EricWaltersResume2016

Eric Walters 510-432-2529 [email protected] 25200 Carlos Bee #199 , Hayward, Ca 94542

SKILLS/EXPERIENCE

Versatile published scientist excelling in independent research and development- I enjoy intellectual and scientific challenges. I bring over twenty years of diverse and deep experience in the various aspects of protein science including purification and characterization (HPLC, MALDI-MS, LC-MS)

HPLC/UPLC Method Development: Developed SEC (standard and organic

phase), Cation Exchange, Reverse Phase (intact and reduced) for Monoclonal antibodies and hybrid fusion antibodies proteins for characterization and quality monitoring. Created several novel HPLC methods for important protein components involved in biosynthesis (Cell Free) of biopharmaceuticals.

Protein purification methods design and optimization, ten years of hands on purification experience with diverse proteins purified from CHO, yeast, bacteria, and

plants via gravity flow and FPLC (AKTA) columns. Expressed, harvested, purified and characterized two viral proteins (rNA). Developed one step purification-small scale for EBVgp350. Created novel quantitative and qualitative HPLC assay for non-purified EBVgp350 (TDR in progress) Involved in all aspects of HA expression, purification, and quality assessment.

Viral proteins/Monoclonal Antibodies: Setting up panel of analytical techniques for quantifying and characterization of product quality for Monoclonal Antibodies (size, intactness, charge isoforms, glycan profiling, protein A titer analysis. Responsible for analysis and structural characterization of purification fractions by HPLC, SDS PAGE (Electrophoresis), ELISA, Western blotting, Mammalian Cell Culture (CHO), Flu

Virus surface proteins (HA/NA), Plasmid Purification (GigaPrep). Currently developing purification for untagged CMVgB and developing analytical techniques to assist cell culture development (EBVgp350, RSV) at Medimmune- and to determine quality and characteristics of various viral receptor proteins (RSV, EBVgp350, etc).

Monoclonal Antibodies: Nine years of assay development and characterization of monoclonal antibodies proteins in research and cGMP/GLP modes of operation.

Familiar with Softmax, and various HPLC software packages, Excel used for data analysis, and Word for report generation. Fast learner and excellent independent thinker. Five years training in cGMP and GLP.

Developed novel enzyme assays to determine activity and specific activity of purified enzymes. Enzyme mode of action and kinetics determinations from purified fractions (published), Monoclonal Antibody Analytical Development, structure

analysis (peptide mapping and intact mass), HPLC methods development and qualification (reverse phase, normal phase, size exclusion, HIC, ion exchange, affinity), MALDI, LC-MS (mass spectrometry), test method writing, technical development reports and SOP writing, peptide mapping, degradation pathway characterization. Working knowledge of cGMP’s related to bio-pharmaceutical development

Protein purification: well versed in native and tagged purification-from cell lysate

to homogeneity via column chromatography and ancillary methods including ultra

mailto:[email protected]


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filtration and concentration.

Enzyme assay development (including pathway based assays) for small molecule screening, protein conjugation chemistry, biochip multiplexed assay development, ELISA, active enzyme purification, FPLC, low pressure column chromatography,

electrophoresis, UV/Vis spectrophotometry, Biacore, scientific brainstorming and trouble shooting. Functional and quantitative enyzyme assay development, peptide mapping, enzyme kinetics (Vmax, Ki, etc), ELISA (plate and bead based).

Instrumentation (including but not limited to): HPLC, MALDI-Mass Spec, FPLC, spectrophotomers, spectrofluorometers, scintillation counters, centrifuges, electrophoresis (PAGE, Western blots), GC, robotics (Biomek), liquid handling, BiaCore, fluorescence microscopes.

SUMMARY Versatile scientist with over twenty years of bench experience. Strong track record of working in a cross-functional environment to develop interdisciplinary solutions.

Excellent writing, verbal, and computer skills (MS Word, Excel, and Powerpoint).

EXPERIENCE 03/2012- 10/2015 Sutro BioPharma, South San Francisco, CA. Scientist/Senior Research Associate (Contract/Permanent): Analytical Development:

hired to introduce and run HPLC methods for quantifying and analyzing quality attributes for Moloclonal Antibodies (mAbs) including SEC, Cation Exchange, and Protein A, and Reverse Phase HPLC for several mAb’s. Developed pre-HPLC flocculation and clarification methods for Cell Free (modified bacterial lysate)

produced Monoclonal antibodies. Created HPLC analytical methods (novel) for various biosynthetic molecules in the Cell Free mixture and fusion proteins. Developed Mass Spec (M/S) compatible SEC methods. Advised and assisted Research on developing HPLC methods for new proteins. Wrote formal SOP’s and qualification plans for various HPLC Methods.

