Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Continued Examination Under 37 CFR 1.114
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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 02/17/2026 has been entered.
DETAILED ACTION
Claims 1, 3, 4, 6, 8, 11, 22, 28, 30-32, 34, 41-42, 44 and 46-52 are pending.
Claims 28, 30-32, 34, 41-42, 44 and 46-48 are withdrawn from further consideration as being drawn to a nonelected invention.
Claims 1, 3, 4, 6, 8, 11, 22 and 49-52 are under examination and are entitled to an effective filing date of 21 March, 2019.
The rejection of claims 1, 3, 4, 6, 8, 11, 22 and 49-51 under 35 U.S.C. 103 as being unpatentable over Suthiwangcharoen in view of Sakr and Khan is withdrawn.
Claim Rejections - 35 USC § 103
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.
Claims 1, 3, 4, 6, 8, 11, 22 and 49-52 are rejected under 35 U.S.C. 103 as being unpatentable over Suthiwangcharoen (Biomacromolecules, 2014, 15(3): 948-956; as cited in the IDS 04/062020, and provided herein with supplemental information) in view of Han (ACS Sustainable Chemistry & Engineering, 2018, 6(6), 7779-7788) and Chang (Protein Science, 28(4), 794-799; published 01/27/2019).
Claim 1 requires two active method steps. First, an aqueous phase comprising a carbohydrate-activated enzyme (CAZyme) is admixed with a dispersed phase comprising a pyridine polymer, such as P4VP. The purpose of this first step is to form a droplet dispersion in the aqueous phase. Second, the admixture is dialyzed against an aqueous dialysis solution comprising 250 mM of a salt, such as NaCl. The purpose of this second step is to remove unreacted or free enzyme and solvent. The formed product is a biocatalyst having a polymer core and enzyme shell. The CAZyme can be cellulase or beta-glucosidase. See [0037] of the instant specification.
Regarding claim 1, Suthiwangcharoen teaches preparing polymer-protein core-shell nanoparticles (PPCS-NPs) as an alternative noncovalent approach. See the left column on page 948. Suthiwangcharoen teaches adding a solution of poly(4-vinylpyridine) (P4VP) in dimethylformamide (DMF) or ethanol (i.e. dispersed phase) into a solution of proteins in phosphate saline buffer (i.e. an aqueous phase). The mixtures are dialyzed against PBS, if DMF is used. Upon removing the organic solvent by dialysis, dispersed particles with P4VP are formed. See the first paragraph in the right column on page 949 and left column on page 951. Proteins include enzymes, such as lipase. See the second paragraph of the materials section, table S1 and figure 3. Polymers containing a pyridine unit are able to spontaneously self-assemble with proteins to form spherical colloid particles. See the second full paragraph on page 954. Suthiwangcharoen suggests that the model proteins are shown to maintain as high as 90% of their original biological activities. See the right column on page 948.
Suthiwangcharoen does not teach a carbohydrate-activated enzyme.
Han teaches immobilizing cellulase and β-glucosidase onto poly(methacrylamide-co-acrylic acid) (PMAAc) to form a PMAAC-cellu&β-G biocatalyst. Han teaches covalently bonding the cellulase to PMAAc. See the third paragraph in the right column on page 7780 and second full paragraph in the right column on page 7781. Han suggests that cellulases have enormous biotechnical potential prospects in various industries, but native cellulase can be easily deactivated during long-time operation. Han suggests that adding β-glucosidase can result in higher hydrolysis efficiency. See the left column and abstract on page 7779.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to substitute the cellulase and/or β-glucosidase of Han for the protein in the polymer-protein core-shell nanoparticle (PPCS-NPS) of Suthiwangcharoen. One of ordinary skill in the art would have been motivated to do so because Han suggests that cellulases have enormous biotechnical potential (p. 7779, left column, last sentence). There would be a reasonable expectation of success because Han teaches covalently bonding a polymer to cellulase and β-glucosidase, and Suthiwangcharoen demonstrates an alternative noncovalent approach to preparing PPCS-NPs.
Suthiwangcharoen and Han do not teach dialyzing the admixture against an aqueous dialysis solution comprising 250 mM of a salt.
