scholarly journals CHEMICAL STUDIES ON A BASIC PEPTIDE PREPARATION DERIVED FROM CALF THYMUS

1954 ◽  
Vol 99 (1) ◽  
pp. 65-78 ◽  
Author(s):  
James G. Hirsch ◽  
René J. Dubos
Keyword(s):  
Amino Acids ◽  
Antimycobacterial Activity ◽  
Homogeneous State ◽  
Basic Peptide ◽  
Calf Thymus ◽  
Chemical Studies ◽  
Cellulose Membranes ◽  
Basic Peptides ◽  
Peptide Preparation

A substance possessing antimycobacterial activity under certain conditions in vitro has been prepared from aqueous extracts of calf thymus. Chemical studies have demonstrated that the activity of this substance is due to a basic peptide or a mixture of basic peptides. Although this thymus fraction has been shown to be essentially free of compounds other than peptides, it has not been obtained in a homogeneous state. The thymus peptide preparation is soluble in water and in the lower alcohols. Its solubility is minimal between pH 10 and 11, suggesting that its isoelectric point may be in this vicinity. The microbiological activity of thymus peptide is destroyed by acid or alkaline hydrolysis and also by trypsin digestion, but is unaffected by pepsin digestion. Cellulose membranes are permeable to thymus peptide. The most noteworthy finding concerning the amino acid composition of thymus peptide is the preponderance of the basic amino acids lysine and arginine, which together account for about 40 per cent of the weight of this substance. No cystine, and only trace amounts of other amino acids containing sulfur, are present in the thymus peptide preparation.

scholarly journals THE ANTIMYCOBACTERIAL ACTIVITY OF A PEPTIDE PREPARATION DERIVED FROM CALF THYMUS

1954 ◽  
Vol 99 (1) ◽  
pp. 55-63 ◽  
Author(s):  
René J. Dubos ◽  
James G. Hirsch
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Antimycobacterial Activity ◽  
Water Soluble ◽  
Enzymatic Hydrolysate ◽  
Calf Thymus ◽  
Water Soluble Substance ◽  
Peptide Preparation ◽  
Sheep Thymus

A stable, water-soluble substance which possesses potent antimycobacterial activity under certain conditions in vitro has been prepared from calf thymus. This substance has been tentatively named thymus peptide. In final concentrations of 1 to 10 µg. per ml. of an albumin medium it inhibits the growth of various strains of mammalian mycobacteria, but manifests only little or no inhibitory activity against a variety of other microbial species. The ability of thymus peptide to inhibit the multiplication of tubercle bacilli diminishes when the inoculum is large, or when the medium is acidic. It is also markedly antagonized by addition of enzymatic hydrolysate of casein or beef heart infusion broth to the culture medium. Thymus peptide does not exert a rapid bactericidal action on tubercle bacilli, but organisms exposed to this compound for longer than 2 weeks could not be made to multiply in ordinary culture media. Substances similar or identical to the thymus peptide preparation could be extracted from calf spleen, sheep thymus, beef lymph nodes, and calf pancreas, but not from calf lung or calf liver.

scholarly journals MECHANISMS INVOLVED IN THE ANTIMYCOBACTERIAL ACTIVITY OF CERTAIN BASIC PEPTIDES

1954 ◽  
Vol 99 (1) ◽  
pp. 79-88 ◽  
Author(s):  
James G. Hirsch
Keyword(s):  
Adrenocorticotropic Hormone ◽  
Sulfur Metabolism ◽  
Antimycobacterial Activity ◽  
Posterior Pituitary ◽  
Animal Tissues ◽  
Sulfate Ions ◽  
Basic Peptide ◽  
Posterior Pituitary Gland ◽  
Basic Peptides

The antimycobacterial activity of thymus peptide under certain conditions in vitro can be partially neutralized by increasing the concentration of sulfate ions in the medium, and to a lesser extent by the addition of certain organic compounds which contain sulfur. It is suggested that thymus peptide suppresses the growth of tubercle bacilli by interfering with the normal sulfur metabolism of these microorganisms. Polylysine peptide and pituitary adrenocorticotropic hormone, other basic peptides derived from animal tissues, also inhibit the multiplication of tubercle bacilli in vitro, and their antimycobacterial activity is also antagonized by sulfate ions. Basic peptide hormones prepared from the posterior pituitary gland do not affect the growth of acid-fast bacteria under the conditions of the test.

