Open Access. Powered by Scholars. Published by Universities.®
Other Biochemistry, Biophysics, and Structural Biology Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Biochemistry (687)
- Biotechnology (493)
- Molecular Biology (155)
- Medicine and Health Sciences (134)
- Chemicals and Drugs (94)
-
- Amino Acids, Peptides, and Proteins (88)
- Physiology (88)
- Cellular and Molecular Physiology (85)
- Nucleic Acids, Nucleotides, and Nucleosides (76)
- Biology (55)
- Microbiology (55)
- Physical Sciences and Mathematics (54)
- Structural Biology (50)
- Biophysics (47)
- Cell and Developmental Biology (37)
- Medical Sciences (33)
- Chemistry (28)
- Medical Biochemistry (25)
- Cell Biology (21)
- Plant Sciences (21)
- Genetics and Genomics (20)
- Physics (19)
- Animal Sciences (18)
- Social and Behavioral Sciences (18)
- Engineering (16)
- Bioinformatics (15)
- Plant Biology (15)
- Institution
-
- University of Nebraska - Lincoln (470)
- Chapman University (89)
- Selected Works (42)
- University of Massachusetts Amherst (18)
- University of Tennessee, Knoxville (14)
-
- Marshall University (13)
- City University of New York (CUNY) (10)
- Technological University Dublin (9)
- WellBeing International (9)
- University of Denver (7)
- The University of Southern Mississippi (6)
- Western University (6)
- SelectedWorks (5)
- University of Louisville (5)
- Florida International University (4)
- University of Arkansas, Fayetteville (4)
- University of Connecticut (4)
- California Polytechnic State University, San Luis Obispo (3)
- Syracuse University (3)
- The Texas Medical Center Library (3)
- University of New Mexico (3)
- University of Tennessee Health Science Center (3)
- Virginia Commonwealth University (3)
- Western Kentucky University (3)
- Clemson University (2)
- College of Saint Benedict and Saint John's University (2)
- Duquesne University (2)
- Edith Cowan University (2)
- Illinois Math and Science Academy (2)
- Louisiana State University (2)
- Keyword
-
- Translation (15)
- TRNA (11)
- Cancer (10)
- Mitochondria (10)
- Biophysics (8)
-
- Apoptosis (7)
- Diet (7)
- Molecular dynamics (7)
- Oxidative stress (7)
- Photosynthesis (7)
- Arabidopsis thaliana (6)
- Heme (6)
- Lipids (6)
- Mass spectrometry (6)
- Metabolism (6)
- NMR (6)
- Omega-6 (6)
- Protein synthesis (6)
- Amino acid (5)
- Aminoacyl-tRNA synthetase (5)
- Archaea (5)
- B16 (5)
- Biochemistry (5)
- Chloroplast (5)
- DNA (5)
- Drug discovery (5)
- Malignant melanoma (5)
- Metabolomics (5)
- Obesity (5)
- Omega-3 (5)
- Publication Year
- Publication
-
- Department of Biochemistry: Faculty Publications (465)
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (83)
- Doctoral Dissertations (22)
- Electronic Theses and Dissertations (13)
- Articles (8)
-
- Biochemistry and Microbiology (8)
- Vincent E Sollars (8)
- Biochemistry Collection (7)
- Dissertations, Theses, and Capstone Projects (7)
- Honors Theses (6)
- Masters Theses (6)
- Electronic Thesis and Dissertation Repository (5)
- Faculty Publications (5)
- Goldi A Kozloski (5)
- Master's Theses (5)
- Theses, Dissertations and Capstones (5)
- Dissertations (4)
- Elaine Hardman Ph.D. (4)
- Theses and Dissertations (4)
- DU Undergraduate Research Journal Archive (3)
- Dissertations & Theses (Open Access) (3)
- FIU Electronic Theses and Dissertations (3)
- Fabienne Paumet (3)
- Gabriela Ion (3)
- Honors Capstone Projects - All (3)
- Mathematics, Physics, and Computer Science Faculty Articles and Research (3)
- fouad Lemtiri-Chlieh (3)
- Aquaculture Collection (2)
- Biochemistry -- Faculty Publications (2)
- CSB/SJU Distinguished Thesis (2)
- Publication Type
- File Type
Articles 721 - 750 of 802
Full-Text Articles in Other Biochemistry, Biophysics, and Structural Biology
Purification And Initial Biochemical Characterization Of Atp:Cob(I)Alamin Adenosyltransferase (Eutt) Enzyme Of Salmonella Enterica, Nicole R. Baun, Jorge C. Escalante-Semerena
Purification And Initial Biochemical Characterization Of Atp:Cob(I)Alamin Adenosyltransferase (Eutt) Enzyme Of Salmonella Enterica, Nicole R. Baun, Jorge C. Escalante-Semerena
Department of Biochemistry: Faculty Publications
ATP:cob(I)alamin adenosyltransferase (EutT) of Salmonella
enterica was overproduced and enriched to ~70% homogeneity,
and its basic kinetic parameters were determined. Abundant
amounts of EutT protein were produced, but all of it remained
insoluble. Soluble active EutT protein (~70% homogeneous) was
obtained after treatment with detergent. Under conditions in which
cobalamin (Cbl) was saturating, Km(ATP) = 10 µM, kcat = 0.03 s-1,
and Vmax = 54.5 nM min-1. Similarly, under conditions in which
MgATPwas saturating,Km(Cbl) = 4.1µM, kcat = 0.06 s-1, andVmax= …
