Difference between revisions of "Part:BBa K2609001"
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<h2>Characterization</h2> | <h2>Characterization</h2> | ||
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<h3>Expression and characterization</h3> | <h3>Expression and characterization</h3> | ||
<p>The part was transformed into <I>E.coli</I> BL21(DE3). We ran an SDS-PAGE of the cell lysate of the transformed clones against the protein ladder.The protein has a size~18.7 kDa. However due to the presence of <I>E.coli</I> proteins of similar size, there is no significant difference seen in the two lanes<sup>[2]</sup>. We characterized the protein by checking for its lytic activity as mentioned below.</p> | <p>The part was transformed into <I>E.coli</I> BL21(DE3). We ran an SDS-PAGE of the cell lysate of the transformed clones against the protein ladder.The protein has a size~18.7 kDa. However due to the presence of <I>E.coli</I> proteins of similar size, there is no significant difference seen in the two lanes<sup>[2]</sup>. We characterized the protein by checking for its lytic activity as mentioned below.</p> | ||
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<h3>Characterisation of lytic activity of Endolysin </h3> | <h3>Characterisation of lytic activity of Endolysin </h3> | ||
| − | + | <img src="https://static.igem.org/mediawiki/parts/a/a2/Lytic_Activity_Characterisation_of_Endolysin_iGEM18_IISc_Bangalore.jpg" width=50% style="border: 1px solid black;" align="right"> | |
<p>The lytic activity of endolysin was characterised by measuring the decrease in the optical density of B.cereus cell suspension after addition of endolysin<sup>[2][3]</sup>. Exponentially growing Bacillus cereus cells were washed twice and resuspended in 0.2mM Tris-HCl(pH-8) to adjust to OD<sub>600nm</sub>= 0.6-0.8. Then Endolysin protein(100 µL) was added to 900µL of cell suspension. The following were used as controls:<br> | <p>The lytic activity of endolysin was characterised by measuring the decrease in the optical density of B.cereus cell suspension after addition of endolysin<sup>[2][3]</sup>. Exponentially growing Bacillus cereus cells were washed twice and resuspended in 0.2mM Tris-HCl(pH-8) to adjust to OD<sub>600nm</sub>= 0.6-0.8. Then Endolysin protein(100 µL) was added to 900µL of cell suspension. The following were used as controls:<br> | ||
1. 900µL cell suspension with 100µL of resuspension buffer.<br> | 1. 900µL cell suspension with 100µL of resuspension buffer.<br> | ||
Revision as of 17:53, 8 October 2018
T4 endolysin
The Endolysin(e) gene from the T4 bacteriophage. Works as a lysozyme and degrades the peptidoglycan cell wall. Extracellularly bactericidal for gram-positive bacteria.
Usage and Biology
Biology
The T4 Bacteriophage uses the holin-endolysin system for host lysis. Holins trigger and control the host cell wall degradation at the end of the lytic cycle. Holins create pores in the inner membrane allowing the lysozyme(i.e.,Endolysin) to reach the peptidoglycan region from the cytosol[1].
Usage
We used the sequence with the constitutive promoter(BBa_J23106) for screening of recombinanats after Lambda Red recombination with BBa_K2609017
Characterization
Expression and characterization
The part was transformed into E.coli BL21(DE3). We ran an SDS-PAGE of the cell lysate of the transformed clones against the protein ladder.The protein has a size~18.7 kDa. However due to the presence of E.coli proteins of similar size, there is no significant difference seen in the two lanes[2]. We characterized the protein by checking for its lytic activity as mentioned below.
Characterisation of lytic activity of Endolysin
The lytic activity of endolysin was characterised by measuring the decrease in the optical density of B.cereus cell suspension after addition of endolysin[2][3]. Exponentially growing Bacillus cereus cells were washed twice and resuspended in 0.2mM Tris-HCl(pH-8) to adjust to OD600nm= 0.6-0.8. Then Endolysin protein(100 µL) was added to 900µL of cell suspension. The following were used as controls:
1. 900µL cell suspension with 100µL of resuspension buffer.
2. 900µL cell suspension with 100µL of Lysis Buffer used in protein extraction.
3. 900µL cell suspension wiht 100µL of Proteins from Wild Type E.coli(BL21(DE3))
The OD600nm at 37o was measured using a plate reader at regular intervals of time and the lytic activity was noted from the Change in OD v/s time curve as in Figure 2.
Addition of Endolysin has a much stronger lytic activity compared to the buffer alone. The higher activity of endolysin than the proteins extracted from the wild type led us to the conclusion that the lytic activity is conferred due to the Endolysin plasmid inserted.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25INCOMPATIBLE WITH RFC[25]Illegal AgeI site found at 255
Illegal AgeI site found at 325 - 1000COMPATIBLE WITH RFC[1000]
References
[1]Eric S. Miller, Elizabeth Kutter,et al."Bacteriophage T4 Genome". Microbiol. Mol. Biol. Rev. Mar 2003, 67 (1) 86-156; DOI: 10.1128/MMBR.67.1.86-156.2003<br
[2]Lim, Jeong-A YangᆞSoon-Ryun et al. “Exogenous lytic activity of SPN9CC endolysin against gram-negative bacteria.” Journal of microbiology and biotechnology 24 6 (2014): 803-11.
[3]Jaeeun Park, Jiae Yun, et al. "Characterization of an endolysin, LysBPS13, from a Bacillus cereus bacteriophage", FEMS Microbiology Letters, Volume 332, Issue 1, 1 July 2012, Pages 76–83, https://doi.org/10.1111/j.1574-6968.2012.02578.x
[4]Lim, Jeong-A, et al. "Characterization of Endolysin From a Salmonella Typhimurium-infecting Bacteriophage Spn1s." Research in microbiology 163.3 (2012): 233-241. doi: 10.1016/j.resmic.2012.01.002