We tends to find safer natural antibacterial substances for food preservation, among which antibacterial peptides and lysozyme are two important natural antibacterial products, both of which can inhibit bacterial growth in a broad spectrum.To expand the iGEM part library, we have introduced multiple new parts designed specifically to suppress bacterial growth. Following an iterative design approach, we developed three main components:
Part 1: Inhibition of bacterial growth using human lysozyme (hLYZ).
Part 2: Inhibition of bacterial growth using the following eight antimicrobial peptides:(Cecropin A, Melittin, Buforin II, LL-37, Plectasin, Hepcidin, Piscidin-1, Lactoferricin)
Part 3: Construction of fusion proteins combining human lysozyme (hLYZ) with the eight antimicrobial peptides to synergistically inhibit bacterial growth.
Finally, through various measurement methods, we aim to identify the most effective antibacterial constructs for application in our product development.
      

Number	Name	Part type	Part type	Part function	Part diagram
BBa_2508RJDQ	pPICZ alpha A	Basic Part	Plasmid_Backbone	pPICZα A is a 3.6 kb Pichia pastoris protein secretion expression vector. The expressed recombinant protein is a fusion protein containing an N-terminal peptide encoding the Saccharomyces cerevisiae alpha-factor secretion signal.
BBa_252QZKWP	hLYZ	Basic Part	Coding	Lysozyme exerts a potent antibacterial effect by hydrolyzing bacterial cell walls, demonstrating particularly high efficacy against Gram-positive bacteria such as Bacillus subtilis.
BBa_25W3IV6V	Cecropin A	Basic Part	Coding	Cecropins are a family of antimicrobial peptides first identified in the Cecropia moth (Hyalophora cecropia). Cecropin A is a principal member of this family and exhibits broad-spectrum antimicrobial activity against bacteria, fungi, and other microorganisms. This nomenclature is well-established in the biological and immunological literature.
BBa_25KMWWNF	Melittin	Basic Part	Coding	Melittin is the primary active component in bee venom, accounting for approximately 50% of its dry weight. It is a small cationic antimicrobial peptide that disrupts the integrity of cell membranes.
BBa_255VLZAT	Buforin II	Basic Part	Coding	Buforin II is a highly potent antimicrobial peptide originally discovered in the gastric tissues of the Asian toad (Bufo bufo gargarizans). It is renowned for its strong antibacterial activity and unique cell membrane-penetrating mechanism.
BBa_25F0UF1O	LL-37	Basic Part	Coding	LL-37 is primarily produced by neutrophils and epithelial cells. It not only kills bacteria, fungi, and viruses but also possesses a variety of functions such as immunomodulation and wound healing.
BBa_253TY9SH	Plectasin	Basic Part	Coding	Plectasin is a peptide antibiotic isolated from the fungus Pseudoplectania nigrella. It has primary, secondary and tertiary structures similar to defensins found in spiders, scorpions, dragonflies and mussels
BBa_25DXW7OG	Hepcidin	Basic Part	Coding	Although hepcidin is a member of the antimicrobial peptide (AMP) family, its primary and central function is to serve as a key regulator of systemic iron homeostasis.
BBa_256I2SA1	Piscidin-1	Basic Part	Coding	Piscidin-1 is a cationic antimicrobial peptide primarily isolated from the mast cells of fish, such as bass. It exhibits potent activity against bacteria, fungi, viruses, and parasites, serving as a key component of the innate immune system in fish.
BBa_2518A7VZ	Lactoferricin	Basic Part	Coding	Lactoferricin is not directly secreted as a peptide, but rather is a bioactive fragment released from lactoferrin through proteolytic hydrolysis (e.g., by pepsin) in the gastric acidic environment. It exhibits significantly more potent antimicrobial activity than its parent protein (lactoferrin), demonstrating efficacy against Gram-positive bacteria, Gram-negative bacteria, fungi, viruses, and even certain cancer cells.
BBa_25YA2AQF	Antisepsis mix	Basic Part	Coding	The product obtained by connecting the above eight antimicrobial peptides through flexible linker (GGGGS).
BBa_25A3W2FJ	pPICZα A/antisepsis mix	Composite Part	Plasmid	Plasmid containing antibacterial peptide antisepsis mix are used to express antibacterial peptide antisepsis mix to exert antibacterial activity.
BBa_25QHRFNC	pPICZα A/Hepcidin	Composite Part	Plasmid	Plasmid containing antibacterial peptide Hepcidin are used to express antibacterial peptide Hepcidin to exert antibacterial activity.
BBa_25QC1Y0D	pPICZα A/Buforin II	Composite Part	Plasmid	Plasmid containing antibacterial peptide Buforin II are used to express antibacterial peptide Buforin II to exert antibacterial activity.
BBa_259RA27S	pPICZα A/Piscidin-1	Composite Part	Plasmid	Plasmid containing antibacterial peptide Piscidin-1 are used to express antibacterial peptide Piscidin-1 to exert antibacterial activity.
BBa_25SIVGES	pPICZα A/LL-37	Composite Part	Plasmid	Plasmid containing antibacterial peptide LL-37 are used to express antibacterial peptide LL-37 to exert antibacterial activity.
BBa_256BXWDZ	pPICZα A/Cecropin A	Composite Part	Plasmid	Plasmid containing antibacterial peptide Cecropin A are used to express antibacterial peptide Cecropin A to exert antibacterial activity.
BBa_256Y7M7S	pPICZα A/Melittin	Composite Part	Plasmid	Plasmid containing antibacterial peptide Melittin are used to express antibacterial peptide Melittin to exert antibacterial activity.
BBa_25Y5S7FX	pPICZα A/Plectasin	Composite Part	Plasmid	Plasmid containing antibacterial peptide Plectasin are used to express antibacterial peptide Plectasin to exert antibacterial activity.
BBa_25I2WEW7	pPICZα A/hLYZ	Composite part	Plasmid	Plasmid containing lysozyme hlYZ are used to express lysozyme hlYZ to exert antibacterial activity.
BBa_25L12B4Z	pPICZα A/Lactoferricin	Composite part	Plasmid	Plasmid containing antibacterial peptide Lactoferricin are used to express antibacterial peptide Lactoferricin to exert antibacterial activity.