Characterization of the oligopeptides of Parmigiano-Reggiano cheese soluble in 120 g trichloroacetic acid/1

1994 ◽  
Vol 61 (3) ◽  
pp. 365-374 ◽  
Author(s):  
Francesco Addeo ◽  
Lina Chianese ◽  
Raffaele Sacchi ◽  
Salvatore Spagna Musso ◽  
Pasquale Ferranti ◽  
...  
Keyword(s):  
Fast Atom Bombardment ◽  
Potential Role ◽  
Reversed Phase ◽  
Exchange Chromatography ◽  
Protein Nitrogen ◽  
Main Components ◽  
Hydrolysis Of ◽  
Parmigiano Reggiano

SummaryThe non-protein nitrogen (NPN) of samples of Parmigiano-Reggiano cheese ripened for 6 and 15 months was fractionated by ion-exchange chromatography on a Cu2+-Chelex column to separate oligopeptides from free amino acids. Peptide components were isolated by reversed-phase HPLC and identified by fast atom bombardment–mass spectrometry (FAB–MS). Only the NPN fraction of 6 month old cheese samples contained enough peptides to be further characterized. On the basis of FAB–MS spectral results, 39 oligopeptides were identified, the main components being phosphopeptides. Two sets of both intact and partly dephosphorylated peptides, accounting for a total of 19 phosphopeptides, were formed by the hydrolysis of β–casein and belonged to regions 1–20 and 6–28 of β–casein. The formation and potential role of these peptides in cheese is discussed.

Characterization of Italian populations ofLoliumspp. resistant and susceptible to diclofop by inter simple sequence repeat

Weed Science ◽  
2004 ◽  
Vol 52 (4) ◽  
pp. 554-563 ◽  
Author(s):  
Giovanni Dinelli ◽  
Alessandra Bonetti ◽  
Ilaria Marotti ◽  
Maurizio Minelli ◽  
Pietro Catizone
Keyword(s):  
Potential Role ◽  
Inter Simple Sequence Repeat ◽  
Issr Markers ◽  
Intergeneric Hybridization ◽  
Banding Patterns ◽  
Inter Simple Sequence Repeats ◽  
Range Of Variation ◽  
Simple Sequence

Three ItalianLoliumweed populations, one susceptible and two resistant to diclofop, were characterized by the technique of inter simple sequence repeats (ISSR). The goal of this study was to taxonomically identify theseLoliumpopulations as well as to evaluate evidence for introgression of ISSR fragments fromFestucaand the potential role of this introgression in the diclofop response. ISSR analysis confirmed the genomic background of the weed populations to be consistent with that ofLolium. However, the great range of variation in ISSR banding patterns highlighted that the three ryegrass accessions are mixed populations made up of individuals resulting presumably from intrageneric and intergeneric hybridization in theLolium–Festucacomplex. TwoFestucagenus-discriminating and 20Festucaspecies-discriminating ISSR markers were screened among all the three ryegrass populations. The resistant Tuscania population carried the highest percentage ofFestucagenome (16.8%) followed by the resistant Roma (13.6%) and susceptible Vetralla (7.6%) populations. On the basis of these data some influence ofFestucagenome in diclofop resistance levels of studied ryegrass populations could be hypothesized.

scholarly journals Functional Diversity among Metallo-β-Lactamases: Characterization of the CAR-1 Enzyme of Erwinia carotovora

2008 ◽  
Vol 52 (7) ◽  
pp. 2473-2479 ◽  
Author(s):  
Magdalena Stoczko ◽  
Jean-Marie Frère ◽  
Gian Maria Rossolini ◽  
Jean-Denis Docquier
Keyword(s):  
Functional Diversity ◽  
Clinical Importance ◽  
Erwinia Carotovora ◽  
Exchange Chromatography ◽  
Genome Database ◽  
Reading Frame ◽  
The Family ◽  
Functional Features ◽  
Hydrolysis Of

