scholarly journals Partial purification and characterization of a peroxidase activity from human placenta

1990 ◽  
Vol 268 (3) ◽  
pp. 739-743 ◽  
Author(s):  
J L Nelson ◽  
A P Kulkarni
Keyword(s):  
Peroxidase Activity ◽  
Potential Role ◽  
Gel Filtration ◽  
Partial Purification ◽  
Human Haemoglobin ◽  
Prostaglandin Synthase ◽  
Membrane Bound ◽  
Cytochrome P 450

Peroxidases can metabolize a variety of xenobiotics to reactive intermediates capable of binding to protein or DNA. The potential role of these enzymes in fetotoxicity has not been explored. In this study, the presence of peroxidase activity was observed in human term and pre-term placenta. Human term placental peroxidase activity (HTPP) was partially purified by concanavalin A affinity chromatography from CaCl2 extracts of the particulate fraction. HTPP appears to be a membrane-bound glycoprotein. Arachidonic acid-dependent oxidation of guaiacol was not observed, suggesting that the peroxidase activity was not due to prostaglandin synthase. Moreover, HTPP preparations were devoid of catalase and spectrally dissimilar from human haemoglobin, cytochrome P-450, eosinophil peroxidase and myloperoxidase, suggesting an endogenous origin. An Mr of approx. 119,000 was determined for HTPP by gel filtration. Cathodic slab-PAGE of cetyltrialkylammonium bromide-solubilized HTPP yielded two peroxidase-staining bands.

scholarly journals Partial purification and characterization of an endo-α-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242

1992 ◽  
Vol 288 (2) ◽  
pp. 475-482 ◽  
Author(s):  
I Ishii-Karakasa ◽  
H Iwase ◽  
K Hotta ◽  
Y Tanaka ◽  
S Omura
Keyword(s):  
Enzyme Activity ◽  
Culture Medium ◽  
Gel Filtration ◽  
Partial Purification ◽  
Gastric Mucus ◽  
Purification And Characterization ◽  
Streptomyces Sp ◽  
Optimum Ph ◽  
New Type

For the purification of a new type of endo-alpha-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242 (endo-GalNAc-ase-S) [Iwase, Ishii, Ishihara, Tanaka, Omura & Hotta (1988) Biochem. Biophys. Res. Commun. 151, 422-428], a method for assaying enzyme activity was established. Using purified pig gastric mucus glycoprotein (PGM) as the substrate, oligosaccharides liberated from PGM were pyridylaminated, and the reducing terminal sugars of oligosaccharides larger than Gal beta 1-3GalNAc were analysed by h.p.1.c. The crude enzyme of endo-GalNAc-ase-S was prepared as an 80% (w/v) ammonium sulphate precipitate from the concentrated culture medium. The enzyme was partially purified by gel chromatofocusing and subsequent DEAE-Toyopearl chromatography. Endo-enzyme activity eluted around pI 4.8 on a gel chromatofocusing column and eluted with 0.19-0.25 M-NaCl on a DEAE-Toyopearl column. In the enzyme fraction obtained, no exo-glycosidases or proteases could be detected. The molecular mass of the enzyme was estimated as 105 kDa by gel filtration, and the optimum pH was 5.5. Endo-GalNAc-ase-S hydrolysed the O-glycosidic linkage between GalNAc and Ser (Thr) in 3H-labelled and unlabelled asialofetuin, liberating both the disaccharide (Gal beta 1-3GalNAc) and the tetrasaccharide [Gal beta 1-3 (Gal beta 1-4GlcNAc beta 1-6)GalNAc]. When endo-alpha-N-acetylgalactosaminidase from Alcaligenes sp. (endo-GalNac-ase-A) was incubated with 3H-labelled and unlabelled asialofetuin, only the disaccharide (Gal beta 1-3GalNAc) was liberated.

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 Is There a Link between Bisphenol A (BPA), a Key Endocrine Disruptor, and the Risk for SARS-CoV-2 Infection and Severe COVID-19?