Chang teaches a protein, HLB5, that is capable of degrading cellulosic biomass. See the second paragraph of page 795. Chang teaches dialyzing the protein in 20 mM pH 8 HEPES (i.e. aqueous dialysis solution), 250 mM NaCl. See the first passage of the right column on page 795.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to add Chang’s dialysis step in Suthiwangcharoen’s method, as modified by Han’s CAzymes. One of ordinary skill in the art would have been motivated to add the dialysis step of Chang because Chang’s dialysis produced a novel cellulase with high activity (p. 795, left column, first full paragraph).
Regarding claim 3, Suthiwangcharoen teaches polymers containing a pyridine unit, such as P4VP (poly(4-vinylpyridine)), poly(2-vinylpyridine), or PCL-b-P2VP (poly(caprolactone)-block-poly(2-vinylpyridine)), and suggests that such polymers are able to spontaneously self-assemble with proteins to form spherical colloidal particles. See the third paragraph on page 954.
Regarding claim 4, Suthiwangcharoen teaches altering the pH of the solution to control surface charges of proteins and see how it could impact the assembly of proteins with different pIs. In all situations, colloids were evident only at pH > pI, where proteins carry a net negative charge. See the right column on page 953. Suthiwangcharoen suggest that negatively charged proteins are required for a successful assembly. See the first passage on page 954.
Regarding claim 6, Suthiwangcharoen teaches a mechanism based on hydrogen bonding between proteins and polymer. See the abstract. Suthiwangcharoen suggests that the pyridine units of P4VP can serve as a hydrogen bond donor or acceptor. See the second full paragraph on page 954.
Regarding claim 8, Suthiwangcharoen teaches adding a solution of poly(4-vinylpyridine) (P4VP) in dimethylformamide (DMF) (i.e. a solvent) or ethanol (i.e. a solvent) into a solution of proteins in phosphate saline buffer. See the first paragraph in the right column on page 949.
Regarding claim 11, Suthiwangcharoen teaches placing the mixtures at room temperature to allow ethanol to completely evaporate. See the right column on page 494.
Regarding claim 22, Suthiwangcharoen teaches spherical particles with a hydrodynamic diameter of about 150−250 nm. See the last passage on page 952 and figures 1(b) and 1(e).
Regarding claims 49-50, Chang teaches 250 mM NaCl (i.e. sodium chloride). See the first passage in the right column on page 795.
Regarding claim 51, Chang teaches dialyzing the protein in 20 mM pH8 HEPES (i.e. aqueous dialysis solution), 250 mM NaCl. See the first passage of the right column on page 794.
Claim 52 requires the method to further comprise admixing the polymer core with a second enzyme that is the same as or different from the CAZyme. The purpose of this step is to recharge an exhausted enzyme shell assembled on the polymer core. The point at which the enzyme becomes exhausted is not defined. Therefore, claim 52 encompasses using the biocatalyst of claim 1 to exhaust the enzyme shell to any extent, and then adding a second enzyme.
Regarding claim 52, Han teaches coimmobilizing cellulase and β-glucosidase on PMAAC. The reusability of the coimmobilized enzyme is investigated by the hydrolysis of insoluble microcrystalline cellulose into glucose for 8 cycles. See the second paragraph and last passage in the right column on page 7781. Han teaches supplementing an extra amount of catalyst after each recycling process. See the last passage of the left column on page 7785 and figures 10 and 11. Han suggests that the reusability of a biocatalyst is an important indication as to whether the immobilization system is a success. See the first sentence in the last passage of the left column on page 7785.
It would have been obvious to a person of ordinary skill in the art prior to the effective filing date of the instantly claimed invention to coimmobilize cellulase and β-glucosidase, as suggested by Han, onto the modified PPCS-NPS of Suthiwangcharoen, Han and Chang. One would be motivated to do so because Han suggests that the reusability of a biocatalyst is an important indicator of immobilization. There would be a reasonable expectation of success because Han demonstrates reusing polymer-protein biocatalysts for multiple cycles.
Response to Arguments
Applicant's arguments filed 02/17/2026 have been fully considered but they do not apply to the new grounds of rejection set forth above.
Conclusion
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/LOUISE W HUMPHREY/Supervisory Patent Examiner, Art Unit 1657
/K.C.B./Examiner, Art Unit 1657