11 Jun A wide range of bacterial species are known to localize to tumors
Question
A wide range of bacterial species are known to localize to tumors after intravenous (IV) injection. This occurs for a wide variety of solid tumors, including brain, and breast cancers. These microbes impart their selectivity for tumors by exploiting the hypoxic microenvironment (i.e.,low oxygen concentration), poor immune surveillance, and the increased availability of nutrients. This provides an additional cue that could be exploited to restrict infection to the tumor microenvironment (Figure 1). Using a genetic engineering approach, the capacity of bacteria to invade mammalian cells can be linked with the density of bacteria by placing invasin under the control of a simple hypoxia sensing genetic circuit.
Figure 1:Design for induction- dependent invasion of a cancer cell. Under conditions of low cell-density or normal aerobic growth, engineered bacteria are non-invasive. Above a critical cell density or in a hypoxic environment, sensors are activated resulting in the synthesis of invasin from the bacteriaand the invasion of tumor cells.
a) In a table, demonstrate all the possible input and output of this hypoxia sensing genetic circuit. Assume that low cell density and aerobic condition is considered the same condition, and the high cell density and hypoxia is another condition; in other words, do not consider cell density and oxygen concentration as two different types of inputs(Hint: First of all, define what are 1 and 0 for your different inputs and outputs). (1%)
b) If you are to further improve the specificityof the current genetic circuit to target cancer but not other normal cell types, you are going to add an additional input to the circuit which is necessary to trigger the release of invasin. What type of logic gate will be involved? (0.5%)
c) Drawthe logic gate chosen in 1b) and label the input and output terminals. (2%)
d)Assume that the new input is a cytokine level [Ctumor] secreted specifically by tumor cells, and that the invasin will only be secreted when the bacteria sense both hypoxia and high [Ctumor]. In a table, demonstrate all the possible input and output of this modified 2-input genetic circuit. (Hint: First of all, define what are 1 and 0 for your different inputs and outputs). (2.5%)
Our website has a team of professional writers who can help you write any of your homework. They will write your papers from scratch. We also have a team of editors just to make sure all papers are of HIGH QUALITY & PLAGIARISM FREE. To make an Order you only need to click Ask A Question and we will direct you to our Order Page at WriteDemy. Then fill Our Order Form with all your assignment instructions. Select your deadline and pay for your paper. You will get it few hours before your set deadline.
Fill in all the assignment paper details that are required in the order form with the standard information being the page count, deadline, academic level and type of paper. It is advisable to have this information at hand so that you can quickly fill in the necessary information needed in the form for the essay writer to be immediately assigned to your writing project. Make payment for the custom essay order to enable us to assign a suitable writer to your order. Payments are made through Paypal on a secured billing page. Finally, sit back and relax.
About Writedemy
We are a professional paper writing website. If you have searched a question and bumped into our website just know you are in the right place to get help in your coursework. We offer HIGH QUALITY & PLAGIARISM FREE Papers.
How It Works
To make an Order you only need to click on “Order Now” and we will direct you to our Order Page. Fill Our Order Form with all your assignment instructions. Select your deadline and pay for your paper. You will get it few hours before your set deadline.
Are there Discounts?
All new clients are eligible for 20% off in their first Order. Our payment method is safe and secure.