Sequential Processing Of A Mitochondrial Tandem Protein: Insights Into Protein Import In Schizosaccharomyces Pombe, Oleh Khalimonchuk, Martin Ott, Soledad Funes, Kai Ostermann, Gerhard Rödel, Johannes M. Herrmann
Sequential Processing Of A Mitochondrial Tandem Protein: Insights Into Protein Import In Schizosaccharomyces Pombe, Oleh Khalimonchuk, Martin Ott, Soledad Funes, Kai Ostermann, Gerhard Rödel, Johannes M. Herrmann
Department of Biochemistry: Faculty Publications
The sequencing of the genome of Schizosaccharomyces pombe revealed the presence of a number of genes encoding tandem proteins, some of which are mitochondrial components. One of these proteins (pre-Rsm22- Cox11) consists of a fusion of Rsm22, a component of the mitochondrial ribosome, and Cox11, a factor required for copper insertion into cytochrome oxidase. Since in Saccharomyces cerevisiae, Cox11 is physically attached to the mitochondrial ribosome, it was suggested that the tandem organization of Rsm22-Cox11 is used to covalently tie the mitochondrial ribosome to Cox11 in S. pombe. We report here that pre-Rsm22-Cox11 is matured in two subsequent …
Differential Effects Of Sodium And Magnesium Sulfate On Water Consumption By Beef Cattle, A. S. Grout, D. M. Veira, D. M. Weary, M. A. G. Von Keyserlingk, D. Fraser
Differential Effects Of Sodium And Magnesium Sulfate On Water Consumption By Beef Cattle, A. S. Grout, D. M. Veira, D. M. Weary, M. A. G. Von Keyserlingk, D. Fraser
Biochemistry Collection
The existing guidelines for maximum sulfate (SO4) in cattle drinking water are based on Na2SO4, although many water sources contain greater concentrations of MgSO4. Two experiments compared the effect of different SO4 salts on water consumption and fecal DM of cattle. In Exp. 1, 8 yearling heifers (initial BW = 345 ± 8 kg; mean ± SD) were watered twice daily with tapwater or water containing Na2SO4 or MgSO4 at target levels of 1,500, 3,000, or 4,500 mg of SO4/L for 2-d treatment periods separated by 2 …
Computer-Assisted Docking Of Flavodoxin With The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Reveals Residues Critical For Protein-Protein Interactions But Not For Catalysis*, Nicole R. Buan, Jorge C. Escalante-Semerena
Computer-Assisted Docking Of Flavodoxin With The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Reveals Residues Critical For Protein-Protein Interactions But Not For Catalysis*, Nicole R. Buan, Jorge C. Escalante-Semerena
Department of Biochemistry: Faculty Publications
The activity of the housekeeping ATP:co(I)rrinoid adenosyltransferase (CobA) enzyme of Salmonella enterica sv. Typhimurium is required to adenosylate de novo biosynthetic intermediates of adenosylcobalamin and to salvage incomplete and complete corrinoids from the environment of this bacterium. In vitro, reduced flavodoxin (FldA) provides an electron to generate the co(I)rrinoid substrate in the CobA active site. To understand how CobAand FldA interact, a computer model of aCobA∙FldA complex was generated. This model was used to guide the introduction of mutations into CobA using site-directed mutagenesis and the synthesis of a peptide mimic of FldA. Residues Arg-9 and Arg-165 of CobA …
Loss Of Editing Activity During The Evolution Of Mitochondrial Phenylalanyl-Trna Synthetase, Hervé Roy, Jiqiang Ling, Juan D. Alfonzo, Michael Ibba
Loss Of Editing Activity During The Evolution Of Mitochondrial Phenylalanyl-Trna Synthetase, Hervé Roy, Jiqiang Ling, Juan D. Alfonzo, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Accurate selection of amino acids is essential for faithful translation of the genetic code. Errors during amino acid selection are usually corrected by the editing activity of aminoacyl-tRNA synthetases such as phenylalanyl-tRNA synthetases (PheRS), which edit misactivated tyrosine. Comparison of cytosolic and mitochondrial PheRS from the yeast Saccharomyces cerevisiae suggested that the organellar protein might lack the editing activity. Yeast cytosolic PheRS was found to contain an editing site, which upon disruption abolished both cis and trans editing of Tyr-tRNAPhe. Wild-type mitochondrial PheRS lacked cis and trans editing and could synthesize Tyr-tRNAPhe, an activity enhanced in …
Association Between Archaeal Prolyl- And Leucyl-Trna Synthetases Enhances TrnaPro Aminoacylation, Mette Praetorius-Ibba, Theresa E. Rogers, Rachel Samson, Zvi Kelman, Michael Ibba
