ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Articles  (95)
  • Crystallography, X-Ray  (95)
  • 2005-2009  (95)
  • 1940-1944
  • Natural Sciences in General  (95)
  • Physics  (95)
Collection
  • Articles  (95)
Years
Year
Topic
  • 1
    Publication Date: 2008-03-08
    Description: The creation of enzymes capable of catalyzing any desired chemical reaction is a grand challenge for computational protein design. Using new algorithms that rely on hashing techniques to construct active sites for multistep reactions, we designed retro-aldolases that use four different catalytic motifs to catalyze the breaking of a carbon-carbon bond in a nonnatural substrate. Of the 72 designs that were experimentally characterized, 32, spanning a range of protein folds, had detectable retro-aldolase activity. Designs that used an explicit water molecule to mediate proton shuffling were significantly more successful, with rate accelerations of up to four orders of magnitude and multiple turnovers, than those involving charged side-chain networks. The atomic accuracy of the design process was confirmed by the x-ray crystal structure of active designs embedded in two protein scaffolds, both of which were nearly superimposable on the design model.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3431203/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3431203/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Jiang, Lin -- Althoff, Eric A -- Clemente, Fernando R -- Doyle, Lindsey -- Rothlisberger, Daniela -- Zanghellini, Alexandre -- Gallaher, Jasmine L -- Betker, Jamie L -- Tanaka, Fujie -- Barbas, Carlos F 3rd -- Hilvert, Donald -- Houk, Kendall N -- Stoddard, Barry L -- Baker, David -- R01 CA097328/CA/NCI NIH HHS/ -- R01 GM049857/GM/NIGMS NIH HHS/ -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2008 Mar 7;319(5868):1387-91. doi: 10.1126/science.1152692.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18323453" target="_blank"〉PubMed〈/a〉
    Keywords: Aldehyde-Lyases/*chemistry/metabolism ; *Algorithms ; Binding Sites ; Catalysis ; Catalytic Domain ; Computer Simulation ; Crystallography, X-Ray ; Hydrogen Bonding ; Hydrophobic and Hydrophilic Interactions ; Kinetics ; Models, Molecular ; Protein Conformation ; Protein Engineering
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2009-11-26
    Description: Mutations in the enzyme cytosolic isocitrate dehydrogenase 1 (IDH1) are a common feature of a major subset of primary human brain cancers. These mutations occur at a single amino acid residue of the IDH1 active site, resulting in loss of the enzyme's ability to catalyse conversion of isocitrate to alpha-ketoglutarate. However, only a single copy of the gene is mutated in tumours, raising the possibility that the mutations do not result in a simple loss of function. Here we show that cancer-associated IDH1 mutations result in a new ability of the enzyme to catalyse the NADPH-dependent reduction of alpha-ketoglutarate to R(-)-2-hydroxyglutarate (2HG). Structural studies demonstrate that when arginine 132 is mutated to histidine, residues in the active site are shifted to produce structural changes consistent with reduced oxidative decarboxylation of isocitrate and acquisition of the ability to convert alpha-ketoglutarate to 2HG. Excess accumulation of 2HG has been shown to lead to an elevated risk of malignant brain tumours in patients with inborn errors of 2HG metabolism. Similarly, in human malignant gliomas harbouring IDH1 mutations, we find markedly elevated levels of 2HG. These data demonstrate that the IDH1 mutations result in production of the onco-metabolite 2HG, and indicate that the excess 2HG which accumulates in vivo contributes to the formation and malignant progression of gliomas.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2818760/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2818760/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dang, Lenny -- White, David W -- Gross, Stefan -- Bennett, Bryson D -- Bittinger, Mark A -- Driggers, Edward M -- Fantin, Valeria R -- Jang, Hyun Gyung -- Jin, Shengfang -- Keenan, Marie C -- Marks, Kevin M -- Prins, Robert M -- Ward, Patrick S -- Yen, Katharine E -- Liau, Linda M -- Rabinowitz, Joshua D -- Cantley, Lewis C -- Thompson, Craig B -- Vander Heiden, Matthew G -- Su, Shinsan M -- P01 CA104838/CA/NCI NIH HHS/ -- P01 CA104838-05/CA/NCI NIH HHS/ -- P30 EB009998/EB/NIBIB NIH HHS/ -- R01 CA105463/CA/NCI NIH HHS/ -- R01 CA105463-06/CA/NCI NIH HHS/ -- R21 CA128620/CA/NCI NIH HHS/ -- England -- Nature. 2009 Dec 10;462(7274):739-44. doi: 10.1038/nature08617. Epub .〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Agios Pharmaceuticals, Cambridge, Massachusetts 02139, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19935646" target="_blank"〉PubMed〈/a〉
