1,204 research outputs found
A NAD(P)H oxidase isolated from the archaeon Sulfolobus solfataricus is not homologous with another NADH oxidase present in the same microorganism
No full textA NAD(P)H oxidase has been isolated from the ar- chaeon Sulfolobus solfataricus. The enzyme is a ho- modimer with Mr 38,000 per subunit (SsNOX38) contain- ing 1 FAD molecule/subunit. It oxidizes NADH and, less efficiently, NADPH with the formation of hydrogen per- oxide. The enzyme was resistant against chemical and physical denaturating agents. The temperature for its half-denaturation was 93 and 75 °C in the absence or presence, respectively, of 8 M urea. The enzyme did not show any reductase activity. The SsNOX38 encoding gene was cloned and sequenced. It accounted for a prod- uct of 36.5 kDa. The translated amino acid sequence was made of 332 residues containing two putative -fold regions, typical of NAD- and FAD-binding proteins. The primary structure of SsNOX38 did not show any homol- ogy with the N-terminal amino acid sequence of a NADH oxidase previously isolated from S. solfataricus (Ss- NOX35) (Masullo, M., Raimo, G., Dello Russo, A., Boc- chini, V. and Bannister, J. V. (1996) Biotechnol. Appl. Biochem. 23, 47–54). Conversely, it showed 40% sequence identity with a putative thioredoxin reductase from Ba- cillus subtilis, but it did not contain cysteines, which are essential for the activity of the reductase
Valine 114 Replacements in Archaeal Elongation Factor 1A Enhanced Its Ability To Interact with Aminoacyl-tRNA and Kirromycin
No full textValine 114 in the D109AAILVVA sequence of elongation factor 1R from the archaeon Sulfolobus solfataricus (SsEF-1R) was substituted with an acidic (V114E), basic (V114K), or cavity-forming (V114A) residue, and the effects on the biochemical properties of the factor were investigated. This sequence is well-conserved among most of eukaryal and eubacterial counterparts, and in the three-dimensional structure of SsEF-1R, V114 is located in a hydrophobic pocket near the first GDP-binding consensus sequence G13XXXXGK[T,S] [Vitagliano, L., Masullo, M., Sica, F., Zagari, A., and Bocchini, V. (2001) EMBO J. 20, 5305-5311]. These mutants displayed functions absent in the wild-type factor. In fact, although they exhibited a rate in poly(Phe) incorporation almost identical to that of SsEF-1R, V114K and V114A exhibited an affinity for GDP and GTP higher and a capability to bind heterologous aa-tRNA stronger than that elicited by SsEF-1R but similar to that of eubacterial EF-Tu. V114E instead displayed not only a weaker binding capability for aa-tRNA but also a lower affinity for GDP. The intrinsic GTPase activity of V114E was drastically reduced compared to those of SsEF-1R, V114K, and V114A. Interestingly, the decreased intrinsic GTPase activity of V114E was partially restored by kirromycin, an effect already observed for the G13A mutant of SsEF-1R [Masullo, M., Cantiello, P., de Paola, B., Catanzano, F., Arcari, P., and Bocchini, V. (2002) Biochemistry 41, 628-633]. Finally, the V114A substitution showed only a marginal effect on both the thermostability and thermophilicity of SsEF-1R, whereas V114K and V114E replacements strongly destabilized the molecule
Oltre il rinvio quoad poenam: un’interpretazione che ricompone le disarmonie di tutela tra coniuge separato e coniuge divorziato?
No full textLe Sezioni Unite, nella sentenza in commento, hanno stabilito che il rinvio quoad poenam all’art. 570 c.p. contenuto all’art. 12 sexies della l. n. 898 del 1970 si riferisce al primo comma della disposizione codicistica e, dunque, alle pene alternative della reclusione e della multa. La decisione ribalta il più recente e consoli- dato orientamento della giurisprudenza di legittimità che - sulla base di una presunta affinità strutturale del modello di incriminazione dell’art. 12 sexies con l’omessa prestazione dei mezzi di sussistenza di cui all’art. 570, comma 2, c.p. - aveva invece interpretato il rinvio come riferito a quest’ultima disposizione e conse- guentemente alla pena congiunta della reclusione e della multa. La pronuncia è di notevole interesse non soltanto per l’originalità della soluzione accolta, ma soprattutto per i riflessi applicativi che è destinata a ri- verberare in ordine all’interpretazione della fattispecie “richiamata” di violazione degli obblighi di assistenza di cui al primo comma dell’art. 570 c.p., destinata ad ampliare il suo raggio di azione, secondo la lettura of- ferta dalle Sezioni Unite, anche all’omessa corresponsione dell’assegno di mantenimento al coniuge sepa- rato, fino ad oggi relegata nelle maglie repressive dell’ipotesi di cui al secondo comma, laddove tale ina- dempimento si fosse tradotto nel far mancare i mezzi di sussistenza
Scrivere la guerra. Corso avanzato di Lingua e cultura araba per lauree specialistiche (units 1-6, 9-10, 20; 19.3, 19.4, 19.5)
No full textIl volume mette a disposizione degli studenti di lauree magistrali i risultati delle ricerche degli autori su questioni letterarie, sociali e politiche relative al mondo arabo contemporane
Mayy Ziyada (1883-1941) tra femminismo e nazionalismo
No full textthe arab Nahḍa, a cultural Renaissance that spanned the period from
late 19th to early 20th century, witnessed the spring of new issues and tendencies.
in egypt, women intellectuals claimed more space in the public
debate, while supporting the nationalist movements which ultimately led to
the independence of the country. among them, the eclectic author Mayy
Ziyāda (1883-1941) played a pivotal role in the elaboration of nationalistic
and gender-related issues. this study investigates Ziyāda’s writings about
women’s condition, showing how she was actually more focused on the liberal
political discourse rather than feminist theories and practices. it also
aims at demostrating how Ziyāda, who was crucial in defining a canon of
women’s culture of her time, did not embrace it completel
In tema di condivisione dei luoghi di detenzione della sostanza stupefacente e partecipazione nell'altrui reato
No full textExpression in Escherichia coli of thermostable elongation factor I 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
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