DETAILED CORRESPONDENCE
Application Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Applicant has support for the new claims 22-25.
A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 8/13/2026 has been entered.
Applicant’s amendment to the claims filed on 8/13/2026 in response to the Final Rejection mailed on 4/14/2026 is acknowledged. This listing of claims replaces all prior listings of claims in the application.
Claims 1-11, 16-20, 22-25 are pending and examined on the merits.
Claims 12-15, 21 are cancelled.
Applicant’s remarks filed on 8/13/2026 in response to the Final Rejection mailed on 4/14/2026 have been fully considered and are deemed persuasive to overcome at least one of the rejections and/or objections as previously applied.
The text of those sections of Title 35 U.S. Code not included in the instant action can be found in the prior Office Action.
Withdrawn Rejections
The rejection of claims 12-13, 15, 21 under 35 U.S.C. 101 is withdrawn in view of cancellation of claims 12-15, 21.
The rejection of claims 12-13, 15, 21 under 35 U.S.C. 103 as being unpatentable over Darveau et al (1983, Journal of Bacteriology, Examiner cited) {herein Darveau} in view of Agilent Technologies (2017, cited on PTO-892 filed 5/21/2024) {herein Agilent} as evidenced by Lumen et al (2025, Lipids, Biology for Majors, cited on PTO-892 dated 6/2/2025) {herein Lumen} is withdrawn in view of cancellation of claims 12-13, 15, 21.
New Claim Rejections - 35 USC § 112
The following is a quotation of 35 U.S.C. 112(b):
(b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.
The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph:
The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention.
Claims 6-9, 19-20 are newly rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. The new rejection is necessitated by the recitation of ‘a first step’ in claims 6-9, 19-20 of which Applicant does not have any antecedent basis.
Claims 6-9, 19-20 recites the limitation "the first step" in lines 2. There is insufficient antecedent basis for this limitation in the claim. There is no prior recitation of ‘a first step’ in claim 1, upon which claims 6-9 depends. Appropriate correction is suggested.
Maintained Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
The rejection of claims 1-11, 16-20, 22-23 under 35 U.S.C. 103 as being unpatentable over Darveau et al (1983, Journal of Bacteriology, Examiner cited) {herein Darveau} in view of Agilent Technologies (2017, cited on PTO-892 filed 5/21/2024) {herein Agilent} as evidenced by Lumen et al (2025, Lipids, Biology for Majors, cited on PTO-892 dated 6/2/2025) {herein Lumen} is maintained. The rejection has been modified to remove cancelled claims 13, 15, 21 and add new claims 22-23.
With respect to claims 1, 6-10, 22-23 Darveau teaches a method wherein LPS from Salmonella and Escherichia are isolated without using organic solvent (page 832, column 1, para 4; column 2, para 4). The method comprises suspending dried cells in Tris-hydrochloride buffer, RNase A and French pressing the cells twice (page 832, column 2, para 4). Subsequently, the suspension is incubated at 37C for 2hrs (page 832, column 2, para 4). Afterwards, tetraosodium EDTA, Tris-hydrochloride and SDS are added to the suspension (page 832, column 2, para 4). The sample is vortexed, centrifuged and incubated on a shaker at 37C overnight (page 832, column 2, para 4). Next, MgCl2 in ethanol is added and the sample is cooled to 0C (page 832, column 2, para 4). The pellet obtained is suspended in SDS-tetrasodium EDTA, Tris-hydrocholoride and sonicated (page 833, column 1, para 1). The solution is then incubated at 85C for 10-30min (page 833, column 1, para 1). The solution is centrifuge (page 833, column 1, para 2). Next, the pellet which contains LPS is resuspended in distilled water (page 833, column 1, para 2). The LPS is subsequently purified utilizing SDS-PAGE followed by Silver Staining (page 833, column 2, para 2).
With respect to claim 11, it would be obvious to one of ordinary skill in the art that the LPS produced by a gram-negative bacterium belonging to the genus Pantoea would be purified by the method taught by Darveau as Darveau teaches LPS is successfully extracted from gram negative bacteria without using organic solvent (page 832, column 1, para 4; column 2, para 4).
With respect to claims 19-20, Darveau teaches a method wherein the suspension is incubated at 37C for 2hrs (page 832, column 2, para 4). Absent evidence otherwise, it is the Examiner’s position that incubating the suspension at 37C for 2 hrs is within the first step of isolation of LPS without using organic solvent. Although the references of Darveau in view of Agilent do not explicitly teach the limitations of claims 19-20 (the first step is 50 to 150°C), MPEP 2144.05 states"[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation." In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) (MPEP 2144.05 IIA)." One of ordinary skill would desire to optimize the temperature of the hot water depending on the particular application. It would be routine for one to arrive at the temperature for the application they intend on using the LPS. Therefore, the above invention would have been prima facie obvious.
