38 research outputs found
Cadmium-thionein in Tetrahymena thermophila and Tatrahymena pyriformis.
No full textSummary: The treatment of Tetrahymena thermophila with cadmium causes a reduction in growth rate according to dose; almost all the metal is accumulated in the cytosol where the Zn content is also increased threefold.
Bio-Gel and Water 160 (HPLC) column chromatography show that Cd and Zn are bound to a protein with an ultraviolet (UV) spectrum that appears to be similar to that of Cd-metallothioneins isolated by higher organisms, but its molecular weight is greater: about 28 000 D, comparable to that of metallothionein isolated from Tetrahymena pyriformis.
Further purification of these proteins by ion exchange chromatography revealed the presence of two peaks, considered as two isoforms of the metallothioneins present in both T. thermophila and T. pyriformis (MT 1 and MT 2). Their amino acid analyses confirmed that they are different isometallothioneins, MT 1 and MT 2, with about 30% cysteine, and aspartic acid, glycine and lysine as major amino acids. From our analyses we may conclude that Tetrahymena pyriformis MTs are similar to those present in invertebrates and vertebrates, while Tetrahymena thermophila MTs are peculiar in that they have cyclic amino acid histidine in both MT 1 and MT 2; furthermore, aromatic amino acid phenylalanine is also present in MT 2
Evoluzione molecolare delle metallotioneine nei teleostei antartici: analisi filogenetica basata sulle 3' UTR
No full textEffects of Cadmium in Stylonychia lemnae, Stylonychia notophora and Oxytricha granulifera: Isolation of a Cadmium-Binding Protein
No full text"La mia cara Cecchina è baronessa": livelli stilistici e assetto drammaturgico ne “La buona figliuola” di Goldoni-Piccinni
No full textLo studio propone un'analisi drammaturgico-musicale della Buona figliuola di Goldoni-Piccinni dimostrando l'esistenza di una efficace e studiata strategia compositiva atta ad assecondare e valorizzare le indicazioni drammaturgiche allestite dell'autore del testo poetico.The study provides an analysis of the musical-dramatic daughter of Goldoni Good-Piccinni proving the existence of an effective and studied musical composition adapted to accommodate and enhance the signs of drama staged the author of the poetic text
Parallelizations on products of spheres and octonionic geometry
No full textA classical theoremof Kervaire states that products of spheres are parallelizable if and only if at least one of the factors has odd dimension. Two explicit parallelizations on S^m × S^{2h−1} seem to be quite natural, and have been previously studied by the first named author. The present paper is devoted to the three choices G = G_2, Spin(7), Spin(9) of G-structures on S^m × S^{2h−1}, respectively with m + 2h − 1 = 7, 8, 16 and related with octonionic geometry
Characterization and transcription studies of a phytochelatin synthase gene from the solitary tunicate Ciona intestinalis exposed to cadmium
No full textThe major thiol-containing molecules involved in controlling the level of intracellular ROS in eukaryotes, acting as a nonenzymatic detoxification system, are metallothioneins (MTs), glutathione (GSH) and phytochelatins (PCs). Both MTs and GSH are well-known in the animal kingdom. PC was considered a prerogative of the plant kingdom but, in 2001, a phytochelatin synthase (PCS) gene was described in the nematode Caenorhabditis elegans; additional genes encoding this enzyme were later described in the earthworm Eisenia fetida and in the parasitic nematode Schistosoma mansoni but scanty data are available, up to now, for Deuterostomes. Here, we describe the molecular characteristics and transcription pattern, in the presence of Cd, of a PCS gene from the invertebrate chordate Ciona intestinalis, a ubiquitous solitary tunicate and demonstrate the presence of PCs in tissue extracts. We also studied mRNA localization by in situ hybridization. In addition, we analyzed the behavior of hemocytes and tunic cells consequent to Cd exposure as well as the transcription pattern of the Ciona orthologous for proliferating cell nuclear antigen (PCNA), usually considered a proliferation marker, and observed that cell proliferation occurs after 96 h of Cd treatment. This matches the hypothesis of Cd-induced cell proliferation, as already suggested by previous data on the expression of a metallothionein gene in the same animal
Parallelizations on products of spheres and octonionic geometry
No full textA classical theoremof Kervaire states that products of spheres are parallelizable if and only if at least one of the factors has odd dimension. Two explicit parallelizations on Sm × S2h−1 seem to be quite natural, and have been previously studied by the first named author in [32]. The present paper is devoted to the three choices G = G2, Spin(7), Spin(9) of G-structures on Sm × S2h−1, respectively with m + 2h − 1 = 7, 8, 16 and related with octonionic geometry
