In this article we will discuss about the process of transcription in prokaryotes and eukaryotes. Transcription in Prokaryotes: DNA dependent RNA polymerase is the single enzyme that catalyses the transcription of all types of bacterial RNA. (i) Initiation: RNA polymerase binds to promoter and initiates transcription. It associates transiently with 'initiation factor' (σ) and uses nucleoside triphosphates as substrate, obeying [...]
In this article we will discuss about the genetic code, gene expression and DNA fingerprinting. Genetic Code: Genetic code is the relationship between the sequence of nucleotides on mRNA and the sequence of amino acids in the polypeptide. George Gamow, a physicist proposed that in order to code for all the 20 amino acids, the code should be made up [...]
In this article we will discuss about the packaging of DNA helix in prokaryotes and eukaryotes. Packaging in Prokaryotes: In prokaryotes like E. coli, a well-defined nucleus is absent. So, DNA (carrying negative charge) is held together with some proteins (that have positive charge) in a region known as nucleoid. The DNA in nucleoid is organised in nucleus in large [...]