However, Chen does not teach a second step of purifying the extract liquid or a solution containing the LPS in the extract liquid by using reverse-phase liquid chromatography to obtain the lipopolysaccharide, wherein a reverse-phase column used in the reverse-phase liquid chromatography has a packing material constituted of a material having a functional group of 1 to 8 carbons (claim 1). The lipopolysaccharide production method according to Claim 1, wherein the packing material is constituted of a material having a functional group of 2 to 6 carbons (claim 2). The lipopolysaccharide production method according to Claim 1, wherein the packing material is constituted of a material having a functional group of 2 to 4 carbons (claim 3). The lipopolysaccharide production method according to Claim 1, wherein the packing material is constituted of a material having a functional group of 4 carbons (claim 4). The lipopolysaccharide production method according to Claim 1, wherein the functional group is an alkyl group (claim 5). The lipopolysaccharide production method according to Claim 2, wherein the packing material is constituted of a material having a functional group of 2 to 4 carbons (claim 16). The lipopolysaccharide production method according to Claim 2, wherein the packing material is constituted of a material having a functional group of 4 carbons (claim 17). The lipopolysaccharide production method according to Claim 2, wherein the functional group is an alkyl group (claim 18).
With respect to claims 1-4, 16-18, Agilent teaches a method wherein reverse phase chromatography is used for the purification of macro molecules with nonpolar hydrocarbon chains (page 19). Evidentiary reference of Lumen is cited to demonstrate that lipids are hydrocarbons that are mostly nonpolar hydrophobic molecules (page 2, para 1). As such, it would be obvious to one of ordinary skill that reverse-phase chromatography could be used for the purification of LPS as LPS contains a hydrophobic lipid A region with nonpolar hydrocarbon chains. Furthermore, the silica gels in the column stationary phase are the packing material with the hydrocarbon chains between 1 and 18 carbon atoms as the functional group because they function to separate the mixture (page 19). Examiner is interpreting 1 to 8 carbons claimed by Applicant to encompass 1 to 18 carbons taught by Agilent. A prima facie case of obviousness exists where the claimed ranges and prior art ranges overlap, such as in the instant rejection. MPEP § 2144.05.
With respect to claims 5, 18, Agilent teaches a method wherein the packing material has an alkyl functional group (page 27).
Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to combine the teachings of Darveau and Agilent because Agilent teaches a method wherein reverse phase chromatography is used for the purification of macromolecules (page 47, para 2). While Darveau teaches a method wherein LPS from Salmonella and Escherichia are isolated without using organic solvent (page 832, column 1, para 4; column 2, para 4).
One of ordinary skill in the art would have had a reasonable expectation of success, a reasonable level of predictability, and would be motivated to combine the teachings of Darveau and Agilent because Agilent provides the motivation for Darveau to substitute the purification of LPS taught by Darveau with reverse phase chromatography, taught by Agilent, since Agilent establishes that the packed column in reverse liquid chromatography with the alkyl functional group is successful for the purification of macro molecules with nonpolar hydrocarbon chains, of which is a property of LPS (page 19). In addition, Darveau would be motivated to substitute reverse-based chromatography for SDS-PAGE and Silver Staining for the analysis/characterization of LPS as utilizing reverse-phase chromatography would allow Darveau to achieve high sensitivity and quantitative analysis of LPS, with minimal artifacts. Thereby utilizing the purification method taught by Agilent would allow Darveau to better analyze the endotoxin obtained from the bacterium. MPEP 2143.I.B states “The rationale to support a conclusion that the claim would have been obvious is that the substitution of one known element for another yields predictable results to one of ordinary skill in the art.” Additionally, substituting the SDS-PAGE and silver staining with the reverse-phase chromatography would provide a more time-efficient method of the detection and characterization of the endotoxin taught by Darveau. One of skill in the art would have a reasonable expectation of success to make and use the claimed LPS extraction and purification method because Darveau provides the basic method for extracting LPS and its uses and methods of making it. Agilent provides the steps of reverse-phase liquid chromatography for the purification of macromolecules with nonpolar hydrocarbons for optimized resolution.
One of ordinary skill in the art would be motivated to combine the teachings of Darveau and Agilent because doing so would produce isolated and purified LPS at higher concentrations with less artifacts (contaminants). Furthermore, the extraction method taught by Darveau is routinely done within the art, since 1983 (date of the art), therefore the supplies for the method are widely available. As such, one of skill in the art would be motivated to utilize said methods for the isolation and purification of LPS. Therefore there would be a reasonable expectation of success to arrive at the above invention. Therefore, the above invention would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention.
