Team:Hong Kong-CUHK/Laboratory
From 2011.igem.org
(Difference between revisions)
Line 35: | Line 35: | ||
</p> | </p> | ||
<p> | <p> | ||
- | We are glad to cooperate with HKUST-Hong_Kong | + | We are glad to cooperate with HKUST-Hong_Kong on modeling the hypothetical behavior of bcr gene induced by lac or T7. bcr is amembrane protein that actively pumps out a variety of substrates from the cell,notably antibiotics such as tetracycline and kanamycin. Hence, expression of bcr leads to antibiotic resistance. The collaboration was established because of the similarity between halorhodopsin and bcr. Both proteins are membrane transporters, and we are familiar with such scenario. |
</p> | </p> | ||
<p> | <p> | ||
Line 41: | Line 41: | ||
</p> | </p> | ||
<p> | <p> | ||
- | Minimum Inhibitory Concentration (MIC) is acommonly-used indicator to measure the vulnerability of bacteria in presence | + | Minimum Inhibitory Concentration (MIC) is acommonly-used indicator to measure the vulnerability of bacteria in presence of antibiotics. It is usually determined by the minimum concentration of antibiotics that could cause observable reduction in turbidity and/or optical density for an overnight LB culture. We modeled the relationship between the change of MIC of tetracycline and kanamycin respectively and the concentration of IPTG, which induces bcr downstream of P<sub>lac</sub> in <em>E. coli</em>. The change of MIC is reported as the ratio of the MIC of bcr-transformed <em>E.coli</em> over that of wildtype <em>E. coli</em>. |
</p> | </p> | ||
<p> | <p> | ||
Line 47: | Line 47: | ||
</p> | </p> | ||
<p> | <p> | ||
- | <strong> | + | <strong>Modeling results</strong> |
<table> | <table> | ||
<tr> | <tr> | ||
Line 75: | Line 75: | ||
</p> | </p> | ||
<p> | <p> | ||
- | We modeled HKUST’s data with three assumptions.Firstly, antibiotics are applied during exponential phase or stationary phase.Secondly, P<sub>lac</sub> only affects the expression of target genes (bcr).Finally, IPTG doesn’t affect other metabolic pathways except P<sub>lac</sub>induction. We modeled the activity of P<sub>lac</sub> under different IPTG concentrations(Fig. 1) and the relationship between the activity of native promoter of | + | We modeled HKUST’s data with three assumptions. Firstly, antibiotics are applied during exponential phase or stationary phase. Secondly, P<sub>lac</sub> only affects the expression of target genes (bcr). Finally, IPTG doesn’t affect other metabolic pathways except P<sub>lac</sub> induction. We modeled the activity of P<sub>lac</sub> under different IPTG concentrations(Fig. 1) and the relationship between the activity of native promoter of bcr and the MIC change (Fig. 2). Then we achieved our goal to show the effect of IPTG concentration on the change of MIC by combining the P<sub>lac</sub>activity and the MIC change of wild type bcr (Fig. 3). We discovered that only a small amount of IPTG is essential to induce bcr and trigger similar antibiotic resistance compared with wild type. However, further increase of IPTG concentration has limited effect on strengthening antibiotic resistance.This is probably due to the saturation of IPTG in bcr induction where the bcr amount reaches the peak, while the concentration of antibiotics keeps increasing. |
</p> | </p> | ||
<p> | <p> | ||
Line 87: | Line 87: | ||
</p> | </p> | ||
<p> | <p> | ||
- | http://regulondb.ccg.unam.mx/operon?term=ECK120014773&format=jsp#myReferences | + | <a href="http://regulondb.ccg.unam.mx/operon?term=ECK120014773&format=jsp#myReferences">http://regulondb.ccg.unam.mx/operon?term=ECK120014773&format=jsp#myReferences</a> |
</p> | </p> | ||
<p> | <p> | ||
- | [2] Increased expression of the multidrug | + | [2] Increased expression of the multidrug efflux genes acrAB occurs during slow growth of Escherichia coli FEMS Microbiology Letters Volume 207, Issue 1, pages 91–95, January 2002 |
</p> | </p> | ||
<p> | <p> | ||
- | [3] http://www.expressys.com/main_applications.html | + | [3] <a href="http://www.expressys.com/main_applications.html">http://www.expressys.com/main_applications.html</a> |
</p> | </p> | ||
<p> | <p> | ||
- | [4] http://partsregistry.org/Part:BBa_R0010:Experience | + | [4] <a href="http://partsregistry.org/Part:BBa_R0010:Experience">http://partsregistry.org/Part:BBa_R0010:Experience</a> |
</p> | </p> | ||
<p> | <p> | ||
- | [5] Analysis of a Complete Library of Putative | + | [5] Analysis of a Complete Library of Putative Drug Transporter Genes in Escherichia coli J Bacteriol. 2001 October; 183(20):5803–5812. |
</p> | </p> | ||
<p> | <p> | ||
- | [6] https://2011.igem.org/Team:TU_Munich/lab/results | + | [6] <a href="https://2011.igem.org/Team:TU_Munich/lab/results">https://2011.igem.org/Team:TU_Munich/lab/results</a> |
</p> | </p> | ||
<p> | <p> |
Revision as of 06:41, 5 October 2011