T4 UvsX recombinase, derived from T4 phage, is a homolog of the RecA/Rad51 family. RecA/Rad51 recombinase family plays an important role in the repair of double-stranded DNA break and the restart of replication forks. T4 UvsX recombinase can anchor on single-stranded DNA together with other recombinase and activate it to scan for homologous sequences on other double-stranded DNA for further strand replacement. The enzyme has no nuclease activity.

T4 UvsY Protein, a phage T4 recombination mediator protein, plays an important role in T4 homologous recombination. During the recombination, T4 UvsX recombinase must compete with the prebound gp32 single-stranded binding protein for DNA-binding sites. T4 UvsY protein stimulates this filament nucleation event, promoting the combination of T4 UvsX recombinase with single-stranded DNA.

T4 Gene 32 Protein is a single-stranded DNA binding protein required for bacteriophage T4 replication and repair. It coordinately binds and stabilizes the transiently formed ssDNA region and plays an important structural role in the process of T4 phage DNA replication. The protein has also been widely used to stabilize and label ssDNA regions in order to observe the structure of intracellular DNA with electron microscopy.

Bsu DNA Polymerase, derived from Bacillus subtilis, was obtained by truncating the first 296 AAs of the Bacillus subtilis DNA polymerase (Bsu) I gene. This polymerase retains its 5’→ 3’ DNA polymerase activity with its 5’→ 3’ exonuclease domain removed. Bsu DNA Polymerase naturally lacks the 3’→ 5’ exonuclease activity, which can be used for recombinase amplification.

Sau DNA polymerase is a DNA polymerase with strand displacement activity, which can be used for recombinase isothermal amplification. The protein-DNA complex formed by the combination of recombinant enzyme UvsX and primers can find homologous sequences in double-stranded DNA. Once the primer locates the homologous sequence, a strand displacement reaction will occur. Sau DNA polymerase starts DNA synthesis, and exponentially amplifies the target region on the template. The replaced DNA strand will bind to SSB to prevent further replacement.

Bst DNA/RNA Polymerase is a mixture of Bst polymerase and extremely thermostable reverse transcriptase (65°C tolerant), which is suitable for the isothermal amplification reaction of RNA. It can detect low-sensitivity RNA molecules. This enzyme is recommended in isothermal amplification experiments using RNA as a template. In addition, Bst DNA/RNA Polymerase can also perform isothermal amplification of DNA templates.

Exonuclease III was derived from E.coli, with 3 '- 5' exonuclease activity, acts on double-stranded DNA, and gradually cuts single nucleotides from the 3 'OH terminal direction. Each time the enzyme binds to the substrate for catalysis, only a few nucleotides are removed, resulting in progressive deletion within the DNA molecule group.

Endonuclease IV, also known as Nfo, is derived from E.Coli, involved in DNA damage repair. The enzyme can recognize the AP site (apurinic/apyrimidinic site) on double-stranded DNA, and cleave the first phosphodiester bond at the 5´ end of the AP site to generate 3´ hydroxyl groups and 5´ deoxyribose phosphate terminals.