Semiempirical AM1 and ab initio parameters of the lethal cyclopeptides α-amanitin and its related thioether, S-sulphoxide, sulphone, and O-methyl derivative

Pomilio, Alicia B.; Battista, Miguel Edgardo; Vitale, Arturo A.

doi:10.1016/s0166-1280(00)00638-2

Cited by 4 publications

(9 citation statements)

References 32 publications

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“…According to these calculations [122], the planar indole moiety is ahead from the rest of the bean-shaped bicyclic structure (Fig. (41)).…”

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 97%

“…(40)) were obtained for the first time from molecular parameters on the basis of AM1 and ab initio methods [122]. Stereochemical changes, total energy, mapped electrostatic potentials, molecular orbital calculations and dipole moments were calculated [122]. Both semiempirical and ab initio methods have been compared, showing to be in good agreement.…”

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 99%

“…Therefore, the cavity was negative, nucleophilic, and thus adequate for scavenging cations in order to form complexes with probably a high stability constant. Inclusion of molecules was also possible taking into account the size of this cavity in each case, the largest being nearly 10 Å, and the others in the range 6-8 Å [122].…”

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 99%

“…Total and point-charge dipole moments and sp hybrid were calculated for ((111), (127)-(130)) and were given as a vector in three dimensions [122]. By convention, the dipole moment pointed in the direction of positive charge, as indicated for each compound in Fig.…”

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 99%

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Naturally-Occurring Cyclopeptides: Structures and Bioactivity

Pomilio¹,

Battista²,

Vitale

2006

COC

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Cyclic peptides are a special bioactive group of compounds with interesting pharmacological and biochemical properties. Different natural sources are mentioned in this paper, but interest is focused on those cyclopeptides isolated from higher plants and higher fungi. Cyclopeptides occur in higher plant species, which belong to the following families: Annonaceae, Araliaceae, Asteraceae, Caryophyllaceae, Euphorbiaceae, Fabaceae, Labiatae, Linaceae, Olacaceae, Rhamnaceae, Rubiaceae, Rutaceae, Schizandraceae, Solanaceae, and Violaceae. Basidiomycetes is the group of higher fungi, which has shown to be rich in cyclopeptides, e.g., Amanita, Conocybe, Lepiota, Galerina, and Omphalotus species. Usually these compounds are associated to a toxic response in mammals, as well as to cytotoxic, insecticidal, antimalarial, estrogenic, sedative, nematicidal, antimicrobial, immunosuppressive, and enzyme-inhibitory activities. Structures are elucidated by chemical methods and spectroscopic techniques. Configurational and conformational analyses of some bioactive cyclopeptides are discussed. Conformational studies of the natural cyclopeptides and their derivatives are related to the stereochemical requirements for these bioactive compounds.

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“…According to these calculations [122], the planar indole moiety is ahead from the rest of the bean-shaped bicyclic structure (Fig. (41)).…”

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 97%

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 99%

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 99%

Section: Conformations Dipole Moments and Toxicitymentioning

confidence: 99%

See 2 more Smart Citations

Naturally-Occurring Cyclopeptides: Structures and Bioactivity

Pomilio¹,

Battista²,

Vitale

2006

COC

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“…The cycle peptide chain, α-amanitin, has eight amino acids: asparagine, hydroxyl proline, dihydroxy isoleucine, hydroxyl-mercapto-tryptophan, glycine, isoleucine, glycine and alanine. Hydroxyl proline and dihydroxy isoleucine activate RNA polymerase II and III by binding to the enzyme molecule, enhancing the activating effect by means of glycine and isoleucine binding [6][7][8]. The immediate cause of death from mushroom poisoning is kidney, liver and respiratory failure which occur within one week of ingestion.…”

Section: Introductionmentioning

confidence: 99%

Deactivation Study of α-Amanitin Toxicity in Poisonous Amanita spp. Mushrooms by the Common Substances In Vitro