ABSTRACT Metallo-β-lactamases (MBLs) are zinc-dependent bacterial enzymes characterized by an efficient hydrolysis of carbapenems and a lack of sensitivity to commercially available β-lactamase inactivators. Apart from the acquired subclass B1 enzymes, which exhibit increasing clinical importance and whose evolutionary origin remains unclear, most MBLs are encoded by resident genes found in the genomes of organisms belonging to at least three distinct phyla. Using genome database mining, we identified an open reading frame (ORF) (ECA2849) encoding an MBL-like protein in the sequenced genome of Erwinia carotovora, an important plant pathogen. Although no detectable β-lactamase activity could be found in E. carotovora, a recombinant Escherichia coli strain in which the ECA2849 ORF was cloned showed decreased susceptibility to several β-lactams, while carbapenem MICs were surprisingly poorly affected. The enzyme, named CAR-1, was purified by means of ion-exchange chromatography steps, and its characterization revealed unique structural and functional features. This new MBL was able to efficiently hydrolyze cephalothin, cefuroxime, and cefotaxime and, to a lesser extent, penicillins and the other cephalosporins but only poorly hydrolyzed meropenem, while imipenem was not recognized. CAR-1 is the first example of a functional naturally occurring MBL in the family Enterobacteriaceae (order Enterobacteriales) and highlights the extraordinary structural and functional diversity exhibited by MBLs.

scholarly journals Characterization of indeterminate spleen lesions in primary CT after blunt abdominal trauma: potential role of MR imaging

2014 ◽  
Vol 21 (5) ◽  
pp. 491-498 ◽  
Author(s):  
Sonja Gordic ◽  
Hatem Alkadhi ◽  
Hans-Peter Simmen ◽  
Guido Wanner ◽  
Dieter Cadosch
Keyword(s):  
Mr Imaging ◽  
Abdominal Trauma ◽  
Blunt Abdominal Trauma ◽  
Potential Role

scholarly journals GTPase-Activating Proteins for Cdc42

2002 ◽  
Vol 1 (3) ◽  
pp. 469-480 ◽  
Author(s):  
Gregory R. Smith ◽  
Scott A. Givan ◽  
Paul Cullen ◽  
George F. Sprague
Keyword(s):  
Rho Gtpase ◽  
Invasive Growth ◽  
Gtpase Activating Proteins ◽  
Morphological Defects ◽  
P21 Activated Kinase ◽  
The Individual ◽  
Hydrolysis Of ◽  
Pak Kinase

ABSTRACT The Rho-type GTPase, Cdc42, has been implicated in a variety of functions in the yeast life cycle, including septin organization for cytokinesis, pheromone response, and haploid invasive growth. A group of proteins called GTPase-activating proteins (GAPs) catalyze the hydrolysis of GTP to GDP, thereby inactivating Cdc42. At the time this study began, there was one known GAP, Bem3, and one putative GAP, Rga1, for Cdc42. We identified another putative GAP for Cdc42 and named it Rga2 (Rho GTPase-activating protein 2). We confirmed by genetic and biochemical criteria that Rga1, Rga2, and Bem3 act as GAPs for Cdc42. A detailed characterization of Rga1, Rga2, and Bem3 suggested that they regulate different subsets of Cdc42 function. In particular, deletion of the individual GAPs conferred different phenotypes. For example, deletion of RGA1, but not RGA2 or BEM3, caused hyperinvasive growth. Furthermore, overproduction or loss of Rga1 and Rga2, but not Bem3, affected the two-hybrid interaction of Cdc42 with Ste20, a p21-activated kinase (PAK) kinase required for haploid invasive growth. These results suggest Rga1, and possibly Rga2, facilitate the interaction of Cdc42 with Ste20 to mediate signaling in the haploid invasive growth pathway. Deletion of BEM3 resulted in cells with severe morphological defects not observed in rga1Δ or rga2Δ strains. These data suggest that Bem3 and, to a lesser extent, Rga1 and Rga2 facilitate the role of Cdc42 in septin organization. Thus, it appears that the GAPs play a role in modulating specific aspects of Cdc42 function. Alternatively, the different phenotypes could reflect quantitative rather than qualitative differences in GAP activity in the mutant strains.

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