Browse
Submit Data
Databases
API
Help

Dataset Information

22 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Automated Solution-Phase Synthesis of β-1,4-Mannuronate and β-1,4-Mannan.

ABSTRACT: The first automated solution-phase synthesis of β-1,4-mannuronate and β-1,4-mannan oligomers has been accomplished by using a β-directing C-5 carboxylate strategy. By utilizing fluorous-tag assisting purification after repeated reaction cycles, β-1,4-mannuronate was synthesized up to a hexasaccharide with limited loading of a glycosyl donor (up to 3.5 equiv) for each glycosylation cycle due to the homogeneous solution-phase reaction condition. After a global reduction of the uronates, the β-1,4-mannan hexasaccharide was obtained, thereby demonstrating a new approach to β-mannan synthesis.

SUBMITTER: Tang SL

PROVIDER: S-EPMC4460921 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Automated fluorous-assisted solution-phase synthesis of β-1,2-, 1,3-, and 1,6-mannan oligomers.

Project description:Automated solution-phase syntheses of β-1,2-, 1,3-, and 1,6-mannan oligomers have been accomplished by applying a β-directing C-5 carboxylate strategy. Fluorous-tag-assisted purification after each reaction cycle allowed the synthesis of short β-mannan oligomers with limited loading of glycosyl donor-as low as 3.0 equivalents for each glycosylation cycle. This study showed the capability of the automated solution-phase synthesis protocol for synthesizing various challenging glycosides, including use of a C-5 ester as a protecting group that could be converted under reductive conditions to a hydroxymethyl group for chain extension.

| S-EPMC4893899 | biostudies-literature

Three-dimensional structure of (1,4)-beta-D-mannan mannanohydrolase from tomato fruit.

Project description:The three-dimensional crystal structure of tomato (Lycopersicon esculentum) beta-mannanase 4a (LeMAN4a) has been determined to 1.5 A resolution. The enzyme adopts the (beta/alpha)(8) fold common to the members of glycohydrolase family GH5. The structure is comparable with those of the homologous Trichoderma reesei and Thermomonospora fusca beta-mannanases: There is a conserved three-stranded beta-sheet located near the N terminus that stacks against the central beta-barrel at the end opposite the active site. Three noncanonical beta-helices surround the active site. Similar helices are found in T. reesei but not T. fusca beta-mannanase. By analogy with other beta-mannanases, the catalytic acid/base residue is E204 and the nucleophile residue is E318. The active site cleft of L. esculentum beta-mannanase most closely resembles that of the T. reesei isozyme. A model of substrate binding in LeMAN4a is proposed in which the mannosyl residue occupying the -1 subsite of the enzyme adopts the (1)S(5) skew-boat conformation.

| S-EPMC2253274 | biostudies-literature

Solution-phase automated synthesis of an ?-amino aldehyde as a versatile intermediate.

Project description:A solution-phase automated synthesis of the versatile synthetic intermediate, Garner's aldehyde, was demonstrated. tert-Butoxycarbonyl (Boc) protection, acetal formation, and reduction of the ester to the corresponding aldehyde were performed utilizing our originally developed automated synthesizer, ChemKonzert. The developed procedure was also useful for the synthesis of Garner's aldehyde analogues possessing fluorenylmethyloxycarbonyl (Fmoc) or benzyloxycarbonyl (Cbz) protection.

| S-EPMC5301908 | biostudies-literature

Automated Solution-Phase Synthesis of S-Glycosides for the Production of Oligomannopyranoside Derivatives.

Project description:Thioglycosides are more resistant to enzymatic hydrolysis than their O-linked counterparts, thereby becoming attractive targets for carbohydrate-based therapeutic development. We report the first development of methods for the site-selective incorporation of S-linkages into automated solution-phase oligosaccharide protocols. The protocols were shown to be compatible with the formation of S- or O-glycosides for the synthesis of mannopyranoside trimmers that incorporate both S- and O-linkages to allow the selective incorporation of an S-glycoside in various stages in an automated program.

| S-EPMC7493207 | biostudies-literature

Mannan endo-1,4-β-mannosidase from Kitasatospora sp. isolated in Indonesia and its potential for production of mannooligosaccharides from mannan polymers.

