Oligosaccharide
An oligosaccharide (/ˌɑlɪgoʊˈsækəˌɹaɪd/;[1] from the Greek ὀλίγος olígos, "a few", and σάκχαρ sácchar,
"sugar") is a saccharide polymer containing a small number (typically two to ten[2][3][4][5]) of
monosaccharides (simple sugars). Oligosaccharides can have many functions including cell recognition and
cell adhesion.[6]
They are normally present as glycans: oligosaccharide chains are linked to lipids or to compatible amino
acid side chains in proteins, by N- or O-glycosidic bonds. N-Linked oligosaccharides are always
pentasaccharides attached to asparagine via a beta linkage to the amine nitrogen of the side chain.[7]
Alternately, O-linked oligosaccharides are generally attached to threonine or serine on the alcohol group of
the side chain. Not all natural oligosaccharides occur as components of glycoproteins or glycolipids. Some,
such as the raffinose series, occur as storage or transport carbohydrates in plants. Others, such as
maltodextrins or cellodextrins, result from the microbial breakdown of larger polysaccharides such as starch
or cellulose.
Contents
Glycosylation
N-Linked oligosaccharides
O-Linked oligosaccharides
Glycosylated biomolecules
Glycoproteins
Glycolipids
Functions
Cell recognition
Cell adhesion
Dietary oligosaccharides
Sources
See also
References
External links
Glycosylation
In biology, glycosylation is the process by which a carbohydrate is covalently attached to an organic
molecule, creating structures such as glycoproteins and glycolipids.[8]
N-Linked oligosaccharides
N-Linked glycosylation involves oligosaccharide attachment to
asparagine via a beta linkage to the amine nitrogen of the side
chain.[7] The process of N-linked glycosylation occurs
cotranslationally, or concurrently while the proteins is being
translated. Since it is added cotranslationally, it is believed that Nlinked glycosylation helps determine the folding of polypeptides
due to the hydrophilic nature of sugars. All N-linked
oligosaccharides are pentasaccharides: five monosaccharides long.
An example of an N-linked
In N-glycosylation for eukaryotes, the oligosaccharide substrate is
oligosaccharide, shown here with
assembled right at the membrane of the endoplasmatic reticulum.[9]
GlcNAc. X is any amino acid except
For prokaryotes, this process occurs at the plasma membrane. In
proline.
both cases, the acceptor substrate is an asparagine residue. The
asparagine residue linked to an N-linked oligosaccharide usually
occurs in the sequence Asn-X-Ser/Thr,[7] where X can be any amino acid except for proline, although it is
rare to see Asp, Glu, Leu, or Trp in this position.
O-Linked oligosaccharides
Oligosaccharides that participate in O-linked glycosylation are
attached to threonine or serine on the hydroxyl group of the side
chain.[7] O-linked glycosylation occurs in the Golgi apparatus,
where monosaccharide units are added to a complete polypeptide
chain. Cell surface proteins and extracellular proteins are Oglycosylated.[10] Glycosylation sites in O-linked oligosaccharides
are determined by the secondary and tertiary structures of the
polypeptide, which dictate where glycosyltransferases will add
sugars.
An example of an O-linked
oligosaccharide with β-Galactosyl(1n3)-α-N-acetylgalactosaminylSer/Thr.
Glycosylated biomolecules
Glycoproteins and glycolipids are by definition covalently bonded to carbohydrates. They are very
abundant on the surface of the cell, and their interactions contribute to the overall stability of the cell.
Glycoproteins
Glycoproteins have distinct Oligosaccharide structures which have significant effects on many of their
properties,[11] affecting critical functions such as antigenicity, solubility, and resistance to proteases.
Glycoproteins are relevant as cell-surface receptors, cell-adhesion molecules, immunoglobulins, and tumor
antigens.[12]
Glycolipids
Glycolipids are important for cell recognition, and are important for modulating the function of membrane
proteins that act as receptors.[13] Glycolipids are lipid molecules bound to oligosaccharides, generally
present in the lipid bilayer. Additionally, they can serve as receptors for cellular recognition and cell
signaling.[13] The head of the oligosaccharide serves as a binding partner in receptor activity. The binding
mechanisms of receptors to the oligosaccharides depends on the composition of the oligosaccharides that
are exposed or presented above the surface of the membrane. There is great diversity in the binding
mechanisms of glycolipids, which is what makes them such an important target for pathogens as a site for
interaction and entrance.[14] For example, the chaperone activity of glycolipids has been studied for its
relevance to HIV infection.
