Dictionary > Nonose

Nonose

Definition
noun, plural: nonoses
A nine-carbon monosaccharide or sugar
Supplement
Monosaccharides are the simplest form of carbohydrates. They are classified according to the number of carbon atoms in a monosaccharide. In particular, a nonose is a monosaccharide with nine carbon atoms. Monosaccharides may also be classified based on the type of carbonyl group they contain. An aldose is a monosaccharide that contains an aldehyde group (-CHO) at position 1 whereas a ketose is one that contains a ketone (C=O) at position 2. Thus, an aldononose would be a nonose with an aldehyde group. A ketononose, in contrast, would be a nonose with a ketone functional group.
Examples of nonoses are neuraminic acid, sialic acid, legionaminic acid, and psudaminic acid.Neuraminic acid name: (4S,5R,6R,7S,8R)-5-amino-4,6,7,8,9-pentahydroxy-2-oxo-nonanoic acid is a nonose with a chemical formula of C9H17NO8. It does not occur naturally. Nevertheless, its derivatives are commonly found in bacteria and animal tissues. For instance, sialic acid refers to any of the N– or O– substituted derivatives of neuraminic acid. The sialic acids are widely distributed in animal tissues and occur as components of oligosaccharide chains of mucins.
Biosynthesis of sialic acid begins by the production of N-acetylglucosamine-6-P via the catalytic action of transferase on glucosamine-6-phosphate and acetyl-CoA. Through epimerization, it is converted to N-acetylmannosamine-6-P that reacts with PEP, resulting in the formation of N-acetylneuraminic-9-P (which is a sialic acid).
In bacteria, sialic acid biosynthesis is carried out by using a mannose derivative. The enzyme aldolase inserts three carbons (from pyruvate) to it, producing sialic acid structure.
Word origin: non(a)– (“nine”) + –ose (relating to sugars)
See also:


You will also like...

Chromosome Mutations
Chromosome Mutations

Mutations can also influence the phenotype of an organism. This tutorial looks at the effects of chromosomal mutations, ..

Young plant growing from the soil.
Soils

Nutrients in the soil are essential to the proper growth of a land plant. This tutorial deals with the properties of soi..

Still Water Community Plants
Still Water Community Plants

This tutorial looks at the adaptations of freshwater plants for them to thrive in still water habitats. Familiarize your..

Regulation of Biological Systems
Regulation of Biological Systems

Regulation of Biological Systems tutorials are focused on the modulation of biological systems from cell to population l..

Plant biology
Plant Biology

Plantlife can be studied at a variety of levels, from the molecular, genetic and biochemical level through organelles, c..

Carbohydrates, fats and proteins - dietary sources
A Balanced Diet – Carbohydrates and Fat

Apart from vitamins, the human body also requires high energy sources such as carbohydrates and fats. If you want an ove..