Custom selenoprotein production enabled by laboratory evolution of recoded bacterial strains

Incorporation of the rare amino acid selenocysteine to form diselenide bonds can improve stability and function of synthetic peptide therapeutics. However, application of this approach to recombinant proteins has been hampered by heterogeneous incorporation, low selenoprotein yields, and poor fitness of bacterial producer strains. We report the evolution of recoded Escherichia coli strains with improved fitness that are superior hosts for recombinant selenoprotein production. We apply an engineered β-lactamase containing an essential diselenide bond to enforce selenocysteine dependence during continuous evolution of recoded E. coli strains. Evolved strains maintain an expanded genetic code indefinitely. We engineer a fluorescent reporter to quantify selenocysteine incorporation in vivo and show complete decoding of UAG codons as selenocysteine. Replacement of native, labile disulfide bonds in antibody fragments with diselenide bonds vastly improves resistance to reducing conditions. Highly seleno-competent bacterial strains enable industrial-scale selenoprotein expression and unique diselenide architecture, advancing our ability to customize the selenoproteome.

[1]  George Georgiou,et al.  Fine-tuning citrate synthase flux potentiates and refines metabolic innovation in the Lenski evolution experiment , 2015, eLife.

[2]  S. Buchwald,et al.  An Umpolung Approach for the Chemoselective Arylation of Selenocysteine in Unprotected Peptides , 2015, Journal of the American Chemical Society.

[3]  A. Talhami,et al.  Accessing human selenoproteins through chemical protein synthesis , 2016, Chemical science.

[4]  Michael T. Green,et al.  Characterization of a selenocysteine-ligated P450 compound I reveals direct link between electron donation and reactivity. , 2017, Nature chemistry.

[5]  C. Gross,et al.  Global analysis of translation termination in E. coli , 2017, PLoS genetics.

[6]  The Long D-stem of the Selenocysteine tRNA Provides Resilience at the Expense of Maximal Function , 2013, The Journal of Biological Chemistry.

[7]  L. Ruddock,et al.  Systematic screening of soluble expression of antibody fragments in the cytoplasm of E. coli , 2016, Microbial Cell Factories.

[8]  S. Dübel,et al.  Isolation of a human-like antibody fragment (scFv) that neutralizes ricin biological activity , 2009, BMC biotechnology.

[9]  H. Scheer,et al.  Biliprotein maturation: the chromophore attachment , 2008, Molecular microbiology.

[10]  A. Kraj,et al.  A novel electrochemical method for efficient reduction of disulfide bonds in peptides and proteins prior to MS detection , 2013, Analytical and Bioanalytical Chemistry.

[11]  Michael Nilsson,et al.  Glutamine is incorporated at the nonsense codons UAG and UAA in a suppressor-free Escherichia coli strain. , 2003, Biochimica et biophysica acta.

[12]  Aditya M. Kunjapur,et al.  Long-term adaptive evolution of genomically recoded Escherichia coli , 2017, bioRxiv.

[13]  Jingyan Wei,et al.  Characterization and structural analysis of human selenium-dependent glutathione peroxidase 4 mutant expressed in Escherichia coli. , 2014, Free radical biology & medicine.

[14]  D. Hilvert,et al.  Strategic use of non-native diselenide bridges to steer oxidative protein folding. , 2012, Angewandte Chemie.

[15]  H. Dewald,et al.  Electrochemistry-assisted top-down characterization of disulfide-containing proteins. , 2012, Analytical chemistry.

[16]  T. Stadtman,et al.  Direct detection of potential selenium delivery proteins by using an Escherichia coli strain unable to incorporate selenium from selenite into proteins , 2002, Proceedings of the National Academy of Sciences of the United States of America.

[17]  D. Craik,et al.  α-Selenoconotoxins, a New Class of Potent α7 Neuronal Nicotinic Receptor Antagonists* , 2006, Journal of Biological Chemistry.

[18]  A. Böck,et al.  The many levels of control on bacterial selenoprotein synthesis. , 2009, Biochimica et biophysica acta.

[19]  Jared B Shaw,et al.  Complete protein characterization using top-down mass spectrometry and ultraviolet photodissociation. , 2013, Journal of the American Chemical Society.

[20]  D. Yoshikami,et al.  Integrated oxidative folding of cysteine/selenocysteine containing peptides: improving chemical synthesis of conotoxins. , 2009, Angewandte Chemie.

[21]  Johannes Buchner,et al.  Evolution of Escherichia coli for Growth at High Temperatures* , 2010, The Journal of Biological Chemistry.

[22]  Peter G. Schultz,et al.  Genomically Recoded Organisms Expand Biological Functions , 2013, Science.

[23]  Roger Y Tsien,et al.  A far-red fluorescent protein evolved from a cyanobacterial phycobiliprotein , 2016, Nature Methods.

