Methods of Obtaining Antimicrobial Peptides

Antimicrobial peptides (AMPs) found in the immune system have advantages over conventional antibiotics. These advantages include a broad spectrum of activity, effectiveness against biofilms, and a mechanism of action that makes them less prone to fast. The production of AMPs can be examined under three main categories.

AMPs are derived from animal, plant, and bacterial sources. However, the marine ecosystem constitutes a particularly rich source of antimicrobial peptides. AMPs obtained from sponges, algae, fish and marine microorganisms are known to exhibit better adaptation to harsh environmental conditions. Plant-derived AMPs display broad-spectrum antimicrobial activity. The first plant-derived AMP is purthionin, originating from wheat. AMPs isolated from various plant root, flower and leaves contain disulfide bonds that support structural stability. Cross-linked disulfide bonds confer high thermal, chemical and enzymatic stability, as well as a tightly packed and dense structure to plant AMPs. Bacteriocins, which are bacterial-derived AMPs, are also effective at low concentrations. Approximately 200 AMPs have been identified from insects. Examples of insect-derived AMPs include attacin, ponericin, drosocin and diptericin.

Chemical synthesis enables the production of both natural and synthetic AMPs. Solid-phase peptide synthesis is the method commonly used for the chemical synthesis of AMPs. The disadvantages include the high concentration of chemical reagents required, the cost of the solid support, and the multi-step repetitive nature of the synthesis process. Due to these limitations, chemical synthesis is not practical for large-scale production.

In addition to chemical synthesis and natural extraction, new methods for AMP production have been developed. The high cost of chemical synthesis and its limited scalability present disadvantages for production. Natural extraction of AMPs is problematic due to the need for repeated isolation of peptides that occur at low concentrations in their natural environment. Moreover, in species with low population densities, extraction poses a risk to method. Therefore, recombinant AMP production, an alternative approach to peptide synthesis, has been emphasized. In recombinant production, natural AMP genes are modified and inserted into mansion organisms according to the principle of heterologous expression. The prokaryote E. coli is the most frequently chosen recombinant bioreactor due to its rapid growth rate and well-characterized expression structure, which facilitates the process. Other commonly used recombinant bioreactors are yeasts such as Saccharomyces cerevisiae and Pichia pastoris. The use of yeasts offers advantages such as relatively low cost, rapid growth and high yield.