Team:REC-CHENNAI/Characterization-Background
CHARACTERIZATION BACKGROUND
Latarcin-2a (GLFG0KLIKKFGRKAISYAVKKARGKH-OH) is a 26 amino acid antimicrobial peptide isolated from the venom of Central Asian spider, Lachesana tarabaevi. It demonstrates lytic activity against Gram-positive and Gram-negative bacteria, yeast and erythrocytes at micromolar concentrations. This peptide, characterised by helix hinge helix structure, upsets the phospholipid association of cell membrane via carpet mechanism. The amphipathically charged peptide orients itself parallel to the membrane axis and disintegrates the lipid layer. The pores, thus created on the membrane, allowing the peptide to make its entry into the cells.
Since the phospholipid composition of cell membranes is a feature of both pathogens and animal cells, Latarcin-2a has shown its potency in penetrating even the membranes of animal cells via the same carpet mechanism, explaining its haemolytic and cytotoxic activity. Therefore, Latarcin-2a has to be made biocompatible without compensating its antimicrobial activity so that it may be used in applications that have close contact with humans.
With literature pointing to the effect that substituting hydrophobic residues at the N-terminal has on reducing haemolytic activity, an F10K point mutation was introduced into Latarcin-2a. The point mutation removed the haemolytic and cytotoxic activity of the peptide while retaining the antimicrobial activity.
Latarcin-2a BBa_K2338001 and Latarcin-2a F10K BBa_K2338003 biobricks have been submitted by the 2017 iGEM team REC-CHENNAI to the Registry of Standard Biological Parts.