02/2011- 12/22/2011 Medimmune, Santa Clara, CA. (contract)

Associate Scientist II: Cell culture Development: Harvest, Purification and analysis of 4 recombinant Flu Virus surface proteins- HA (Florida,Perth,California,Brisbane). Carried out entire process (expression to purification and quality) of 2 NA proteins.



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Developing analytical methods to characterize purity and quality parameters for EBVgp350, HA, soluble F, and CMVgB. Setting up panel of quality determining assays for Monoclonal Antibodies (IgG) including intactness, glycan profiling, charge

isoforms, Protein A titer and others. Maintaining Mammalian (CHO) Cell Cultures, Bacterial Cell Cultures, GigaPreps (Plasmid Purification) etc.

11/2005- 11/2010 Xoma, LLC , Berkeley, CA.

Senior Research Associate (Associate Scientist): Analytical Development: Responsible for HPLC Assay Development and analysis of cell harvests and (purification) column fractions for mammalian and bacterial Monoclonal Antibodies and Fab’s. Developed test methods for determining Fab titers from bacterial broths and column fractions

including HPLC column, conditions and pre-analysis sample treatment Responsible for the characterization of numerous Monoclonal Antibodies produced at Xoma (charge isoforms, post-translational modifications). Developed/introduced glycan (glycosylation) profiling and antibody peptide mapping techniques utilizing MALDI-

TOF as ancillary methodologies for CE and HPLC-MS. Developed HPLC and Mass Spec methodologies to characterize hinge region degradation pathway. Coordinated dialysis, and outside contractor AAA analysis. Monoclonal Antibody Analytical development and qualification for GMP use in support of Phase I and II Clinical

Studies

6/2005-ending 10/20/05 Chiron (Biopharma) Berkeley, CA. :

Analytical Development Protein Structure and Analysis Group (Contract/Temp):

Recombinant Proteins MALDI: introduced and developed protein purification methodology for detergent removal and characterization of interleukin (IL-2) biotinylation. MALDI mass

determinations for intact and deglycosylated proteins (anti-HIV), peptide mapping of proteins. Improved protein deglycosylation, digestion, and subsequent SEC purification. HPLC/mass spectrometry (ESI) Software (Mass Lynx, Protein Lynx, and Gpmaw) used for sequence verification. Empower for (HPLC) reverse phase HPLC method set up. Assisted with PAGE (electrophoresis) GMP assay validation for intact

cell lysate quantification of protein of interest.

4/2003–11/2004 Trellis Biosciences, South San Francisco, CA.

Senior Research Assoc / Scientist

Designed and conducted experiments in the development of fluorescent nanobead –

antibody protein conjugation chemistry for cytokine identification and localization (Intracellular and Cell Surface Staining projects).

Evaluated several combinations of modified styrene surfaces and modified target functional groups for direct and indirect coupling after oxidative or reductive



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chemistry. Conventional and bead ELISA development.

Testing of proprietary software developed for digital imaging and quantification of multihued fluorescent nano-particles

Evaluated methods to improve biocompatibility of nanobeads involving covalent coupling of hydrophilic surfaces

3/2000–12/2002 Zyomyx, Inc., Hayward, CA.

Senior Research Associate/Associate Scientist

Performed experiments in the development of protein biochips.

Contributed significant improvements in assay development and process development for cytokine micro array biochip

Improved sensitivity of cytokine assay fourfold (4X)

Developed novel methods to stabilize tethered proteases on microchip surfaces (for screening Peptides)

1999–1999 Oread, Inc. Palo Alto, CA.

Chemist II

Evaluated pharmaceuticals for dissolution, particle size and purity using HPLC and particle sizer in accordance with GMP and SOP

1991–1998 Sandoz/Novartis, Inc Palo Alto, CA.