Functions
Cell recognition
All cells are coated in either glycoproteins or glycolipids, both of which help determine cell types.[7]
Lectins, or proteins that bind carbohydrates, can recognize specific oligosaccharides and provide useful
information for cell recognition based on oligosaccharide binding.
An important example of oligosaccharide cell recognition is the role of glycolipids in determining blood
types. The various blood types are distinguished by the glycan modification present on the surface of blood
cells.[15] These can be visualized using mass spectrometry. The oligosaccharides found on the A, B, and H
antigen occur on the non-reducing ends of the oligosaccharide. The H antigen (which indicates an O blood
type) serves as a precursor for the A and B antigen.[7] Therefore, a person with A blood type will have the
A antigen and H antigen present on the glycolipids of the red blood cell plasma membrane. A person with
B blood type will have the B and H antigen present. A person with AB blood type will have A, B, and H
antigens present. And finally, a person with O blood type will only have the H antigen present. This means
all blood types have the H antigen, which explains why the O blood type is known as the "universal
donor".
How do transport vesicles know the final destination of the protein that they are transporting?
Vesicles are directed by many ways, but the two main ways are:
1. The sorting signals encoded in the amino acid sequence of the proteins.
2. The Oligosaccharide attached to the protein.
The sorting signals are recognised by specific receptors that reside in the membranes or surface coats of
budding vesicles, ensuring that the protein is transported to the appropriate destination.
Cell adhesion
Many cells produce specific carbohydrate-binding proteins known as lectins, which mediate cell adhesion
with oligosaccharides.[16] Selectins, a family of lectins, mediate certain cell–cell adhesion processes,
including those of leukocytes to endothelial cells.[7] In an immune response, endothelial cells can express
certain selectins transiently in response to damage or injury to the cells. In response, a reciprocal selectin–
oligosaccharide interaction will occur between the two molecules which allows the white blood cell to help
eliminate the infection or damage. Protein-Carbohydrate bonding is often mediated by hydrogen bonding
and van der Waals forces.
Dietary oligosaccharides
Fructo-oligosaccharides (FOS), which are found in many vegetables, are short chains of fructose
molecules. They differ from fructans such as inulin, which as polysaccharides have a much higher degree
of polymerization than FOS and other oligosaccharides, but like inulin and other fructans, they are
considered soluble dietary fibre. Using fructo-oligosaccharides (FOS) as fiber supplementations is shown to
have an effect on glucose homeostasis quite similar to insulin.[17] These (FOS) supplementations which can
be considered Prebiotics[18] which produce something called a short-chain fructo-oligosaccharides
(scFOS).[19] Galacto-oligosaccharides (GOS) in particular are used to create a prebiotic effect for infants
that are not being breastfed.[20]
Galactooligosaccharides (GOS), which also occur naturally, consist of short chains of galactose molecules.
Human milk is an example of this and contains oligosaccharides, known as human milk oligosaccharides
(HMOs), which are derived from lactose.[21][22] These oligosaccharides have biological function in the
development of the gut flora of infants. Examples include lacto-N-tetraose, lacto-N-neotetraose, and lactoN-fucopentaose.[21][22] These compounds cannot be digested in the human small intestine, and instead pass
through to the large intestine, where they promote the growth of Bifidobacteria, which are beneficial to gut
health.[23]
HMOs can also protect infants by acting as decoy receptors against viral infection. [24] HMOs accomplish
this by mimicking viral receptors which draws the virus particles away from host cells.[25]Experimentation
has been done to determine how glycan-binding occurs between HMOs and many viruses such as
influenza, rotavirus, human immunodeficiency virus (HIV), and respiratory syncytial virus (RSV).[26] The
strategy HMOs employ could be used to create new antiviral drugs.
