Barstar Inhibits Extracellular Ribonucleases of Streptomyces and
Allows their Production from Recombinant Genes. Pp. 225-231.
Robert W. Hartley, Valentin Both, Eric J. Hebert, Dagmar Homerova,
Milan Jucovic, Viktor Nazarov, Igor Rybajlák and Jozef
Sevcik
[Abstract]
Mutagenesis of Recombinant Human Fibroblast Stromelysin C-Terminus
Reveals the Autodegradation Pathway. Pp. 233-240.
M. Walid Qoronfleh, Thau Ho, Tracey Banks, Tricia Pulvino,
Patricia Brake, Richard Ciccarelli, Jim Koehn, James Huang and
Robert Wahl
[Abstract]
Folding Behaviour of Retro-Rubredoxin. Pp. 241-246.
Menotti Ruvo and Giogio Fassina
[Abstract]
Isolation and in vitro Cleavage Specificities of Epidermal
Growth Factor Binding Proteins. Pp. 247-252.
Obaid U. Beg and Mukarram Uddin
[Abstract]
Combinatorial Chemistry and Natural Products: Determination of
the Biological Activity of On-Bead, Double Cleavable Teicoplanin
aglycone (TD). Pp. 253-260.
Christine F. Sizemore, Pierfausto Seneci, Petr Kocis, Kenneth
F. Wertman and Khalid Islam
[Abstract]
Stimulation of Non-Specific Resistance by Human Casein Fragment
(54-59) and its Synthetic Analogues Against Leishmania donovani
Infection. Pp. 261-266.
P. Sharma, Anuradha, R. Sharan, W. Haq, B. Kundu, J.C. Katiyar
and K.B. Mathur
[Abstract]
Complete Amino Acid Sequences of Two gamma-Thionins from Maize (Zea
mays L.) Seeds. Pp. 267-274.
Mariana de Souza Castro, Wagner Fontes, Lauro Morhy and Carlos
Bloch Jr.
[Abstract]
Conformational Behaviour of an Analogue of the S-Peptide: A Molecular
Dynamics Study. Pp. 275-282.
Vincenzo Abruscato, Graziella Ranghino and Anna Maria-Villa
[Abstract]
Crystallisation Report
Crystal-State Structure of the C-Terminal Pentapeptide of the
Antibiotic Efrapeptin C. Pp. 283-288.
Fernando Formaggio, Vittorio Moretto and Claudio Toniolo
[Abstract]
Crystallization and Preliminary Characterization of Shigella boydii
DGTP-Triphosphohydrolase. Pp. 289-292.
Stephen Quirk
[Abstract]
[Back to top] ORTHOGONALLY PROTECTED N-METHYL-SUBSTITUTED
ALPHA-AMINOGLYCINES, Guangcheng Jiang, Lajos Simon, and Jean E. Rivier.
Title glycine derivatives FmocNR1CH(NR2Boc)CO2H (I; Fmoc = 9-fluorenyl-methyloxycarbonyl; Boc = Me3CO2C; R1 = H, Me; R2 = H, Me), useful as templates for the introduction of desired functionalities into peptides, were prepared by condensation of glyoxylic acid and carbamates Fmoc-NH-R1 (R1 = H, Me), followed by conversion with Me2CHSH of the resulting FmocNR1CH(OH)CO2H to FmocNR1CH(SCHMe2)CO2H (R1 = H, Me) which were further treated with Boc-NH-R2 (R2 - H, Me) in the presence of N-bromosuccinimide. A simple and efficient synthesis of Fmoc-NH-Me and Boc-NH-Me is also reported.
[Back to top] BARSTAR INHIBITS EXTRACELLULAR RIBONUCLEASES OF STREPTOMYCES AND ALLOWS THEIR PRODUCTION FROM RECOMBINANT GENES, Robert W. HartIey, Valentin Both, Eric J. Hebert, Dagmar Homerova, Milan Jucovic,
Viktor Nazarov, Igor Rybajlak and Jozef Sevcik.
Barstar, the intracellular protein of Bacillus amyloliquefaciens which binds to and inhibits barnase, the extracellular ribonuclease of the same organism, has been found to bind to and inhibit also the homologous ribonucleases of several Streptomyces strains. The ribonucleases of four strains of Streptomyces have been produced from recombinant or synthetic genes on plasmid vectors in E. coli. Sequence identity among these enzymes is from 49 % to 69 %. Sequence identities to barnase are no more than 25 %.
[Back to top] MUTAGENESIS OF RECOMBINANT HUMAN FIBROBLAST STROMELYSIN C-TERMINUS REVEALS THE AUTODEGRADATION PATHWAY, M. Walid Qoronfleh, Thau Ho, Tracey Banks, Tricia Pulvino, Patrida Brake, Richard Ciccarelli,
Jim Koehn, James Huang, and Robert Wahl.
Stromelysin as a member of the matrix metalloproteinases (MMP) family participates in connective tissue remodeling and diseases. Understanding MMPs' catalytic mechanism and designing specific inhibitors to control their activity is of great interest. A clone for mature truncated stromelysin (SL), F83 to T260, without the C-terminal hemopexin-like domain was constructed and expressed in E. coli. The purified, recombinant protein was active and had a specific activity and Ki values comparable to that of the native enzyme. However, protein degradation was observed which was attributed to autolysis. A specific autolytic site at S244-L245 was identified by N-terminal sequencing. A series of SL muteins and new truncations were engineered to evaluate their effects on autolysis. The replacement of L245 with an R prevents the autodegradation of SL at the S244-L245 autolytic site. This substitution reveals the primary site initiating SL autolysis (self-catalyzed cleavage) and locates it at V163-L164.