    Keywords: Arginine/genetics ; Brain Neoplasms/*genetics/*metabolism/pathology ; Catalytic Domain ; Cell Line ; Crystallography, X-Ray ; Disease Progression ; Enzyme Assays ; Glioma/genetics/metabolism/pathology ; Glutarates/*metabolism ; Histidine/genetics/metabolism ; Humans ; Isocitrate Dehydrogenase/*genetics/*metabolism ; Ketoglutaric Acids/metabolism ; Models, Molecular ; Mutant Proteins/*genetics/*metabolism ; Mutation/genetics ; Protein Conformation
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2009-12-08
    Description: The site on HIV-1 gp120 that binds to the CD4 receptor is vulnerable to antibodies. However, most antibodies that interact with this site cannot neutralize HIV-1. To understand the basis of this resistance, we determined co-crystal structures for two poorly neutralizing, CD4-binding site (CD4BS) antibodies, F105 and b13, in complexes with gp120. Both antibodies exhibited approach angles to gp120 similar to those of CD4 and a rare, broadly neutralizing CD4BS antibody, b12. Slight differences in recognition, however, resulted in substantial differences in F105- and b13-bound conformations relative to b12-bound gp120. Modeling and binding experiments revealed these conformations to be poorly compatible with the viral spike. This incompatibility, the consequence of slight differences in CD4BS recognition, renders HIV-1 resistant to all but the most accurately targeted antibodies.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2862588/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2862588/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Chen, Lei -- Kwon, Young Do -- Zhou, Tongqing -- Wu, Xueling -- O'Dell, Sijy -- Cavacini, Lisa -- Hessell, Ann J -- Pancera, Marie -- Tang, Min -- Xu, Ling -- Yang, Zhi-Yong -- Zhang, Mei-Yun -- Arthos, James -- Burton, Dennis R -- Dimitrov, Dimiter S -- Nabel, Gary J -- Posner, Marshall R -- Sodroski, Joseph -- Wyatt, Richard -- Mascola, John R -- Kwong, Peter D -- Z99 AI999999/Intramural NIH HHS/ -- New York, N.Y. -- Science. 2009 Nov 20;326(5956):1123-7. doi: 10.1126/science.1175868.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19965434" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Antibodies, Neutralizing/chemistry/*immunology/metabolism ; Antigens, CD4/chemistry/*metabolism ; Binding Sites ; Binding Sites, Antibody ; Crystallography, X-Ray ; Epitopes ; HIV Antibodies/*chemistry/*immunology/metabolism ; HIV Envelope Protein gp120/*chemistry/*immunology/metabolism ; Hiv-1 ; Humans ; Hydrophobic and Hydrophilic Interactions ; *Immune Evasion ; Models, Molecular ; Molecular Sequence Data ; Peptide Fragments/chemistry/immunology/metabolism ; Protein Conformation
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2009-12-22
    Description: Broken chromosomes arising from DNA double-strand breaks result from endogenous events such as the production of reactive oxygen species during cellular metabolism, as well as from exogenous sources such as ionizing radiation. Left unrepaired or incorrectly repaired they can lead to genomic changes that may result in cell death or cancer. DNA-dependent protein kinase (DNA-PK), a holoenzyme that comprises the DNA-PK catalytic subunit (DNA-PKcs) and the heterodimer Ku70/Ku80, has a major role in non-homologous end joining-the main pathway in mammals used to repair double-strand breaks. DNA-PKcs is a serine/threonine protein kinase comprising a single polypeptide chain of 4,128 amino acids and belonging to the phosphatidylinositol-3-OH kinase (PI(3)K)-related protein family. DNA-PKcs is involved in the sensing and transmission of DNA damage signals to proteins such as p53, setting