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I need help with my topic!
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deleted-25544
- Posts: 1
- Joined: Sun Oct 11, 2009 8:29 pm
- Occupation: Student: 10th Grade
- Project Question: I can't figure out!
- Project Due Date: mid-January
- Project Status: I am just starting
I need help with my topic!
Last year I went to state science fair competitions with a project about planaria, and I got a second. This year I'm really really pushing to get a first, so I want to pick a great project. I'm more interested in biology than anything and I had a couple ideas... I was very interested in the experiment where you transform E.coli bacteria with a gene that codes for a fluorescent protein, but there doesn't seem to be a lot of variation in what happens with that. Are there any projects/questions that can be made out of this (would seeing if this affected the later growth of the bacteria be good or not)? My teacher also has some fluorescent fungi (Armillariella mellea) that she said I could use if I wanted to. Are there any topics that could be made out of this? Or any interesting and unique things to test the growth of bacteria with? Or any good projects somewhat related to this in general? I really need help, so any input is appreciated!
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aelin
- Former Expert
- Posts: 78
- Joined: Sun Sep 27, 2009 6:50 pm
- Occupation: Student: Junior in College
- Project Question: Role of viral proteins in the HSV1 life cycle, specifically during entry and egress.
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Re: I need help with my topic!
Hi,
Congratulations! Hopefully your project will go well this year as well. I also have done similar work, and there are plenty of ways in which you can take this; really it's all up to you. True, there isn't a ton of variation; many of the overall mechanisms for generating fluorescence are somewhat understood. However, I feel like a lot of this hasn't been done particularly quantitatively, so a lot of it has not been optimized (one thing you could look in to).
The first thing that popped into my mind (and again, you don't have to do this, this i just an idea) involves the lacZ reporter gene. In case you aren't familiar, I'll kind of briefly go over the process (more detail here http://www.bio.davidson.edu/courses/gen ... rters.html). When you transform a plasmid into a bacteria, you want to make sure that your gene of interest is in plasmid, so you can engineer the plasmid with a lacZ site and make a cut site for the gene of interest within that lacZ site. If you successfully insert the gene of interest into the plasmid, it will cut the lacZ gene in half and inactivate it. So, when the plasmid is transformed into the bacteria, some of the bacteria will have the cut lacZ gene (meaning a plasmid with your gene of interest) and some will have a full lacZ gene (a plasmid without your gene of interest). The ones with the lacZ gene will produce beta-galactosidase in the presence of lactose and will catalyze lactose and produce a blue colored colony, whereas the bacteria with the cut lacZ gene (with your gene of interest) will not produce beta-galactosidase and therefore will not cause the colony to be colored blue (it will remain white), allowing you to differentiate between which colonies do and do not have you gene of interest. Now, the process is not 100% accurate since you can get false positives and negatives. I don't believe that this has been very well quantified or optimized, so you do have options in that respect, perhaps trying to modify some initial conditions like length of insert, length of plasmid, strain of bacteria, etc.
Alternately, some of the things that you suggest would work just as well. Extra plasmids and genes would seem to slow growth, but maybe initial growth (or later growth too, who knows?) so you could make a sort of time map of colony counts and sizes (maybe total area?) over time while varying the amount of DNA transformed.
Antibiotic resistance could also be fun to play around with. Maybe you could test the growth rate of satellite colonies or the growth rate of antibiotic resistant versus antibiotic naive bacteria in a non-antibiotic media. All of these sounds really promising; if you have any future questions on a specific direction, be sure to let me know!
Cheers! Hope this helps,
Aaron Lin
Congratulations! Hopefully your project will go well this year as well. I also have done similar work, and there are plenty of ways in which you can take this; really it's all up to you. True, there isn't a ton of variation; many of the overall mechanisms for generating fluorescence are somewhat understood. However, I feel like a lot of this hasn't been done particularly quantitatively, so a lot of it has not been optimized (one thing you could look in to).
The first thing that popped into my mind (and again, you don't have to do this, this i just an idea) involves the lacZ reporter gene. In case you aren't familiar, I'll kind of briefly go over the process (more detail here http://www.bio.davidson.edu/courses/gen ... rters.html). When you transform a plasmid into a bacteria, you want to make sure that your gene of interest is in plasmid, so you can engineer the plasmid with a lacZ site and make a cut site for the gene of interest within that lacZ site. If you successfully insert the gene of interest into the plasmid, it will cut the lacZ gene in half and inactivate it. So, when the plasmid is transformed into the bacteria, some of the bacteria will have the cut lacZ gene (meaning a plasmid with your gene of interest) and some will have a full lacZ gene (a plasmid without your gene of interest). The ones with the lacZ gene will produce beta-galactosidase in the presence of lactose and will catalyze lactose and produce a blue colored colony, whereas the bacteria with the cut lacZ gene (with your gene of interest) will not produce beta-galactosidase and therefore will not cause the colony to be colored blue (it will remain white), allowing you to differentiate between which colonies do and do not have you gene of interest. Now, the process is not 100% accurate since you can get false positives and negatives. I don't believe that this has been very well quantified or optimized, so you do have options in that respect, perhaps trying to modify some initial conditions like length of insert, length of plasmid, strain of bacteria, etc.
Alternately, some of the things that you suggest would work just as well. Extra plasmids and genes would seem to slow growth, but maybe initial growth (or later growth too, who knows?) so you could make a sort of time map of colony counts and sizes (maybe total area?) over time while varying the amount of DNA transformed.
Antibiotic resistance could also be fun to play around with. Maybe you could test the growth rate of satellite colonies or the growth rate of antibiotic resistant versus antibiotic naive bacteria in a non-antibiotic media. All of these sounds really promising; if you have any future questions on a specific direction, be sure to let me know!
Cheers! Hope this helps,
Aaron Lin
Hope this helps!
Aaron Lin
Aaron Lin