TY - JOUR
T1 - Solution and solid-state NMR structural studies of antimicrobial peptides LPcin-I and LPcin-II
AU - Park, Tae Joon
AU - Kim, Ji Sun
AU - Ahn, Hee Chul
AU - Kim, Yongae
PY - 2011/9/7
Y1 - 2011/9/7
N2 - Lactophoricin (LPcin-I) is an antimicrobial, amphiphatic, cationic peptide with 23-amino acid residues isolated from bovine milk. Its analogous peptide, LPcin-II, lacks six N-terminal amino acids compared to LPcin-I. Interestingly, LPcin-II does not display any antimicrobial activity, whereas LPcin-I inhibits the growth of both Gram-negative and Gram-positive bacteria without exhibiting any hemolytic activity. Uniformly 15N-labeled LPcin peptides were prepared by the recombinant expression of fusion proteins in Escherichia coli, and their properties were characterized by electrospray ionization mass spectrometry, circular dichroism spectroscopy, and antimicrobial activity tests. To understand the structure-activity relationship of these two peptides, they were studied in model membrane environments by a combination of solution and solid-state NMR spectroscopy. We determined the tertiary structure of LPcin-I and LPcin-II in the presence of dodecylphosphorylcholine micelles by solution NMR spectroscopy. Magnetically aligned unflipped bicelle samples were used to investigate the structure and topology of LPcin-I and LPcin-II by solid-state NMR spectroscopy.
AB - Lactophoricin (LPcin-I) is an antimicrobial, amphiphatic, cationic peptide with 23-amino acid residues isolated from bovine milk. Its analogous peptide, LPcin-II, lacks six N-terminal amino acids compared to LPcin-I. Interestingly, LPcin-II does not display any antimicrobial activity, whereas LPcin-I inhibits the growth of both Gram-negative and Gram-positive bacteria without exhibiting any hemolytic activity. Uniformly 15N-labeled LPcin peptides were prepared by the recombinant expression of fusion proteins in Escherichia coli, and their properties were characterized by electrospray ionization mass spectrometry, circular dichroism spectroscopy, and antimicrobial activity tests. To understand the structure-activity relationship of these two peptides, they were studied in model membrane environments by a combination of solution and solid-state NMR spectroscopy. We determined the tertiary structure of LPcin-I and LPcin-II in the presence of dodecylphosphorylcholine micelles by solution NMR spectroscopy. Magnetically aligned unflipped bicelle samples were used to investigate the structure and topology of LPcin-I and LPcin-II by solid-state NMR spectroscopy.
UR - http://www.scopus.com/inward/record.url?scp=80052509416&partnerID=8YFLogxK
U2 - 10.1016/j.bpj.2011.06.067
DO - 10.1016/j.bpj.2011.06.067
M3 - Article
C2 - 21889457
AN - SCOPUS:80052509416
SN - 0006-3495
VL - 101
SP - 1193
EP - 1201
JO - Biophysical Journal
JF - Biophysical Journal
IS - 5
ER -