Ex parte JEM

Board of Patent Appeals and Interferences

Sep 27, 2001

08393321 (B.P.A.I. Sep. 27, 2001)

The opinion in support of the decision being entered today was not written for publication
and is not binding precedent of the Board.
Paper No. 18
UNITED STATES PATENT AND TRADEMARK OFFICE
____________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________
Ex parte KWAN-MIN J. JEM
____________
Appeal No. 1999-1425
Application No. 08/393,321
____________
ON BRIEF
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Before ROBINSON, SCHEINER, and ADAMS, Administrative Patent Judges.
ROBINSON, Administrative Patent Judge.
DECISION ON APPEAL
This is a decision on the appeal under 35 U.S.C. § 134 from the examiner's final
rejection of claims 1 - 26, which are all of the claims pending in the application.
Claims 1 and 10 are illustrative of the subject matter on appeal and read as follows:
1. A mechanical method for disruption of plasmid-containing bacterial cells and
release of intact plasmid DNA, comprising the steps of:
a) passing liquid suspension of plasmid-containing bacterial cells through an
impinging-jet homogenizer with a single interaction chamber at an operating pressure of
about 750 to 4,000 psi, whereby the bacterial cells are disrupted and intact plasmid DNA
is released, producing a liquid that contains intact plasmid DNA and disrupted bacterial
cell debris; and
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b) separating the disrupted bacterial cell debris from the liquid containing intact
plasmid DNA.
10. A mechanical method for disruption of plasmid-containing bacterial cells and
release of intact plasmid DNA, comprising the steps of:
a) passing liquid containing plasmid-containing bacterial cells through a bead mill
containing beads of about 0.1 mm to about 1 mm in diameter, at an agitation speed of
about 1,000 to 2,500 rpm, wherein the liquid is processed in the bead mill, for a total
residence time in the bead mill of at least about 3 minutes, whereby bacterial cells are
disrupted and intact plasmid DNA is released; and
b) separating the disrupted bacterial cell debris from the liquid containing intact
plasmid DNA.
The references relied upon by the examiner are:
Agerkvist et al. (Agerkvist) “Characterization of E. Coli. Cell Disintegrates from a
Bead Mill and High Pressure Homogenizers,” Biotechnology and Bioengineering,
Vol. 36, pp. 1083-1089 (1990)
Sambrook et al.(Sambrook) “Extraction and Purification of Plasmid DNA,”
Molecular Cloning: A Laboratory Manual, 2nd Edition, Cold Spring Harbor Press
Sect 1.21-1.52 (1989)
Sauer et al. (Sauer) Disruption of Native and Recombination Escherichia Coli in a
High-Pressure Homogenizer,” Biotechnology and Bioengineering, Vol. 33,
pp. 1330-1342 (1989)
Johnson “Isolation and Purification of Nucleic Acids,” Nucleic Acid Techniques in
Bacterial Systematics, Stackebrandt et al., eds., John Wiley & Sons, New York, NY., pp. 1-
19 (1991)
Grounds of Rejection
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Claims 1 - 9 stand rejected under 35 U.S.C. § 103. As evidence of obviousness,
the examiner relies on Sambrook and Sauer.
Claims 10 - 26 stand rejected under 35 U.S.C. § 103. As evidence of obviousness,
the examiner relies on Sambrook, Johnson, and Agerkvist.
We reverse for reasons set forth herein.
Discussion
In reaching our decision in this appeal, we have given careful consideration to the
appellant’s specification and claims and to the respective positions articulated by the
appellant and the examiner. We make reference to the Examiner's Answer of December
9, 1997 (Paper No. 13) for the examiner's reasoning in support of the rejections and to the
appellant’s Appeal Brief, filed August 23, 1997 (Paper No. 12), for the appellant’s
arguments thereagainst.