off events that lead to cell cycle arrest. It phosphorylates a wide range of substrates in vitro, including Ku70/Ku80, which is translocated along DNA. Here we present the crystal structure of human DNA-PKcs at 6.6 A resolution, in which the overall fold is clearly visible, to our knowledge, for the first time. The many alpha-helical HEAT repeats (helix-turn-helix motifs) facilitate bending and allow the polypeptide chain to fold into a hollow circular structure. The carboxy-terminal kinase domain is located on top of this structure, and a small HEAT repeat domain that probably binds DNA is inside. The structure provides a flexible cradle to promote DNA double-strand-break repair.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2811870/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2811870/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sibanda, Bancinyane L -- Chirgadze, Dimitri Y -- Blundell, Tom L -- 079281/Wellcome Trust/United Kingdom -- A3846/Cancer Research UK/United Kingdom -- Wellcome Trust/United Kingdom -- England -- Nature. 2010 Jan 7;463(7277):118-21. doi: 10.1038/nature08648. Epub 2009 Dec 20.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Cambridge, Old Addenbrooke's site, 80 Tennis Court Road, Cambridge CB2 1GA, UK. lynn@cryst.bioc.cam.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/20023628" target="_blank"〉PubMed〈/a〉
    Keywords: Antigens, Nuclear/chemistry ; Catalytic Domain ; Crystallography, X-Ray ; DNA/metabolism ; DNA Breaks, Double-Stranded ; DNA-Activated Protein Kinase/*chemistry/metabolism ; DNA-Binding Proteins/chemistry ; HeLa Cells ; *Helix-Turn-Helix Motifs ; Humans ; Models, Molecular ; Nuclear Proteins/*chemistry/metabolism ; Protein Folding ; Protein Structure, Secondary
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2008-11-18
    Description: Pentraxins are a family of ancient innate immune mediators conserved throughout evolution. The classical pentraxins include serum amyloid P component (SAP) and C-reactive protein, which are two of the acute-phase proteins synthesized in response to infection. Both recognize microbial pathogens and activate the classical complement pathway through C1q (refs 3 and 4). More recently, members of the pentraxin family were found to interact with cell-surface Fcgamma receptors (FcgammaR) and activate leukocyte-mediated phagocytosis. Here we describe the structural mechanism for pentraxin's binding to FcgammaR and its functional activation of FcgammaR-mediated phagocytosis and cytokine secretion. The complex structure between human SAP and FcgammaRIIa reveals a diagonally bound receptor on each SAP pentamer with both D1 and D2 domains of the receptor contacting the ridge helices from two SAP subunits. The 1:1 stoichiometry between SAP and FcgammaRIIa infers the requirement for multivalent pathogen binding for receptor aggregation. Mutational and binding studies show that pentraxins are diverse in their binding specificity for FcgammaR isoforms but conserved in their recognition structure. The shared binding site for SAP and IgG results in competition for FcgammaR binding and the inhibition of immune-complex-mediated phagocytosis by soluble pentraxins. These results establish antibody-like functions for pentraxins in the FcgammaR pathway, suggest an evolutionary overlap between the innate and adaptive immune systems, and have new therapeutic implications for autoimmune diseases.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2688732/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2688732/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Lu, Jinghua -- Marnell, Lorraine L -- Marjon, Kristopher D -- Mold, Carolyn -- Du Clos, Terry W -- Sun, Peter D -- R01 AI28358/AI/NIAID NIH HHS/ -- T32 AI007538/AI/NIAID NIH HHS/ -- Z01 AI000853-09/Intramural NIH HHS/ -- England -- Nature. 2008 Dec 18;456(7224):989-92. doi: 10.1038/nature07468. Epub 2008 Nov 16.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, Maryland 20852, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19011614" target="_blank"〉PubMed〈/a〉
