Life Sciences Commons^™

Circular Dichroism And Molecular Modeling Yield A Structure For The Complex Of Human Immunodeficiency Virus Type 1 Trans-Activation Response Rna And The Binding Region Of Tat, The Trans-Acting Transcriptional Activator, Erwann P. Loret, Philippe T. Georgel, W. Curtis Johnson Jr., Pui Shing Ho

Biological Sciences Faculty Research

Transcription in the human immunodeficiency virus type 1 (HIV-1) retrovirus is regulated by binding the viral Tat protein (trans-acting transcriptional activator) to the trans-activation response (TAR) RNA sequence. Here, vacuum UV circular dichroism (VUV-CD) is used to study the structure of TAR and its complex with two peptide fragments that are important for Tat binding to TAR. The VUV-CD spectrum of TAR is typical of A-form RNA and is minimally perturbed when bound to either the short or the long Tat peptide. The CD spectra ofthe complexes indicate an extended structure in the argnine-rich region of Tat from amino acid …

The Structure Of A Complex Of Bovine Ɑ-Thrombin And Recombinant Hirudin At 2.8-Å Resolution, Jacqueline Vitali, Philip D. Martin, Michael G. Malkowski, William D. Robertson, Jerome B. Lazar, Richard C. Winant, Paul H. Johnson, Brian Fp Edwards

Biochemistry and Molecular Biology Faculty Publications

Crystals of the complex of bovine alpha-thrombin with recombinant hirudin variant 1 have space group C222(1) with cell constants a = 59.11, b = 102.62, and c = 143.26 A. The orientation and position of the thrombin component was determined by molecular replacement and the hirudin molecule was fit in 2 magnitude of Fo - magnitude of Fc electron density maps. The structure was refined by restrained least squares and simulated annealing to R = 0.161 at 2.8-A resolution. The binding of hirudin to thrombin is generally similar to that observed in the crystals of human thrombin-hirudin. Several differences in …

The Cpce And Cpcf Genes Of Synechococcus Sp. Pcc 7002. Construction And Phenotypic Characterization Of Interposon Mutants, J Zhou, G E. Gasparich, V L. Stirewalt, R De Lorimier, D A. Bryant

Gail Gasparich

Isolation And Characterization Of The Triiodothyronine Regulatory Region Of The Fatty Acid Synthase Gene In Avian Species, Delfina Rivera Valencia

Masters Theses

Fatty acids are utilized for energy storage in the form of triglycerides or neutral fats. One way to regulate fatty acid biosynthesis is to regulate the activity of fatty acid synthase (FAS), the enzyme that catalyzes the reaction. Previous studies have shown that regulation of FAS activity and synthesis is regulated by the hormone triiodothyronine, T₃, at the level of transcription. Thus, isolation and characterization of the promoter region o f the FAS gene will enable the identification of the thyroid hormone response elements (TREs). This study could shed light on the mechanisms on how this gene can …

Saccharomyces Cerevisiae Sec59 Cells Are Deficient In Dolichol Kinase Activity, Loree Heller, Peter Orlean, W. Lee Adair Jr.

Bioelectrics Publications

The temperature-sensitive Saccharomyces cerevisiae mutant sec59 accumulates inactive and incompletely glycosylated protein precursors in its endoplasmic reticulum at the restrictive temperature. O-mannosylation and glycosyl phosphatidylinositol membrane anchoring of protein are also abolished, consistent with a deficiency in dolichyl phosphate mannose. Membranes prepared from sec59 cells that had been shifted to the restrictive temperature, however, made normal amounts of dolichyl phosphate mannose when exogenous dolichyl phosphate was supplied, but dolichyl phosphate mannose synthesis was severely depressed in the absence of exogenous dolichyl phosphate. Quantitative measurements of dolichyl phosphate in sec59 cells showed that the levels were decreased to 48% of wild …

The Structure Of Residues 7-16 Of The Aɑ-Chain Of Human Fibrinogen Bound To Bovine Thrombin At 2.3 Å Resolution, Philip D. Martin, William Robertson, Dusan Turk, Robert Huber, Wolfram Bode, Brian Fp Edwards

Biochemistry and Molecular Biology Faculty Publications

The tetradecapeptide Ac-D-F-L-A-E-G-G-G-V-R-G-P-R-V-OMe, which mimics residues 7f-20f of the A alpha-chain of human fibrinogen, has been co-crystallized with bovine thrombin from ammonium sulfate solutions in space group P2(1) with unit cell dimensions of a = 83.0 A, b = 89.4 A, c = 99.3 A, and beta = 106.6 degrees. Three crystallographically independent complexes were located in the asymmetric unit by molecular replacement using the native bovine thrombin structure as a model. The standard crystallographic R-factor is 0.167 at 2.3-A resolution. Excellent electron density could be traced for the decapeptide, beginning with Asp-7f and ending with Arg-16f in the active …

Structural Changes That Accompany The Reduced Catalytic Efficiency Of Two Semisynthetic Ribonuclease Analogs, V. Srini J. De Mel, Philip D. Martin, Marilynn S. Doscher, Brian Fp Edwards