[27]
Mannan oligosaccharides (MOS) are widely used in animal feed to improve gastrointestinal health. They
are normally obtained from the yeast cell walls of Saccharomyces cerevisiae. Mannan oligosaccharides
differ from other oligosaccharides in that they are not fermentable and their primary mode of action includes
agglutination of type-1 fimbria pathogens and immunomodulation.[28]
Sources
Oligosaccharides are a component of fibre from plant tissue. FOS and inulin are present in Jerusalem
artichoke, burdock, chicory, leeks, onions, and asparagus. Inulin is a significant part of the daily diet of
most of the world’s population. FOS can also be synthesized by enzymes of the fungus Aspergillus niger
acting on sucrose. GOS is naturally found in soybeans and can be synthesized from lactose. FOS, GOS,
and inulin are also sold as nutritional supplements.
See also
Carbohydrate synthesis – Sub-field of organic chemistry
Oligosaccharide nomenclature – Devising names for a class of carbohydrates
Isomaltooligosaccharide – Mixture of short-chain carbohydrates
References
1. "Definition of OLIGOSACCHARIDE" (https://www.merriam-webster.com/dictionary/oligosacc
haride). www.merriam-webster.com. Retrieved 2018-10-15.
2. Oligosaccharides (https://meshb.nlm.nih.gov/record/ui?name=Oligosaccharides) at the US
National Library of Medicine Medical Subject Headings (MeSH)
3. Walstra P, Wouters JT, Geurts TJ (2008). Dairy Science and Technology (second ed.). CRC,
Taylor & Francis.
4. Whitney E, Rolfes SR (2008). Understanding Nutrition (Eleventh ed.). Thomson Wadsworth..
5. "Oligosaccharide" (https://www.britannica.com/EBchecked/topic/427621/oligosaccharide).
Encyclopædia Britannica.
6. "Molecular Biology of the Cell. 4th edition" (https://www.ncbi.nlm.nih.gov/books/NBK26878/).
Retrieved 16 August 2018.
7. Voet D, Voet J, Pratt C (2013). Fundamentals of Biochemistry: Life at the Molecular Level
(4th ed.). Hoboken, NJ: John Wiley & Sons, Inc. ISBN 978-0470-54784-7..
8. Varki A, ed. (2009). Essentials of Glycobiology (2nd ed.). Cold Spring Harbor Laboratories
Press. ISBN 978-0-87969-770-9..
9. Schwarz F, Aebi M (October 2011). "Mechanisms and principles of N-linked protein
glycosylation". Current Opinion in Structural Biology. 21 (5): 576–82.
doi:10.1016/j.sbi.2011.08.005 (https://doi.org/10.1016%2Fj.sbi.2011.08.005).
PMID 21978957 (https://pubmed.ncbi.nlm.nih.gov/21978957).
10. Peter-Katalinić J (2005). "Methods in enzymology: O-glycosylation of proteins". Methods in
Enzymology. 405: 139–71. doi:10.1016/S0076-6879(05)05007-X (https://doi.org/10.1016%2
FS0076-6879%2805%2905007-X). ISBN 978-0-12-182810-3. PMID 16413314 (https://pub
med.ncbi.nlm.nih.gov/16413314).
11. Goochee CF (1992). "Bioprocess factors affecting glycoprotein oligosaccharide structure".
Developments in Biological Standardization. 76: 95–104. PMID 1478360 (https://pubmed.nc
bi.nlm.nih.gov/1478360).
12. Elbein AD (October 1991). "The role of N-linked oligosaccharides in glycoprotein function".
Trends in Biotechnology. 9 (10): 346–52. doi:10.1016/0167-7799(91)90117-Z (https://doi.or
g/10.1016%2F0167-7799%2891%2990117-Z). PMID 1367760 (https://pubmed.ncbi.nlm.nih.
gov/1367760).
13. Manna M, Róg T, Vattulainen I (August 2014). "The challenges of understanding glycolipid
functions: An open outlook based on molecular simulations". Biochimica et Biophysica Acta
(BBA) - Molecular and Cell Biology of Lipids. 1841 (8): 1130–45.
doi:10.1016/j.bbalip.2013.12.016 (https://doi.org/10.1016%2Fj.bbalip.2013.12.016).
PMID 24406903 (https://pubmed.ncbi.nlm.nih.gov/24406903).
