Tachyplesin: Difference between revisions

Line 1:

== Introduction ==

Tachyplesin 1 (TP-1) is an [http://en.wikipedia.org/wiki/Antimicrobial_peptides antimicrobial polypeptide] originally detected in the leukocytes of Japanese [http://en.wikipedia.org/wiki/Horseshoe_crab Horse Shoe Crab].

Tachyplesin I (TP-I) is an [http://en.wikipedia.org/wiki/Antimicrobial_peptides antimicrobial polypeptide] originally detected in the leukocytes of Japanese [http://en.wikipedia.org/wiki/Horseshoe_crab Horse Shoe Crab]. It has also been reported to inhibit the growth of [http://en.wikipedia.org/wiki/Gram-positive_bacteria gram positive bacteria], [http://en.wikipedia.org/wiki/Fungus fungui] and [http://en.wikipedia.org/wiki/Virus viruses] suggesting its antimicrobial property.

The antimicrobial activity of the peptide is ~~closely~~ related to the composition of the pathogen membrane and ability of the peptide to permeabilize the cell membranes. Bacteria and fungi have negatively charged membranes, and the interaction of <scene name='67/671725/Cationic_peptide_tpi/1'>~~cationic peptides such as~~ TP-1 </scene> is mediated in large part by electrostatic interactions<ref name=Laederach>PMID:12369825</ref> (you can see the {{Template:ColorKey_Hydrophobic}} and {{Template:ColorKey_Polar}} amino acids).

The antimicrobial activity of the peptide is related to the composition of the pathogen membrane and ability of the peptide to permeabilize the cell membranes. Bacteria and fungi have negatively charged membranes, and the interaction of <scene name='67/671725/Cationic_peptide_tpi/1'> TP-I </scene> is mediated in large part by electrostatic interactions<ref name=Laederach>PMID:12369825</ref> (you can see the {{Template:ColorKey_Hydrophobic}} and {{Template:ColorKey_Polar}} amino acids).

Specifically, TP-I shows high affinity for [http://en.wikipedia.org/wiki/Lipopolysaccharide lipopolysaccharides (LPS)] of [http://en.wikipedia.org/wiki/Gram-negative_bacteria gram-negative bacteria], thus neutralizing its effects.

It shows high affinity for [http://en.wikipedia.org/wiki/Lipopolysaccharide lipopolysaccharides (LPS)] of [http://en.wikipedia.org/wiki/Gram-negative_bacteria gram-negative bacteria], thus neutralizing its effects. It has also been reported to inhibit the growth of [http://en.wikipedia.org/wiki/Gram-positive_bacteria gram positive bacteria], [http://en.wikipedia.org/wiki/Fungus fungui] and [http://en.wikipedia.org/wiki/Virus viruses].

== Structural highlights ==

Tachyplesine 1 is a 17-residue peptide containing six cationic residues.

Tachyplesine 1 is a 17-residue peptide containing six cationic residues with molecular weight - 2,269 and isoelectric point(pI) of 9.93. <ref name=Chen>Chen, Yixin, et al. "RGD-Tachyplesin inhibits tumor growth." Cancer research 61.6 (2001): 2434-2438.‏</ref>

~~It's~~ molecular weight is 2,269 and ~~has~~ pI of 9.93. <ref name=Chen>Chen, Yixin, et al. "RGD-Tachyplesin inhibits tumor growth." Cancer research 61.6 (2001): 2434-2438.‏</ref>

The amino acid sequence of the TP-1 is NH₂-Lys-Trp-Cys-Phe-Arg-Val-Cys-Tyr-Arg-Gly-Ile-Cys-Tyr-Arg-Arg-Cys-Arg-CONH₂.

