"artificial sequence" is any sequence not taken from nature. The spider silk protein gene is not an artificial sequence nor is the heptcidin sequence that KBLB plans to use to add antibiotic properties to silk as both are derived from nature (the heptcidin gene comes from Homo spaiens).
KBLB is planning on adding a completely artificial sequence to silkworms to produce an artificial protein designed to give a fiber with (hopefully) superior properties to any existing fiber. (They mentioned that in a PR last year)
If successful it would prove the platform worm concept and be WAY bigger than pure spider silk, IMHO.