Distinguished Fellow

Steven Benner

Education

• BS in Molecular Biophysics and Biochemistry. Yale University (1976)
• MS in Molecular Biophysics and Biochemistry. Yale University (1976)
• PhD in Chemistry. Harvard University (1979)

Research summary

1. Initiated synthetic biology as a field. The Benner group was the first to synthesize a gene for an enzyme, and used organic synthesis to prepare the first artificial genetic systems. These systems have been used to direct the synthesis of artificial proteins having unnatural amino acids, in FDA-approved clinical assays for HIV, hepatitis B and hepatitis C that improves the medical care of over 400,000 patients annually, and to support the first artificial chemical system capable of Darwinian evolution.
2. Invented dynamic combinatorial chemistry, combining ideas from molecular evolution, enzymology, analytical chemistry, and organic chemistry to generate a strategy to discover small molecule therapeutic leads. A German company, Alantos, is today using this technology to develop drug leads.
3. Established paleomolecular biology, where researchers resurrect ancestral proteins from extinct organisms for study in the laboratory, The strategy allows scientists to connect chemistry to function in biology, which is defined by an organism's fitness in a complex and changing environment.
4. Helped found evolutionary bioinformatics, in 1991, launched one of the first web-based bioinformatics servers with Gaston Gonnet, generated the first naturally organized protein sequence databases, and helped develop the MasterCatalog that generated ca. $4 million in sales. This work also supported the first exhaustive matching of a modern protein sequence database, the first convincing tools to predict structure in proteins from sequence data, strategies to detect distant homologs using structure prediction, and "post-genomic" tools to detect changing protein function.

Awards

• National Science Foundation Graduate Fellow
• Junior Fellowship, Harvard Society of Fellows
• Dreyfus Award for Young Faculty, 1982
• Searle Scholar, 1984-86
• Sloan Foundation Fellow, 1984-86
• Anniversary Prize, Federation of European Biochemical Societies, 1993
• Nolan Summer Award, 1998
• Arun Gunthikonda Memorial Award, 1998
• Townes R. Leigh Commemorative Professor, 1999
• B. R. Baker Award, 2001
• Sigma Xi Senior Faculty Award 2005

Recent Publications

Recognition of an expanded genetic alphabet by type-II restriction endonucleases and their application to analyze polymerase fidelity.
Chen, F; Yang, ZY; Yan, M; Alvarado, JB; Wang, G; Benner, SA
Nucl. Acids Res. 39 (9) 3949-3961 (2011)
<Abstract>

To explore the possibility of using restriction enzymes in a synthetic biology based on artificially expanded genetic information systems (AEGIS), 24 type-II restriction endonucleases (REases) were challenged to digest DNA duplexes containing recognition sites where individual Cs and Gs were replaced by the AEGIS nucleotides Z and P [respectively, 6-amino-5-nitro-3-(1'-?-d-2'-deoxyribofuranosyl)-2(1H)-pyridone and 2-amino-8-(1'-?-d-2'-deoxyribofuranosyl)-imidazo[1,2-a]-1,3,5-triazin-4(8H)-one]. These AEGIS nucleotides implement complementary hydrogen bond donor-donor-acceptor and acceptor-acceptor-donor patterns. Results allowed us to classify type-II REases into five groups based on their performance, and to infer some specifics of their interactions with functional groups in the major and minor grooves of the target DNA. For three enzymes among these 24 where crystal structures are available (BcnI, EcoO109I and NotI), these interactions were modeled. Further, we applied a type-II REase to quantitate the fidelity polymerases challenged to maintain in a DNA duplex C:G, T:A and Z:P pairs through repetitive PCR cycles. This work thus adds tools that are able to manipulate this expanded genetic alphabet in vitro, provides some structural insights into the working of restriction enzymes, and offers some preliminary data needed to take the next step in synthetic biology to use an artificial genetic system inside of living bacterial cells.