[24]  R. Lewis,et al.  Modulating oxytocin activity and plasma stability by disulfide bond engineering. , 2010, Journal of medicinal chemistry.

[25]  Jingyan Wei,et al.  Efficient Expression of Glutathione Peroxidase with Chimeric tRNA in Amber-less Escherichia coli. , 2017, ACS synthetic biology.

[26]  David E. Clemmer,et al.  Disulfide-Intact and -Reduced Lysozyme in the Gas Phase: Conformations and Pathways of Folding and Unfolding , 1997 .

[27]  Jeffrey E. Barrick,et al.  Genomic Analysis of a Key Innovation in an Experimental E. coli Population , 2012, Nature.

[28]  R. Hondal Using chemical approaches to study selenoproteins-focus on thioredoxin reductases. , 2009, Biochimica et biophysica acta.

[29]  A. Ellington,et al.  Exquisite allele discrimination by toehold hairpin primers , 2014, Nucleic acids research.

[30]  J. Vogel,et al.  β-lactam antibiotics promote bacterial mutagenesis via an RpoS-mediated reduction in replication fidelity , 2013, Nature Communications.

[31]  A. Böck,et al.  High-level expression in Escherichia coli of selenocysteine-containing rat thioredoxin reductase utilizing gene fusions with engineered bacterial-type SECIS elements and co-expression with the selA, selB and selC genes. , 1999, Journal of molecular biology.

[32]  L. Mora,et al.  Methylation of Bacterial Release Factors RF1 and RF2 Is Required for Normal Translation Termination in Vivo* , 2007, Journal of Biological Chemistry.

[33]  D. Craik,et al.  Alpha-selenoconotoxins, a new class of potent alpha7 neuronal nicotinic receptor antagonists. , 2006, The Journal of biological chemistry.

[34]  D. Hilvert,et al.  Kinetic consequences of introducing a proximal selenocysteine ligand into cytochrome P450cam. , 2015, Biochemistry.

[35]  Farren J. Isaacs,et al.  Recoded organisms engineered to depend on synthetic amino acids , 2015, Nature.

[36]  A. Böck,et al.  Dynamics and efficiency in vivo of UGA‐directed selenocysteine insertion at the ribosome , 1999, The EMBO journal.

[37]  Ryo Takeuchi,et al.  Biocontainment of genetically modified organisms by synthetic protein design , 2015, Nature.

[38]  Andrew D Ellington,et al.  Addicting diverse bacteria to a noncanonical amino acid. , 2016, Nature chemical biology.

[39]  Dieter Söll,et al.  Evolution of translation machinery in recoded bacteria enables multi-site incorporation of nonstandard amino acids , 2015, Nature Biotechnology.

[40]  Daniel B. Goodman,et al.  Optimizing complex phenotypes through model-guided multiplex genome engineering , 2016, Genome Biology.

[41]  T. Palzkill,et al.  Amino Acid Sequence Requirements at Residues 69 and 238 for the SME-1 β-Lactamase To Confer Resistance to β-Lactam Antibiotics , 2003, Antimicrobial Agents and Chemotherapy.

[42]  Elias S. J. Arnér,et al.  Selenocysteine Insertion at a Predefined UAG Codon in a Release Factor 1 (RF1)-depleted Escherichia coli Host Strain Bypasses Species Barriers in Recombinant Selenoprotein Translation* , 2017, Journal of Biological Chemistry.

[43]  O. Rackham,et al.  Engineered rRNA enhances the efficiency of selenocysteine incorporation during translation. , 2013, Journal of the American Chemical Society.

[44]  A. Ellington,et al.  Evolving tRNA(Sec) for efficient canonical incorporation of selenocysteine. , 2015, Journal of the American Chemical Society.

[45]  Farren J. Isaacs,et al.  Programming cells by multiplex genome engineering and accelerated evolution , 2009, Nature.

[46]  Dongbin Zhao,et al.  High throughput screening of disulfide‐containing proteins in a complex mixture , 2013, Proteomics.

[47]  M. Iwaoka,et al.  Preparation of Selenoinsulin as a Long-Lasting Insulin Analogue. , 2017, Angewandte Chemie.

[48]  Brian Kuhlman,et al.  Structure-based design of supercharged, highly thermoresistant antibodies. , 2012, Chemistry & biology.

[49]  J. C. Layton,et al.  Error-Prone DNA Polymerase IV Is Regulated by the Heat Shock Chaperone GroE in Escherichia coli , 2005, Journal of bacteriology.

[50]  M. Conrad,et al.  Cysteine mutant of mammalian GPx4 rescues cell death induced by disruption of the wild‐type selenoenzyme , 2011, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[51]  C. Emrich,et al.  SHuffle, a novel Escherichia coli protein expression strain capable of correctly folding disulfide bonded proteins in its cytoplasm , 2012, Microbial Cell Factories.