Association Between Archaeal Prolyl- And Leucyl-Trna Synthetases Enhances TrnaPro Aminoacylation, Mette Praetorius-Ibba, Theresa E. Rogers, Rachel Samson, Zvi Kelman, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Aminoacyl-tRNA synthetase-containing complexes have been identified in different eukaryotes, and their existence has also been suggested in some Archaea. To investigate interactions involving aminoacyl-tRNA synthetases in Archaea, we undertook a yeast two-hybrid screen for interactions between Methanothermobacter thermautotrophicus proteins using prolyl-tRNA synthetase (ProRS) as the bait. Interacting proteins identified included components of methanogenesis, protein-modifying factors, and leucyl-tRNA synthetase (LeuRS). The association of ProRS with LeuRS was confirmed in vitro by native gel electrophoresis and size exclusion chromatography. Determination of the steady-state kinetics of tRNAPro charging showed that the catalytic efficiency (kcat/Km) of ProRS increased 5-fold …
The Epigenomic Viewpoint On Cellular Differentiation Of Myeloid Progenitor Cells As It Pertains To Leukemogenesis, Vincent E. Sollars
The Epigenomic Viewpoint On Cellular Differentiation Of Myeloid Progenitor Cells As It Pertains To Leukemogenesis, Vincent E. Sollars
Biochemistry and Microbiology
The new millennium has brought with it a surge of research in the field of epigenetics. This has included advances in our understanding of stem cell characteristics and mechanisms of commitment to cell lineages prior to differentiation. The nature of stem cells is similar to that of malignant cells in that they have unlimited self-renewal and protection from apoptosis, leading researchers to suspect that stem cells are the target of oncogenesis. This review will explore the idea of how epigenetic control of gene expression may contribute to mechanisms controlling differentiation of myeloid progenitor cells and its importance to our understanding …
Computer-Assisted Docking Of Flavodoxin With The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Reveals Residues Critical For Protein-Protein Interactions But Not For Catalysis, Nicole R. Baun, Jorge C. Escalante-Semerena
Computer-Assisted Docking Of Flavodoxin With The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Reveals Residues Critical For Protein-Protein Interactions But Not For Catalysis, Nicole R. Baun, Jorge C. Escalante-Semerena
Department of Biochemistry: Faculty Publications
The activity of the housekeeping ATP:co(I)rrinoid adenosyltransferase
(CobA) enzyme of Salmonella enterica sv. Typhimurium
is required to adenosylate de novo biosynthetic intermediates
of adenosylcobalamin and to salvage incomplete and complete
corrinoids from the environment of this bacterium. In vitro,
reduced flavodoxin (FldA) provides an electron to generate the
co(I)rrinoid substrate in the CobA active site. To understand how
CobAand FldA interact, a computer model of aCobA-FldA complex
was generated. This model was used to guide the introduction of
mutations into CobA using site-directed mutagenesis and the synthesis
of a peptide mimic of FldA. Residues Arg-9 and Arg-165 of
CobA …
Quality Control During Aminoacyl-Trna Synthesis, M. Praetorius-Ibba, S. Ataide, C. Hausmann, J. Levengood, J. Ling, S. Wang, H. Roy, Michael Ibba
Quality Control During Aminoacyl-Trna Synthesis, M. Praetorius-Ibba, S. Ataide, C. Hausmann, J. Levengood, J. Ling, S. Wang, H. Roy, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
The fidelity of translation is determined at two major points: the accuracy of aminoacyl-tRNA selection by the ribosomes and synthesis of cognate amino acid/tRNA pairs by aminoacyl-tRNA synthetases (aaRSs) in the course of the aminoacylation reaction. The most important point in aminoacylation is the accurate recognition of cognate substrates coupled with discrimination of non-cognates. While this is generally accomplished by a single enzyme, we have recently found that discrimination against lysine analogues requires the existence of two unrelated lysyl-tRNA synthetases. For other amino acids, initial recognition is not sufficiently accurate with errors being corrected by an intrinsic editing activity. Recent …
Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber
Growth And Transport Properties Of Complementary Germanium Nanowire Field Effect Transistors, Andrew B. Greytak, Lincoln J. Lauhon, Mark S. Gudiksen, Charles M. Lieber
Faculty Publications
n- and p-type Ge nanowires were synthesized by a multistep process in which axial elongation, via vapor–liquid–solid (VLS) growth, and doping were accomplished in separate chemical vapor deposition steps. Intrinsic, single-crystal, Ge nanowires prepared by Au nanocluster-mediated VLS growth were surface-doped in situ using diborane or phosphine, and then radial growth of an epitaxial Ge shell was used to cap the dopant layer. Field-effect transistors prepared from these Ge nanowires exhibited on currents and transconductances up to 850 µA/µm and 4.9 µA/V, respectively, with device yields of >85%.
