What is the Difference Between Prokaryotic and Eukaryotic Topoisomerase?

The main difference between prokaryotic and eukaryotic topoisomerases lies in their cellular origin, distribution, and function. Topoisomerases are enzymes that play a crucial role in the replication, transcription, and recombination of DNA by carrying out DNA-strand passage reactions. Here are the key differences between prokaryotic and eukaryotic topoisomerases:

1. Cellular Origin: Prokaryotic topoisomerases are present in the cells of prokaryotic organisms, such as bacteria and archaea, while eukaryotic topoisomerases are found in the cells of eukaryotic organisms, including plants, animals, and fungi.
2. Distribution: Prokaryotic topoisomerases are present in the cytoplasm of the cell, whereas eukaryotic topoisomerases are located in the nucleus.
3. Function: Prokaryotic topoisomerase I (topo IA) can only relax negative supercoiled DNA, whereas eukaryotic topoisomerase I (topo IB) can introduce positive supercoils and relax DNA. Both prokaryotic and eukaryotic topoisomerases can remove both positive and negative supercoils, but they differ in their specific functions.
4. Subtypes: Prokaryotic topoisomerases include type IA, type IC, and reverse gyrase, while eukaryotic topoisomerases include type IA and type IB. Type II prokaryotic topoisomerases include type IIA and type IIB, while type II eukaryotic topoisomerases are the same.

Despite these differences, both prokaryotic and eukaryotic topoisomerases share some similarities:

• They cause single-stranded or double-stranded breaks to relieve stress during DNA replication.
• They are essential for DNA replication.
• Both topoisomerases are inhibited by camptothecin and non-camptothecin drugs.

Comparative Table: Prokaryotic vs Eukaryotic Topoisomerase

The main differences between prokaryotic and eukaryotic topoisomerases are their cellular origin, distribution, and the specific enzymes involved. Here is a table summarizing these differences:

Despite these differences, both prokaryotic and eukaryotic topoisomerases are essential for DNA replication, can remove both positive and negative supercoils, and share similar functions in modulating DNA supercoiling to relieve stress during DNA replication and transcription.