1. Peptide synthesis

Peptide synthesis refers to the production of peptides. Peptides and proteins are linear polymers of amino acids linked by amide peptide bonds. Amino acids are primary amines that contain an anomeric carbon that is connected to a hydrogen atom (H), an amino (NH3) group, a carboxyl group (COOH) and a variable side group (R) (Figure 1).

Peptides are chemically synthesized by the condensation reaction of the carboxyl group of one amino acid to the amino group of another. The formation of peptide bonds by linking amino acids together dates back to 100 years. The first peptides to be synthesized, including oxytocin and insulin took about 50–60 years

Figure 1. Peptide structure.

C-terminal protecting group and it is a rapid method to separate the growing peptide product from the different reaction mixtures during synthesis.

(Figure 3).

Figure 3.

terminus.

3.1 Solid support

3.2 Protecting groups

groups, namely

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amino acids and formation of peptide.

3. Solid phase synthesis

Peptide bonds created with peptide coupling agents.

DOI: http://dx.doi.org/10.5772/intechopen.90184

These two ways are combined in an exceedingly method known as native chemical tying. LifeTein's customary amide synthesis method uses the solid part. The liquid-phase approach is employed for the synthesis of short peptides, like diand tripeptides, and C-terminally changed peptides, like accelerator substrates

Determination of Substrate Specificity of the Purified Novel Plant Cysteine Protease Solanain…

The important method for the synthesis of peptides in the lab is known as solidphase peptide synthesis (SPPS) [3]. Merrifield [4] developed this method of SPPS which allows the rapid assembly of a peptide chain through successive reactions of amino acid derivatives on an insoluble porous support. Unlike ribosome protein synthesis, artificial synthesis builds peptides in the C to N direction. During solidphase peptide synthesis, each peptide is anchored to an insoluble polymer at the C-

Solid support in SPPS is Polystyrene, a styrene cross-linked with 1–2% divinylbenzene which is a popular carrier resin in SPPS. Other common gel-type supports include polyacrylamide and polyethylene glycol (PEG). Polystyrene is chemically inert under SPSS conditions. The solid support helps in anchoring the

Amino acids contain side chains with different functional groups with different reactivity. Thus different protecting groups are required. A major problem in peptide synthesis is the side reactions due to multiple reactive groups in amino acids. In order to perform peptide formation with minimal side reactions or to protect the functional groups from non-specific reactions reactive groups in the amino acids need to be blocked or protected. For this many chemical groups have been developed that bind to the amino acids and protect it. They are two types of protecting

#### Figure 2.

Coupling of two amino acids in solution. The unprotected amine of one reacts with the unprotected carboxylic acid group of the other to form a peptide bond.

which clearly indicates chemical synthesis of peptides is a difficult task [1]. But advances in protein synthesis today made peptide synthesis easier today which has varied applications in high-throughput biological research and drug development [2] (Figure 2).
