Lactoferricin H [id=LFH0009]

Synonym: LFcin H ; LF f(1-47) ; Lfcin H ; LF ((1-11)-(12-47)) (S-S (10-46) and S-S(20-37))

Producer Organism : Native Protein : Production Method :
Human Lactoferrin (LF) Enzymatic hydrolysis and Purification with LC method
Activity : Antibacterial
Target Organisms :

Gram-positive: Kocuria rosea ATCC 186 (MIC=1 然), Staphylococcus aureus (MIC=23 然), Staphylococcus haemolyticus (MIC=50 然), Streptococcus mitis (MIC=50 然).

Gram-negative: Escherichia coli O111 (MIC=18 然), Escherichia coli ML-35 (MIC=25 然), Pseudomonas aeruginosa (MIC=25 然).

NOTE: No activity against Morganella morganii, Salmonella typhimurium (>50 然) .

Description :
Production method: Pepsin hydrolysis and purification with LC method.

The purified peptides, LFH0009 and LFB0084, were about 2-fold and 12-fold more effective than the corresponding undigested lactoferrin, and lactoferricin B was about 9-fold more effective than lactoferricin H. The antibacterial properties of the synthetic peptides (LFH0024 and LFB0089) further confirm that the disulfide bond responsible for the looped structure of the identified domain is not essential for activity (Citation: 1).
Length : 48 Mass (Da): 5 546.16 Common Amino Acids : R
Isolectric Point : 11.78 Net Charge : 9 Absent Amino Acids : HLY
Basic Residues : 11 Acidic Residues : 2 Hydrophobic Residues : 12
Polar Residues : 12 Boman Index : -150.52 Hydropathy Index : -0.833
Aliphatic Index : 52.71 Instability Index : 0 Extinction Coefficient : 11250
Absorbance 280nm : 239.36

Wheel representation

Hydrophobicity plot

Red solid plot : values according to the hydrophobicity scale of Kyte and Doolittle (reference paper).
Yellow dashed plot : Experimentally determined hydrophobicity scale for proteins at membrane interfaces(reference paper).
Green dotted-dashed plot : prediction of transmembrane helices (reference paper). In this scale (unlike the others), more negative values reflect greater hydrophobicity.

Multiple Sequence Alignment (MSA)

 2 LFH0016  100.0%  -----------------TKCFQWQRN----------------------- 
 3 LFH0020   88.9%  -----------------TKCFQWQGN----------------------- 
 4 LFH0017   88.9%  -----------------TKCGQWQRN----------------------- 
 5 LFH0018   77.8%  -----------------TKCFGWGRN----------------------- 
 6 LFH0019   88.9%  -----------------TGCFQWQRN----------------------- 
 7 LFH0011  100.0%  -------------QPEATKCFQWQRNMRKVR------------------ 
 8 LFH0012  100.0%  --------------PEATKCFQWQRNMRKVR------------------ 
 9 LFH0013  100.0%  ---------------EATKCFQWQRNMRKVR------------------ 
10 LFH0014  100.0%  ----------------ATKCFQWQRNMRKVR------------------ 
11 LFH0041   91.7%  -------------------CFQWQRNMRKVA------------------ 
12 LFH0043  100.0%  --------------------FQWQRNMRK-------------------- 
13 LFH0040   91.7%  -------------------CFQWQRNMRKAR------------------ 
14 LFH0015  100.0%  -----------------TKCFQWQRNMRKVR------------------ 
15 LFH0038   91.7%  -------------------CFQWQRNMAKVR------------------ 
16 LFH0039   91.7%  -------------------CFQWQRNMRAVR------------------ 
17 LFH0021  100.0%  -----------------TKCFQWQRNMRKVR------------------ 
18 LFH0027  100.0%  ------------------KCFQWQRNMRKVR------------------ 
19 LFH0030   91.7%  -------------------AFQWQRNMRKVR------------------ 
20 LFH0044  100.0%  --------------------FQWQRNMRKV------------------- 
21 LFH0049  100.0%  --------------------FQWQRNMRKVR------------------ 
22 LFH0045  100.0%  --------------------FQWQRNMRKVR------------------ 
23 LFH0031   91.7%  -------------------CAQWQRNMRKVR------------------ 
24 LFH0055  100.0%  ---------------------QWQRNMRKVR------------------ 
25 LFH0022  100.0%  -----------------TKCFQWQRNMRKVRG----------------- 
26 LFH0029  100.0%  -------------------CFQWQRNMRKVR------------------ 
27 LFH0033   91.7%  -------------------CFQAQRNMRKVR------------------ 
28 LFH0056  100.0%  ------------------------RNMRKVR------------------ 
29 LFH0032   91.7%  -------------------CFAWQRNMRKVR------------------ 
30 LFH0034   91.7%  -------------------CFQWARNMRKVR------------------ 
31 LFH0023   93.3%  -----------------TKCFQWQWNMRKVRG----------------- 
32 LFH0057  100.0%  ---------------------------RKVR------------------ 
33 LFH0035   91.7%  -------------------CFQWQANMRKVR------------------ 
34 LFH0036   91.7%  -------------------CFQWQRAMRKVR------------------ 
35 LFH0046   90.9%  --------------------FQWQRNIRKVR------------------ 
36 LFH0047   90.9%  --------------------FQWQRNIRKVR------------------ 
37 LFH0048   90.9%  --------------------FQWQRNPRKVR------------------ 
38 LFH0037   91.7%  -------------------CFQWQRNARKVR------------------ 
39 LFH0024  100.0%  -----------------TKCFQWQRNMRKVRGPPVSCIKR--------- 
40 LFH0026  100.0%  -----------------TKCFQWQRNMRKVRGPPVSCIKRDS------- 
41 LFH0025  100.0%  -----------------TKCFQWQRNMRKVRGPPVSCIKRDS------- 
42 LFH0042  100.0%  -------------------CFQWQRNMRKVRGPPVSCI----------- 
43 LFH0054  100.0%  --------------------FQWQRNMRKVRGPPVS------------- 
44 LFH0028  100.0%  ------------------KCFQWQRNMRKVRGPPVSCI----------- 
46 LFH0058  100.0%  ---------------------------RKVRGPPVSCIKRDSP------ 
47 LFH0059  100.0%  ------------------------------------CIKRDSP------ 
48 LFH0009A 100.0%  GRRRRSVQWCA-------------------------------------- 
51 LFH0004  100.0%  GRRRRSVQWCA-------------------------------------- 
52 LFH0003  100.0%  GRRRRSVQW---------------------------------------- 
53 LFH0002  100.0%  GRRRRS------------------------------------------- 

