How to find the right Lab Enzymes AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Lab Enzymes
- Polymerase fidelity
- Use a proofreading (3'→5' exonuclease) high-fidelity polymerase for cloning and sequencing templates; standard Taq is fine for genotyping and screening Taq lacks proofreading and introduces far more errors per base.
- Hot-start
- Choose hot-start formulations for multiplex, low-input or room-temperature setups They suppress primer-dimers and mispriming before the first denaturation step.
- Restriction enzyme buffer compatibility
- For double digests, check that both enzymes keep high activity in one buffer, and check for star activity at long incubations or high glycerol This avoids sequential digests and off-target cutting.
- Methylation sensitivity
- Check whether the site is blocked by Dam, Dcm or CpG methylation; use a dam-/dcm- host strain if needed Plasmid grown in standard E. coli can be uncuttable at overlapping sites.
- Overhang compatibility for TA cloning
- Proofreading polymerases leave blunt ends; use an A-tailing step or blunt cloning TA vectors need the 3'-A overhang that Taq adds.
- Storage
- Keep at -20 °C in a non-frost-free freezer; keep on a cold block during use Enzymes in glycerol lose activity with temperature cycling.
Brands that matter
- New England Biolabs: Reference catalog for restriction enzymes, ligases, polymerases and assembly kits, with detailed compatibility tools.
- Thermo Fisher Scientific (Thermo Scientific, Invitrogen): Broad catalog of restriction enzymes, polymerases and reverse transcriptases.
- Promega: Long-established line of PCR, RT and restriction enzymes.
- Takara Bio: Well-known high-fidelity polymerases and RT enzymes.
- Qiagen: PCR and RT enzymes, often bundled in kits.
- Roche: Enzymes for PCR, qPCR and molecular biology.
What to avoid
- Storing enzymes in frost-free freezers
- Using Taq for cloning when sequence accuracy matters
- Mixing enzymes with buffers from another brand without checking activity
- Shipments that arrive warm or without cold packs
Questions
What does a 'unit' mean?
Each supplier defines a unit as the amount of enzyme that completes a defined reaction under its own standard conditions. Units from different brands are not directly comparable.