Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 4 de 4
Filter
Add more filters










Database
Language
Publication year range
1.
Biotechnol Bioeng ; 109(4): 992-1006, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22068462

ABSTRACT

Metabolic oligosaccharide engineering (MOE) is a maturing technology capable of modifying cell surface sugars in living cells and animals through the biosynthetic installation of non-natural monosaccharides into the glycocalyx. A particularly robust area of investigation involves the incorporation of azide functional groups onto the cell surface, which can then be further derivatized using "click chemistry." While considerable effort has gone into optimizing the reagents used for the azide ligation reactions, less optimization of the monosaccharide analogs used in the preceding metabolic incorporation steps has been done. This study fills this void by reporting novel butanoylated ManNAc analogs that are used by cells with greater efficiency and less cytotoxicity than the current "gold standard," which are peracetylated compounds such as Ac4 ManNAz. In particular, tributanoylated, N-acetyl, N-azido, and N-levulinoyl ManNAc analogs with the high flux 1,3,4-O-hydroxyl pattern of butanoylation were compared with their counterparts having the pro-apoptotic 3,4,6-O-butanoylation pattern. The results reveal that the ketone-bearing N-levulinoyl analog 3,4,6-O-Bu3 ManNLev is highly apoptotic, and thus is a promising anti-cancer drug candidate. By contrast, the azide-bearing analog 1,3,4-O-Bu3 ManNAz effectively labeled cellular sialoglycans at concentrations ∼3- to 5-fold lower (e.g., at 12.5-25 µM) than Ac4 ManNAz (50-150 µM) and exhibited no indications of apoptosis even at concentrations up to 400 µM. In summary, this work extends emerging structure activity relationships that predict the effects of short chain fatty acid modified monosaccharides on mammalian cells and also provides a tangible advance in efforts to make MOE a practical technology for the medical and biotechnology communities.


Subject(s)
Click Chemistry , Hexosamines/metabolism , Acylation , Adenocarcinoma/pathology , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/toxicity , Apoptosis/drug effects , Azides/analysis , Azides/chemistry , Breast Neoplasms/pathology , Butyric Acid , CHO Cells/drug effects , CHO Cells/metabolism , Cell Cycle/drug effects , Cell Line, Tumor/drug effects , Cell Line, Tumor/metabolism , Cricetinae , Cricetulus , Drug Design , Glycocalyx/metabolism , Glycoconjugates/analysis , Hexosamines/chemical synthesis , Hexosamines/chemistry , Hexosamines/toxicity , Humans , Jurkat Cells/drug effects , Jurkat Cells/metabolism , Ketones/analysis , Molecular Structure , N-Acetylneuraminic Acid/metabolism , Pancreatic Neoplasms/pathology , Structure-Activity Relationship
2.
Curr Protoc Chem Biol ; 2(3): 171-94, 2010 Sep 01.
Article in English | MEDLINE | ID: mdl-23839968

ABSTRACT

Metabolic oligosaccharide engineering (MOE) refers to a technique where non-natural monosaccharide analogs are introduced into living biological systems. Once inside a cell, these compounds intercept a targeted biosynthetic glycosylation pathway and in turn are metabolically incorporated into cell-surface-displayed oligosaccharides where they can modulate a host of biological activities or be exploited as "tags" for bio-orthogonal and chemoselective ligation reactions. Undertaking a MOE experiment can be a daunting task based on the growing repertoire of analogs now available and the ever increasing number of metabolic pathways that can be targeted; therefore, a major emphasis of this article is to describe a general approach for analog design and selection and then provide protocols to ensure safe and efficacious analog usage by cells. Once cell-surface glycans have been successfully remodeled by MOE methodology, the stage is set for probing changes to the myriad cellular responses modulated by these versatile molecules. Curr. Protoc. Chem. Biol. 2:171-194 © 2010 by John Wiley & Sons, Inc.