Citation: 1

Identification of the bactericidal domain of lactoferrin

Cited Entries: LFH0009, LFH0024, LFB0084, LFB0089

Authors:Bellamy, W., Takase, M., Yamauchi, K., Wakabayashi, H., Kawase, K., Tomita, M.
Journal: Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology 1992, 1121(1-2).
CrossRef External Link
Abstract: We report the existence of a previously unknown antimicrobial domain near the N-terminus of lactoferrin in a region distinct from its iron-binding sites. A single active peptide representing this domain was isolated following gastric pepsin cleavage of human lactoferrin, and bovine lactoferrin, and sequenced by automated Edman degradation. The antimicrobial sequence was found to consist mainly of a loop of 18 amino acid residues formed by a disulfide bond between cysteine residues 20 and 37 of human lactoferrin, or 19 and 36 of bovine lactoferrin. Synthetic analogs of this region similarly exhibited potent antibacterial properties. The active peptide of bovine lactoferrin was more potent than that of human lactoferrin having effectiveness against various Gram-negative and Gram-positive bacteria at concentrations between 0.3 μM and 3.0 μM, depending on the target strain. The effect of the isolated domain was lethal causing a rapid loss of colony-forming capability. Our studies suggest this domain is the structural region responsible for the bactericidal properties of lactoferrin.
Keywords: Lactoferrin; Bactericidal domain; antimicrobial peptide; Lactoferricin
Citation: 2

Potassium efflux induced by a new lactoferrin-derived peptide mimicking the effect of native human lactoferrin on the bacterial cytoplasmic membrane

Cited Entries: LFH0009, LFH0024, LFH0060

Authors:Viejo-Diaz, M., Andres, M.T., Perez-Gil, J., Sanchez, M., Fierro, J.F.
Journal: Biochemistry (Moscow) 2003, 68(2).
CrossRef External Link
Abstract: A 31-amino acid synthetic peptide (NH2-FFSASCVPGADKGQFPNLCRLCAGTGENKCA-COOH) was chemically synthesized based on the amino acid sequence of a region of human lactoferrin homologous to other sequences present in the N- and C-lobes of all members of the transferrin family proteins. The peptide, termed kaliocin-1, and lactoferrin showed a bactericidal effect in assays performed in low-ionic-strength conditions. This is the first time that it is shown that the antimicrobial effect of lactoferrin depends on the extracellular cation concentration. The antimicrobial effect of kaliocin-1 was lower than that of human lactoferrin, but their activities were inhibited by Na+ or K+ in a cation concentration-dependent manner. In addition, the peptide was able to mimic native lactoferrin, inducing K+-efflux and a selective dissipation of the transmembrane electrical potential of Escherichia coli cells without causing extensive damage to the outer and inner bacterial membranes. In contrast, the peptide, but not lactoferrin, was able to permeabilize different ions through liposomal membranes. The hypothetical interaction of kaliocin-1 with a bacterial membrane compound is discussed based in the different ion flux induced on cellular and artificial membranes as well as data from circular dichroism assays. Kaliocin-1 was not cytotoxic and could be a suitable model for the design of analogs able to mimic the antibacterial effect of human lactoferrin.
Keywords: antimicrobial peptide - lactoferrin-derived peptide - lactoferrin - transferrin - lactoferricin - kaliocin - electrical potential - membrane permeabilization

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