Protein sequence in, E. coli-optimized DNA out.
ΔG is the folding energy of the first 48 nucleotides. We pick the candidate that folds most weakly — closest to zero — because strong hairpins near the start codon suppress translation initiation.
Results vary between runs. Candidate generation is random, so the same protein gives a different but comparable sequence each time. Save what you get; re-requesting won't reproduce it.
Unavoidable motifs counts forbidden sequences we couldn't remove because the residues force them — a lysine run compels AAA AAA, which contains AAAAA. Non-zero means the returned DNA still contains them, so check before ordering synthesis.