What is the Difference Between B DNA and Z DNA?
🆚 Go to Comparative Table 🆚B-DNA and Z-DNA are two different conformations of DNA helixes. The main differences between them are:
- Helix handedness: B-DNA is a right-handed helix, while Z-DNA is a left-handed helix.
- Repeating unit: In B-DNA, the repeating unit is 1 base pair, while in Z-DNA, the repeating unit is 2 base pairs.
- Helix diameter: B-DNA has a helix diameter of 20 Å, while Z-DNA has a diameter of 18 Å.
- Major and minor grooves: B-DNA has a wide and deep major groove and a narrow and deep minor groove, while Z-DNA has a narrow and deep major groove and a wide and shallow minor groove.
- Number of base pairs per turn: B-DNA has 10.5 base pairs per turn, while Z-DNA has 12 base pairs per turn.
- Distance between adjacent deoxyribonucleotides: In B-DNA, the distance between adjacent deoxyribonucleotides is 0.34 nm, while in Z-DNA, it is 0.37 nm.
- Stability: B-DNA is stable and easy to observe, while Z-DNA is unstable and difficult to observe.
B-DNA is the most common DNA conformation found under normal physiological conditions, while Z-DNA is less common and can be formed under specific conditions, such as high salt concentrations. Z-DNA is believed to play a role in gene expression regulation and genetic recombination.
Comparative Table: B DNA vs Z DNA
There are three major families of DNA helices: A-DNA, B-DNA, and Z-DNA. The helical structure of DNA is variable and depends on the sequence as well as the surrounding environment. Here is a table comparing the differences between B-DNA and Z-DNA:
Parameter | B-DNA | Z-DNA |
---|---|---|
Helix sense | Right-handed | Left-handed |
Base pairs per turn | 10 | 12 |
Axial rise (nm) | 0.34 | 0.45 |
Helix pitch (°) | 34 | 45 |
Base pair tilt (°) | +36 | -30 |
Twist angle (°) | +33 | -30 |
Diameter of helix (nm) | 2.0 | 1.8 |
B-DNA is the most common and widely studied form of DNA, featuring a right-handed double helix with 10 base pairs per turn, an axial rise of 0.34 nm per base pair, and a helix pitch of 34° per base pair. On the other hand, Z-DNA is a left-handed helix with 12 base pairs per turn, an axial rise of 0.45 nm per base pair, and a helix pitch of 45° per base pair. Z-DNA is found in certain regions of the genome, particularly in alternating purine-pyrimidine sequences (e.g., GCGCGC).
- E vs Z Isomers
- Male vs Female DNA
- D Value vs Z Value
- Gene vs DNA
- X vs Y Chromosomes
- ssDNA vs dsDNA
- DNA vs RNA
- rDNA vs cDNA
- DNA vs cDNA
- DNA vs DNAse
- DNA vs Chromosome
- W vs Z Bosons
- Plasmid DNA vs Chromosomal DNA
- Genomic vs Plasmid DNA
- Prokaryotic vs Eukaryotic DNA
- DNA-RNA Hybrids vs dsDNA
- XX vs XY Chromosomes
- B
- Mitochondrial DNA vs Chloroplast DNA