ScrFI
CC▾NGG5′ overhang (1)
ScrFI is a 5 bp-recognition restriction enzyme. It runs best in rCutSmart at 37°C, and is prone to star activity under non-standard conditions.
NEB buffer activity
| Buffer | % Activity |
|---|---|
| rNEBuffer 1.1 | 100% |
| rNEBuffer 2.1 | 100% |
| rNEBuffer 3.1 | 100% |
| rCutSmartbest | 100% |
- Incubation
- 37°C
- Heat inactivation
- 65°C, 20 min
- Star activity
- Yes
- Methylation blocked
- Dcm, CpG
CCNGG. Dcm (CCWGG) overlaps directly -> blocked. CpG-context can block. 100% in all four buffers. NEB: star activity may result from extended digestion. Leaves a 1-base 5' extension that is harder to ligate than a blunt end.
Find ScrFI sites in your own sequence
Paste a sequence below and this scans it for every ScrFI recognition site — the same engine behind the full Restriction Sites tool, scoped to just this one enzyme.
Enzymes with ends compatible with ScrFI
ScrFI's overhang falls on a degenerate position of CCNGG (N), so which bases protrude depends on the template and compatibility cannot be settled from the enzyme alone.
Frequently asked questions
What does ScrFI recognize?
ScrFI recognizes the 5 bp sequence CCNGG (5′→3′), cutting the top strand between position 2 and 3 within the site to leave a 5′ overhang of 1 base.
What buffer should I use for ScrFI?
rCutSmart gives the highest activity (incubate at 37°C).
Does ScrFI have star activity?
Yes — under non-standard conditions (excess enzyme/glycerol, long incubation, low ionic strength) it can cleave at sites resembling but not matching CCNGG.
Is ScrFI blocked by DNA methylation?
Yes — blocked by Dcm, CpG methylation. Use methylation-free template (e.g. a dam⁻/dcm⁻ strain) if this matters for your digest.
Can I heat-inactivate ScrFI?
Yes — 65°C for 20 minutes.