Photoreactive Bicyclic Amino Acids As Substrates For Mutant Escherichia Coli Phenylalanyl-Trna Synthetases, Thomas Bentin, Ramin Hamzavi, Jahan Salomonsson, Hervé Roy, Michael Ibba, Peter E. Nielsen
Photoreactive Bicyclic Amino Acids As Substrates For Mutant Escherichia Coli Phenylalanyl-Trna Synthetases, Thomas Bentin, Ramin Hamzavi, Jahan Salomonsson, Hervé Roy, Michael Ibba, Peter E. Nielsen
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Unnatural amino acids carrying reactive groups that can be selectively activated under non-invasive biologically benign conditions are of interest in protein engineering as biological tools for the analysis of protein-protein and protein-nucleic acids interactions. The double ring system phenylalanine analogues benzofuranylalanine and benzotriazolylalanine were synthesized, and their photolability was tested by UV irradiation at 254, 320, and 365 nm. Although both showed photo reactivity, benzofuranylalanine appeared as the most promising compound because this amino acid was activated by UVA (long wavelength) irradiation. These amino acids were also tested for in vitro charging of tRNAPhe and for protein mutagenesis via …
Differences In Response To Hypoxia In The Three-Spined Stickleback From Lotic And Lentic Localities: Dominance And An Anaerobic Metabolite, L. U. Sneddon, J. Yerbury
Differences In Response To Hypoxia In The Three-Spined Stickleback From Lotic And Lentic Localities: Dominance And An Anaerobic Metabolite, L. U. Sneddon, J. Yerbury
Aquaculture Collection
Dominance hierarchies of the three-spined stickleback Gasterosteus aculeatus from river and pond populations were subjected to hypoxia (20%, range±1%). Under hypoxia, the hierarchies were less stable in terms of rank position and tissue L-lactate was higher in river fish than pond fish under normoxia and hypoxia. Dominant fish gained mass under normoxia but lost mass under hypoxic conditions possibly due to them maintaining high levels of aggression.
The Identity Of Proteins Associated With A Small Heat Shock Protein During Heat Stress In Vivo Indicates That These Chaperones Protect A Wide Range Of Cellular Functions, Eman Basha, Garrett J. Lee, Linda A. Breci, Andrew C. Hausrath, Nicole R. Buan, Kim C. Giese, Elizabeth Vierling
The Identity Of Proteins Associated With A Small Heat Shock Protein During Heat Stress In Vivo Indicates That These Chaperones Protect A Wide Range Of Cellular Functions, Eman Basha, Garrett J. Lee, Linda A. Breci, Andrew C. Hausrath, Nicole R. Buan, Kim C. Giese, Elizabeth Vierling
Department of Biochemistry: Faculty Publications
The small heat shock proteins (sHSPs) are a ubiquitous class of ATP-independent chaperones believed to prevent irreversible protein aggregation and to facilitate subsequent protein renaturation in cooperation with ATP-dependent chaperones. Although sHSP chaperone activity has been studied extensively in vitro, understanding the mechanism of sHSP function requires identification of proteins that are sHSP substrates in vivo. We have used both immunoprecipitation and affinity chromatography to recover 42 proteins that specifically interact with Synechocystis Hsp16.6 in vivo during heat treatment. These proteins can all be released from Hsp16.6 by the ATP-dependent activity of DnaK and cochaperones and are heat-labile. Thirteen …
Divergence In Non-Cognate Amino Acid Recognition Between Class I And Class Ii Lysyl-Trna Synthetases, Jeffrey D. Levengood, Sandro F. Ataide, Hervé Roy, Michael Ibba
Divergence In Non-Cognate Amino Acid Recognition Between Class I And Class Ii Lysyl-Trna Synthetases, Jeffrey D. Levengood, Sandro F. Ataide, Hervé Roy, Michael Ibba
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Lysine insertion during coded protein synthesis requires lysyl-tRNALys, which is synthesized by lysyl-tRNA synthetase (LysRS). Two unrelated forms of LysRS are known: LysRS2, which is found in eukaryotes, most bacteria, and a few archaea, and LysRS1, which is found in most archaea and a few bacteria. To compare amino acid recognition between the two forms of LysRS, the effects of l-lysine analogues on aminoacylation were investigated. Both enzymes showed stereospecificity toward the l-enantiomer of lysine and discriminated against noncognate amino acids with different R-groups (arginine, ornithine). Lysine analogues containing substitutions at other positions were generally most effective as …
5-Hydroxydecanoate Is Metabolised In Mitochondria And Creates A Rate-Limiting Bottleneck For Β-Oxidation Of Fatty Acids, Peter J. Hanley, Stefan Dröse, Ulrich Brandt, Rachel A. Lareau, Abir L. Banerjee, D. K. Srivastava, Leonard J. Banaszak, Joseph J. Barycki, Paul P. Van Veldhoven, Jürgen Daut
5-Hydroxydecanoate Is Metabolised In Mitochondria And Creates A Rate-Limiting Bottleneck For Β-Oxidation Of Fatty Acids, Peter J. Hanley, Stefan Dröse, Ulrich Brandt, Rachel A. Lareau, Abir L. Banerjee, D. K. Srivastava, Leonard J. Banaszak, Joseph J. Barycki, Paul P. Van Veldhoven, Jürgen Daut
