Let's say the plant-gene itself is known, i.e. the exact neucleotide sequence is available in a gene bank (originally sequenced from a tree sample extracted RNA). Previous work has already successfuly inserted & expressed the gene in a host bacterium, say, E Coli.
My question is: Does subsequent work on inserting the gene into other host organisms also have to start from tree samples as source of the RNA & hence DNA?
Or is there a more direct route to convert a Neucleotide sequence from a gene database into actual DNA that can be inserted into hosts?
e.g. Are there machines that can take a sequence & synthesize the correct DNA molecules? Or not yet?