[Back to top] FOLDING BEHAVIOUR OF RETRO-RUBREDOXIN, Menotti Ruvo and Giorgio Fassina.
The hypothesis that retro proteins should adopt conformations similar to that of the parent protein has been tested by preparing the retro derivative of (Ala 31) rubredoxin, a 45 residue polypeptide that is able to adopt stable structures in solution and displaying affinity for bivalent metal ions. Circular dichroism and UV measurements indicated that while the synthetic rubredoxin mutant acquired the typical conformation and iron binding ability in solution, the retro derivative did not show any evidence of structure nor of iron binding activity.
[Back to top] ISOLATION AND in vitro CLEAVAGE SPECIFICITIES OF EPIDERMAL GROWTH FACTOR BINDING PROTEINS, Obaid U. Beg and Mukarram Uddin.
Results of the present investigation indicate the presence of three mouse epidermal growth factor binding proteins (EGF-BP-A, -B and -C) in BPN strain of mice. MI of these proteases show specificity towards Arg-Val and Tyr-Ser bonds which appears, inpart, to be dependent on adjacent arnino acids.Additionally EGF-BP-A also cleaves Lys-Val and Leu-Ser bonds; BGF-BP-B cleaves Lys-Ala bond and EGF-BP-C cleaves Lys-Val and Lys-Ala bonds.These cleavages distinguish EGF-BP's from each other.
[Back to top] COMBINATORIAL CHEMISTRY AND NATURAL PRODUCTS: DETERMINATION OF THE BIOLOGICAL ACTIVITY OF ON-BEAD, DOUBLE CLEAVABLE TEICOPLANIN AGLYCONE (TD), Christine F. Sizemore, Pierfausto Seneci, Petr Kocis, Kenneth F. Wertman, and Khalid Islam.
Teicoplanin aglycone (TD), a derivative of the naturally occurring antibiotic, was coupled to Tentagel resin beads using a releasable linker technique. The biological properties of the compound were examined in growth inhibition assays after cleavage of the linker under different pH conditions. The results show that combinatorial techniques on solid-phase can be used for large, complex molecules, and that the biological method described may be generally useflil for high volume screening of large combinatorial chemical libraries.
[Back to top] STIMULATION OF NON-SPECIFIC RESISTANCE BY HUMAN CASEIN FRAGMENT(54-59) AND ITS SYNTHETIC ANALOGUES AGAINST LEISHMANIA DONOVANI INFECTION, P. Sharma, Anuradha, R. Sharan, W. Haq, B. Kundu, J.C. Katiyar and K.B. Mathur
The prophylactic effect of human beta casein fragment (54-59) and its synthetic congeners has been studied against L. donovani infection in hamsters. Maximum parasite inhibition (84%) was observed with compound 4. The activity of this compound was further confirmed in vitro.
[Back to top] COMPLETE AMINO ACID SEQUENCES OF TWO gamma-THIONINS FROM MAIZE (Zea mays L.) SEEDS, Mariana de Souza Castro, Wagner Fontes, Lauro Morhy and Carlos Bloch Jr.
Two gamma-thionins were purified from maize (Zea mays L.) seeds by saline extraction, ainmonium sulfate precipitation, pseudo-affinity and RP-HPLC chromatographies. Their complete amino acid sequences were determined by automated Edman degradations of the intact and S-alkylated proteins and peptides obtained from proteolytic digests and confirmed by ES/MS analysis. These sequences show remarkable homology with sorghum alpha-amylase isoinhibtors.
[Back to top] CONFORMATIONAL BEHAVIOUR OF AN ANALOGUE OF THE S-PEPTIDE: A MOLECULAR DYNAMICS STUDY, Vincenzo Abruscato, Graziella Ranghino, Anna Maria Villa
The S-peptide, derived from the hydrolysis of Ribonuclease, is a stable alpha-helix in water, although it is only 20 amino acids long. In view of increasing the helical content and stability, a mutated sequence has been proposed. The present work aims to shed light on the conformational preferences and on the helix stability of the proposed sequence by means of Molecular Dynamics simulations performed with different procedures.
[Back to top] CRYSTAL-STATE STRUCTURE OF THE C-TERMINAL PENTAPEPTIDE OF THE ANTIBIOTIC EFRAPEPTIN C, Ettore Benedetti, Rosa lacovino, Michele Saviano, Johan Kamphuis, Marco Crisma, Fernando Formaggio, Vittorio Moretto and Claudlo Toniolo.
An X-ray diffraction analysis of the C-terminal, fully blocked pentapeptide segment of the antibiotic efrapeptin C Z-L-Pip-Aib-G1y-L-Leu~Aib~NHMe monohydrate showed that its secondary structure is characterized by three non-helical beta-bend conformations located at the -L-Pip-Aib-, -Aib-Gly-, and -L-Leu-Aib- sequences, respectively.
[Back to top] CRYSTALLIZATION AND PRELIMINARY CHARACTERIZATION OF SHIGELLA BOYDII DGTP TRIPHOSPHOHYDROLASE, Stephen Quirk.
The enzyme deoxyguanosine triphosphatetriphosphohydrolase from Shigella boydii has been crystallized by the vapor diffusion method using 2-methyl-2,4-pentanediol and calcium chloride in sodium acetate buffer (pH4.5). The monoclinic crystals belong to space group P2(1) and have unit cell dimensions a = 157.2 A, b = 74.8 A, c = 93.1 A, and beta = 91.6 o. Thecrystals diffract to 3.0 A resolution, and there is one 237.6 kDa enzymetetramer per asymmetric unit. The crystals have a solvent content of 47%.