~~It adopts~~ antiparallel β-sheet (hairpin) conformation in solution stabilized by two cross-strand <scene name='67/671725/Disulfide_bonds/1'> disulfide bonds </scene> between Cys³-Cys¹⁶ and Cys⁷-Cys¹², and its [http://en.wikipedia.org/wiki/Protein_primary_structure C-terminus is amidated].<ref name=Laederach>PMID:12369825</ref><ref name=Kushibiki>PMID:24389234</ref>

The sequence adapts antiparallel β-sheet (hairpin) conformation in solution stabilized by two cross-strand <scene name='67/671725/Disulfide_bonds/1'> disulfide bonds </scene> between Cys³-Cys¹⁶ and Cys⁷-Cys¹², and its [http://en.wikipedia.org/wiki/Protein_primary_structure C-terminus is amidated].<ref name=Laederach>PMID:12369825</ref><ref name=Kushibiki>PMID:24389234</ref>. Besides, there exists H-bond and aromatic ring stacking interactions which helps stabilizing the hairpin loop structure of the peptide.

The β-hairpin structure is well characterized by a β-turn for the gentrally located residues Tyr-Arg-Gly-Ile.<ref name=Saravanan>PMID:22464970</ref>

[[Image:scheme.jpg|150px|left|thumb|<b>Figure 1: Drown simplefied tachyplesin I.</b>]]

Tachyplesin 1 is highly stable at low pH and high temperature. This stability seems to be due to the rigid structure imposed by the two disulfid linkage.<ref name=Nakamura>Nakamura, Takanori, et al. "Tachyplesin, a class of antimicrobial peptide from the hemocytes of the horseshoe crab (Tachypleus tridentatus). Isolation and chemical structure." Journal of Biological Chemistry 263.32 (1988): 16709-16713</ref>

~~Besides, there exists H-bond and aromatic ring stacking interactions which helps stabilizing the hairpin loop structure of the peptide.~~

Along with TP-1, there exists three linear derivatives: <scene name='67/671725/1ma4/3'>TPY4</scene>, TPF4 and TPA4 as shown below.