    Keywords: Binding Sites ; Binding, Competitive ; C-Reactive Protein/chemistry/*immunology/*metabolism ; Crystallography, X-Ray ; Cytokines/immunology/secretion ; Humans ; Immunity, Innate/*immunology ; Immunoglobulin G/immunology/metabolism ; Macrophages/cytology/immunology ; Models, Molecular ; Phagocytosis ; Protein Conformation ; Receptors, IgG/chemistry/*immunology/*metabolism ; Serum Amyloid P-Component/chemistry/*immunology/*metabolism
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2008-02-01
    Description: The M2 protein from influenza A virus is a pH-activated proton channel that mediates acidification of the interior of viral particles entrapped in endosomes. M2 is the target of the anti-influenza drugs amantadine and rimantadine; recently, resistance to these drugs in humans, birds and pigs has reached more than 90% (ref. 1). Here we describe the crystal structure of the transmembrane-spanning region of the homotetrameric protein in the presence and absence of the channel-blocking drug amantadine. pH-dependent structural changes occur near a set of conserved His and Trp residues that are involved in proton gating. The drug-binding site is lined by residues that are mutated in amantadine-resistant viruses. Binding of amantadine physically occludes the pore, and might also perturb the pK(a) of the critical His residue. The structure provides a starting point for solving the problem of resistance to M2-channel blockers.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3889492/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3889492/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Stouffer, Amanda L -- Acharya, Rudresh -- Salom, David -- Levine, Anna S -- Di Costanzo, Luigi -- Soto, Cinque S -- Tereshko, Valentina -- Nanda, Vikas -- Stayrook, Steven -- DeGrado, William F -- R37 GM054616/GM/NIGMS NIH HHS/ -- T32 GM008275/GM/NIGMS NIH HHS/ -- England -- Nature. 2008 Jan 31;451(7178):596-9. doi: 10.1038/nature06528.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry and Biophysics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18235504" target="_blank"〉PubMed〈/a〉
    Keywords: Amantadine/chemistry/metabolism/pharmacology ; Crystallography, X-Ray ; Drug Resistance, Viral/genetics ; Histidine/metabolism ; Hydrogen-Ion Concentration ; Influenza A virus/*chemistry/genetics/metabolism ; Ion Channel Gating/drug effects ; Models, Molecular ; Protein Structure, Quaternary ; Protons ; Structure-Activity Relationship ; Tryptophan/metabolism ; Viral Matrix Proteins/*antagonists & inhibitors/*chemistry/genetics/metabolism
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2008-12-05
    Description: Species-specific recognition between the egg extracellular matrix (zona pellucida) and sperm is the first, crucial step of mammalian fertilization. Zona pellucida filament components ZP3 and ZP2 act as sperm receptors, and mice lacking either of the corresponding genes produce oocytes without a zona pellucida and are completely infertile. Like their counterparts in the vitelline envelope of non-mammalian eggs and many other secreted eukaryotic proteins, zona pellucida subunits polymerize using a 'zona pellucida (ZP) domain' module, whose conserved amino-terminal part (ZP-N) was suggested to constitute a domain of its own. No atomic structure has been reported for ZP domain proteins, and there is no structural information on any conserved vertebrate protein that is essential for fertilization and directly involved in egg-sperm binding. Here we describe the 2.3 angstrom (A) resolution structure of the ZP-N fragment of mouse primary sperm receptor ZP3. The ZP-N fold defines a new immunoglobulin superfamily subtype with a beta-sheet extension characterized by an E' strand and an invariant tyrosine residue implicated in polymerization. The structure strongly supports the presence of ZP-N repeats within the N-terminal region of ZP2 and other vertebrate zona pellucida/vitelline envelope proteins, with implications for overall egg coat architecture, the post-fertilization block to polyspermy and speciation. Moreover, it provides an important framework for understanding human diseases caused by mutations in ZP domain proteins and developing new methods of non-hormonal contraception.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Monne, Magnus -- Han, Ling -- Schwend, Thomas -- Burendahl, Sofia -- Jovine, Luca -- G0500367/Medical Research Council/United Kingdom -- England -- Nature. 2008 Dec 4;456(7222):653-7. doi: 10.1038/nature07599.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Karolinska Institutet, Department of Biosciences and Nutrition, Halsovagen 7, SE-141 57 Huddinge, Sweden.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19052627" target="_blank"〉PubMed〈/a〉