scholarly journals Experimental and computational studies of an antiplasmodial derivative of allantoin; antimycobacterial essential oil from Cordia batesii WERNHAM (Boraginaceae)

BMC Chemistry ◽  
2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Eric Robert Tiam ◽  
Dominique Serge Ngono Bikobo ◽  
Ibrahim Mbouombouo Ndassa ◽  
Norbert Mbabi Nyemeck II ◽  
Auguste Abouem A Zintchem ◽  
...  
Keyword(s):  
Essential Oil ◽  
Density Functional ◽  
Chemical Shifts ◽  
Antimycobacterial Activity ◽  
Functional Theory ◽  
Oil Fraction ◽  
Chemical Studies ◽  
Oil Density ◽  
Mycobacterial Strain

Abstract Background Chemical and pharmacological investigations were performed on the stems of Cordia batesii (Boraginaeae); chemical studies included quantum calculations applied on a newly described compound. Results A new derivative of allantoin (1) named batesiin (2) was characterized. Thirteen other known compounds involving allantoin (1) were either isolated or identified. GC–MS enabled the identification of six compounds from a fraction containing essential oil. MeOH extract and some isolated compounds were tested in vitro against Pf7G8 CQS and Pf Dd2 CQR strains of Plasmodium falciparum; extract disclosed a moderate antiplasmodial activity (IC50 = 50 μg mL−1). Meantime, the CH2Cl2 extract and essential oil fraction were tested on a resistant mycobacterial strain of Mycobacterium tuberculosis; a potent antimycobacterial activity with a MIC = 9.52 μg mL−1 was deduced from essential oil. Density functional theory (DFT) calculations were carried on batesiin (2). Calculated chemical shifts at B3LYP/6-31G(d,p) and MPW1PW91/6-31G+(d,p) showed much better correlations with the experimental data. Time dependent DFT at B3LYP/6-31G+(d,p) displayed a major absorption band 3.01 nm higher than the experimental value. Conclusion Cordia batesii can be considered as promising in search of compounds with antimalarial and antitubercular properties. DFT studies are very helpful when trying to learn more about the spectroscopic insights of a derivative of allantoin (1).

Torus Circumference and Thickness Parameters From a Linear DNA Size Series Suggest How Toruses Self-Assemble

1985 ◽  
Vol 43 ◽  
pp. 522-523
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx
Keyword(s):  
Tertiary Structure ◽  
Dna Complexes ◽  
Tertiary Structures ◽  
Self Assembling ◽  
Double Stranded Dna ◽  
Calf Thymus ◽  
Dna Organization ◽  
Condensed Dna ◽  
Dna Size

Certain double stranded DNA bacteriophage and viruses are thought to have their DNA organized into large torus shaped structures. Morphologically, these poorly understood biological DNA tertiary structures resemble spermidine-condensed DNA complexes formed in vitro in the total absence of other macromolecules normally synthesized by the pathogens for the purpose of their own DNA packaging. Therefore, we have studied the tertiary structure of these self-assembling torus shaped spermidine- DNA complexes in a series of reports. Using freeze-etch, low Pt-C metal (10-15Å) replicas, we have visualized the microscopic DNA organization of both calf Thymus( CT) and linear 0X-174 RFII DNA toruses. In these structures DNA is circumferentially wound, continuously, around the torus into a semi-crystalline, hexagonal packed array of parallel DNA helix sections.