Background
Applicant describes the claimed invention at pages 6 and 7 of the Specification as
being directed to a mechanical method for disrupting plasmid-containing bacterial cells
and, thus, releasing the intact plasmid DNA which can then be isolated. One such method
comprises the steps of first passing a liquid suspension of plasmid-containing bacterial
cells, between one and three times, through an impinging-jet homogenizer with a single
interaction chamber at operating pressure of about 750 to 4000 psi, whereby the bacterial
cells are disrupted and the intact plasmid DNA is released. Appellant describes a second
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method comprising the steps of first passing liquid containing plasmid-containing bacterial
cells through a bead mill containing beads of about 0.1 mm to about 1 mm in diameter, at
an agitation speed of about 1,000 to 2,500 rpm. Appellant explains that the use of such
lower-speed agitation disrupts cells with minimal damage to the DNA plasmids contained
therein.
The rejections under 35 U.S.C. § 103
The examiner's rejection of claims 1 - 9 depends on the combined teachings of
Sambrook and Sauer.
The examiner relies on Sambrook as describing the isolation of plasmids from host
cells using many methods to first disrupt the host cells. (Answer, page 4). The examiner
acknowledges that Sambrook does not teach the use of microfluidization disruption as a
feasible method for plasmid isolation. (Id.). The examiner cites Sauer as teaching the
disrupting of cells using a microfluidizer to isolate intracellular components at 30 - 95 MPa.
(Answer, page 5). Therefore, the examiner urges that (Answer, page 4):
[i]t would have been obvious at the time the invention was made to isolate
plasmid DNA from cells using a microfluidizer given that Sauer teaches that
microfluidization is a good method for disrupting cells to recover their
components.
In rejecting claims under 35 U.S.C. § 103, the examiner bears the initial burden of
presenting a prima facie case of obviousness. In re Oetiker, 977 F.2d 1443, 1445, 24
USPQ2d 1443, 1444 (Fed. Cir. 1992). Only if that burden is met, does the burden of
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coming forward with evidence or argument shift to the applicants. Id. In order to meet that
burden the examiner must provide a reason, based on the prior art, or knowledge
generally available in the art as to why it would have been obvious to one of ordinary skill in
the art to arrive at the claimed invention. Ashland Oil, Inc. v. Delta Resins & Refractories,
Inc., 776 F.2d 281, 297, n.24, 227 USPQ 657, 667, n.24
(Fed. Cir.), cert. denied, 475 U.S. 1017 (1986).
On the record before us, the examiner has not met the initial burden of establishing
why the prior art, relied on, would have led one of ordinary skill in this art to arrive at the
method of claims 1 - 9. Sambrook, while isolating plasmids from cells by disrupting the
cells does not describe any “mechanical” methods of doing so. Sauer, while describing
the mechanical disruption of cells using a microfluidizer, is concerned with isolating
proteins (page 1330, column 1, first paragraph of the Introduction) and does not suggest
that the methodology described would be suitable for use in isolating intact DNA plasmids.
Further, we have the statement from Sambrook which suggests that large plasmids are
susceptible to damage and should be released from cells by gentle lysis. (Page 1.22,
paragraph 1). Thus, in our opinion, the examiner has provided no evidence or facts which
could reasonably be read to suggest or direct one of ordinary skill in this art to use the
microfluidizer of Sauer in the plasmid isolation process of Sambrook.
In addition, neither reference suggests or describes the use of an operating
pressure of 750 to 4,000 psi. While the examiner urges that it would be a matter of routine
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experimentation to optimize the disruption of the cells while not damaging the plasmids to
be isolated, the examiner has provided no evidence or facts which would guide those of
ordinary skill in this optimization process. Before one can optimize a process, there must
first be the process. We do not doubt, that the mechanical disruption of Sauer could be
applied in some manner to cells to isolate intact plasmids. However, the fact that the prior
art could be so modified would not have made the modification obvious unless the prior art
suggested the desirability of the modification. In re Gordon, 733 F.2d 900, 902, 221
USPQ 1125, 1127 (Fed. Cir. 1984). In re Fritch, 972 F.2d 1260, 1266, n.14, 23 USPQ2d
1780, 1783-84, n.14 (Fed. Cir. 1982).