Narongchai¹,

Narongchai²

2017

J Forensic Res

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The purpose of this research was to find out the substance which deactivate α-Amanitin ToxicityThe materials and methods used in the study include analysis with high performance liquid chromatography (HPLC) to:1.Demonstrate the standard α-amanitin at concentrations of 25, 50 and 100 µg/ml 2.Determine the deactivation of α-amanitin with 1) 18% acetic acid 2), calcium hydroxide 40 mg/ml, 3) potassium permanganate 20 mg/ml, 4) sodium bicarbonate 20 mg/ml 3.Report the statistical analysis as the mean ± standard deviation (SD) and paired t-test.The result revealed that potassium permanganate could eliminate 100 percent of the α-amanitin at 25, 50 and 100 µg/ml. Calcium hydroxide, sodium bicarbonate and acetic acid had lower elimination rates at those concentrations: 68.43 ± 2.58 (-71.4, -67.2, -66.7%), 21.48 ± 10.23 (-29.4, -25.2, -9.9%) and 3.21 ± 0.02% (-3.2, -3.2, +1.1%), respectively. The conclusion of this study was suggested that potassium permanganate could be applied as an absorbent substance during gastric lavage in patients with mushroom poisoning. It also might be effective as a cleansing wash for uncooked mushrooms. Investigation of potassium permanganate's ability to absorb α-amanitin in animal models and humans should be considered. .Patients with α-amanitin poisoning can develop severe toxic hepatitis, centrilobular necrosis, liver steatosis, and acute tubulointerstitial necrosis leading to hepatorenal syndrome all of which have a high mortality rate. The most effective treatment is emptying the stomach promptly by performing gastric lavage with 1:2,000 tannic acid or 1:10,000 potassium permanganase plus triggering emesis. A warm saline solution of potassium permaganase can be used as an emergency treatment to reduce toxins in the intestines and stomach. Thus, KMnO 4 , NaHCO 3 , Ca(OH) 2 and acetic acid should be considered as a cleanser for uncooked mushrooms to deactivate α-amanitin toxicity and potentially reduce the mortality rate from liver failure, acute renal failure, respiratory failure and gastro-intestinal haemorrhage [9]. Materials and MethodsIn this study, experiments were performed on α-amanitin at concentrations of 25, 50 and 100 µg/ml eached mixed with 1) 18% acetic acid 2), calcium hydroxide 40 mg/ml, 3) potassium permanganate 20 mg/ml, 4) sodium bicarbonate 20 mg/ml (results analyzed with high performance liquid chromatography (HPLC) with Luna C18 (150 × 4.6 mm I.D., 5 micron) from Phenomenex ® , USA), or 5) mobile phase (a mixture of 0.02 M aqueous ammonium acetate and acetonitrile (88/12, v/v) pH 5.0 at an absorbance of 280 nm). Glacial acetic acid was used to Citation: Narongchai P, Narongchai S (2017) Deactivation Study of α-Amanitin Toxicity in Poisonous Amanita spp. Mushrooms by the Common Substances In Vitro. J Forensic Res 8: 396.

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Computational Studies on Biphenyl Derivatives. Analysis of the Conformational Mobility, Molecular Electrostatic Potential, and Dipole Moment of Chlorinated Biphenyl: Searching for the Rationalization of the Selective Toxicity of Polychlorinated Biphenyls (PCBs)

Chana

Concejero

Frutos

et al. 2002

Chem. Res. Toxicol.

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With the objective to understand how the pattern and degree of chlorination influence on the properties of the title molecules, a computational study on biphenyl and all the chlorinated biphenyls (from 1 to 10 chlorine atoms, 209 congeners) has been undertaken. The study includes conformational searches (and further refinement by molecular dynamics simulations) and the ab initio calculation of the molecular electrostatic potential (MEP) and the dipole moments for all the congeners. The most significant property is the MEP, finding a good correlation between the MEPs and the substitution pattern on chlorinated biphenyls. The most toxic congeners possess highly positive values of electrostatic potential on the aromatic rings and highly negative values of electrostatic potential on the chlorine atoms. Additionally, we have found that the toxic congeners possess conformations with low dipole moments, a fact that may be linked to the ready accumulation on the adipose tissue. The results on the geometry and electrostatic properties of chlorinated biphenyls can be useful to rationalize their selective toxicities.

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Semiempirical AM1 and ab initio parameters of the lethal cyclopeptides α-amanitin and its related thioether, S-sulphoxide, sulphone, and O-methyl derivative

Cited by 4 publications

References 32 publications

Naturally-Occurring Cyclopeptides: Structures and Bioactivity

Naturally-Occurring Cyclopeptides: Structures and Bioactivity

Deactivation Study of α-Amanitin Toxicity in Poisonous Amanita spp. Mushrooms by the Common Substances In Vitro

Computational Studies on Biphenyl Derivatives. Analysis of the Conformational Mobility, Molecular Electrostatic Potential, and Dipole Moment of Chlorinated Biphenyl: Searching for the Rationalization of the Selective Toxicity of Polychlorinated Biphenyls (PCBs)

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