14. Fantini J (2007). "Interaction of proteins with lipid rafts through glycolipid-binding domains:
biochemical background and potential therapeutic applications". Current Medicinal
Chemistry. 14 (27): 2911–7. doi:10.2174/092986707782360033 (https://doi.org/10.2174%2F
092986707782360033). PMID 18045136 (https://pubmed.ncbi.nlm.nih.gov/18045136).
15. Kailemia MJ, Ruhaak LR, Lebrilla CB, Amster IJ (January 2014). "Oligosaccharide analysis
by mass spectrometry: a review of recent developments" (https://www.ncbi.nlm.nih.gov/pmc/
articles/PMC3924431). Analytical Chemistry. 86 (1): 196–212. doi:10.1021/ac403969n (http
s://doi.org/10.1021%2Fac403969n). PMC 3924431 (https://www.ncbi.nlm.nih.gov/pmc/article
s/PMC3924431). PMID 24313268 (https://pubmed.ncbi.nlm.nih.gov/24313268).
16. Feizi T (1993). "Oligosaccharides that mediate mammalian cell–cell adhesion". Current
Opinion in Structural Biology. 3 (5): 701–10. doi:10.1016/0959-440X(93)90053-N (https://doi.
org/10.1016%2F0959-440X%2893%2990053-N).
17. Le Bourgot, Cindy; Apper, Emmanuelle; Blat, Sophie; Respondek, Frédérique (2018-01-25).
"Fructo-oligosaccharides and glucose homeostasis: a systematic review and meta-analysis
in animal models" (https://doi.org/10.1186/s12986-018-0245-3). Nutrition & Metabolism. 15
(1): 9. doi:10.1186/s12986-018-0245-3 (https://doi.org/10.1186%2Fs12986-018-0245-3).
ISSN 1743-7075 (https://www.worldcat.org/issn/1743-7075). PMC 5785862 (https://www.ncb
i.nlm.nih.gov/pmc/articles/PMC5785862). PMID 29416552 (https://pubmed.ncbi.nlm.nih.gov/
29416552).
18. Davani-Davari, Dorna; Negahdaripour, Manica; Karimzadeh, Iman; Seifan, Mostafa;
Mohkam, Milad; Masoumi, Seyed Jalil; Berenjian, Aydin; Ghasemi, Younes (2019-03-09).
"Prebiotics: Definition, Types, Sources, Mechanisms, and Clinical Applications" (https://ww
w.ncbi.nlm.nih.gov/pmc/articles/PMC6463098). Foods (Basel, Switzerland). 8 (3): E92.
doi:10.3390/foods8030092 (https://doi.org/10.3390%2Ffoods8030092). ISSN 2304-8158 (htt
ps://www.worldcat.org/issn/2304-8158). PMC 6463098 (https://www.ncbi.nlm.nih.gov/pmc/art
icles/PMC6463098). PMID 30857316 (https://pubmed.ncbi.nlm.nih.gov/30857316).
19. Respondek, F.; Myers, K.; Smith, T. L.; Wagner, A.; Geor, R. J. (2011). "Dietary
supplementation with short-chain fructo-oligosaccharides improves insulin sensitivity in
obese horses" (https://pubmed.ncbi.nlm.nih.gov/20870952/). Journal of Animal Science. 89
(1): 77–83. doi:10.2527/jas.2010-3108 (https://doi.org/10.2527%2Fjas.2010-3108).
ISSN 1525-3163 (https://www.worldcat.org/issn/1525-3163). PMID 20870952 (https://pubme
d.ncbi.nlm.nih.gov/20870952).
20. Mei, Zhaojun; Yuan, Jiaqin; Li, Dandan (2022). "Biological activity of galactooligosaccharides: A review" (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9485631).
Frontiers in Microbiology. 13: 993052. doi:10.3389/fmicb.2022.993052 (https://doi.org/10.33
89%2Ffmicb.2022.993052). ISSN 1664-302X (https://www.worldcat.org/issn/1664-302X).
PMC 9485631 (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9485631). PMID 36147858
(https://pubmed.ncbi.nlm.nih.gov/36147858).
