Tuesday, April 1, 2008

My morning is blown.

I really wish something would just work. My job is a lot like my golf game. I am a lousy golfer but every now and again, I pull off a tremendous shot. That one shot out of 100 (my brothers may remember that 321 yard drive straight down the fairway on the first hole we played right before Adam's wedding) is all it takes to bring me back. Research is a lot like that. Most of the time, we fail but it only takes one good result to keep us going. I've been swinging a lot lately but just haven't connected.

Last night I innoculated three flasks of growth media with bacteria and not one of them grew. This would either indicate that my bacterial stocks have gone bad (unlikely) or that I am using the wrong antibiotic (also unlikely, but I went by memory so I could be wrong). This process is about as basic as washing dishes so not a lot should go wrong. I am going to check my notes to ensure that I used the correct antibiotic.


This particular project has been a real pain in the neck. We got these three DNA constructs (A DNA construct is generally in the form of plasmid or circular DNA. Your gene of interest is inserted into a larger chunk of DNA that contains sequences to enhance the production of your gene of interest such as a promoter and a poly A tail. The plasmid backbone also contains a gene that for antibiotic resistance to assist in the selection of bacterial clones that contain your gene of interest) from another researcher but didn't get much information about them. Generally, when you send someone a plasmid, you also send them a plasmid map and a sequence. We got nothing. I didn't even know what plasmid backbone my gene was in. I had to design some DNA primer so that I could sequence my gene from the inside out so that I could see what the DNA sequence upstream and downstream of my gene was. I then took this data and ran it through a data base at the NIH (a process called BLAST). The results indicated that my gene was in a plasmid called pCDNA 3.1-. pCDNA 3.1- and its family members contain an ampicillin resistance gene. The typical way to store and mass produce this plasmid DNA is to insert it into E. coli bacteria. It is stored at -80 degrees C and when needed, a small stab of frozen bacteria is placed into growth media and incubated overnight with the appropriate antibiotics. Unfortunately, my bacteria didn't grow last night. Back to square one.

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