Week 9 - November 11, 2022

Tuesday, November 8, 2022 - Thursday, November 10, 2022 

In the lab, we talked about plasmids and plasmid  extractions and I spent time on my own reading up about what plasmids are. A plasmid is essentially a small circular piece of DNA found in bacterial cells that replicate independently from the host’s chromosomal DNA.  Plasmids can exist naturally in archaea and eukaryotes. For example, they can exist in yeast and plants. There are also plasmids utilized in the lab. These are typically artificial and designed to introduce foreign DNA into another cell. These plasmids have an origin or replication, selection marker, and cloning site. 

The origin of replication is a DNA sequence which allows initiation of replication within a plasmic by recruiting replication machinery proteins. A selection marker is the antibiotic resistance gene which allows for selection in the bacteria. The cloning site is a short segment of DNA which contains many restriction sites. After reading up on them, I learned that plasmids are important for bacterial evolution and adaptation.

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