Case Studies

Fab Case Study


Periplasmic expression, multiple secretion leaders:
8 expression plasmids x 31 expression hosts= 248 strains tested in parallel
96 well format, 0.5 ml cultures


case study figure 1

case study figure 2



Protein leads such as Fab fragments are first expressed in hundreds of unique host strains combining elements of the Pfenex toolbox.  Predicting which components of the toolbox will be crucial in successful expression of any given protein cannot be determined from intrinsic information, such as amino acid sequence.  This means that the combination of critical factors is empirical for each individual target protein.  Accordingly, Pfenex Inc has developed a high-throughput screening work process that enables the parallel evaluation of hundreds of unique host strains containing a variety of expression strategies for a specific gene.


When designing a strain engineering and screening strategy, Pfenex scientists utilize an algorithm to evaluate certain attributes of the protein to be expressed, such as the presence of cysteine residues, molecular weight, propensity for proteolytic degradation, and expression performance in other hosts.  In the case study illustrated here it is evident that both host strain phenotype and the choice of secretion leader for the heavy and light components of the Fab fragment impact the amount and activity of the intact, active Fab.  Further, fermentation scouting and range-finding, varying a number of fermentation parameters (using a Design of Experiments (DOE) approach) has been shown to increase the level of expressed active Fab fragment by between 10 and 20-fold.  These results emphasize that both components — strain engineering and fermentation DOE — can be crucial to reach the desired outcome.

Case Studies, Posters and Presentations

November 2012 • SAFC
Technical Transfer of Fermentation Process

November 2012 • Boehringer Ingelheim
Successful Tech Transfer Proves Compatibility of Pfenex Inc. Technology at Boehringer Ingelheim's Microbial Facility

June 2012
Expression of a self assembling immune adjuvant and antigen targeting fusion protein to accelerate the development of new vaccines for emerging infectious diseases
Mark C. Poznansky
Vaccine and Immunotherapy Center
Massachusetts General Hospital


September 2011
Get There Faster With Pfenex


September 2011
Why Sourcing Makes More Sense


May 2011  PEGS
Boehringer Ingelheim Presents- Expression of an Antibody Fragment Utlizing the Pfēnex Expression Technology™ Platform
George Klima- Head Process Scientist Austria
Boehringer Ingelheim


March 2011 • ACS-BIOT
Expeditious Strain and Fermentation Development for Quality Recombinant Protein Production in Pseudomonas fluorescens
Lawrence Chew- Director, Fermentation Development
Pfenex Inc.


March 2011 • ACS-BIOT
Purification of Vaccine Antigens & Carriers Expressed in Pseudomonas fluorescens
Jerry Ngai- Scientist
Pfenex Inc.


Janauary 2011 • Peptalk
Rapid Production of High Quality Protein Enabled by Pfēnex Expression Technology™
Diane Retallack- Director, Molecular Biology
Pfenex Inc.


Janauary 2011 • Peptalk
Soluble Periplasmic Production of Human Granulocyte Colony-Stimulating Factor (G-CSF) in Pseudomonas fluorescens
Hongfan Jin*, Greg T. Cantin, Steven Maki, Lawrence Chew, Jerry Ngai and Diane M. Retallack- Pfenex Inc.


August 2010 • Recovery of Biologics
Novel Extraction and Purification of an Insoluble Protein without Refolding
Anant Patkar*, Ping-Hua Feng, Keith Haney, Lawrence Chew, Lei Lei Sengchanthalangsy, Greg Cantin, Jeff Allen- Pfenex Inc.