Tachyplesin: Difference between revisions

Navigation menu

Page actions

Page actions

Personal tools

Navigation

Search

Tools

@@ Line 1: / Line 1: @@
 == Introduction ==
 <StructureSection load='1MA2' size='340' side='right' caption='1MA2' scene='67/671725/First_scene/1'>
-Tachyplesin 1 (TP-1) is an [http://en.wikipedia.org/wiki/Antimicrobial_peptides antimicrobial polypeptide] originally detected in the leukocytes of Japanese [http://en.wikipedia.org/wiki/Horseshoe_crab Horse Shoe Crab].
+Tachyplesin I (TP-I) is an [http://en.wikipedia.org/wiki/Antimicrobial_peptides antimicrobial polypeptide] originally detected in the leukocytes of Japanese [http://en.wikipedia.org/wiki/Horseshoe_crab Horse Shoe Crab]. It has also been reported to inhibit the growth  of [http://en.wikipedia.org/wiki/Gram-positive_bacteria gram positive bacteria], [http://en.wikipedia.org/wiki/Fungus fungui] and [http://en.wikipedia.org/wiki/Virus viruses] suggesting its antimicrobial property.
-The antimicrobial activity of the peptide is closely related to the composition of the pathogen membrane and ability of the peptide to permeabilize the cell membranes. Bacteria and fungi have negatively charged membranes, and the interaction of <scene name='67/671725/Cationic_peptide_tpi/1'>cationic peptides such as TP-1 </scene> is mediated in large part by electrostatic interactions<ref name=Laederach>PMID:12369825</ref> (you can see the {{Template:ColorKey_Hydrophobic}} and {{Template:ColorKey_Polar}} amino acids).
+The antimicrobial activity of the peptide is related to the composition of the pathogen membrane and ability of the peptide to permeabilize the cell membranes. Bacteria and fungi have negatively charged membranes, and the interaction of <scene name='67/671725/Cationic_peptide_tpi/1'> TP-I </scene> is mediated in large part by electrostatic interactions<ref name=Laederach>PMID:12369825</ref> (you can see the {{Template:ColorKey_Hydrophobic}} and {{Template:ColorKey_Polar}} amino acids).
+Specifically, TP-I shows high affinity for [http://en.wikipedia.org/wiki/Lipopolysaccharide lipopolysaccharides (LPS)] of [http://en.wikipedia.org/wiki/Gram-negative_bacteria gram-negative bacteria], thus neutralizing its effects.
-It shows high affinity for [http://en.wikipedia.org/wiki/Lipopolysaccharide lipopolysaccharides (LPS)] of [http://en.wikipedia.org/wiki/Gram-negative_bacteria gram-negative bacteria], thus neutralizing its effects. It has also been reported to inhibit the growth  of [http://en.wikipedia.org/wiki/Gram-positive_bacteria gram positive bacteria], [http://en.wikipedia.org/wiki/Fungus fungui] and [http://en.wikipedia.org/wiki/Virus viruses].
 == Structural highlights ==
-Tachyplesine 1 is a 17-residue peptide containing six cationic residues.
+Tachyplesine 1 is a 17-residue peptide containing six cationic residues with molecular weight - 2,269 and isoelectric point(pI) of 9.93. <ref name=Chen>Chen, Yixin, et al. "RGD-Tachyplesin inhibits tumor growth." Cancer research 61.6 (2001): 2434-2438.‏</ref>
-It's molecular weight is 2,269 and has pI of 9.93. <ref name=Chen>Chen, Yixin, et al. "RGD-Tachyplesin inhibits tumor growth." Cancer research 61.6 (2001): 2434-2438.‏</ref>
 The amino acid sequence of the TP-1 is NH₂-Lys-Trp-Cys-Phe-Arg-Val-Cys-Tyr-Arg-Gly-Ile-Cys-Tyr-Arg-Arg-Cys-Arg-CONH₂.
-It adopts antiparallel β-sheet (hairpin) conformation in solution stabilized by two cross-strand <scene name='67/671725/Disulfide_bonds/1'> disulfide bonds </scene>  between Cys³-Cys¹⁶ and Cys⁷-Cys¹², and its [http://en.wikipedia.org/wiki/Protein_primary_structure C-terminus is amidated].<ref name=Laederach>PMID:12369825</ref><ref name=Kushibiki>PMID:24389234</ref>
+The sequence adapts antiparallel β-sheet (hairpin) conformation in solution stabilized by two cross-strand <scene name='67/671725/Disulfide_bonds/1'> disulfide bonds </scene>  between Cys³-Cys¹⁶ and Cys⁷-Cys¹², and its [http://en.wikipedia.org/wiki/Protein_primary_structure C-terminus is amidated].<ref name=Laederach>PMID:12369825</ref><ref name=Kushibiki>PMID:24389234</ref>. Besides, there exists H-bond and aromatic ring stacking interactions which helps stabilizing the hairpin loop structure of the peptide.
 The β-hairpin structure is well characterized by a β-turn for the gentrally located residues Tyr-Arg-Gly-Ile.<ref name=Saravanan>PMID:22464970</ref>
 [[Image:scheme.jpg|150px|left|thumb|<b>Figure 1: Drown simplefied tachyplesin I.</b>]]
 Tachyplesin 1 is highly stable at low pH and high temperature. This stability seems to be due to the rigid structure imposed by the two disulfid linkage.<ref name=Nakamura>Nakamura, Takanori, et al. "Tachyplesin, a class of antimicrobial peptide from the hemocytes of the horseshoe crab (Tachypleus tridentatus). Isolation and chemical structure." Journal of Biological Chemistry 263.32 (1988): 16709-16713</ref>
-Besides, there exists H-bond and aromatic ring stacking interactions which helps stabilizing the hairpin loop structure of the peptide.
 Along with TP-1, there exists three linear derivatives: <scene name='67/671725/1ma4/3'>TPY4</scene>, TPF4 and TPA4 as shown below.