RESPONSE TO REMARKS: Beginning on p. 6 of Applicant’s remarks, Applicant contends that the method of Darveau does not use water at all.
The argument is not persuasive. Examiner contends that Darveau’s method relies upon aqueous solutions with the recitation ‘dried bacterial cells were suspended in …’ (page 832, column 2, para 4); ‘the suspension was then incubated at 37°C for 2 h’ (page 832, column 2, para 4), etc.
Applicant contends that in Darveau page 836 (ii), it states "[w]e found that when the properties of the SDS-resistant (pronase-resistant) proteins were not known, 30 min at 85°C was sufficient to ensure complete protein removal by subsequent steps." (emphasis added). The subsequent steps referred to here are the actual extraction steps described on p. 832. Applicant contends that the fact that the heating referred to on page 836 does not state it is achieved via hot water, there is no step in the actual extraction procedure of Darveau where hot water is used. Applicant contends that This alleged hot water preheating step is completely inferred and injected into Darveau's procedure.
The argument is not persuasive. Examiner contends that the teaching of Darveau of ‘the solution was then incubated at 85°C for 10 to 30 min to ensure the denaturation of SDS-resistant proteins like membrane porins outer’ (page 833, column 1, para 1) is the same as the extraction of LPS using hot water, as recited in the instant application claim 1, since a solution that is 85C is well-understood in the art to be comprised of ‘hot water.’ Furthermore, Darveau provides the motivation for one that is extracting LPS from a gram-negative bacteria to heat the solution with the bacteria to 85C as it would ensure the denaturation of SDS-resistant proteins like membrane porins outer (page 833, column 1, para 1). Examiner contends that the assertion by Applicant that the teaching by Darveau of ‘"[w]e found that when the properties of the SDS-resistant (pronase-resistant) proteins were not known, 30 min at 85°C was sufficient to ensure complete protein removal by subsequent steps."’ (page 833, column 1, para 1) with subsequent steps to be on page 832 is unfounded. Especially since immediately following said teaching by Darveau on page 833, column 1, para 1, Darveau teaches after cooling, the pH was raised (if previously lowered) to 9.5 by the addition of 4 N NaOH. This was found be to necessary for successful protein removal in subsequent steps (page 833, column 1, para 1). Furthermore, Examiner contends that Applicant’s recitation of ‘performing extraction from the gram-negative bacterium using hot water’ within the instant application claims 1, 24-25 doe does not preclude the ‘hot water’ from being a component of a solvent due to the recitation ‘comprising.’ Regarding the recitation ‘performing extraction from the gram-negative bacterium using hot water to obtain an extract liquid that contains the lipopolysaccharide, wherein performing extraction does not use organic solvent,’ since the structure of a method for extracting LPS from gram negative bacteria is taught by Darveau, it is the Examiner’s position that said method would necessarily result in the acquisition of an extract liquid that contains LPS.
Applicant contends that in Darveau, the extraction occurs by way of the enzymes, not any hot water, even if it were true that hot water was used before or after the enzyme treatment.
The argument is not persuasive. Examiner contends that the claimed limitations do not recite a method of LPS extraction and purification ONLY using hot water. Nor does Applicant disclose said method within the instant application specification. Therefore, the art of Darveau is properly applied based on Applicant’s own claim language and in light of the instant application specification.
Allowable Subject Matter
Claims 24-25 are allowable over the prior art as there is no prior art that teaches ‘an extraction step consisting of performing extraction from the gram-negative bacterium using hot water to obtain an extract liquid from the gram-negative bacterium that contains the lipopolysaccharide’ (instant application claim 24) and ‘the lipopolysaccharide production method comprising: performing extraction from the gram-negative bacterium using a solvent consisting of hot water to obtain an extract liquid that contains the lipopolysaccharide’ (instant application claim 25).
Conclusion
Status of Claims
Claims 1-11, 16-20, 22-23 are pending and examined on the merits.
Claims 12-15, 21 are cancelled.
Claims 24-25 are allowable.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to ERICA NICOLE JONES-FOSTER whose telephone number is (571)270-0360. The examiner can normally be reached mf 7:30a - 4:30p.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Manjunath Rao can be reached at 571-272-0939. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/ERICA NICOLE JONES-FOSTER/Examiner, Art Unit 1656
/MANJUNATH N RAO/Supervisory Patent Examiner, Art Unit 1656
