Steitz, Thomas

Many biochemical and biophysical studies of CAP-DNA complexes in solution have demonstrated that CAP induces a sharp bend in DNA upon binding. This was confirmed when the group of Thomas Steitz at Yale University determined the crystal structure of cyclic AMP-DNA complex to 3 A resolution. The CAP molecule comprises two identical polypeptide chains of 209 amino acid residues (Figure 8.24). Each chain is folded into two domains that have separate functions (Figure 8.24b). The larger N-terminal domain binds the allosteric effector molecule, cyclic AMP, and provides all the subunit interactions that form the dimer. The C-terminal domain contains the helix-tum-helix motif that binds DNA. 

Figure 28-6 MolScript ribbon drawing of the CAP dimer bound to DNA with two molecules of the coactivator cAMP bound per monomer. A syw-cAMP molecule is bound to the HTH domain and a loop from the N-terminal domain, while the second awii-cAMP is bound more tightly in the center of the larger N-terminal domain. The DNA sequence for each half site is 5 -ATGTCACATTAATTGCGTTGCGC-3 . From Passner and Steitz.131 Courtesy of Thomas A. Steitz.

Figure 29-4 Structure of 23S-28S ribosomal RNAs. (A) The three-dimensional structure of RNA from the 50S subunit of ribosomes of Halocirculci marismortui. Both the 5S RNA and the six structural domains of the 23S RNA are labeled. Also shown is the backbone structure of protein LI. From Ban et al.17 Courtesy of Thomas A. Steitz. (B) The corresponding structure of the 23S RNA from Thermus thermophilus. Courtesy of Yusupov et al.33a (C) Simplified drawing of the secondary structure of E. coli 23S RNA showing the six domains. The peptidyltransferase loop (see also Fig. 29-14) is labeled. This diagram is customarily presented in two halves, which are here connected by dashed lines. Stem-loop 1, which contains both residues 1 and 2000, is often shown in both halves but here only once. From Merryman et al.78 Similar diagrams for Haloarcula marismortui17 and for the mouse79 reveal a largely conserved structure with nearly identical active sites. (D) Cryo-electron microscopic (Cryo-EM) reconstruction of a 50S subunit of a modified E. coli ribosome. The RNA has been modified genetically to have an...

This small RNA is found in the central protuberance of the 50S ribosomal subunit. See Fig 29-4A. Photocrosslinking using thiouridine-containing 5S RNA suggested a close proximity of U89 (marked by arrow) with nucleotide 2477 of the 23S RNA in the loop end of helix 89 (Fig. 29-4).93 (B) Stereoscopic view of the 5S RNA as observed in ribosomes of Haloarcula marismortui. From Ban et al 7 Courtesy of Thomas A. Steitz. 

Type I ribosomeinactivating protein (RIP)/ polynucleotide aminoglycosidase (PAG) Ribosome structure Masayasu Nomura, Ira Wool, Peter Moore, Thomas Steitz 9.1 A... 

Figure 4.54. Resolution Alfects the Quality of an Image. The effect of resolution on the quality of a reconstructed image is shown by an optical analog of x-ray diffraction (A) a photograph of the Parthenon (B) an optical diffraction pattern of the Parthenon (C and D) images reconstructed from the pattern in part B. More data were used to obtain image D than image C, which accounts for the higher quality of image D. [(A) Courtesy of Dr. Thomas Steitz. (B) Courtesy of Dr. David DeRosier).]...

Figure 16.4. Induced Fit in Hexokinase. As shown in blue, the two lobes of hexokinase are separated in the absence of glucose. The conformation of hexokinase changes markedly on binding glucose, as shown in red. The two lobes of the enzyme come together and surround the substrate. [Courtesy of Dr. Thomas Steitz.]...

Figure 29-4 Structure of 23S-28S ribosomal RNAs. (A) The three-dimensional structure of RNA from the SOS subunit of ribosomes of Haloarcula marismortui. Both the 5S RNA and the six structural domains of the 23S RNA are labeled. Also shown is the backbone structure of protein LI. From Ban rf Courtesy of Thomas A. Steitz. (B) The corresponding structure of...

Figure 29-9 Selected views of aminoacyl-tRNA sjmthetase stmcture and action. (A) Alpha-carbon trace of the type IE. coli glutaminyl-tRNA synthetase. The phosphate backbone of tRNA " is shown in black ATP is shown in the active-site cleft. The canonical dinucleotide fold domain near the N terminus is shaded. Two structural motifs (black), proposed to link the active site with regions of the protein-RNA interface involved in tRNA discrimination, are indicated. The a helix (top) connects tRNA recognition in the minor groove of the acceptor stem with binding of the ribose group of ATP. The large loop (center) connects anticodon recognition by the two P-barrel domains (bottom) with sequences flanking the MSK sequence motif, which interacts with the phosphates of ATP. From Perona et Courtesy of Thomas A. Steitz. (B) The active site...

Ban, Nenad, Poul Nissen, Jeffrey Hansen, Peter B. Moore, and Thomas A. Steitz. The Complete Atomic Structure of the Large Rihosomal Subunit at 2.4 A Resolution. Science 289 (2000) 905-20. This is the first of two consecutive articles on the X-ray structure of the rihosome. 

Venkatraman Ramakrishnan (United States), Thomas A. Steitz (United States), and Ada E. Yonath (Israel) for studies of the structure and function of the ribosome. Ramakrishnan, Steitz, and Yonath are responsible for uncovering the structure and function of the ribosome at the atomic level, and it is for that work that they share this Nobel Prize. They used X-ray crystallography to individually map each atom that makes up the ribosome it consists of hundreds of thousands of atoms The ribosome plays a crucial role in each cell, as it is responsible for the synthesis of proteins. On the basis of their results, these researchers have also developed models showing how antibiotics bind to the ribosome. 

For their studies on the structure and mode of action of ribosomes, Venkatraman Ramakrishnan (Medical Research Council, UK), Thomas Steitz (Yale University, U.S.) and Ada Yonath (Weizmann Institute, Israel) were awarded the 2009 Nobel Prize in Chemistry. 

Venkatraman Ramakrishnan, Thomas A. Steitz, 1953 Hermann Staudinger... 

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