Department of Biochemistry: Faculty Publications
5-Hydroxydecanoate (5-HD) blocks pharmacological and ischaemic preconditioning, and
has been postulated to be a specific inhibitor of mitochondrial ATP-sensitive K+ (KATP)
channels. However, recent work has shown that 5-HD is activated to 5-hydroxydecanoyl-CoA
(5-HD-CoA), which is a substrate for the first step of β-oxidation. We have now
analysed the complete β-oxidation of 5-HD-CoA using specially synthesised (and purified)
substrates and enzymes, as well as isolated rat liver and heart mitochondria, and compared
it with the metabolism of the physiological substrate decanoyl-CoA. At the second step of
β-oxidation, catalysed by enoyl-CoA hydratase, enzyme kinetics were …
Interactions Between Small Heat Shock Protein Subunits And Substrate In Small Heat Shock Protein-Substrate Complexes, Kenneth L. Friedrich, Kim C. Giese, Nicole R. Baun, Elizabeth Vierling
Interactions Between Small Heat Shock Protein Subunits And Substrate In Small Heat Shock Protein-Substrate Complexes, Kenneth L. Friedrich, Kim C. Giese, Nicole R. Baun, Elizabeth Vierling
Department of Biochemistry: Faculty Publications
Small heat shock proteins (sHSPs) are dynamic oligomeric
proteins that bind unfolding proteins and protect
them from irreversible aggregation. This binding results
in the formation of sHSP-substrate complexes from
which substrate can later be refolded. Interactions between
sHSP and substrate in sHSP-substrate complexes
and the mechanism by which substrate is transferred to
ATP-dependent chaperones for refolding are poorly defined.
We have established C-terminal affinity-tagged
sHSPs from a eukaryote (pea HSP18.1) and a prokaryote
(Synechocystis HSP16.6) as tools to investigate these issues.
We demonstrate that sHSP subunit exchange for
HSP18.1 and HSP16.6 is temperature-dependent and
rapid at the optimal growth …
Interactions Between Small Heat Shock Protein Subunits And Substrate In Small Heat Shock Protein-Substrate Complexes, Kenneth L. Friedrich,, Kim C. Giese, Nicole R. Buan, Elizabeth Vierling
Interactions Between Small Heat Shock Protein Subunits And Substrate In Small Heat Shock Protein-Substrate Complexes, Kenneth L. Friedrich,, Kim C. Giese, Nicole R. Buan, Elizabeth Vierling
Department of Biochemistry: Faculty Publications
Small heat shock proteins (sHSPs) are dynamic oligomeric proteins that bind unfolding proteins and protect them from irreversible aggregation. This binding results in the formation of sHSP-substrate complexes from which substrate can later be refolded. Interactions between sHSP and substrate in sHSP-substrate complexes and the mechanism by which substrate is transferred to ATP-dependent chaperones for refolding are poorly defined. We have established C-terminal affinity-tagged sHSPs from a eukaryote (pea HSP18.1) and a prokaryote (Synechocystis HSP16.6) as tools to investigate these issues. We demonstrate that sHSP subunit exchange for HSP18.1 and HSP16.6 is temperature-dependent and rapid at the optimal growth temperature …
Altered Phosphorylation Of [Beta]-Catenin In Glucocorticoid Treated 235-1 Rat Pituitary Tumor Cells, Susie K. Saunders
Altered Phosphorylation Of [Beta]-Catenin In Glucocorticoid Treated 235-1 Rat Pituitary Tumor Cells, Susie K. Saunders
Theses, Dissertations and Capstones
Beta-catenin is an essential cell adhesion and signaling protein, associated with high prolactin levels in rat pituitary tumor cells. It has been shown that phosphorylation affects the location and activity of b-catenin. Glycogen synthase kinase (GSK3-b) is a serine-threonine kinase that phosphorylates b-catenin on N-terminal residues, targeting it for proteasomal degradation. Studies have shown that C-terminal tyrosine phosphorylation decreases the association of b-catenin with cadherin. In 235-1 rat pituitary tumor cells, our lab has shown that the glucocorticoid analog dexamethasone (Dex) decreases the half- life of b-catenin while increasing the activity of GSK3-b. The current study was undertaken to examine …
Mobilization Of Intracellular Copper Stores By The Ctr2 Vacuolar Copper Transporter, Erin M. Rees, Jaekwon Lee, Dennis J. Thiele
Mobilization Of Intracellular Copper Stores By The Ctr2 Vacuolar Copper Transporter, Erin M. Rees, Jaekwon Lee, Dennis J. Thiele
Department of Biochemistry: Faculty Publications
Copper plays an essential role in processes including signaling to the transcription and protein trafficking machinery, oxidative phosphorylation, iron mobilization, neuropeptide maturation, and normal development. Whereas much is known about intracellular mobilization of ions such as calcium, little information is available on how eukaryotic cells mobilize intracellular copper stores. We describe a mechanism by which the Saccharomyces cerevisiae Ctr2 protein provides bioavailable copper via mobilization of intracellular copper stores. Whereas Ctr2 exhibits structural similarity to the Ctr1 plasma membrane copper importer, microscopic and biochemical fractionation studies localize Ctr2 to the vacuole membrane. We demonstrate that Ctr2 mobilizes vacuolar copper stores …
