Polymer of sugars

The principle that sequences of monomeric subunits are rich in information emerges most fully in the discussion of nucleic acids (Chapter 8). However, proteins and some short polymers of sugars (oligosaccharides) are also information-rich molecules. The amino acid sequence is a form of information that directs the folding of the protein into its unique three-dimensional structure, and ultimately determines the function of the protein. Some oligosaccharides also have unique sequences and three-dimensional structures that are recognized by other macromolecules. 

The molecules called hpids include the fatty adds, which are relatively small molecules compared to the maCTomolecules that are proteins, nucleic acids, and polysaccharides (Voet and Voet, 1995, p. 16). Proteins, of first importance, are polymers of amino adds nucleic acids are polymers of what are called nucleotides and polysaccharides are polymers of sugars.)... 

The three kinds of polymers that are prevalent in nature are polysaccharides, proteins, and nucleic acids. You have already learned about polysaccharides, which are naturally occurring polymers of sugar subunits (Section 22.18), and nucleic acids are covered in Chapter 27. We will now look at proteins and the structurally similar, but shorter, peptides. Peptides and proteins are polymers of amino acids linked together by amide bonds. The repeating units are called amino acid residues. 

A polymer is a molecule that consists of a long chain of small molecules (monomers) that are linked together. The stabilizers used in cream are mostly polysaccharides, i.e. polymers of sugar molecules. Stabilizers have a number of functions, one of which is to increase the viscosity of ice cream mixes. Figure 2.15 shows the viscosity of a typical polymer solution as a function of concentration. The polymer increases the solution viscosity at low concentrations, and, above a certain concentration, the viscosity increases even more rapidly. 

Starch and glycogen are energy-storage polymers of sugars. 

It is. DNA contains two long polymers of sugars (called nucleotides). Attached to each sugar molecule are phosphate groups and a nitrogen base (technically a nucleobase). The sequence of these nucleobases encodes the information in DNA. (For more on DNA, se the Biochemistry chapter.)... 

We observe that carbohydrates are sugars and polymers of sugars used primarily as fuel by organisms (giucose) or as structurai support in piants (ceiiuiose). 

Both starch crops and lignocellulosics contain polymers of sugars that can be broken down into monomers and used in fermentation. The federally-subsidized production of fuel ethanol from com is an example of bioconversion that takes advantage of well-established wet and dry milling techniques after which the starch is enzymatically converted to glucose for yeast fermentation. 

Biological polymers are composed of amino acids, nucleotides, or sugars. Here we describe three types of biological polymers proteins and polypeptides, nucleic acids, and polymers of sugars. 

Polymers of Sugars Polymers of sugars are often called polysaccharides. They are high-molecular-weight (25,000-15,000,000) polymers of monosaccharides. The synthesis of polysaccharides involves the synthesis of hemiacetal and acetal. When an aldehyde reacts with an alcohol, the resulting product is hemiacetal. Upon... 

Polymers are long chains of repeating molecular units called monomers. Polysaccharides are polymers of sugars. Addition polymers form when a radical species attacks a double bond, forming a new. longer radical species that attacks another double bond and so on. 

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