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The first nucleotide sequence of an archaeal elongation factor 1β gene
No full textAn archaeal elongation factor 1β gene has been isolated for the first time from a Sulfolobus solfataricus genomic library. The sequenced clone (869 bp) contained two open reading frames, one coding for a protein made of 91 amino acid residues (SsEF-1β), the other one encoding a nonidentified product (ORF 115). The amino acid sequences of segments at the N-and C-terminal of the translated SsEF-1β were identical to those determined for the native protein. Northern and Southern analyses showed that the SsEF-1β gene is represented in S. solfataricus by a unique sequence. Compared to eubacterial or eukaryal corresponding genes the SsEF-1β is much shorter
Expression in Escherichia coli of thermostable elongation factor 1 alpha from the archaeon Sulfolobus solfataricus
No full textThe elongation factor 1 alpha from the archaeon Sulfolobus solfataricus (SsEF-1 alpha) was expressed in Escherichia coli and purified. The SsEF-1 alpha gene was amplified by PCR and cloned in the Ndel site of the pT7-7 expression vector, under the control of the promoter of T7 RNA polymerase. Upon induction with isopropyl beta-D-thiogalactopyranoside, the recombinant SsEF-1 alpha (recSsEF-1 alpha) was purified from the E. coli S-100 extract by a two-step procedure. From 1 litre of cell culture, about 2 mg of purified recSsEF-1 alpha was obtained. The N-terminal sequence of the first 30 amino acid residues of recSsEF-1 alpha was identical with that translated from the nucleotide sequence of the corresponding gene, except for the initial residue, which in recSsEF-1 alpha was Ser instead of Met. The M(r) of recSsEF-1 alpha (determined by electrospray MS) was almost coincident with that of the naturally occurring SsEF-1 alpha (SsEF-1 alpha). The thermal-inactivation and thermophilicity profiles of SsEF-1 alpha and recSsEF-1 alpha were identical. Concerning the functional properties, recSsEF-1 alpha was able to support poly(Phe) synthesis in vitro, to bind GDP and GTP and to elicit an NaCl-dependent GTPase activity [Masullo, De Vendittis and Bocchini (1994) J. Biol. Chem. 269, 20376-20379] with the same efficiency as that displayed by SsEF-1 alpha
Rilievi anatomo-istopatologici e caratterizzazione immunoistochimica del medulloblastoma del vitello
No full textGli AA. descrivono i risultati delle indagini anatomo-istopatologiche ed imminuoistochimiche in un caso di neoplasia encefalica con metastasi polmonari osservato in una vitella chianina di 2 mesi di età.
I dati microscopici sono apparsi indicativi per una diagnosi di medulloblastoma; l' applicazione delle tecniche immunoistochimiche ha permesso di accertare la presenza di neurofilamenti (200 Kd) ed assenza di citocheratine, vimentina e Proteina Acida Gliare Fibrillare (GFAP) caratterizzando la differenziazione istogenetica delle cellule neoplastiche verso la linea neuroblastica/neuronale
Organization of a Sulfolobus solfataricus gene cluster homologous to the Escherichia coli str operon
No full textThe Sulfolobus solfataricus S12, S7 and S10 ribosomal proteins and the elongation factor 1 alphagenes are organized in a sequence analogous to that in the Escherichia coli str operon. Northern analysis showed that the S12 gene belongs to a transcript different from that corresponding to the other three genes. Compared to the Sulfolobus acidocaldarius S12 and to the Methanococcus vannielii S7 proteins, the S. solfataricus S12 and S7 proteins were 33 and 47 amino acids longer respectively. These differences were eliminated if the 5' flanking regions of the S. acidocaldarius S12 and the M. vannielii S7 genes were translated from a different start codon. Despite the structural similarities between the archaeal and the bacterial str operons the S. solfataricus ribosomal proteins S12, S7 and S10 are more similar to the eukaryotic counterparts
Nucleotide sequence and molecular evolution of the gene coding for glyceraldehyde-3-phosphate dehydrogenase in the thermoacidophilic archaebacterium Sulfolobus solfataricus
No full textA Sulfolobus solfataricus genomic library cloned in the EMBL3 phage was screened using as probes synthetic oligonucleotides designed from the known amino acid sequence of a peptide obtained from the purified glyceraldehyde-3-phosphate dehydrogenase (aGAPD) protein. The screening led to the isolation of six recombinant phages (λG1–λG6) and one of them (λG4) contained the entire GAPD gene. The deduced amino acid sequence accounts for a protein made of 341 amino acids and the initial methionine is encoded by a GTG triplet. Alignment of the S. solfataricus aGAPD sequence versus GAPD from archaea, eukarya, and bacteria showed that a GAPD is very similar to other archaebacterial but not to eukaryotic or eubacterial GAPD. For known archaebacterial GAPD sequences, the rate of nucleotide substitutions per site per year showed that these sequences are homologous not only at the amino acid but also at the nucleotide level. The evolutionary rates are nearly similar to those reported for other eukaryotic genes
Medulloblastoma in a calf. Anatomo-histopathological, immuno-histochemical and electron-microscopical findings.
No full textIl medulloblastoma è un tumore raro e maligno del vitello normalmente localizzato a livello cerebellare; sono riportati rari casi di metastasi.
Questo lavoro descrive un medulloblastoma nel cervello di una vitella di razza chianina di 2 mesi, affetta da sintomatologia neurologica sin dalla nascita.
E' stata ritrovata nell' emisfero destro connessa con il terzo ventricolo, una massa rotonda, simile ad un mandarino, di dimensioni di 4x3x2.5 cm.
Due metastasi extracraniche sono state osservate nel lobo craniale del polmone destro.
All' esame istologico il neoplasma mostrava una forte cellularità, scarsa componente stromale e poche strutture vasali.
Le cellule tumorali erano allungate con un nucleo denso, scuro ed ovoidale e scarso citoplasma.
Le indagini condotte attraverso l' immunoistochimica con l' uso di anticorpi mono- e poli-clonali unitamente alle osservazioni al microscopio elettronico, hanno contribuito a caratterizzare la natura dello sviluppo neoplastico nel cervello, così come nel polmone
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