Synthetic Biology, Tinkering Biology, and Artificial Biology: A Perspective from Chemistry
Benner, SA; Chen, F; Yang, ZY
Chemical Synthetic Biology , ed. Pier Luigi Luisi and Cristiano Chiarabelli , Wiley 69-106 (2011)

Setting the Stage: The History, Chemistry, and Geobiology behind RNA
Benner, SA; Kim, HJ; Yang, ZY
RNA Worlds: From Life's Origins to Diversity in Gene Regulation , ed. John F. Atkins, Raymond F. Gesteland, Thomas R. Cech , Cold Spring Harbor Laboratory Press 7-19 (2011)

Amplification, Mutation, and Sequencing of a Six-Letter Synthetic Genetic System
Yang, Z; Chen, F; Alvarado, JB; Benner, SA
J. Am. Chem. Soc. 133 (38) 15105-15112 (2011) dx.doi.org/10.1021/ja204910n
<Abstract>

The next goals in the development of a synthetic biology that uses artificial genetic systems will require chemistry-
biology combinations that allow the amplification of DNA containing any number of sequential and nonsequential nonstandard nucleotides. This amplification must ensure that the nonstandard nucleotides are not unidirectionally lost during PCR amplification (unidirectional loss would cause the artificial system to revert to an all-natural genetic system). Further, technology is needed to sequence artificial genetic DNA molecules. The work reported here meets all three of these goals for a sixletter artificially expanded genetic information system (AEGIS) that comprises four standard nucleotides (G, A, C, and T) and two additional nonstandard nucleotides (Z and P). We report polymerases and PCR conditions that amplify a wide range of GACTZP DNA sequences having multiple consecutive unnatural synthetic genetic components with low (0.2% per theoretical cycle) levels of mutation. We demonstrate that residual mutation processes both introduce and remove unnatural nucleotides, allowing the artificial genetic system to evolve as such, rather than revert to a wholly natural system. We then show that mechanisms for these residual mutation processes can be exploited in a strategy to sequence "six-letter" GACTZP DNA. These are all not yet reported for any other synthetic genetic system.

Labeled nucleoside triphosphates with reversibly terminating aminoalkoxyl groups
Hutter, D; Kim, MJ; Karalkar, N; Leal, NA; Chen, F; Guggenheim, E; Visalakshi, V; Olejnik, J; Gordon, S; Benner, SA
Nuc. Nuc. Nuc. acids 29 (11) 879-895 (2010)
<Abstract>

Nucleoside triphosphates having a 3'-ONH(2) blocking group have been prepared with and without fluorescent tags on their nucleobases. DNA polymerases were identified that accepted these, adding a single nucleotide to the 3'-end of a primer in a template-directed extension reaction that then stops. Nitrite chemistry was developed to cleave the 3'-ONH(2) group under mild conditions to allow continued primer extension. Extension-cleavage-extension cycles in solution were demonstrated with untagged nucleotides and mixtures of tagged and untagged nucleotides. Multiple extension-cleavage-extension cycles were demonstrated on an Intelligent Bio-Systems Sequencer, showing the potential of the 3'-ONH(2) blocking group in "next generation sequencing."

Expanded Genetic Alphabets in the Polymerase Chain Reaction
Yang, ZY; Chen, F; Chamberlin, SG; Benner, SA
Angew. Chem. Int. Ed. 49 (1) 177-180 (2010)

Artificial Genetic Systems: Self-Avoiding DNA in PCR and Multiplexed PCR
Hoshika, S; Chen, F; Leal, NA; Benner, SA
Angew. Chem. Int. Ed. 49 (32) 5554-5557 (2010)

Reconstructed evolutionary adaptive paths give polymerases accepting reversible terminators for sequencing and SNP detection
Chen, F; Gaucher, EA; Leal, NA; Hutter, D; Havemann, SA; Govindarajan, S; Ortlund, EA; Benner, SA
Proc. Natl. Acad. Sci. USA 107 (5) 1948-1953 (2010)

Chemistry, Life, and the Search for Aliens
Benner, SA
Proc. SPIE 7819 (10) 1-12 (2010)
<Abstract>

While "life" may universally be a self-sustaining chemical system capable of Darwinian evolution, alien life may be quite different in its chemistry from the terran life that we know here on Earth. In this case, it will be difficult to recognize, especially if it has not advanced beyond the single cell life forms that have dominated much of the terran biosphere. This review summarizes what we might infer from general physical and chemical law about how such "weird" life might be structured, what solvents other than water it might inhabit, what genetic molecules it might contain, and what metabolism it might exploit.

Interview with Steven Benner
Impey, C; Benner, SA
Talking about Life: Conversations on Astrobiology , ed. Chris Impey , Cambridge University Press 58-68 (2010)

(View all publications by Steven Benner)