Line 93: | Line 93: | ||
<figcaption><strong> 2c: Biological functions of LL-37 (Ramos, Domingues, and Gama, 2011)</strong></figcaption> | <figcaption><strong> 2c: Biological functions of LL-37 (Ramos, Domingues, and Gama, 2011)</strong></figcaption> | ||
</figure> | </figure> | ||
+ | </div> | ||
+ | |||
+ | <div class="para"> | ||
+ | <h1>GF-17</h1> | ||
+ | <p style="font-size:20px">GF-17 is a high efficiency anti-microbial peptide which modified from LL-37 residue Phe-17 to Val-32 (Fig 3a). | ||
+ | </p> | ||
+ | </div> | ||
+ | |||
+ | <div class="fig" align="center"> | ||
+ | <figure> | ||
+ | <img width="700px" src="https://static.igem.org/mediawiki/2017/0/01/Peptide_Production_3a.png"> | ||
+ | <figcaption> | ||
+ | <strong>Figure 3a: GF-17 is modified from LL-37. Amino acid residue Gly-16 is modified.</strong> | ||
+ | </figcaption> | ||
+ | </figure> | ||
+ | <figure> | ||
+ | <img width="700px" src="https://static.igem.org/mediawiki/2017/8/83/Peptide_Production_3b.png"> | ||
+ | <figcaption> | ||
+ | <strong>Figure3b: Cartoon view of GF-17 structure (PDB: 2L5M)</strong> | ||
+ | </figcaption> | ||
+ | </figure> | ||
+ | </div> | ||
+ | |||
+ | <div class="para"> | ||
+ | <p style="font-size:20px">Table shows the Minimal Inhibitory concentration (MIC) of Anti-microbial peptides GF-17, GF-18 and their variants. | ||
+ | GF-17 was capable of eliminating both Gram-positive and Gram-negative bacteria, such as S. aureus USA300 | ||
+ | and E. coli K-12 in vitro (Wang et al., 2011). Additionally, to compare with LL-37, GF-17 has highly efficiency | ||
+ | on anti-Staphylococcus aureus biofilm and killing efficiency (Fig 3c, table) ( Mishra et al., 2016; Wang | ||
+ | et al., 2011 ).</p> | ||
+ | </div> | ||
+ | |||
+ | <div class="fig" align="center"> | ||
+ | <figure> | ||
+ | <img width="700px" src="https://static.igem.org/mediawiki/2017/b/bc/Peptide_Production_table.png"> | ||
+ | <figcaption> | ||
+ | <strong>Table: Antimicrobial activity (MIC in μM) of GF-17, GE-18 and their variants (Wang et al., 2011)</figcaption> | ||
+ | </strong> | ||
+ | </figure> | ||
+ | <figure> | ||
+ | <img width="700px" src="https://static.igem.org/mediawiki/2017/d/d5/Peptide_Production_3c.png"> | ||
+ | <figcaption> | ||
+ | <strong>Figure 3c: anti-Staphylococcus aureus Biofilm assay. Two different Staphylococcus aureus strain: USA200 | ||
+ | and USA300. The result shows the GF-17 has more efficiency to anti-Staphylococcus aureus Biofilm.( | ||
+ | Mishra et al., 2016)</strong> | ||
+ | </figcaption> | ||
+ | </figure> | ||
</div> | </div> | ||
</div> | </div> |
Revision as of 09:14, 30 October 2017
Peptide Production
Anti-Microbial Peptide
Anti-microbial peptide (AMP) is a part of the innate immune system of most multi-cellular organisms to counter microbial infections (Margitta and Torsten, 1999). The cationic and amphipathic α-helix structure is the most wildly conformation in those peptides but some hydrophobic α-helical peptides which possess antimicrobial activity. This year we choose three different cationic antimicrobial peptides which encompass α-helical conformation in our project.
Figure 1 shows the molecular mechanism of cationic AMPs α-helical structure. Most of cationic AMPs associate with lipid group of bacteria membrane. The α-helical structure disrupt the packing of lipid molecules such that the membrane becomes leaky (Rocca et al., 1999).
LL-37
LL-37 is the only cathelicidin-derived antimicrobial peptide found in humans (Dürr, Sudheendra and Ramamoorthy, 2006). Mature LL-37 has 37 amino acid residues starting with two leucines (NH2-LLGDFFRKSKEKIGKEFKRIVQRIKDFLRNLVPRTES-COOH). The peptide is cleaved from a larger protein, hCAP-18 by extracellular proteolysis of proteinase 3 from the C-terminal end of hCAP18 (Patricia, 2010; Ramos, Domingues, and Gama, 2011). The peptide composed of two mainly parts: from residue Leu2 to Leu31 is α-helical structure (Fig 2b) and 6 residues form loop structure (Fig 2a).
Ramos, Domingues, and Gama (2011) also reported that LL-37 has additional roles such as regulating the inflammatory response to wound or infection sites, binding and neutralizing LPS, and wound closure apart from anti-microbial property (Figure 2c).
GF-17
GF-17 is a high efficiency anti-microbial peptide which modified from LL-37 residue Phe-17 to Val-32 (Fig 3a).
Table shows the Minimal Inhibitory concentration (MIC) of Anti-microbial peptides GF-17, GF-18 and their variants. GF-17 was capable of eliminating both Gram-positive and Gram-negative bacteria, such as S. aureus USA300 and E. coli K-12 in vitro (Wang et al., 2011). Additionally, to compare with LL-37, GF-17 has highly efficiency on anti-Staphylococcus aureus biofilm and killing efficiency (Fig 3c, table) ( Mishra et al., 2016; Wang et al., 2011 ).