21. Miesfeld, Roger L. (July 2017). Biochemistry (https://www.worldcat.org/oclc/952277065).
McEvoy, Megan M. (First ed.). New York, NY. ISBN 978-0-393-61402-2. OCLC 952277065
(https://www.worldcat.org/oclc/952277065).
22. "Human Milk Oligosaccharides" (https://www.nestlenutrition-institute.org/resources/hot-topic
s/details/human-milk-oligosaccharides). NNI Global Website. Retrieved 2020-12-04.
23. Moise AM (2017-10-31). The Gut Microbiome: Exploring the Connection between Microbes,
Diet, and Health (https://books.google.com/books?id=0oE5DwAAQBAJ&pg=PA58). ABCCLIO. p. 58. ISBN 978-1-4408-4265-8.
24. Moore, Rebecca E.; Xu, Lianyan L.; Townsend, Steven D. (2021-02-12). "Prospecting
Human Milk Oligosaccharides as a Defense Against Viral Infections" (https://www.ncbi.nlm.n
ih.gov/pmc/articles/PMC7890562). ACS Infectious Diseases. 7 (2): 254–263.
doi:10.1021/acsinfecdis.0c00807 (https://doi.org/10.1021%2Facsinfecdis.0c00807).
ISSN 2373-8227 (https://www.worldcat.org/issn/2373-8227). PMC 7890562 (https://www.ncb
i.nlm.nih.gov/pmc/articles/PMC7890562). PMID 33470804 (https://pubmed.ncbi.nlm.nih.gov/
33470804).
25. Morozov, Vasily; Hansman, Grant; Hanisch, Franz-Georg; Schroten, Horst; Kunz, Clemens
(2018). "Human Milk Oligosaccharides as Promising Antivirals" (https://onlinelibrary.wiley.co
m/doi/10.1002/mnfr.201700679). Molecular Nutrition & Food Research. 62 (6): 1700679.
doi:10.1002/mnfr.201700679 (https://doi.org/10.1002%2Fmnfr.201700679). PMID 29336526
(https://pubmed.ncbi.nlm.nih.gov/29336526).
26. Moore, Rebecca E.; Xu, Lianyan L.; Townsend, Steven D. (2021-02-12). "Prospecting
Human Milk Oligosaccharides as a Defense Against Viral Infections" (https://www.ncbi.nlm.n
ih.gov/pmc/articles/PMC7890562). ACS Infectious Diseases. 7 (2): 254–263.
doi:10.1021/acsinfecdis.0c00807 (https://doi.org/10.1021%2Facsinfecdis.0c00807).
ISSN 2373-8227 (https://www.worldcat.org/issn/2373-8227). PMC 7890562 (https://www.ncb
i.nlm.nih.gov/pmc/articles/PMC7890562). PMID 33470804 (https://pubmed.ncbi.nlm.nih.gov/
33470804).
27. Morozov, Vasily; Hansman, Grant; Hanisch, Franz-Georg; Schroten, Horst; Kunz, Clemens
(2018). "Human Milk Oligosaccharides as Promising Antivirals" (https://onlinelibrary.wiley.co
m/doi/10.1002/mnfr.201700679). Molecular Nutrition & Food Research. 62 (6): 1700679.
doi:10.1002/mnfr.201700679 (https://doi.org/10.1002%2Fmnfr.201700679). PMID 29336526
(https://pubmed.ncbi.nlm.nih.gov/29336526).
28. Smiricky-Tjardes MR, Flickinger EA, Grieshop CM, Bauer LL, Murphy MR, Fahey GC
(October 2003). "In vitro fermentation characteristics of selected oligosaccharides by swine
fecal microflora". Journal of Animal Science. 81 (10): 2505–14.
doi:10.2527/2003.81102505x (https://doi.org/10.2527%2F2003.81102505x).
PMID 14552378 (https://pubmed.ncbi.nlm.nih.gov/14552378).
External links
Media related to Oligosaccharides at Wikimedia Commons
Retrieved from "https://en.wikipedia.org/w/index.php?title=Oligosaccharide&oldid=1118971214"
This page was last edited on 30 October 2022, at 01:32 (UTC).
Text is available under the Creative Commons Attribution-ShareAlike License 3.0; additional terms may apply. By
using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the
Wikimedia Foundation, Inc., a non-profit organization.