Appeal No. 1998-0529
Application No. 07/961,076
references, Wong, Ichikawa (I), and Ichikawa (II), disclose an analogous process wherein
sialyl carbohydrate is produced by transferring a sialyl group to a carbohydrate from a
donor molecule, e.g. cytidine monophosphate-sialic acid (CMP-sialic acid), in the
presence of a sialyl transferase and wherein the donor molecule CMP-sialic acid is
regenerated in situ using sialic acid, a CMP-sialic acid synthetase and the CMP from
which the sialyl has been removed. (E.g., Wong, col. 5, line 66 - col. 6, line 37, and Figure
1).
In order to establish a prima facie case of obviousness on the facts before us, the
examiner must have provided evidence which would have led one of ordinary skill in this
art, at the time of the invention, to the claimed method of producing a fucosylated
carbohydrate. Even if we assume for purposes of argument that one of ordinary skill in this
art would have been motivated by Wong, Ichikawa (I), and/or Ichikawa (II) to try modifying
the process disclosed in Gokhale in order to regenerate the donor molecule in situ, it
remains that we have not yet reached the presently claimed method. Claim 1 requires
"recycling in situ the nucleoside 5'-phosphate with fucose to form the corresponding
nucleoside 5'-diphospho-fucose." (Claim 1). On this record, the examiner has provided no
facts or evidence which would suggest how this is to be accomplished. To the extent that
the examiner would urge the substitution of fucose for the sialic acid in the secondary
references, it has not been demonstrated that one of ordinary skill in this art led to this
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