This R package, seguid, implements SEGUID v2 together with the original SEGUID algorithm.
> library(seguid)
## Linear single-stranded DNA
> lsseguid("TATGCCAA")
[1] "lsseguid=EevrucUNYjqlsxrTEK8JJxPYllk"
## Linear single-stranded DNA
> lsseguid("AATATGCC")
[1] "lsseguid=XsJzXMxgv7sbpqIzFH9dgrHUpWw"
## Circular single-stranded DNA
> csseguid("TATGCCAA")
[1] "csseguid=XsJzXMxgv7sbpqIzFH9dgrHUpWw"
## Same rotating two basepairs
> csseguid("GCCAATAT")
[1] "csseguid=XsJzXMxgv7sbpqIzFH9dgrHUpWw"
> library(seguid)
## Linear double-stranded DNA
> ldseguid("AATATGCC", "GGCATATT")
[1] "cdseguid=dUxN7YQyVInv3oDcvz8ByupL44A"
## Same swapping Watson and Crick
> ldseguid("GGCATATT", "AATATGCC")
[1] "cdseguid=dUxN7YQyVInv3oDcvz8ByupL44A"
## Circular double-stranded DNA
> cdseguid("TATGCCAA", "TTGGCATA")
[1] "cdseguid=dUxN7YQyVInv3oDcvz8ByupL44A"
## Same swapping Watson and Crick
> cdseguid("TTGGCATA", "TATGCCAA")
[1] "cdseguid=dUxN7YQyVInv3oDcvz8ByupL44A"
## Same rotating two basepairs (= minimal rotation by Watson)
> cdseguid("AATATGCC", "GGCATATT")
[1] "cdseguid=dUxN7YQyVInv3oDcvz8ByupL44A"