Marc André Elsliger

Structural Genomics of the Thermotoga maritima Proteome Implemented in a High-throughput Structure Determination Pipeline

Structural genomics is emerging as a principal approach to define protein structure–function relationships. To apply this approach on a genomic scale, novel methods and technologies must be developed to determine large numbers of structures. We describe the design and implementation of a high-throughput structural genomics pipeline and its application to the proteome of the thermophilic bacterium Thermotoga maritima. By using this pipeline, we successfully cloned and attempted expression of 1,376 of the predicted 1,877 genes (73%) and have identified crystallization conditions for 432 proteins, comprising 23% of the T. maritima proteome. Representative structures from TM0423 glycerol dehydrogenase and TM0449 thymidylate synthase-complementing protein are presented as examples of final outputs from the pipeline.

Crystal structure of thy1, a thymidylate synthase complementing protein from Thermotoga maritima at 2.25 Å resolution

Peter Kuhn, Scott A. Lesley, Irimpan I. Mathews, Jaume M. Canaves, Linda S. Brinen, Xiaoping Dai, Ashley M. Deacon, Marc A. Elsliger, Said Eshaghi, Ross Floyd, Adam Godzik, Carina Grittini, Slawomir K. Grzechnik, Chittibabu Guda, Keith O. Hodgson, Lukasz Jaroszewski, Cathy Karlak, Heath E. Klock, Eric Koesema, John M. Kovarik, Andreas T. Kreusch, Daniel McMullan, Timothy M. McPhillips, Mark A. Miller, Mitchell Miller, Andrew Morse, Kin Moy, Jie Ouyang, Alyssa Robb, Kevin Rodrigues, Thomas L. Selby, Glen Spraggon, Raymond C. Stevens, Susan S. Taylor, Henry van den Bedem, Jeff Velasquez, Juli Vincent, Xianhong Wang, Bill West, Guenter Wolf, John Wooley, and Ian A. Wilson* The Joint Center for Structural Genomics Stanford Synchrotron Radiation Laboratory, Stanford University, Menlo Park, California The Genomics Institute of Novartis Foundation, San Diego, California The San Diego Supercomputer Center, La Jolla, California The University of California, San Diego, La Jolla, California The Scripps Research Institute, La Jolla, California

Structure of the γ-d-glutamyl-l-diamino acid endopeptidase YkfC from Bacillus cereus in complex with l-Ala-γ-d-Glu: insights into substrate recognition by NlpC/P60 cysteine peptidases

The crystal structure of the highly specific γ-d-glutamyl-l-diamino acid endopeptidase YkfC from Bacillus cereus in complex with l-Ala-γ-d-Glu reveals the structural basis for the substrate specificity of NlpC/P60-family cysteine peptidases.

Crystal Structure of the First Eubacterial Mre11 Nuclease Reveals Novel Features that May Discriminate Substrates During DNA Repair

Mre11 nuclease plays a central role in the repair of cytotoxic and mutagenic DNA double-strand breaks. As X-ray structural information has been available only for the Pyrococcus furiosus enzyme (PfMre11), the conserved and variable features of this nuclease across the domains of life have not been experimentally defined. Our crystal structure and biochemical studies demonstrate that TM1635 from Thermotoga maritima, originally annotated as a putative nuclease, is an Mre11 endo/exonuclease (TmMre11) and the first such structure from eubacteria. TmMre11 and PfMre11 display similar overall structures, despite sequence identity in the twilight zone of only approximately 20%. However, they differ substantially in their DNA-specificity domains and in their dimeric organization. Residues in the nuclease domain are highly conserved, but those in the DNA-specificity domain are not. The structural differences likely affect how Mre11 from different organisms recognize and interact with single-stranded DNA, double-stranded DNA and DNA hairpin structures during DNA repair. The TmMre11 nuclease active site has no bound metal ions, but is conserved in sequence and structure with the exception of a histidine that is important in PfMre11 nuclease activity. Nevertheless, biochemical characterization confirms that TmMre11 possesses both endonuclease and exonuclease activities on single-stranded and double-stranded DNA substrates, respectively.

Crystal structure of an iron-containing 1,3-propanediol dehydrogenase (TM0920) from Thermotoga maritima at 1.3 Å resolution

Robert Schwarzenbacher, Frank von Delft, Jaume M. Canaves, Linda S. Brinen, Xiaoping Dai, Ashley M. Deacon, Marc A. Elsliger, Said Eshaghi, Ross Floyd, Adam Godzik, Carina Grittini, Slawomir K. Grzechnik, Chittibabu Guda, Lukasz Jaroszewski, Cathy Karlak, Heath E. Klock, Eric Koesema, John S. Kovarik, Andreas Kreusch, Peter Kuhn, Scott A. Lesley, Daniel McMullan, Timothy M. McPhillips, Mark A. Miller, Mitchell D. Miller, Andrew Morse, Kin Moy, Jie Ouyang, Rebecca Page, Alyssa Robb, Kevin Rodrigues, Thomas L. Selby, Glen Spraggon, Raymond C. Stevens, Henry van den Bedem, Jeff Velasquez, Juli Vincent, Xianhong Wang, Bill West, Guenter Wolf, Keith O. Hodgson, John Wooley, and Ian A. Wilson* The Joint Center for Structural Genomics, California Stanford Synchrotron Radiation Laboratory, Stanford University, Menlo Park, California The Genomics Institute of the Novartis Research Foundation, San Diego, California The San Diego Supercomputer Center, La Jolla, California The University of California, San Diego, La Jolla, California The Scripps Research Institute, La Jolla, California