The Identity Of Proteins Associated With A Small Heat Shock Protein During Heat Stress In Vivo Indicates That These Chaperones Protect A Wide Range Of Cellular Functions, Eman Basha, Garrett J. Lee, Linda A. Breci, Andrew C. Hausrath, Nicole R. Baun, Kim C. Giese, Elizabeth Vierling
The Identity Of Proteins Associated With A Small Heat Shock Protein During Heat Stress In Vivo Indicates That These Chaperones Protect A Wide Range Of Cellular Functions, Eman Basha, Garrett J. Lee, Linda A. Breci, Andrew C. Hausrath, Nicole R. Baun, Kim C. Giese, Elizabeth Vierling
Department of Biochemistry: Faculty Publications
The small heat shock proteins (sHSPs) are a ubiquitous
class of ATP-independent chaperones believed to
prevent irreversible protein aggregation and to facilitate
subsequent protein renaturation in cooperation
with ATP-dependent chaperones. Although sHSP chaperone
activity has been studied extensively in vitro, understanding
the mechanism of sHSP function requires
identification of proteins that are sHSP substrates in
vivo. We have used both immunoprecipitation and affinity
chromatography to recover 42 proteins that specifically
interact with Synechocystis Hsp16.6 in vivo during
heat treatment. These proteins can all be released from
Hsp16.6 by the ATP-dependent activity of DnaK and cochaperones
and are heat-labile. …
Aminoacyl-Trnas: Setting The Limits Of The Genetic Code, Michael Ibba, Dieter Söll
Aminoacyl-Trnas: Setting The Limits Of The Genetic Code, Michael Ibba, Dieter Söll
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Aminoacyl-tRNAs (aa-tRNAs) are simple molecules with a single purpose—to serve as substrates for translation. They consist of mature tRNAs to which an amino acid has been esterified at the 3′-end. The 20 different types of aa-tRNA are made by the 20 different aminoacyl-tRNA synthetases (aaRSs, of which there are two classes), one for each amino acid of the genetic code (Ibba and Söll 2000). This would be fine if it were not for the fact that such a straightforward textbook scenario is not true in a single known living organism. aa-tRNAs lie at the heart of gene expression; they interpret …
Transmembrane Movement Of Exogenous Long-Chain Fatty Acids: Proteins, Enzymes, And Vectorial Esterification, Paul N. Black, Concetta C. Dirusso
Transmembrane Movement Of Exogenous Long-Chain Fatty Acids: Proteins, Enzymes, And Vectorial Esterification, Paul N. Black, Concetta C. Dirusso
Department of Biochemistry: Faculty Publications
INTRODUCTION......................................................................................................................................................454
FATTY ACIDS AND BIOLOGICAL MEMBRANES.............................................................................................455
Fatty Acid Transport Defined ...............................................................................................................................456
MODEL SYSTEMS TO INVESTIGATE FATTY ACID TRANSPORT ..............................................................456
Genetic Foundations of Fatty Acid Transport....................................................................................................456
PROTEINS IMPLICATED IN FATTY ACID TRANSPORT ...............................................................................456
Fatty Acid Translocase..........................................................................................................................................457
Fatty Acid Binding Protein—Membrane Bound ................................................................................................457
Fatty Acid Transport Protein...............................................................................................................................458
The Long-Chain Fatty Acid Transport Protein FadL .......................................................................................458
Fatty Acyl-CoA Synthetase ...................................................................................................................................459
VECTORIAL ACYLATION: ONE MECHANISM OPERATIONAL IN FATTY ACID TRANSPORT...........460
THE BACTERIAL PARADIGM ...............................................................................................................................460
Energetics of Fatty Acid Transport in Gram-Negative Bacteria......................................................................460
The Fatty Acid Transporter FadL........................................................................................................................461
The Fatty Acyl-CoA Synthetase FadD..................................................................................................................461
Structural Considerations of FACS .....................................................................................................................462
FATTY ACID TRANSPORT AND ACTIVATION IN YEAST: …
