Part:BBa_K3598008

Snake Cathelicidin-BF

Snake Cathelicidin-BF is an antimicrobial peptide purified from the snake venoms of Bungarus fasciatus. It is the first identified cathelicidin antimicrobial peptide in reptiles.

Figure 1. Part demonstration

Experiments and Results

The Snake Cathelicidin-BF coding part is the original sequence of Snake Cathelicidin-BF,which is an excellent antimicrobial pepetide. We verified its antimicrobial potency through two methods: plate inhibition zones assay and OD600 analysis. In plate inhibition zones assay,wo placed pieces of paper soaked with AMP solutions onto plates inoculated with E.coli MG1655 and P.acnes and observing bacteria growth inhibition zones. In OD600 analysis, we added AMP solutions into liquid culture inoculated with the bacteria and measuring OD600 value.

Figure 2. AMPs test methods

Plate verification Results

The plate results showed inhibition zones in areas of direct contact between bacteria and Snake Cathelicidin-BF, which means Snake Cathelicidin-BF is effective in killing both E.coli and P.acnes, while would not affect bacteria outside its contact.

Figure 3. Plate verification result of Snake Cathelicidin-BF's efficiency to E. coli MG1655

Figure 4. Plate verification result of Snake Cathelicidin-BF's efficiency to P. acnes

OD600 Verification

Then, we verified Snake Cathelicidin-BF's ability to kill E. coli MG1655 and P. acnes by adding its solution to liquid medium inoculated with the two bacteria.

We first test the efficiency to E.coli, the AMP concentration gradient as 0, 2, 4, 8, 12, 16 mg/L as a group, 0, 0.5, 1, 2, 3 mg/L as a group, and measured the OD600 of cells through time. In the results (Figure.5), we can observe that the cell growth was severely affected by Snake Cathelicidin-BF, E. coli almost stop growing when the Snake cathelicidin-BF solution reached a concentration of 4 mg/L. In low concentration, Snake cathelicidin-BF just affect the growth rate of E.coli, the Final OD600 were almost same with control. While in high concentration, both growth rate and final OD600 were sharp dropped.

Figure 5. OD600 verification of Snake Cathelicidin-BF's efficiency to E. coli

Since P. acnes grow slowly, so we only measured OD600 after 48 hours of cultivation with different Snake cathelicidin-BF concentration. The results indicate that Snake Cathelicidin-BF's ability to kill P. acnes peaked at concentration 16mg/L, its effect reaching OD600 of 0.23, about 13.5% less than the control.

Figure 6. OD600 verification result of Snake Cathelicidin-BF's ability to kill P. acnes

Sequence and Features

Assembly Compatibility:

• 10
  COMPATIBLE WITH RFC[10]
• 12
  COMPATIBLE WITH RFC[12]
• 21
  COMPATIBLE WITH RFC[21]
• 23
  COMPATIBLE WITH RFC[23]
• 25
  COMPATIBLE WITH RFC[25]
• 1000
  COMPATIBLE WITH RFC[1000]