    Keywords: Amino Acid Sequence ; Animals ; Binding Sites ; CHO Cells ; Conserved Sequence ; Cricetinae ; Cricetulus ; Crystallization ; Crystallography, X-Ray ; Egg Proteins/*chemistry/genetics/*metabolism ; Female ; Male ; Membrane Glycoproteins/*chemistry/genetics/*metabolism ; Mice ; Models, Molecular ; Molecular Sequence Data ; Ovum/*chemistry/*metabolism ; Peptide Fragments/chemistry/genetics/metabolism ; Protein Folding ; Protein Structure, Secondary ; Protein Structure, Tertiary ; Receptors, Cell Surface/*chemistry/genetics/*metabolism ; Repetitive Sequences, Amino Acid ; Spermatozoa/metabolism
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2008-03-21
    Description: The design of new enzymes for reactions not catalysed by naturally occurring biocatalysts is a challenge for protein engineering and is a critical test of our understanding of enzyme catalysis. Here we describe the computational design of eight enzymes that use two different catalytic motifs to catalyse the Kemp elimination-a model reaction for proton transfer from carbon-with measured rate enhancements of up to 10(5) and multiple turnovers. Mutational analysis confirms that catalysis depends on the computationally designed active sites, and a high-resolution crystal structure suggests that the designs have close to atomic accuracy. Application of in vitro evolution to enhance the computational designs produced a 〉200-fold increase in k(cat)/K(m) (k(cat)/K(m) of 2,600 M(-1)s(-1) and k(cat)/k(uncat) of 〉10(6)). These results demonstrate the power of combining computational protein design with directed evolution for creating new enzymes, and we anticipate the creation of a wide range of useful new catalysts in the future.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rothlisberger, Daniela -- Khersonsky, Olga -- Wollacott, Andrew M -- Jiang, Lin -- DeChancie, Jason -- Betker, Jamie -- Gallaher, Jasmine L -- Althoff, Eric A -- Zanghellini, Alexandre -- Dym, Orly -- Albeck, Shira -- Houk, Kendall N -- Tawfik, Dan S -- Baker, David -- Howard Hughes Medical Institute/ -- England -- Nature. 2008 May 8;453(7192):190-5. doi: 10.1038/nature06879. Epub 2008 Mar 19.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Washington, Seattle, Washington 98195, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18354394" target="_blank"〉PubMed〈/a〉
    Keywords: Algorithms ; Amino Acid Motifs ; Binding Sites/genetics ; Catalysis ; Computational Biology ; *Computer Simulation ; Crystallography, X-Ray ; Directed Molecular Evolution/*methods ; Drug Design ; Drug Evaluation, Preclinical ; Enzymes/*chemistry/genetics/*metabolism ; Kinetics ; Models, Chemical ; Models, Molecular ; Protein Engineering/*methods ; Quantum Theory ; Sensitivity and Specificity
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2008-11-21
    Description: Calpains are non-lysosomal calcium-dependent cysteine proteinases that selectively cleave proteins in response to calcium signals and thereby control cellular functions such as cytoskeletal remodelling, cell cycle progression, gene expression and apoptotic cell death. In mammals, the two best-characterized members of the calpain family, calpain 1 and calpain 2 (micro-calpain and m-calpain, respectively), are ubiquitously expressed. The activity of calpains is tightly controlled by the endogenous inhibitor calpastatin, which is an intrinsically unstructured protein capable of reversibly binding and inhibiting four molecules of calpain, but only in the presence of calcium. To date, the mechanism of inhibition by calpastatin and the basis for its absolute specificity have remained speculative. It was not clear how this unstructured protein inhibits calpains without being cleaved itself, nor was it known how calcium induced changes that facilitated the binding of calpastatin to calpain. Here we report the 