What is the Difference Between Serine and Tyrosine Recombinase?

Serine and tyrosine recombinases are two types of enzymes that play a crucial role in site-specific recombination, a process of DNA breakage and reunion that requires no DNA synthesis or high-energy cofactor. They belong to different families based on the nucleophilic amino acid residue they use to attack DNA during site-specific recombination:

• Serine Recombinases: In serine recombinase, serine is the nucleophilic amino acid used by the enzyme to attack DNA during site-specific recombination. Serine recombinases are highly modular, as shown by biochemical studies and crystallographic structures. They are generally encountered in prokaryotes and their viruses, such as eubacteria, archaea, and temperate bacteriophages.
• Tyrosine Recombinases: In tyrosine recombinase, tyrosine is the nucleophilic amino acid used by the enzyme to attack DNA during site-specific recombination. Tyrosine recombinases break and rejoin single strands in pairs to form a Holliday junction intermediate.

The key difference between serine and tyrosine recombinases lies in the amino acid they use to attack DNA during site-specific recombination. While serine recombinases cut all strands in advance of strand exchange and religation, tyrosine recombinases break and rejoin single strands in pairs to form a Holliday junction intermediate.

Comparative Table: Serine vs Tyrosine Recombinase

Here is a table comparing the differences between serine and tyrosine recombinase:

Both serine and tyrosine recombinases are involved in site-specific recombination, which is a type of genetic recombination where DNA strands exchange information. The primary difference between the two is the type of bond they form with DNA: serine recombinases form a phosphoserine bond, while tyrosine recombinases form a phosphotyrosine bond.