Biochemist II (proteins, metabolites) 8 years experience

Published first native protein purification (enzyme) and kinetic characterization of Adenylosuccinate synthetase and Inhibition by Phosphohydantocidin in plants

Characterized mechanism of Inhibition of Enzymes by small molecules from libraries and synthesis by in-house chemists

Purified to homogeneity and kinetically characterized various Proteins from crude native source materials and recombinant sources

Developed and worked with numerous spectrophotometric, fluorimetric, colorimetric and HPLC enzyme assays

Designed multiple enzyme pathway assays, including substrate synthesis, both chemical and enzymatic (see patent)

Implemented, developed, and defended (in scientific project meetings) a biochemical target site involving several enzymes in a biosynthetic pathway. From literature search

to design of required enzyme assays and substrate synthesis (in collaboration with the chemistry department). Sought out collaborators and justified creation of the new project involving multiple departments.

Developed numerous HPLC methods for enzyme assay and metabolite assay (RP, HIC, Ion exchange/pairing).



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1988–1991 Beckman Instruments Palo Alto, CA

Senior Applications Scientist

Developed new ELISA applications for robotic laboratory workstations (Biomek and GenELISA)

Provided Tech support for robotic workstation-software/hardware, both telephone and in customer laboratories

Wrote technical publications for robotic workstation

Partnered with the Marketing, Sales, Engineering, and Software departments to develop new uses for the laboratory robotics

Delivered presentations to university and commercial laboratories on the use of the robotics systems

Worked with Engineering and Software departments to troubleshoot (alpha and beta testing) new software and hardware, and to develop new attachments, accessories for

the robotic workstation

1985–1988 Cooper Biomedical, Mountain View, CA

Research Assoc I, II, III (Process Development)

Assisted in development of protein purification schemes, analyzed fractions with ELISA

Trained/ assisted production purification team in scale up in pilot plant

Performed small batch protein (1L) production experiments and scale up to 100L

Performed QC for recombinant protein pilot plant lots

EDUCATION

1984 University of California Santa Cruz, CA Bachelors in Biochemistry and Molecular Biology



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PUBLICATIONS

Eric W. Walters, Shy-Fu Lee, Thierry Niderman, Paul Bernasconi, Mani V. Subramanian, and Daniel L. Siehl Adenylosuccinate Synthetase from Maize, Purification, Properties, and Mechanism of Inhibition by 5’-Phosphohydantocidin, Plant Physiol. (1997) 114:549-555

Paul Bernasconi, Eric W. Walters, Alison R. Woodworth, Daniel L. Siehl, Tracey E. Stone, and Mani V. Subramanian Functional Expression of Arabidopsis thaliana Anthranilate Synthase Subunit 1 in Escherichia coli, Plant Physiol. (1994)106: 353-358

Daniel L. Siehl, Mani V. Subramanian, Eric W. Walters, Shy-Fu Lee, Richard J. Anderson, and Ann G. Toschi Adenylosuccinate Synthetase: Site of Action of Hydantocidin, a Microbial Phytotoxin Plant Physiol. (1996) 110: 753-758

Daniel L. Siehl, Mani V. Subramanian, Eric W. Walters, Jonathan H. Blanding, Thierry Niderman, Christian Weinmann Evaluating anthranilate synthase as a herbicide target Weed Science, 45: 628-633. 1997

Sandra Brunn, Mani V. Subramanian, Eric Walters, Bhavesh Patel, Jeffrey Reagan Biochemical Characterization of Auxin Transport Protein Using Phytotropins ACS

Symposium Series 557, Bioregulators for Crop Protection and Pest Control, Paul Hedin, Editor, 202-211, 1994

The Automation of Three Clinically Important ELISAs With The GenELISA™ V2.1 System, Eric Walters, Senior Applications Chemist, Beckman Instruments, Inc., Fullerton, CA 92634 Beckman Product Number T-1709-ROB-91-5

Poster: Development and Qualification of an HPLC Oxidation Assay for Botulinum

Neurotoxin Serotype A Antibody Mixture Erica Cleary, Eric Walters, Rahima Danishmand, Glen Teshima, Vafa Lahidji, Joel Freeberg, and Milan Tomic, XOMA (US) LLC, 2910 Seventh Street, Berkeley, CA 94710

Poster: Development of Quantitative EBV gp 350 HPLC Assay for Cell Line

Development : Eric Walters*, Ramarao Vepechedu, Medimmune, CCPD, Cell Culture Development, Santa Clara, CA

POSTER

PATENT

Methods to Screen Herbicidal Compounds Utilizing AIR Synthetase from

Arabidopsis thaliana Eric Ward, David Guyer, Sharon Potter, Venketeswaran Subramanian, Eric Walters W099/67402 June 22, 1999


Documents

EricWaltersResume2016