2.4-A-resolution crystal structure of the calcium-bound calpain 2 heterodimer bound by one of the four inhibitory domains of calpastatin. Calpastatin is seen to inhibit calpain by occupying both sides of the active site cleft. Although the inhibitor passes through the active site cleft it escapes cleavage in a novel manner by looping out and around the active site cysteine. The inhibitory domain of calpastatin recognizes multiple lower affinity sites present only in the calcium-bound form of the enzyme, resulting in an interaction that is tight, specific and calcium dependent. This crystal structure, and that of a related complex, also reveal the conformational changes that calpain undergoes on binding calcium, which include opening of the active site cleft and movement of the domains relative to each other to produce a more compact enzyme.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hanna, Rachel A -- Campbell, Robert L -- Davies, Peter L -- England -- Nature. 2008 Nov 20;456(7220):409-12. doi: 10.1038/nature07451.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, Queen's University, Kingston, Ontario, Canada K7L 3N6.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/19020623" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Calcium/*metabolism ; Calcium-Binding Proteins/*chemistry/*metabolism ; Calpain/*antagonists & inhibitors/*chemistry/metabolism ; Catalytic Domain ; Crystallography, X-Ray ; Models, Molecular ; Protein Binding ; Protein Multimerization ; Rats ; Structure-Activity Relationship
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2008-10-14
    Description: The APOBEC family members are involved in diverse biological functions. APOBEC3G restricts the replication of human immunodeficiency virus (HIV), hepatitis B virus and retroelements by cytidine deamination on single-stranded DNA or by RNA binding. Here we report the high-resolution crystal structure of the carboxy-terminal deaminase domain of APOBEC3G (APOBEC3G-CD2) purified from Escherichia coli. The APOBEC3G-CD2 structure has a five-stranded beta-sheet core that is common to all known deaminase structures and closely resembles the structure of another APOBEC protein, APOBEC2 (ref. 5). A comparison of APOBEC3G-CD2 with other deaminase structures shows a structural conservation of the active-site loops that are directly involved in substrate binding. In the X-ray structure, these APOBEC3G active-site loops form a continuous 'substrate groove' around the active centre. The orientation of this putative substrate groove differs markedly (by 90 degrees) from the groove predicted by the NMR structure. We have introduced mutations around the groove, and have identified residues involved in substrate specificity, single-stranded DNA binding and deaminase activity. These results provide a basis for understanding the underlying mechanisms of substrate specificity for the APOBEC family.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2714533/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2714533/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Holden, Lauren G -- Prochnow, Courtney -- Chang, Y Paul -- Bransteitter, Ronda -- Chelico, Linda -- Sen, Udayaditya -- Stevens, Raymond C -- Goodman, Myron F -- Chen, Xiaojiang S -- R01 AI055926/AI/NIAID NIH HHS/ -- R01 AI055926-05/AI/NIAID NIH HHS/ -- England -- Nature. 2008 Nov 6;456(7218):121-4. doi: 10.1038/nature07357. Epub 2008 Oct 12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Molecular and Computational Biology, University of Southern California, Los Angeles, California 90089, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18849968" target="_blank"〉PubMed〈/a〉
    Keywords: Antiviral Agents ; *Catalytic Domain ; Crystallography, X-Ray ; Cytidine Deaminase/*chemistry/genetics/isolation & purification/*metabolism ; DNA, Single-Stranded/metabolism ; Escherichia coli ; Humans ; Models, Molecular ; Muscle Proteins/chemistry ; Mutant Proteins/chemistry/genetics/metabolism ; Mutation ; Nuclear Magnetic Resonance, Biomolecular ; Protein Structure, Secondary ; Structural Homology, Protein ; Structure-Activity Relationship ; Substrate Specificity
    Print ISSN: 0028-0836
    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...