Biological macromolecules peptide bond

A polypeptide is a biological macromolecule containing 20 or more amino acids joined by peptide bonds. 

Unlike other biological macromolecules (e.g., DNA), proteins have complex, irregular structures. They are built up by amino acids that are linked by peptide bonds to form a polypeptide chain. We distinguish four levels of protein structure ... 

A polypeptide is a biological macromolecule containing many amino adds, each Problem 27.4 joined to the next by a peptide bond. By convention, the sequence of amino acids... 

One reaction type that merits special consideration is the acylation of amino acids. Other reactions of the amino acids are biologically important. For example, it will be seen later that it is Schiff base formation of the amino function with an aldehyde that provides the basis for all reactions with vitamin (see Chapter 7). However, it is acylation of the amino function of one amino acid with the carboxyl (activated) of another amino acid that leads to formation of the peptide bond and subsequent protein, or polymer formation. It then becomes of interest for the bioorganic chemist to consider and compare the synthesis of the most complex macromolecule in the test tube and the organism. 

Proteins are polymeric biological macromolecules formed by the condensahon of amino acids. The covalent bond between two successive amino acid residues in a protein is called the peptide bond. Hence, what makes each protein unique is the sequential order of the amino acid residues, which can be compared, for instance, to the succession of rosary beads (Fig. 8.1). Because the peptide bond links the carboxyl group of one amino acid to the amino group of the... 

Proteins are the macromolecules responsible for essentially all biological processes. Proteins are composed of aminoacids, which are relatively simple molecules the aminoacids are linked together by peptide bonds. The exact structure of proteins has several levels of complexity, which we will discuss briefly at the end of the present subsection. We consider first the structure of aminoacids and the way in which they are linked to form proteins. 

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