f1: Schematic reaction in kinetically controlled peptide synthesis. An acylated enzyme intermediate (R‐CO‐Enz) reacts either with water (hydrolysis) or with another amino acid (aminolysis). Adapted from Bordusa (2002).

Mentions: The synthesis of peptides is mostly accomplished by chemical or enzymatic means (Guzman et al., 2007). Chemical peptide syntheses can be divided into synthesis in solution and solid‐phase synthesis and are used for the routine production of peptides in the range of about 2–50 residues (Kimmerlin and Seebach, 2005). Especially for the synthesis of small peptides, alternative enzymatic synthesis approaches are used to overcome limitations in chemical synthesis, such as lack of specificity and the high environmental burden (Tramper, 1996; Guzman et al., 2007). Enzyme‐catalyzed reactions give access to a large number of peptides synthesized by different proteases under various conditions (Stehle et al., 1990; Bordusa, 2002; Yokozeki and Hara, 2005; Li and Kanerva, 2006; Heck et al., 2007; Salam et al., 2008) and found industrial interest already in 1988 (Thorbek, 1988). A common approach in the biocatalysis of enzyme‐catalyzed peptide formation is the application of a kinetically controlled process (Jakubke et al., 1985) as illustrated in Fig. 1.