Bacterial Pleckstrin Homology Domains: a Prokaryotic Origin for the Ph Domain

Pleckstrin homology (PH) domains have been identified only in eukaryotic proteins to date. We have determined crystal structures for three members of an uncharacterized protein family (Pfam PF08000), which provide compelling evidence for the existence of PH-like domains in bacteria (PHb). The first two structures contain a single PHb domain that forms a dome-shaped, oligomeric ring with C5 symmetry. The third structure has an additional helical hairpin attached at the C-terminus and forms a similar but much larger ring with C12 symmetry. Thus, both molecular assemblies exhibit rare, higher-order, cyclic symmetry but preserve a similar arrangement of their PHb domains, which gives rise to a conserved hydrophilic surface at the intersection of the β-strands of adjacent protomers that likely mediates protein–protein interactions. As a result of these structures, additional families of PHb domains were identified, suggesting that PH domains are much more widespread than originally anticipated. Thus, rather than being a eukaryotic innovation, the PH domain superfamily appears to have existed before prokaryotes and eukaryotes diverged.

Structure of a membrane-attack complex/perforin (MACPF) family protein from the human gut symbiont Bacteroides thetaiotaomicron.

The crystal structure of a novel MACPF protein, which may play a role in the adaptation of commensal bacteria to host environments in the human gut, was determined and analyzed.

Crystal structure of O-acetylserine sulfhydrylase (TM0665) from Thermotoga maritima at 1.8 Å resolution

Andreas Heine, Jaume M. Canaves, Frank von Delft, Linda S. Brinen, Xiaoping Dai, Ashley M. Deacon, Marc A. Elsliger, Said Eshaghi, Ross Floyd, Adam Godzik, Carina Grittini, Slawomir K. Grzechnik, Chittibabu Guda, Lukasz Jaroszewski, Cathy Karlak, Heath E. Klock, Eric Koesema, John S. Kovarik, Andreas Kreusch, Peter Kuhn, Scott A. Lesley, Daniel McMullan, Timothy M. McPhillips, Mark A. Miller, Mitchell D. Miller, Andrew Morse, Kin Moy, Jie Ouyang, Rebecca Page, Alyssa Robb, Kevin Rodrigues, Robert Schwarzenbacher, Thomas L. Selby, Glen Spraggon, Raymond C. Stevens, Henry van den Bedem, Jeff Velasquez, Juli Vincent, Xianhong Wang, Bill West, Guenter Wolf, Keith O. Hodgson, John Wooley, and Ian A. Wilson* The Joint Center for Structural Genomics, Stanford Synchrotron Radiation Laboratory, Stanford University, Menlo Park, California The Genomics Institute of the Novartis Research Foundation, San Diego, California The San Diego Supercomputer Center, La Jolla, California The University of California, San Diego, La Jolla, California The Scripps Research Institute, La Jolla, California

Comparison of NMR and crystal structures highlights conformational isomerism in protein active sites

Tools for systematic comparisons of NMR and crystal structures developed by the JCSG were applied to two proteins with known functions: the T. maritima anti-σ factor antagonist TM1081 and the mouse γ-glutamylamine cyclotransferase A2LD1 (gi:13879369). In an attempt to exploit the complementarity of crystal and NMR data, the combined use of the two structure-determination techniques was explored for the initial steps in the challenge of searching proteins of unknown functions for putative active sites.

Structure-based discovery of NANOG variant with enhanced properties to promote self-renewal and reprogramming of pluripotent stem cells

Significance Maintenance and reprogramming of pluripotency are among the most important issues in stem cell biology and regenerative medicine. Pluripotency is governed by several key transcription factors regulating transcription of other factors. Among these, regulation of OCT4 transcription by NANOG (from Irish myth-ology Tír na nÓg) is a critical interaction. We present here the crystal structure of human NANOG homeodomain in complex with the OCT4 promoter DNA and, through a series of ration-ally designed mutations, we identify key functional residues in the protein–DNA interaction, protein stability, and maintenance of mouse ESC self-renewal. Furthermore, we describe a mutation, NANOG L122A, which enhances DNA binding affinity, protein stability, mouse ESC self-renewal, and reprogramming into ground state from primed state pluripotency. NANOG (from Irish mythology Tír na nÓg) transcription factor plays a central role in maintaining pluripotency, cooperating with OCT4 (also known as POU5F1 or OCT3/4), SOX2, and other pluripotency factors. Although the physiological roles of the NANOG protein have been extensively explored, biochemical and biophysical properties in relation to its structural analysis are poorly understood. Here we determined the crystal structure of the human NANOG homeodomain (hNANOG HD) bound to an OCT4 promoter DNA, which revealed amino acid residues involved in DNA recognition that are likely to be functionally important. We generated a series of hNANOG HD alanine substitution mutants based on the protein–DNA interaction and evolutionary conservation and determined their biological activities. Some mutant proteins were less stable, resulting in loss or decreased affinity for DNA binding. Overexpression of the orthologous mouse NANOG (mNANOG) mutants failed to maintain self-renewal of mouse embryonic stem cells without leukemia inhibitory factor. These results suggest that these residues are critical for NANOG transcriptional activity. Interestingly, one mutant, hNANOG L122A, conversely enhanced protein stability and DNA-binding affinity. The mNANOG L122A, when overexpressed in mouse embryonic stem cells, maintained their expression of self-renewal markers even when retinoic acid was added to forcibly drive differentiation. When overexpressed in epiblast stem cells or human induced pluripotent stem cells, the L122A mutants enhanced reprogramming into ground-state pluripotency. These findings demonstrate that structural and biophysical information on key transcriptional factors provides insights into the manipulation of stem cell behaviors and a framework for rational protein engineering.