Biochemistry and Molecular Biology Faculty Publications

The structures of two catalytically defective semi-synthetic RNases obtained by replacing aspartic acid 121 with asparagine or alanine have been determined and refined at a resolution of 2.0 A (R = 0.186 and 0.172, respectively). When these structures are compared with the refined 1.8-A structure (R = 0.204) of the fully active aspartic acid-containing enzyme (Martin, P.D., Doscher, M.S., and Edwards, B. F. P. (1987) J. Biol. Chem. 262, 15930-15938), numerous and widespread changes, much greater in number and magnitude than the small structural variations noted previously between the semisynthetic complex and RNase A, are found to have occurred. These …

A New Family Of Heparin Binding Growth/Differentiation Factors: Differential Expression Of The Midkine (Mk) And Hb-Gam Genes During Mouse Development, Masaru Nakamoto, Shyuichiro Matsubara, Teruo Miyauchi, Hiroya Obama, Takashi Muramatsu

Biology Faculty Publications

MK (midkine) and HB-GAM (heparin-binding growth-associated molecule) constitute a new family of heparin-binding growth differentiation factors. The modes of expression of MK and HB-GAM during mouse development were quantitatively examined by mRNA hybridization. The following three distinct patterns of expression were observed in the brain/head region. On the 11th-13th days of gestation, MK was intensely, but HB-GAM relatively weakly expressed; on the 15th-19th days, both MK and HB-GAM expression became weaker; and in the neonatal period, HB-GAM was intensely expressed and MK expression increased slightly. The level of HB-GAM expression was lower than that of MK in the whole embryo …

Glossary For Chemists Of Terms Used In Biotechnology, B. Nagel, H. Dellweg, Lila Gierasch

Lila Gierasch

The glossary contains definitions and explanatory notes, if needed, of over 230 terms frequently used in publications in the multidisciplinary field of biotechnology. The glossary was developed as a step to help facilitate communication between chemists, chemical engineers, biologists and bioengineers and to make biotechnology and its methodologies more accessible to the chemical profession. The interrelation between chemistry, chemical engineering and the burgeoning areas of molecular biology will be especially important as chemical industrial processes begin to incorporate recombinant DNA techniques, for example. The range of terms includes microbiology, genetic engineering, biochemistry, molecular biology, biochemical engineering, bioprocessing and general concepts …

Association Of Tetrapyrrole Intermediates In The Bacteriochlorophyll A Biosynthetic Pathway With The Major Outer-Membrane Porin Protein Of Rhodobacter Capsulatus, David Bollivar

Scholarship

No abstract provided.

Nucleotide Sequence Of S-Adenosyl-L-Methionine: Magnesium Protoporphyrin Methyltransferase From Rhodobacter Capsulatus, David Bollivar

Scholarship

No abstract provided.

Cytophotometric Estimation Of Nuclear Dna Content Variation In Ten Species Of Geniculate Coralline Algae (Corallinaceae, Rhodophyta), Jeffrey Craig Bailey

Dissertations, Theses, and Masters Projects

No abstract provided.

The Cγ Subunit Is A Unique Isozyme Of The Camp-Dependent Protein Kinase, Stephen J. Beebe, Paul Salomonsky, Tore Jahnsen, Yixin Li

Bioelectrics Publications

There are at least three isozymes (Cα, Cβ, and Cγ) of the mammalian catalytic (C) subunit of cAMP-dependent protein kinase (PKA) (Beebe, S., Oyen, O., Sandberg, M., Froysa, A., Hansson, V., and Jahnsen, T. (1990) Mol. Endocrinol. 4, 465-475). To compare the Cγ and Cα isozymes, the respective cDNAs were expressed in permanently transformed Kin-8 PKA-deficient Y1 adrenal cells using the mouse metallothionein promoter. The recombinant C subunits were characterized as immunoreactive, zinc-inducible, cAMP-dependent kinase activities. In contrast to Cα, histone was a better substrate than Leu-Arg-Arg-Ala-Ser-Leu-Gly (Kemptide) for Cγ. Furthermore, Cγ histone kinase activity was not inhibited by the …

Association Of Tetrapyrrole Intermediates In The Bacteriochlorophyll A Biosynthetic Pathway With The Major Outer-Membrane Porin Protein Of Rhodobacter Capsulatus, David W. Bollivar, Carl E. Bauer

David Bollivar

Rhodobacter capsulatus regulates synthesis of bacteriochlorophyll a in response to changes in oxygen partial pressure and light intensity. One early model proposed that this regulation involved a carrier polypeptide that functions to tether tetrapyrrole intermediates to the membrane. In the present study we isolated tetrapyrrole intermediates accumulated in three strains of R. capsulatus that contain mutations which block bacteriochlorophyll a biosynthesis at different steps of the magnesium branch of the pathway. Each of the tetrapyrrole intermediates was shown to be associated with the same 32 kDa polypeptide, as indicated by similar electrophoretic mobility and antigenic cross-reactivity with polyclonal antisera. The …

Nucleotide Sequence Of S-Adenosyl-L-Methionine: Magnesium Protoporphyrin Methyltransferase From Rhodobacter Capsulatus, David W. Bollivar, Carl E. Bauer

David Bollivar

No abstract provided.