Bactericidal kinetics of 3 lactoferricins against Staphylococcus aureus and Escherichia coli.
Bovine lactoferricin is an antimicrobial, cationic peptide generated upon gastric pepsin cleavage of bovine lactoferrin. We investigated the bactericidal effects of native lactoferricin [Lfcin B(17-41)], a shortened derivative [Lfcin B(17-31)] and the all-D-amino acid counterpart of Lfcin B(17-31) against Escherichia coli and Staphylococcus aureus. The results revealed different activities for the peptides against Gram-positive and -negative bacteria. D-Lfcin B(17-31) was the most efficient peptide against E. coli. The same peptide showed improved activity against S. aureus, D-Lfcin B(17-31) showed a significant better efficacy when compared to the L-form, but not when compared to Lfcin B(17-41). There was no correlation between the bactericidal concentrations and the time needed to achieve maximum effect. This indicates the importance of structural differences between the peptides and/or bacteria and implies that the simple thesis of I antibacterial target is not valid for lactoferricin.
Ulvatne
H
H
Department of Medical Microbiology, University and University Hospital of Tromsø, Norway.
Vorland
L H
LH
D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002417:Cattle; D004926:Escherichia coli / Q000187:drug effects*; D007700:Kinetics; D007781:Lactoferrin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests; D010455:Peptides; D020539:Sequence Analysis, Protein; D013211:Staphylococcus aureus / Q000187:drug effects*
D000900:Anti-Bacterial Agents; D010455:Peptides; C082171:lactoferricin B; D007781:Lactoferrin