2020 ◽  
Vol 9 (10) ◽  
pp. 3296
Author(s):  
Aeman Zahra ◽  
Cristina Sisu ◽  
Elisabete Silva ◽  
Sophie-Christine De Aguiar Greca ◽  
Harpal S. Randeva ◽  
...  
Keyword(s):  
Bisphenol A ◽  
Potential Role ◽  
Metabolic Diseases ◽  
Endocrine Disrupting Chemicals ◽  
Angiotensin Converting Enzyme 2 ◽  
Endocrine Disrupting ◽  
Membrane Bound ◽  
Transmembrane Serine Protease ◽  
G Protein Coupled

Infection by the severe acute respiratory syndrome (SARS) coronavirus-2 (SARS-CoV-2) is the causative agent of a new disease (COVID-19). The risk of severe COVID-19 is increased by certain underlying comorbidities, including asthma, cancer, cardiovascular disease, hypertension, diabetes, and obesity. Notably, exposure to hormonally active chemicals called endocrine-disrupting chemicals (EDCs) can promote such cardio-metabolic diseases, endocrine-related cancers, and immune system dysregulation and thus, may also be linked to higher risk of severe COVID-19. Bisphenol A (BPA) is among the most common EDCs and exerts its effects via receptors which are widely distributed in human tissues, including nuclear oestrogen receptors (ERα and ERβ), membrane-bound oestrogen receptor (G protein-coupled receptor 30; GPR30), and human nuclear receptor oestrogen-related receptor gamma. As such, this paper focuses on the potential role of BPA in promoting comorbidities associated with severe COVID-19, as well as on potential BPA-induced effects on key SARS-CoV-2 infection mediators, such as angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2). Interestingly, GPR30 appears to exhibit greater co-localisation with TMPRSS2 in key tissues like lung and prostate, suggesting that BPA exposure may impact on the local expression of these SARS-CoV-2 infection mediators. Overall, the potential role of BPA on the risk and severity of COVID-19 merits further investigation.

scholarly journals Optimization of Growth Conditions for Purification and Production of L-Asparaginase bySpirulina maxima

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Hanaa H. Abd El Baky ◽  
Gamal S. El Baroty
Keyword(s):  
Enzyme Activity ◽  
Gel Filtration ◽  
Growth Conditions ◽  
Partial Purification ◽  
Specific Enzyme ◽  
Purification And Characterization ◽  
Spirulina Maxima ◽  
Optimum Ph ◽  
Biomass Yields

L-asparaginase (L-AsnA) is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA fromSpirulina maxima(SM) were tested. SM cultures grown in Zarrouk medium containing different N2(in NaNO3form) concentrations (1.25, 2.50, and 5.0 g/L) for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2) showed a high AsnA enzyme activity (898 IU), total protein (405 mg/g), specific enzyme activity (2.21 IU/mg protein), and enzyme yield (51.28 IU/L) compared with those in low N2cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production inS. maxima.

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

Characterization and partial purification of a broad spectrum antibiotic AS-48 produced by Streptococcus faecalis

1986 ◽  
Vol 32 (10) ◽  
pp. 765-771 ◽  
Author(s):  
A. Gálvez ◽  
M. Maqueda ◽  
E. Valdivia ◽  
A. Quesada ◽  
E. Montoya
Keyword(s):  
Broad Spectrum ◽  
Gel Filtration ◽  
Basal Medium ◽  
Exchange Chromatography ◽  
Partial Purification ◽  
Gram Negative Bacteria ◽  
Broad Spectrum Antibiotic ◽  
Streptococcus Faecalis ◽  
Group D

Streptococcus faecalis S-48 produces a broad spectrum antibiotic, active against Gram-positive and Gram-negative bacteria. This substance is produced in solid and liquid media and also in a defined basal medium. It is sensitive to protease, pronase, or trypsin, heating at 70 °C, and alkaline pH, but resistant to treatment with lipase, lysozyme, alkaline phosphatase, DNAase, RNAase, acidic or neutral pHs, and also lower temperatures (60 °C). Several organic solvents cause precipitation, but not inactivation. This antibiotic has been partially purified by gel filtration and further ion-exchange chromatography. Its molecular weight has been estimated close to 2000. The biological activity of this antagonistic substance against the selected indicator strains, Streptococcus faecalis S-47 and Escherichia coli U-9, is bactericidal. The characterization of this substance, initially classified as a bacteriocin, indicates that it is an antibiotic of peptidic nature. The significance of antibiotic occurrence in group D of the genus Streptococcus is also discussed.

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