Polyethylene glycol (PEG) is a polyer compound. The compound has varied applications. Its biological uses include being used as a precipitant for plasmid DNA isolation and protein crystallisation. PEG is also used as a fusing agent in transformation experiments. The gene or desired fragment of DNA can be transferred into host cell without use of vector. PEG with calcium ions allows membrane to become charged and allow entry of gene.

Endonucleases are enzymes that cleave phosphodiester bond within a polynucleotide chain. Some, such as deoxyribonuclease I, cut DNA relatively non-specifically, while many, typically called restriction endonucleases or restriction enzymes, cleave only at very specific nucleotide sequences.

The fermentor is a vessel or an apparatus which is used for fermentation activity of microorganisms for commercial production of certain substances. There are different types of fermentors depending on type of product and volume of product to be produced. The common type of fermentors are tower fermenter, bubble column, air-lift, fluid bed fermenter, etc. 

Chimeric DNA is recombinant DNA molecule or hybrid DNA that carries DNA segments from or sources, i.e., it is mix of DNA from two different organisms. Uracil is a pyrimidine base which is present in RNA, not in DNA.