- 1 What is the role of major and minor grooves in DNA?
- 2 Why are major and minor grooves important?
- 3 What is the purpose of the minor groove?
- 4 What does DNA contain the instructions for?
- 5 Why is B form DNA most stable?
- 6 Does a form DNA have major and minor grooves?
- 7 What proteins are associated with DNA?
- 8 Why are the two grooves of B-DNA different widths?
- 9 What is the difference between the major and minor groove?
- 10 Which groove is used most often for DNA protein binding?
- 11 What is minor groove of DNA?
- 12 What are the 3 types of DNA?
- 13 Why is a DNA shorter than B-DNA?
- 14 Why is DNA called an acid?
What is the role of major and minor grooves in DNA?
As you noted, the major groove is wider than the minor groove. These grooves allow proteins to bind to and recognize DNA sequences from the outside of the helix. The grooves expose the edges of each base pair located inside the helix, which allows proteins to chemically recognize specific DNA sequences.
Why are major and minor grooves important?
They arise from the antiparallel arrangement of the two backbone strands. Note that the grooves are actual structural features of the molecule, not consequences of the way it is drawn. The grooves are important in the attachment of DNA Binding Proteins involved in replication and trascription.
What is the purpose of the minor groove?
The minor groove of A-tract DNA provides a unique chemical environment. The polarity and electronegative potential are high. The floor and walls of the groove are lined with hydrogen bond acceptors but are devoid of hydrogen bond donors.
What does DNA contain the instructions for?
DNA contains the instructions needed for an organism to develop, survive and reproduce. To carry out these functions, DNA sequences must be converted into messages that can be used to produce proteins, which are the complex molecules that do most of the work in our bodies.
Why is B form DNA most stable?
It is known that the stability of the double helical structure of B – DNA is supplied by the hydrogen bonds as proposed by Watson and Crick3 and by the stacking interactions.
Does a form DNA have major and minor grooves?
Structure. A- DNA is fairly similar to B- DNA given that it is a right-handed double helix with major and minor grooves. The major groove of A- DNA is deep and narrow, while the minor groove is wide and shallow.
What proteins are associated with DNA?
DNA -binding proteins include transcription factors which modulate the process of transcription, various polymerases, nucleases which cleave DNA molecules, and histones which are involved in chromosome packaging and transcription in the cell nucleus.
Why are the two grooves of B-DNA different widths?
The double helix structure of DNA contains a major groove and minor groove. In B – DNA the major groove is wider than the minor groove. Given the difference in widths of the major groove and minor groove, many proteins which bind to B – DNA do so through the wider major groove.
What is the difference between the major and minor groove?
The strand backbones are closer together on one side of the helix than on the other. The major groove occurs where the backbones are far apart, the minor groove occurs where they are close together. The grooves twist around the molecule on opposite sides.
Which groove is used most often for DNA protein binding?
The α-helix is the most frequently used secondary structure element for specific DNA recognition in the major groove. The positioning of the helix in the major groove can vary between different protein families and also among different proteins within the same family, as reviewed previously .
What is minor groove of DNA?
The minor groove contains the pyrimidine O-2 and the purine N-3 of the base pair, and the major groove is on the opposite side of the pair. The methyl group of thymine also lies in the major groove. In B- DNA, the major groove is wider (12 versus 6 Å) and deeper (8.5 versus 7.5 Å) than the minor groove (Figure 27.8).
What are the 3 types of DNA?
There are three different DNA types:
- A-DNA: It is a right-handed double helix similar to the B-DNA form.
- B-DNA: This is the most common DNA conformation and is a right-handed helix.
- Z-DNA: Z-DNA is a left-handed DNA where the double helix winds to the left in a zig-zag pattern.
Why is a DNA shorter than B-DNA?
Ø A DNA is 20 to 25% shorter than B – DNA due to the smaller rise per turn. Ø A- DNA contains 11.6 base pairs per turn. Ø The distance between the adjacent base pairs is 2.9 Å. Ø Individual base pairs in A- DNA are 20⁰ tilted with respect to the helical axis.
Why is DNA called an acid?
DNA or RNA are called nucleic acids because of the acidic nature of the phosphate group attached to them. The phosphodiester bond can easily lose the proton in the presence of nucleophile group subsequently masking the basic nature of nitrogenous bases.