Yeast episomal plasmids (YEps) are shuttle vectors. They can replicate in E. coli and also in yeast. The yeast episomal plasmids and has the following parts: 1. The 2 Micron (µm) Plasmid, 2. LEU2 Gene, and 3. The pBR 322. Part # 1. The 2 Micron (µm) Plasmid: This plasmid is found in several strains of yeast, Saccharomyces cerevisiae. It [...]
Two types of vectors are used for the introduction of foreign genes into plant cells. Among them, the Ti-plasmid of Agrobacterium tumefaciens and a few plant viruses such as caulimoviruses and geminiviruses are the most important ones. Vector # 1. Agrobacterium Tumefaciens Ti Plasmids: Plants cells do not contain natural plasmids that can be utilised as cloning vectors. However, the [...]
The cloning of single genes is usually best carried out using plasmids, since the insert will rarely be larger than about 2 kb. However, for cloning of larger pieces of DNA (e.g., during gene library construction) these plasmids are not suitable as larger inserts increase the plasmid size, making the transformation inefficient. Large DNA molecules can be injected in host [...]