In the absence of such evidence, the only suggestion to perform the assay in the
manner presently claimed, is provided by appellant's disclosure of the invention. However,
use of this information as a basis for establishing a prima facie case of obviousness,
within the meaning of 35 U.S.C. § 103, would constitute impermissible hindsight. There
must be some reason, suggestion, or motivation found in the prior art whereby a person of
ordinary skill in the field of the invention would make the modifications required. That
knowledge can not come from the applicants' invention itself. Diversitech Corp. v. Century
Steps, Inc., 850 F.2d 675, 678-79, 7 USPQ2d 1315, 1318 (Fed. Cir. 1988); In re Geiger,
815 F.2d 686, 688, 2 USPQ2d 1276, 1278 (Fed. Cir. 1987); Interconnect Planning Corp.
v. Feil, 774 F.2d 1132, 1143, 227 USPQ 543, 551 (Fed. Cir. 1985). Since that reason,
suggestion or motivation is missing from this record, we can not agree that the examiner
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has provided those facts or evidence which would reasonably support a conclusion that the
claimed subject matter would have been prima facie obvious within the meaning of 35
U.S.C. § 103. Where the examiner fails to establish a prima facie case, the rejection is
improper and will be overturned. In re Fine, 837 F.2d 1071, 1074, 5 USPQ2d 1596, 1598
(Fed. Cir.1988). Therefore, the rejection of claims 1 - 9 under 35 U.S.C. § 103 is
reversed.
The examiner’s rejection of claims 10 - 26 under 35 U.S.C. § 103 as obvious over
the combination of Sambrook, Johnson and Agerkvist is similarly flawed. While relying on
Sambrook as discussed supra, the examiner relies on Johnson as teaching the use of a
bead mill to disrupt cells, including the use of beads of a size which would appear to
correspond, at least to some degree, to that required by the claims. (Answer, page 6).
The examiner acknowledges that Johnson “does not teach all of the limitations claimed by
appellant.” (Id.). However, the examiner urges that “[t]he Johnson procedure could be
modified by routine experimentation to produce a method using lower rotation speeds and
larger beads.” (Id.). While indicating that the use of glass bead disruption “does not
fragment DNA to the extent resulting from sonication or passage through a French
pressure cell . . . . ” (Johnson, page 5, paragraph c), Johnson does not suggest that the
technique could be used to isolate “intact DNA plasmids” as presently claimed. Similarly,
Agerkvist, in describing Figure 3 states that “the DNA polymer is shear sensitive and will
be irreversibly degraded to smaller fragments during the experiment.” The examiner offers
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no evidence which would reasonably guide one of ordinary skill as to how to modify the
methodology of either Johnson or Agerkvist in a manner to arrive at the method of the
rejected claims. It is not enough that these methods could be modified, with or without
experimentation, to arrive at the claimed invention unless these is something to be found in
the prior art which would direct those of ordinary skill in the process. That direction or
suggestion is not present on this record. Thus, we conclude that the examiner has failed to
provide sufficient evidence to reasonably support a conclusion of obvious within the
meaning of 35 U.S.C. § 103 as to the method presently claimed. Therefore, we reverse
the rejection of claims 10 - 26 under 35 U.S.C. § 103.
Summary
The rejection of claims 1 - 9 under 35 U.S.C. § 103 as unpatentable over the
combined teachings of Sambrook and Sauer is reversed. The rejection of claims
10 - 26 under 35 U.S.C. § 103 over the combined teachings of Sambrook, Johnson, and
Agerkvist is reversed.
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REVERSED
Douglas W. Robinson )
Administrative Patent Judge )
)
)
) BOARD OF PATENT
Toni R. Scheiner )
Administrative Patent Judge ) APPEALS AND
)
) INTERFERENCES
)
Donald E. Adams )
Administrative Patent Judge )
Mary E. Bak
Howson & Howson
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