The Many Faces Of Vitamin B12: Catalysis By Cobalamin-Dependent Enzymes, Ruma Banerjee, Stephen W. Ragsdale
The Many Faces Of Vitamin B12: Catalysis By Cobalamin-Dependent Enzymes, Ruma Banerjee, Stephen W. Ragsdale
Department of Biochemistry: Faculty Publications
Vitamin B12 is a complex organometallic cofactor associated with three subfamilies of enzymes: the adenosylcobalamin-dependent isomerases, the methylcobalamin-dependent methyltransferases, and the dehalogenases. Different chemical aspects of the cofactor are exploited during catalysis by the isomerases and the methyltransferases. Thus, the cobalt-carbon bond ruptures homolytically in the isomerases, whereas it is cleaved heterolytically in the methyltransferases. The reaction mechanism of the dehalogenases, the most recently discovered class of B12 enzymes, is poorly understood. Over the past decade our understanding of the reaction mechanisms of B12 enzymes has been greatly enhanced by the availability of large amounts of enzyme …
Evidence For An Epigenetic Mechanism By Which Hsp90 Acts As A Capacitor For Morphological Evolution, Vincent E. Sollars, Xiangyi Lu, Li Xiao, Xiaoyan Wang, Mark D. Garfinkel, Douglas M. Ruden
Evidence For An Epigenetic Mechanism By Which Hsp90 Acts As A Capacitor For Morphological Evolution, Vincent E. Sollars, Xiangyi Lu, Li Xiao, Xiaoyan Wang, Mark D. Garfinkel, Douglas M. Ruden
Biochemistry and Microbiology
Morphological alterations have been shown to occur in Drosophila melanogaster when function of Hsp90 (heat shock 0-kDa protein 1α, encoded by Hsp83) is compromised during development1. Genetic selection maintains the altered phenotypes in subsequent generations1. Recent experiments have shown, however, that phenotypic variation still occurs in nearly isogenic recombinant inbred strains of Arabidopsis thaliana2. Using a sensitized isogenic D. melanogaster strain, iso-KrIf-1, we confirm this finding and present evidence supporting an epigenetic mechanism for Hsp90’s capacitor function, whereby reduced activity of Hsp90 induces a heritably altered chromatin state. The altered chromatin state is evidenced by ectopic expression …
The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Of Salmonella Enterica Requires The 2'-Oh Group Of Atp For Function And Yields Inorganic Triphosphate As Its Reaction Byproduct, Maris V. Fonseca, Nicole R. Buan, Alexander R. Horswill, Ivan Rayment, Jorge C. Escalante-Semerena
The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Of Salmonella Enterica Requires The 2'-Oh Group Of Atp For Function And Yields Inorganic Triphosphate As Its Reaction Byproduct, Maris V. Fonseca, Nicole R. Buan, Alexander R. Horswill, Ivan Rayment, Jorge C. Escalante-Semerena
Department of Biochemistry: Faculty Publications
The specificity of the ATP:corrinoid adenosyltransferase (CobA) enzyme of Salmonella enterica serovar Typhimurium LT2 for its nucleotide substrate was tested using ATP analogs and alternative nucleotide donors. The enzyme showed broad specificity for the nucleotide base and required the 2’-OH group of the ribosyl moiety of ATP for activity. 31P NMR spectroscopy was used to identify inorganic triphosphate (PPPi) as the byproduct of the reaction catalyzed by the CobA enzyme. Cleavage of triphosphate into pyrophosphate and orthophosphate did not occur, indicating that triphosphate cleavage was not required for release of the adenosylcorrinoid product. Triphosphate was a strong …
Vectorial Acylation In Saccharomyces Cerevisiae, Zhiying Zou, Fumin Tong, Nils J. Færgeman, Claus Børsting, Paul N. Black, Concetta Dirusso
Vectorial Acylation In Saccharomyces Cerevisiae, Zhiying Zou, Fumin Tong, Nils J. Færgeman, Claus Børsting, Paul N. Black, Concetta Dirusso
Department of Biochemistry: Faculty Publications
In Saccharomyces cerevisiae Fat1p and fatty acyl-CoA synthetase (FACS) are hypothesized to couple import and activation of exogenous fatty acids by a process called vectorial acylation. Molecular genetic and biochemical studies were used to define further the functional and physical interactions between these proteins. Multicopy extragenic suppressors were selected in strains carrying deletions in FAA1 and FAA4 or FAA1 and FAT1. Each strain is unable to grow under synthetic lethal conditions when exogenous long-chain fatty acids are required, and neither strain accumulates the fluorescent long-chain fatty acid C1-BODIPY-C12 indicating a fatty acid transport defect. By using these …
Serotyping Group B Streptococci In A Small Community Hospital: An Analysis Of Distribution And Site Of Isolation, Jennifer M. Smith, Jason A. Rexroth, David G. Chaffin, Susan H. Jackman
Serotyping Group B Streptococci In A Small Community Hospital: An Analysis Of Distribution And Site Of Isolation, Jennifer M. Smith, Jason A. Rexroth, David G. Chaffin, Susan H. Jackman
Biochemistry and Microbiology
Objective: To determine the prevalence and site of isolation of different serotypes of group B streptococcus (GBS) colonization or infection at a small community hospital.
