Masterase is a 43.3 kDa heat-labile recombinant endonuclease, derived from a cold water eukaryotic organism, expressed in Pichia pastoris. The enzyme displays high specific activity towards double-stranded DNA leaving single-stranded DNA or RNA undamaged in standard conditions.

Masterase can be easily inactivated by heat treatment in moderate temperatures. It is intended for applications where the presence of dsDNA influences experiments’ results in thermo-sensitive applications and it is extremely useful for rapid and safe purification of RNA or proteins samples from contaminating DNA.

The enzyme hydrolyzes phosphodiester linkages yielding oligonucleotides with a 5′-phosphate and a 3′-hydroxyl groups.

Features and advantages

• Highly active in a broad temperature range (10 – 47°C).
• Low-temperature activity to protect RNA or proteins.
• Highly active in typical buffer formulations and broad pH range (optimum at 7.0 – 8.0).
• Requires at least 2 mM Mg²⁺ ions for optimal activity.
• Irreversible inactivation at low temperature (15 min at 52°C, 1 mM DTT) to secure biological product’s integrity.
• The activity towards dsDNA is at least 1000 times higher than towards ssDNA.

Applications

• dsDNA digestion (plasmid DNA, genomic DNA, etc.).
• RNA and protein samples rapid purification.
• PCR, qPCR Master Mixes, or other diagnostic reagents decontamination.
• Degradation of DNA template in transcription reactions.

Unit definition

One unit (U) is defined as the amount of enzyme that causes an increase in absorbance at 260 nm of 1.0 in 30 minutes at 37°C in 50 mM Tris-HCl buffer, pH 8.0 (25°C) supplemented with 5 mM MgCl₂, 0.1 mg/ml BSA and 0.5 mg/ml herring sperm DNA as a substrate.