TY - JOUR
T1 - Structure and Mechanism of Action of an Indolicidin Peptide Derivative with Improved Activity against Gram-positive Bacteria
AU - Friedrich, Carol L.
AU - Rozek, Annett
AU - Patrzykat, Aleksander
AU - Hancock, Robert E.W.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2001/6/29
Y1 - 2001/6/29
N2 - Indolicidin, an antimicrobial peptide with a unique amino acid sequence (ILPWKWPWWPWRR-NH2) is found in bovine neutrophils. A derivative of indolicidin, CP10A, has alanine residues substituted for proline residues and has improved activity against Gram-positive organisms. Transmission electron microscopy of Staphylococcus aureus and Staphylococcus epidermidis treated with CP10A showed mesosome-like structures in the cytoplasm. The peptide at 2-fold the minimal inhibitory concentration did not show significant killing of S. aureus ISP67 (a histidine, uridine, and thymidine auxotroph) but did show an early effect on histidine and uridine incorporation and, later, an effect on thymidine incorporation. Upon interaction with liposomes, detergents, and lipoteichoic acid, CP10A was shown by circular dichroism spectroscopy to undergo a change in secondary structure. Fluorescence spectroscopy indicated that the tryptophan residues were located at the hydrophobic/hydrophilic interface of liposomes and detergent micelles and were inaccessible to the aqueous quencher EI. The three-dimensional structure of CP10A in the lipid mimetic dodecylphosphocholine was determined using two-dimensional NMR methods and was characterized as a short, amphipathic helical structure, whereas indolicidin was previously shown to have an extended structure. These studies have introduced a cationic peptide with a unique structure and an ability to interact with membranes and to affect intracellular synthesis of proteins, RNA, and DNA.
AB - Indolicidin, an antimicrobial peptide with a unique amino acid sequence (ILPWKWPWWPWRR-NH2) is found in bovine neutrophils. A derivative of indolicidin, CP10A, has alanine residues substituted for proline residues and has improved activity against Gram-positive organisms. Transmission electron microscopy of Staphylococcus aureus and Staphylococcus epidermidis treated with CP10A showed mesosome-like structures in the cytoplasm. The peptide at 2-fold the minimal inhibitory concentration did not show significant killing of S. aureus ISP67 (a histidine, uridine, and thymidine auxotroph) but did show an early effect on histidine and uridine incorporation and, later, an effect on thymidine incorporation. Upon interaction with liposomes, detergents, and lipoteichoic acid, CP10A was shown by circular dichroism spectroscopy to undergo a change in secondary structure. Fluorescence spectroscopy indicated that the tryptophan residues were located at the hydrophobic/hydrophilic interface of liposomes and detergent micelles and were inaccessible to the aqueous quencher EI. The three-dimensional structure of CP10A in the lipid mimetic dodecylphosphocholine was determined using two-dimensional NMR methods and was characterized as a short, amphipathic helical structure, whereas indolicidin was previously shown to have an extended structure. These studies have introduced a cationic peptide with a unique structure and an ability to interact with membranes and to affect intracellular synthesis of proteins, RNA, and DNA.
UR - http://www.scopus.com/inward/record.url?scp=0035968224&partnerID=8YFLogxK
U2 - 10.1074/jbc.M009691200
DO - 10.1074/jbc.M009691200
M3 - Article
C2 - 11294848
AN - SCOPUS:0035968224
SN - 0021-9258
VL - 276
SP - 24015
EP - 24022
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 26
ER -