Antimyotoxic Activity of Synthetic Peptides Derived from Bothrops atrox Snake Gamma Phospholipase A2 Inhibitor Selected by Virtual Screening

2019 ◽  
Vol 19 (22) ◽  
pp. 1952-1961 ◽  
Author(s):  
J.C. Sobrinho ◽  
A.F. Francisco ◽  
R. Simões-Silva ◽  
A.M. Kayano ◽  
J.J. Alfonso Ruiz Diaz ◽  
...  
Keyword(s):  
Amino Acids ◽  
Molecular Docking ◽  
Synthetic Peptides ◽  
Cell Damage ◽  
Neutralization Assay ◽  
Phospholipase Activity ◽  
Phospholipases A2 ◽  
Catalytically Active ◽  
Bothrops Atrox

Background: Several studies have aimed to identify molecules that inhibit the toxic actions of snake venom phospholipases A2 (PLA2s). Studies carried out with PLA2 inhibitors (PLIs) have been shown to be efficient in this assignment. Objective: This work aimed to analyze the interaction of peptides derived from Bothrops atrox PLIγ (atPLIγ) with a PLA2 and to evaluate the ability of these peptides to reduce phospholipase and myotoxic activities. Methods: Peptides were subjected to molecular docking with a homologous Lys49 PLA2 from B. atrox venom modeled by homology. Phospholipase activity neutralization assay was performed with BthTX-II and different ratios of the peptides. A catalytically active and an inactive PLA2 were purified from the B. atrox venom and used together in the in vitro myotoxic activity neutralization experiments with the peptides. Results: The peptides interacted with amino acids near the PLA2 hydrophobic channel and the loop that would be bound to calcium in Asp49 PLA2. They were able to reduce phospholipase activity and peptides DFCHNV and ATHEE reached the highest reduction levels, being these two peptides the best that also interacted in the in silico experiments. The peptides reduced the myotubes cell damage with a highlight for the DFCHNV peptide, which reduced by about 65%. It has been suggested that myotoxic activity reduction is related to the sites occupied in the PLA2 structure, which could corroborate the results observed in molecular docking. Conclusion: This study should contribute to the investigation of the potential of PLIs to inhibit the toxic effects of PLA2s.

The 1- and 2-Naphthylalanine Analogs of Oxytocin and Vasopressin

1995 ◽  
Vol 60 (12) ◽  
pp. 2170-2177 ◽  
Author(s):  
Zdenko Procházka ◽  
Jiřina Slaninová
Keyword(s):  
Amino Acids ◽  
Solid Phase ◽  
Pressor Test

Solid phase technique on p-methylbenzhydrylamine resin was used for the synthesis of four analogs of oxytocin and four analogs of vasopressin with the non-coded amino acids L- or D- and 1- or 2-naphthylalanine and D-homoarginine. [L-1-Nal2]oxytocin, [D-1-Nal2]oxytocin, [L-2-Nal2]oxytocin, [D-2-Nal2]oxytocin, [L-1-Nal2, D-Har8]vasopressin, [D-1-Nal2, D-Har8]vasopressin, [L-2-Nal2, D-Har8]vasopressin and [D-2-Nal2, D-Har8]vasopressin were synthesized. All eight analogs were found to be uterotonic inhibitors in vitro and in vivo. Analogs with 2-naphthylalanine are stronger inhibitors, particularly in the vasopressin series than the analogs with 1-naphthylalanine. Analogs with 1-naphthylalanine have no activity in the pressor test, analogs with 2-naphthylalanine are weak pressor inhibitors.

Relations between Structure and Antituberculotic Activity of 4-Alkoxybenzoic Acids

1993 ◽  
Vol 58 (1) ◽  
pp. 191-196 ◽  
Author(s):  
Karel Waisser ◽  
Jiří Kuneš ◽  
Jiří Klimeš ◽  
Miroslav Polášek ◽  
Želmíra Odlerová
Keyword(s):  
Active Compound ◽  
Antimycobacterial Activity ◽  
Methoxybenzoic Acid

Antimycobacterial activity of a series of alkoxybenzoic acids including 4-methoxybenzoic acid (II), 4-ethoxybenzoic acid (III), 4-propoxybenzoic acid (IV), 4-butoxybenzoic acid (V), 4-pentoxybenzoic acid (VI), 4-allyloxybenzoic acid (IX), 4-isopropoxybenzoic acid (VII), 4-isobutoxybenzoic acid (VIII) and 4-benzyloxybenzoic acid (X) has been determined and found to increase with the lipophilicity of the compounds expressed by the corresponding HPLC capacity factors. Also determined were the pKa values of the compounds mentioned. The most active compound, 4-pentoxybenzoic acid (VI), is comparable with commercial antituberculotics when tested in vitro.

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