title: Design and activity of novel lactoferrampin analogues against O157:H7 enterohemorrhagic Escherichia coli.
abstract: Lactoferrampin 265-284 (LFampin 265-284) is a peptide consisting of residues 265-284 of N1-domain of bovine Lactoferrin (LF). This peptide has several cationic groups in the C-terminal lobe, exhibiting an antibacterial activity against a wide range of microorganisms. However, LFampin 265-284 exhibits low antimicrobial activity against the O157:H7 enterohaemorrhagic Escherichia coli (EHEC O157:H7) when compared with Lactoferrin chimera and Lactoferricin. Here, we have designed three analogues of LFampin 265-284 based on the distribution of cationic groups, hydrophobicity, size, and sequence. Analogues were synthesized by solid phase chemistry using Fmoc methodology obtaining peptides with 95% purity. All peptides maintain the ability to adopt helical conformations (checked by circular dichroism spectra and molecular simulations). Some of these analogues exhibited a significant increase in antimicrobial activity by counting colony forming units against EHEC O157:H7 compared to native LFampin 265-284, with MIC of 10 and 40 µM for 264G-D265K and 264G-D265K/S272R, respectively. The incorporation of a GKLI sequence in the N-terminal lobe increased dramatically its antibacterial activity, an effect which has been attributed to the addition of cationic groups in the N-terminal side that may stabilize the helical conformation of the new designed peptides.
authors.affiliation: Grupo de Investigación en Bioquímica y Microbiología (GIBIM), Escuela de Química, Universidad Industrial de Santander, Edificio Camilo Torres 202, Bucaramanga, Colombia.
authors.forename: Jenniffer
authors.initials: J
authors.lastname: Cruz
authors.forename: Claudia
authors.initials: C
authors.lastname: Ortiz
authors.forename: Fanny
authors.initials: F
authors.lastname: Guzmán
authors.forename: Constanza
authors.initials: C
authors.lastname: Cárdenas
authors.forename: Roberto
authors.initials: R
authors.lastname: Fernandez-Lafuente
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Torres
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002417:Cattle; D015195:Drug Design; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000254:growth & development; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D007781:Lactoferrin / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000494:pharmacology*; D010455:Peptides / Q000737:chemistry; D017433:Protein Structure, Secondary; D016415:Sequence Alignment
chemical_list: D000900:Anti-Bacterial Agents; D010446:Peptide Fragments; D010455:Peptides; C502040:lactoferrampin; D007781:Lactoferrin
keywords: EHEC O157:H7; antimicrobial peptides; bovine lactoferrampin; peptide design; synthetic peptides