3.
Glycobiology ; 19(12): 1382-401, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19675091

ABSTRACT

This report provides a perspective on metabolic glycoengineering methodology developed over the past two decades that allows natural sialic acids to be replaced with chemical variants in living cells and animals. Examples are given demonstrating how this technology provides the glycoscientist with chemical tools that are beginning to reproduce Mother Nature's control over complex biological systems - such as the human brain - through subtle modifications in sialic acid chemistry. Several metabolic substrates (e.g., ManNAc, Neu5Ac, and CMP-Neu5Ac analogs) can be used to feed flux into the sialic acid biosynthetic pathway resulting in numerous - and sometime quite unexpected - biological repercussions upon nonnatural sialoside display in cellular glycans. Once on the cell surface, ketone-, azide-, thiol-, or alkyne-modified glycans can be transformed with numerous ligands via bioorthogonal chemoselective ligation reactions, greatly increasing the versatility and potential application of this technology. Recently, sialic acid glycoengineering methodology has been extended to other pathways with analog incorporation now possible in surface-displayed GalNAc and fucose residues as well as nucleocytoplasmic O-GlcNAc-modified proteins. Finally, recent efforts to increase the "druggability" of sugar analogs used in metabolic glycoengineering, which have resulted in unanticipated "scaffold-dependent" activities, are summarized.


Subject(s)
Biomedical Engineering/trends , Carbohydrate Metabolism , Glycomics/trends , N-Acetylneuraminic Acid/physiology , Animals , Biomedical Engineering/methods , Brain/embryology , Brain/growth & development , Brain/metabolism , Carbohydrate Metabolism/physiology , Glycomics/methods , Humans , Models, Biological , N-Acetylneuraminic Acid/metabolism , Polysaccharides/chemical synthesis , Polysaccharides/chemistry , Polysaccharides/metabolism
4.
J Med Chem ; 52(8): 2515-30, 2009 Apr 23.
Article in English | MEDLINE | ID: mdl-19326913

ABSTRACT

This study investigates the breadth of cellular responses engendered by short chain fatty acid (SCFA)-hexosamine hybrid molecules, a class of compounds long used in "metabolic glycoengineering" that are now emerging as drug candidates. First, a "mix and match" strategy showed that different SCFA (n-butyrate and acetate) appended to the same core sugar altered biological activity, complementing previous results [Campbell et al. J. Med. Chem. 2008, 51, 8135-8147] where a single type of SCFA elicited distinct responses. Microarray profiling then compared transcriptional responses engendered by regioisomerically modified ManNAc, GlcNAc, and GalNAc analogues in MDA-MB-231 cells. These data, which were validated by qRT-PCR or Western analysis for ID1, TP53, HPSE, NQO1, EGR1, and VEGFA, showed a two-pronged response where a core set of genes was coordinately regulated by all analogues while each analogue simultaneously uniquely regulated a larger number of genes. Finally, AutoDock modeling supported a mechanism where the analogues directly interact with elements of the NF-kappaB pathway. Together, these results establish the SCFA-hexosamine template as a versatile platform for modulating biological activity and developing new therapeutics.


Subject(s)
Fatty Acids, Volatile/chemical synthesis , Gene Expression/drug effects , Hexosamines/chemical synthesis , Acylation , Apoptosis , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Discovery , Early Growth Response Protein 1/biosynthesis , Early Growth Response Protein 1/genetics , Fatty Acids, Volatile/chemistry , Fatty Acids, Volatile/pharmacology , Gene Expression Profiling , Glucuronidase/biosynthesis , Glucuronidase/genetics , Hexosamines/chemistry , Hexosamines/pharmacology , Humans , Models, Molecular , Mucin-1/biosynthesis , N-Acetylneuraminic Acid/biosynthesis , NF-kappa B/biosynthesis , NF-kappa B/genetics , Oligonucleotide Array Sequence Analysis , Oncogenes , Signal Transduction , Structure-Activity Relationship , Transcription, Genetic , Tumor Suppressor Protein p53/biosynthesis , Tumor Suppressor Protein p53/genetics
SELECTION OF CITATIONS
SEARCH DETAIL
...