Project description:Mannan endo-1,4-β-mannosidase (commonly known as β-mannanase) catalyzes a random cleavage of the β-D-1,4-mannopyranosyl linkage in mannan polymers. The enzyme has been utilized in biofuel production from lignocellulose biomass, as well as in production of mannooligosaccharides (MOS) for applications in feed and food industries. We aimed to obtain a β-mannanase, for such mannan polymer utilization, from actinomycetes strains isolated in Indonesia. Strains exhibiting high mannanase activity were screened, and one strain belonging to the genus Kitasatospora was selected. We obtained a β-mannanase from this strain, and an amino acid sequence of this Kitasatospora β-mannanase showed a 58-71% similarity with the amino acid sequences of Streptomyces β-mannanases. The Kitasatospora β-mannanase showed a significant level of activity (944 U/mg) against locust bean gum (0.5% w/v) and a potential for oligosaccharide production from various mannan polymers. The β-mannanase might be beneficial particularly in the enzymatic production of MOS for applications of mannan utilization.

| S-EPMC5438323 | biostudies-literature

Hydrolysis of (1,4)-beta-D-mannans in barley (Hordeum vulgare L.) is mediated by the concerted action of (1,4)-beta-D-mannan endohydrolase and beta-D-mannosidase.

Project description:A family GH5 (family 5 glycoside hydrolase) (1,4)-beta-D-mannan endohydrolase or beta-D-mannanase (EC 3.2.1.78), designated HvMAN1, has been purified 300-fold from extracts of 10-day-old barley (Hordeum vulgare L.) seedlings using ammonium sulfate fractional precipitation, followed by ion exchange, hydrophobic interaction and size-exclusion chromatography. The purified HvMAN1 is a relatively unstable enzyme with an apparent molecular mass of 43 kDa, a pI of 7.8 and a pH optimum of 4.75. The HvMAN1 releases Man (mannose or D-mannopyranose)-containing oligosaccharides of degree of polymerization 2-6 from mannans, galactomannans and glucomannans. With locust-bean galactomannan and mannopentaitol as substrates, the enzyme has K(m) constants of 0.16 mg x ml(-1) and 5.3 mM and kcat constants of 12.9 and 3.9 s(-1) respectively. Product analyses indicate that transglycosylation reactions occur during hydrolysis of (1,4)-beta-D-manno-oligosaccharides. The complete sequence of 374 amino acid residues of the mature enzyme has been deduced from the nucleotide sequence of a near full-length cDNA, and has allowed a three-dimensional model of the HvMAN1 to be constructed. The barley HvMAN1 gene is a member of a small (1,4)-beta-D-mannan endohydrolase family of at least six genes, and is transcribed at low levels in a number of organs, including the developing endosperm, but also in the basal region of young roots and in leaf tips. A second barley enzyme that participates in mannan depolymerization through its ability to hydrolyse (1,4)-beta-D-manno-oligosaccharides to Man is a family GH1 beta-D-mannosidase, now designated HvbetaMANNOS1, but previously identified as a beta-D-glucosidase [Hrmova, MacGregor, Biely, Stewart and Fincher (1998) J. Biol. Chem. 273, 11134-11143], which hydrolyses 4NP (4-nitrophenyl) beta-D-mannoside three times faster than 4NP beta-D-glucoside, and has an action pattern typical of a (1,4)-beta-D-mannan exohydrolase.

| S-EPMC1570163 | biostudies-literature

<i>Natronoglomus mannanivorans</i> gen. nov., sp. nov., beta-1,4-mannan utilizing natronoarchaea from hypersaline soda lakes.

