In this article we will discuss about the structure of lac operon in E. coli. The lac operon comprises three structural genes (z, y & a) and produces a polycistronic mRNA (Lac mRNA). This messenger RNA codes for β-galactosidase, lac permease and transacetylase. The lac permease is a single unit protein that acts as a carrier for the entrance of [...]
In this article we will discuss about some of the important structural features of DNA. 1. DNA exists as a double helix in which the two polynucleotide chains are coiled about one another in a spiral with a diameter of about 20Å (Fig. 1). 2. Concentration of thymine was always equal to the concentration of adenine and the concentration of [...]
In this article we will discuss about:- 1. Definition of Operon 2. Features of Operon 3. Effector Control of Messenger Synthesis 4. Polarity 5. Modulation. Definition of Operon: In 1961 two Nobel laureates, Jacob and Monod, postulated the existence of new genetic unit, the operon to explain the integrated control of the action of genes in a biosynthetic pathway in [...]