The key difference between T4 DNA ligase and E. coli DNA ligase is that T4 DNA ligase is an enzyme that is isolated from bacteriophage T4 while E. coli DNA ligase is an enzyme that is isolated from the bacterium E. coli.
DNA ligase is a specific type of enzyme that facilitates the joining of DNA strands together through the formation of a phosphodiester bond. It plays an important role by repairing single-strand breaks and double-strand breaks in the DNA of living organisms. Moreover, DNA ligase is used in both DNA repair and DNA replication. Apart from the above uses, DNA ligase also has extensive use in molecular biology experiments such as recombinant DNA technology. T4 DNA ligase and E. coli DNA ligase are two types of DNA ligase enzymes.
CONTENTS
1. Overview and Key Difference
2. What is T4 DNA Ligase
3. What is E Coli DNA Ligase
4. Similarities – T4 DNA Ligase and E Coli DNA Ligase
5. T4 DNA Ligase vs E Coli DNA Ligase in Tabular Form
6. Summary – T4 DNA Ligase vs E Coli DNA Ligase
What is T4 DNA Ligase?
T4 ligase is a DNA joining enzyme that is isolated from bacteriophage T4. T4 bacteriophage is a virus that infects Escherichia coli. T4 ligase enzyme is the most commonly used DNA ligase in molecular biological laboratory research. Normally, T4 ligase catalyzes the joining of two cohesive or blunt-ended strands of double-strand DNA between the 5’ phosphate and 3’ hydroxyl groups of adjacent nucleotides. It can also catalyze the joining of RNA to either a DNA or RNA strand in a duplex molecule. However, this enzyme will not join single-stranded nucleic acids. Moreover, it can also ligate blunt-ended DNA with much greater efficiency than E. coli DNA ligase.
Figure 01: T4 DNA Ligase
This enzyme requires ATP as a cofactor. Some genetic engineering research experiments have already produced more active DNA ligase enzymes than wild-type T4 DNA ligase. In one of the approaches, they created a fusion enzyme molecule by combing T4 DNA ligase to either p50 or NF-kB molecule. This new T4 ligase enzyme was 160% more active in blunt-end ligations for cloning purposes than wild-type T4 DNA ligase. Furthermore, the optimal temperature for T4 DNA ligase to catalyze the ligation reaction more precisely is 16 °C.
What is E Coli DNA Ligase?
E. coli DNA ligase is an enzyme that is isolated from E. coli bacteria. The gene responsible for making E. coli DNA ligase is lig gene. The E. coli DNA, ligase as well as most prokaryotes DNA ligases, use energy that is gained by NAD (nicotinamide adenine dinucleotide) to create the phosphodiester bond.
Figure 02: E. Coli DNA Ligase
E. coli DNA ligase is a ligation enzyme that can join DNA fragments by catalyzing the formation of phosphodiester bonds between double-stranded DNA fragments containing 5’ phosphate termini and 3’ hydroxyl termini. Moreover, it does not ligate blunt-ended DNA except under special conditions such as molecular crowding with polyethylene glycol. It also cannot join RNA to DNA efficiently. Furthermore, the activity of E. coli DNA ligase can be enhanced by the presence of DNA polymerase 1 at the right concentration. However, when the concentration of DNA polymerase 1 enzyme is higher, it has adverse effects on E. coli DNA ligase activity.
What are the Similarities Between T4 DNA Ligase and E Coli DNA Ligase?
- T4 DNA ligase and E-coli DNA ligase are two types of DNA ligase enzymes.
- Both are proteins made up of amino acids.
- These enzymes catalyze the formation of a phosphodiester bond between juxtaposed 5’ phosphate and 3’ hydroxyl termini in duplex DNA.
- They have extensive uses in molecular biology experiments such as recombinant DNA technology.
What is the Difference Between T4 DNA Ligase and E Coli DNA Ligase?
T4 DNA ligase is an enzyme that is isolated from bacteriophage T4 while E. coli DNA ligase is an enzyme that is isolated from E. coli bacteria. Thus, this is the key difference between T4 DNA ligase and E. coli DNA ligase. Furthermore, the source of energy for T4 DNA ligase is ATP. On the other hand, the source of energy for E. coli DNA ligase is NAD.
The below infographic presents the differences between T4 DNA ligase and E coli DNA ligase in tabular form for side by side comparison.
Summary – T4 DNA Ligase vs E Coli DNA Ligase
T4 DNA ligase and E. coli DNA ligase are two enzymes that catalyze the formation of a phosphodiester bond between juxtaposed 5’ phosphate and 3’ hydroxyl termini in duplex DNA. T4 ligase is an enzyme that is isolated from bacteriophage T4 while E. coli DNA ligase is an enzyme that is isolated from E. coli bacteria. So, this is the key difference between T4 DNA ligase and E coli DNA ligase.