Project description:Beta-mannans are insoluble plant polysaccharides with beta-1,4-linked mannose as the backbone. We used three forms of this polysaccharide, namely, pure mannan, glucomannan, and galactomannan, to enrich haloarchaea, which have the ability to utilize mannans for growth. Four mannan-utilizing strains obtained in pure cultures were closely related to each other on the level of the same species. Furthermore, another strain selected from the same habitats with a soluble beta-1,4-glucan (xyloglucan) was also able to grow with mannan. The phylogenomic analysis placed the isolates into a separate lineage of the new genus level within the family Natrialbaceae of the class Halobacteria. The strains are moderate alkaliphiles, extremely halophilic, and aerobic saccharolytics. In addition to the three beta-mannan forms, they can also grow with cellulose, xylan, and xyloglucan. Functional genome analysis of two representative strains demonstrated the presence of several genes coding for extracellular endo-beta-1,4-mannanase from the GH5_7 and 5_8 subfamilies and the GH26 family of glycosyl hydrolases. Furthermore, a large spectrum of genes encoding other glycoside hydrolases that were potentially involved in the hydrolysis of cellulose and xylan were also identified in the genomes. A comparative genomics analysis also showed the presence of similar endo-beta-1,4-mannanase homologs in the cellulotrophic genera Natronobiforma and Halococcoides. Based on the unique physiological properties and the results of phylogenomic analysis, the novel mannan-utilizing halolarchaea are proposed to be classified into a new genus and species Natronoglomus mannanivorans gen. nov., sp. nov. with the type strain AArc-m2/3/4 (=JCM 34861=UQM 41565).

| S-EPMC10963439 | biostudies-literature

Automated Solution-Phase Synthesis of Insect Glycans to Probe the Binding Affinity of Pea Enation Mosaic Virus.

Project description:Pea enation mosaic virus (PEMV)--a plant RNA virus transmitted exclusively by aphids--causes disease in multiple food crops. However, the aphid-virus interactions required for disease transmission are poorly understood. For virus transmission, PEMV binds to a heavily glycosylated receptor aminopeptidase N in the pea aphid gut and is transcytosed across the gut epithelium into the aphid body cavity prior to release in saliva as the aphid feeds. To investigate the role of glycans in PEMV-aphid interactions and explore the possibility of viral control through blocking a glycan interaction, we synthesized insect N-glycan terminal trimannosides by automated solution-phase synthesis. The route features a mannose building block with C-5 ester enforcing a β-linkage, which also provides a site for subsequent chain extension. The resulting insect N-glycan terminal trimannosides with fluorous tags were used in a fluorous microarray to analyze binding with fluorescein isothiocyanate-labeled PEMV; however, no specific binding between the insect glycan and PEMV was detected. To confirm these microarray results, we removed the fluorous tag from the trimannosides for isothermal titration calorimetry studies with unlabeled PEMV. The ITC studies confirmed the microarray results and suggested that this particular glycan-PEMV interaction is not involved in virus uptake and transport through the aphid.

| S-EPMC4640232 | biostudies-literature

Solid phase versus solution phase synthesis of heterocyclic macrocycles.

Project description:Comparing a solution phase route to a solid phase route in the synthesis of the cytotoxic natural product urukthapelstatin A (Ustat A) confirmed that a solid phase method is superior. The solution phase approach was tedious and involved cyclization of a ridged heterocyclic precursor, while solid phase allowed the rapid generation of a flexible linear peptide. Cyclization of the linear peptide was facile and subsequent generation of three oxazoles located within the structure of Ustat A proved relatively straightforward. Given the ease with which the oxazole Ustat A precursor is formed via our solid phase approach, this route is amenable to rapid analog synthesis.

| S-EPMC6269862 | biostudies-literature

Solution-phase synthesis of pyrrole-imidazole polyamides.

Project description:Pyrrole-imidazole polyamides are DNA-binding molecules that are programmable for a large repertoire of DNA sequences. Typical syntheses of this class of heterocyclic oligomers rely on solid-phase methods. Solid-phase methodologies offer rapid assembly on a micromole scale sufficient for biophysical characterizations and cell culture studies. In order to produce gram-scale quantities necessary for efficacy studies in animals, polyamides must be readily synthesized in solution. An 8-ring hairpin polyamide 1, which targets the DNA sequence 5'-WGWWCW-3', was chosen for our synthesis studies as this oligomer exhibits androgen receptor antagonism in cell culture models of prostate cancer. A convergent solution-phase synthesis of 1 from a small set of commercially available building blocks is presented which highlights principles for preparing gram quantities of pyrrole-imidazole oligomers with minimal chromatography.

| S-EPMC2689157 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data