Nucleotide pirofosfatasi/fosfodiesterasi dal lattice di Euphorbia characias e dai frutti di Opuntia ficus indica: purificazione e caratterizzazione
type: CreativeWork
description: Thesis reports on two metallo-proteins nucleotide pyrophosphatase/phosphodiesterase purified from Euphorbia characias latex (ELNPP) and from prickly pear (Opuntia ficus indica) fruits (ONPP). ELNPP has a molecular mass of 80 kDa and is formed by two apparently identical subunits, each containing 1 Ca2+ and 1 Mg2+ ion. ONPP is a homodimeric protein displaying a molecular mass of 105 kDa. In this enzyme also is present 1 Ca2+ and 1 Mg2+ ion in each subunit. Both ELNPP and ONPP are glycosylated proteins, with an optimum pH of 10.0, are stable at high temperatures and are inhibited by AMP and by EDTA. At the moment we are not able to suggest the exact physiological role of ELNPP and ONPP, however, the high catalytic efficiency of hydrolysis of NAD (P) (H), compared to very low activity of other natural substrates tested, suggesting that these enzymes may modulate the activity of dehydrogenase. In addition, it is observed an increase in the enzymatic activity of ONPP from June to August correlated with the possible modulation of the activity of dehydrogenase, leading us to hypothesize that the ONPP may be one of the factors that influence the ripening of fruits. ------------------------------------------------------------ La tesi di dottorato riporta la purificazione e caratterizzazione di nucleotide pirofosfatasi/fosfodiesterasi dal lattice di Euphorbia characias (ELNPP) e dai frutti di Opuntia ficus indica (ONPP). La ELNPP è una metallo proteina con una massa molecolare di 80 kDa, formata da due identiche subunità ognuna contenente uno ione Ca2+ e uno ione Mg2+. La ONPP è una proteina omodimerica che mostra una massa molecolare di 105 kDa. Anche in questo enzima in ogni subunità è presente uno ione Ca2+ e uno ione Mg2+. Sia la ELNPP che la ONPP sono proteine glicosilate, hanno un optimum di pH a 10.0, sono stabili ad alte temperature e sono inibite dall’EDTA e dall’AMP. Attualmente non siamo in grado di suggerire l’esatto ruolo fisiologico della ELNPP e della ONPP…
abstract: Thesis reports on two metallo-proteins nucleotide pyrophosphatase/phosphodiesterase purified from Euphorbia characias latex (ELNPP) and from prickly pear (Opuntia ficus indica) fruits (ONPP). ELNPP has a molecular mass of 80 kDa and is formed by two apparently identical subunits, each containing 1 Ca2+ and 1 Mg2+ ion. ONPP is a homodimeric protein displaying a molecular mass of 105 kDa. In this enzyme also is present 1 Ca2+ and 1 Mg2+ ion in each subunit. Both ELNPP and ONPP are glycosylated proteins, with an optimum pH of 10.0, are stable at high temperatures and are inhibited by AMP and by EDTA. At the moment we are not able to suggest the exact physiological role of ELNPP and ONPP, however, the high catalytic efficiency of hydrolysis of NAD (P) (H), compared to very low activity of other natural substrates tested, suggesting that these enzymes may modulate the activity of dehydrogenase. In addition, it is observed an increase in the enzymatic activity of ONPP from June to August correlated with the possible modulation of the activity of dehydrogenase, leading us to hypothesize that the ONPP may be one of the factors that influence the ripening of fruits. ------------------------------------------------------------ La tesi di dottorato riporta la purificazione e caratterizzazione di nucleotide pirofosfatasi/fosfodiesterasi dal lattice di Euphorbia characias (ELNPP) e dai frutti di Opuntia ficus indica (ONPP). La ELNPP è una metallo proteina con una massa molecolare di 80 kDa, formata da due identiche subunità ognuna contenente uno ione Ca2+ e uno ione Mg2+. La ONPP è una proteina omodimerica che mostra una massa molecolare di 105 kDa. Anche in questo enzima in ogni subunità è presente uno ione Ca2+ e uno ione Mg2+. Sia la ELNPP che la ONPP sono proteine glicosilate, hanno un optimum di pH a 10.0, sono stabili ad alte temperature e sono inibite dall’EDTA e dall’AMP. Attualmente non siamo in grado di suggerire l’esatto ruolo fisiologico della ELNPP e della ONPP…
author: SPANO', DELIA
language: ita
keywords: Enzimi, Geni codificanti, Metabolismi, Proteine vegetali, Settore BIO/10 - Biochimica
date published: 2011-03-10
date modified: 2026-07-24T01:29:59Z
provider: Università di Cagliari
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Università degli Studi di Cagliari

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property ID: Handle
value: http://hdl.handle.net/11584/266300