards sodium alginate (Alg, Figure 1c) chosen as suitable model compound. Finally, we performed some preliminary

• their interaction with sodium alginate (Alg). This is an easily available and stable block copolymer, constituted by β-D-mannuronate and β-L-guluronate units linked by 1→4 glycosidic bridges. Therefore, it seemed an ideal candidate as model polyanion, in order to study the stoichiometric and

Fluorescent carbon dots from mono- and polysaccharides: synthesis, properties and applications

• Stephen Hill and
• M. Carmen Galan

Beilstein J. Org. Chem. 2017, 13, 675–693, doi:10.3762/bjoc.13.67

• CDs. Subsequently in 2014, the same group was able to show that coating of calcium alginate (CA) beads with chitosan hydrogel-based CDs yielded a new nanomaterial that could be employed as a pH-responsive drug-delivery vehicle (Scheme 21) [56]. The CDs were used as a protective layer onto the CA beads

Secondary metabolome and its defensive role in the aeolidoidean Phyllodesmium longicirrum, (Gastropoda, Heterobranchia, Nudibranchia)

• Alexander Bogdanov,
• Cora Hertzer,
• Stefan Kehraus,
• Samuel Nietzer,
• Sven Rohde,
• Peter J. Schupp,
• Heike Wägele and
• Gabriele M. König

Beilstein J. Org. Chem. 2017, 13, 502–519, doi:10.3762/bjoc.13.50

Conjugates of methylated cyclodextrin derivatives and hydroxyethyl starch (HES): Synthesis, cytotoxicity and inclusion of anaesthetic actives

• Lisa Markenstein,
• Antje Appelt-Menzel,
• Marco Metzger and
• Gerhard Wenz

Beilstein J. Org. Chem. 2014, 10, 3087–3096, doi:10.3762/bjoc.10.325

• like chitosane [29], alginate [24] and dextrane [28] is advantageous for the design of drug delivery systems because of the low toxicities and biodegradabilities of those polymers. Among the various coupling reactions, the [2 + 3] cycloaddition of alkynes and azides, the so-called Huisgen reaction [30

An integrated photocatalytic/enzymatic system for the reduction of CO₂ to methanol in bioglycerol–water

• Michele Aresta,
• Angela Dibenedetto,
• Tomasz Baran,
• Antonella Angelini,
• Przemysław Łabuz and
• Wojciech Macyk

Beilstein J. Org. Chem. 2014, 10, 2556–2565, doi:10.3762/bjoc.10.267

• enzymes FateDH, FaldDH, and ADH were encapsulated into silicate cages made from Ca alginate and tetraethoxysilanes (TEOS) and used at a controlled pH of 7. CO2 was admitted in a continuous flow reactor at such a rate to generate a 20% excess with respect to the stoichiometric amount required by the

• )-electron mediator and glycerol as a sacrificial reagent. Beads produced from Ca-alginate and TEOS containing co-encapsulated FateDH, FaldDH and ADH. Assembled photocatalytic/enzymatic system for reduction of CO2 to CH3OH. Acknowledgements We thank the Apulian Region – Project VALBIOR for loan of equipment

Flow synthesis of phenylserine using threonine aldolase immobilized on Eupergit support

• Jagdish D. Tibhe,
• Hui Fu,
• Timothy Noël,
• Qi Wang,
• Jan Meuldijk and
• Volker Hessel

Beilstein J. Org. Chem. 2013, 9, 2168–2179, doi:10.3762/bjoc.9.254

• esterification [27], oxidation and reduction [28], C–C bond formation [29], and polymerization [30]. Recent advancements in the field of enzymatic microreactors include the use of alginate/protamine/silica hybrid capsules with ultrathin membranes [31], monolithic enzyme microreactors [29][32], and biodegradable