Peptides for Antimicrobial Research
Overview
8 research peptides are currently studied for antimicrobial research. This guide ranks them by evidence strength and covers their mechanisms, safety profiles, and current clinical status.
Pexiganan — Phase III (Not Approved)
Evidence Rating: C Category: Antimicrobial / Immune
Pexiganan (MSI-78) is a 22-amino-acid synthetic analog of magainin 2, an antimicrobial peptide originally isolated from the skin of the African clawed frog (Xenopus laevis). It has broad-spectrum bactericidal activity and was developed as a topical cream (Locilex) for infected diabetic foot ulcers. ...
Key claims: Broad-spectrum antibacterial activity; Efficacy in diabetic foot ulcer infections.
Omiganan — Phase III (Not Approved)
Evidence Rating: C Category: Antimicrobial / Immune
Omiganan (MBI 226) is a 12-amino-acid synthetic cationic antimicrobial peptide (sequence: ILRWPWWPWRRK-NH2, MW ~1779 g/mol) derived from indolicidin, a natural antimicrobial peptide from bovine neutrophils. It has been investigated in Phase III clinical trials for prevention of catheter-related infe...
Key claims: Reduces catheter colonization; Topical treatment for papulopustular rosacea.
Brilacidin — Phase II Clinical Trials
Evidence Rating: C Category: Antimicrobial / Immune
Brilacidin (PMX-30063) is a synthetic small-molecule defensin-mimetic (MW ~564 g/mol) developed by Innovation Pharmaceuticals (formerly Cellceutix). It is a peptidomimetic, not a true peptide, designed to mimic the amphipathic structure and antimicrobial mechanism of host defense peptides (defensins...
Key claims: Efficacy in acute bacterial skin infections; Oral mucositis treatment.
Beta-Defensins — Basic Science / Endogenous Reference
Evidence Rating: D Category: Antimicrobial / Immune
Beta-defensins are a family of small cationic antimicrobial peptides (36-45 amino acids, MW ~4-5 kDa) produced by epithelial cells throughout the body. The three best-characterized human beta-defensins are HBD-1 (constitutive), HBD-2 (inducible by infection/inflammation), and HBD-3 (broad-spectrum, ...
Key claims: Broad-spectrum antimicrobial activity; Link innate and adaptive immunity.
Alpha-Defensins — Basic Science / Endogenous Reference
Evidence Rating: D Category: Antimicrobial / Immune
Alpha-defensins are a family of small cationic antimicrobial peptides (29-35 amino acids, MW ~3.5-4.5 kDa) with three characteristic intramolecular disulfide bonds. Human neutrophil peptides (HNP-1 through HNP-4) are stored in azurophilic granules and released during neutrophil degranulation, while ...
Key claims: Critical components of neutrophil antimicrobial defense; HD-6 forms nanonets to trap bacteria.
Lactoferricin — Preclinical Only
Evidence Rating: D Category: Antimicrobial / Immune
Lactoferricin is a 25-amino-acid antimicrobial peptide (f17-41 of bovine lactoferrin; MW ~3126 g/mol for bovine form) generated by pepsin digestion of lactoferrin. Bovine lactoferricin (LfcinB) is substantially more antimicrobially active than the parent protein and exhibits broad-spectrum activity ...
Key claims: Broad-spectrum antimicrobial activity; Anticancer activity in preclinical models.
Melittin — Preclinical / Traditional Use
Evidence Rating: D Category: Antimicrobial / Immune
Melittin is a 26-amino-acid cationic amphipathic peptide (sequence: GIGAVLKVLTTGLPALISWIKRKRQQ, MW ~2846 g/mol) that constitutes approximately 40-60% of dry honeybee (Apis mellifera) venom. It is the principal active component responsible for the pain, inflammation, and hemolytic activity of bee sti...
Key claims: Potent broad-spectrum antimicrobial activity; Anticancer effects in preclinical models.
Histatin-5 — Basic Science / Endogenous Reference
Evidence Rating: D Category: Antimicrobial / Immune
Histatin-5 is a 24-amino-acid histidine-rich cationic peptide (sequence: DSHAKRHHGYKRKFHEKHHSHRGY, MW ~3036 g/mol) found in human saliva. It is the most potent antifungal member of the histatin family, which comprises at least 12 peptides secreted by parotid and submandibular salivary glands. Histat...
Key claims: Potent antifungal activity against Candida species; Unique non-lytic killing mechanism.