Methods: GBS isolates were obtained from a small community hospital and were then serotyped as la, Ib, II, III, IV, V or non-typeable. Hospital records were reviewed for patient sex, age and pregnancy status as well as the site of GBS isolation.
Results: GBS serotypes Ia, III and V were most common and accounted for over 60% of the total number of isolates. Serotype Ia was most prevalent in reproductive-age females, while serotypes V and …
Murine Epidermal Cell Antigen (Skn)-Directed Autoimmunity Induced By Transfer Of Cd4+ T Cells, Susan H. Jackman, Shivaleela Keerthy, Giselle Perry
Murine Epidermal Cell Antigen (Skn)-Directed Autoimmunity Induced By Transfer Of Cd4+ T Cells, Susan H. Jackman, Shivaleela Keerthy, Giselle Perry
Biochemistry and Microbiology
While pathogenic T cells have been identified for several diseases with epithelial cell damage, an autoimmune T cell-mediated response targeted against a known keratinocyte antigen has not been reported. Previously we described an autoimmune response directed to the mouse epidermal cell antigens, Skn. For our murine model, primed Skn-immune lymphocytes are adoptively transferred to recipients, which develop lesions at the site of mild skin trauma. In this study we investigated the nature of the autoimmune component of the Skn response. A time-course study demonstrated a relationship between the number of primed Sknimmune cells injected and the severity of skin lesions …
The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Of Salmonella Enterica Requires The 2’-Oh Group Of Atp For Function And Yields Inorganic Triphosphate As Its Reaction Byproduct, Maris V. Fonseca, Nicole R. Baun, Alexander R. Horswill, Ivan Rayment, Jorge C. Escalante-Semerena
The Atp:Co(I)Rrinoid Adenosyltransferase (Coba) Enzyme Of Salmonella Enterica Requires The 2’-Oh Group Of Atp For Function And Yields Inorganic Triphosphate As Its Reaction Byproduct, Maris V. Fonseca, Nicole R. Baun, Alexander R. Horswill, Ivan Rayment, Jorge C. Escalante-Semerena
Department of Biochemistry: Faculty Publications
The specificity of the ATP:corrinoid adenosyltransferase
(CobA) enzyme of Salmonella enterica serovar
Typhimurium LT2 for its nucleotide substrate was
tested using ATP analogs and alternative nucleotide donors.
The enzyme showed broad specificity for the nucleotide
base and required the 2’-OH group of the ribosyl
moiety of ATP for activity. 31P NMR spectroscopy
was used to identify inorganic triphosphate (PPPi) as
the byproduct of the reaction catalyzed by the CobA
enzyme. Cleavage of triphosphate into pyrophosphate
and orthophosphate did not occur, indicating that
triphosphate cleavage was not required for release of
the adenosylcorrinoid product. Triphosphate was …
Shape Imprinting Due To Variable Disulfide Bonds In Polyacrylamide Gels, Andrew B. Greytak, Alexander Y. Grosberg, Toyoichi Tanaka
Shape Imprinting Due To Variable Disulfide Bonds In Polyacrylamide Gels, Andrew B. Greytak, Alexander Y. Grosberg, Toyoichi Tanaka
Faculty Publications
Through the use of variable disulfide crosslinkers, we have created polyacrylamide gels whose shape can be altered after polymerization. N,N'-bisacryloylcystamine is incorporated as a crosslinker, along with a smaller amount of a permanent crosslinker. After polymerization, the disulfide bonds are cleaved into thiols through reduction. By reoxidizing the thiols with the gel held in a new macroscopic shape, a new set of disulfide bonds is formed, and the gel is forced to adopt the new shape. Retension of the new shape improves with greater distortion from the original shape, as well as with increased concentration of variable …