scholarly journals Importance of Binding Affinity for the Activity of a Metallodendritic Chemical Nuclease

Pharmaceutics ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 258
Author(s):  
Yi-Hsuan Tang ◽  
Sodio Hsu ◽  
Po-Yu Chen ◽  
Si-ting Liou ◽  
Hui-Ting Chen ◽  
...  
Keyword(s):  
Binding Affinity ◽  
Hydroxyl Radicals ◽  
Gel Electrophoresis ◽  
Nuclease Activity ◽  
Active Species ◽  
Displacement Experiments ◽  
Chemical Nuclease ◽  
Dna Plasmid ◽  
Inhibition Studies ◽  
Cu Complexes

A family of bis(2-pyridyl)amino-modified poly(amidoamine) dendrimer Cu complexes was prepared, and their chemical nuclease activities and binding affinity (Kb) levels for DNA plasmid were investigated. The Kb values of the G2 to G6 apodendrimers for DNA plasmid were found to be 7.4, 23, 48, 70, and 280 µM−1, respectively, using ethidium bromide (EtBr) displacement experiments. The chemical nuclease activities of the corresponding complexes were determined by gel electrophoresis, and a clear positive dendritic effect was observed. Further analysis indicated a linear correlation between the Kb values of the G2 to G5 apodendrimers and the nuclease activity of the corresponding complexes. This observation indicated the importance of substrate binding affinity for macromolecular nuclease activity. In addition, an experiment using 3′-(p-hydroxyphenyl) fluorescein suggested that hydroxyl radicals formed under the tested conditions. Subsequently performed inhibition studies indicated that the hydroxyl radical was the active species responsible for the plasmid cleavage.

Isolation and Characterization of Plasminogen Activator from Pig Leucocytes

1974 ◽  
Vol 31 (01) ◽  
pp. 072-085 ◽  
Author(s):  
M Kopitar ◽  
M Stegnar ◽  
B Accetto ◽  
D Lebez
Keyword(s):  
Molecular Weight ◽  
Plasminogen Activator ◽  
Gel Electrophoresis ◽  
Gel Filtration ◽  
Ph Optimum ◽  
Isolation And Characterization ◽  
Ph Range ◽  
Inhibition Studies ◽  
Final Purification

SummaryPlasminogen activator was isolated from disrupted pig leucocytes by the aid of DEAE chromatography, gel filtration on Sephadex G-100 and final purification on CM cellulose, or by preparative gel electrophoresis.Isolated plasminogen activator corresponds No. 3 band of the starting sample of leucocyte cells (that is composed from 10 gel electrophoretic bands).pH optimum was found to be in pH range 8.0–8.5 and the highest pH stability is between pH range 5.0–8.0.Inhibition studies of isolated plasminogen activator were performed with EACA, AMCHA, PAMBA and Trasylol, using Anson and Astrup method. By Astrup method 100% inhibition was found with EACA and Trasylol and 30% with AMCHA. PAMBA gave 60% inhibition already at concentration 10–3 M/ml. Molecular weight of plasminogen activator was determined by gel filtration on Sephadex G-100. The value obtained from 4 different samples was found to be 28000–30500.

Enhancement of hydroxyl radical generation by phenols and their reaction intermediates during ozonation

1998 ◽  
Vol 38 (6) ◽  
pp. 147-154 ◽  
Author(s):  
Hideo Utsumi ◽  
Sang-Kuk Han ◽  
Kazuhiro Ichikawa
Keyword(s):  
Hydroxyl Radical ◽  
Hydroxyl Radicals ◽  
Spin Trapping ◽  
Active Species ◽  
Generation Rate ◽  
Peak Height Ratio ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Phenol Derivatives ◽  
Semiquinone Radicals

Generation of hydroxyl radicals, one of the major active species in ozonation of water was directly observed with a spin-trapping/electron spin resonance (ESR) technique using 5,5-dimethyl-1-pyrrolineN-oxide (DMPO) as a spin-trapping reagent. Hydroxyl radical were trapped with DMPO as a stable radical, DMPO-OH. Eighty μM of ozone produced 1.08 X 10-6M of DMPO-OH, indicating that 1.4% of •OH is trapped with DMPO. Generation rate of DMPO-OH was determined by ESR/stopped-flow measurement. Phenol derivatives increased the amount and generation rate of DMPO-OH, indicating that phenol derivatives enhance •OH generation during ozonation of water. Ozonation of 2,3-, 2,5-, 2,6-dichlorophenol gave an ESR spectra of triplet lines whose peak height ratio were 1:2:1. ESR parameters of the triplet lines agreed with those of the corresponding dichloro-psemiquinone radical. Ozonation of 2,4,5- and 2,4,6-trichlorophenol gave the same spectra as those of 2,5- and 2,6-dichlorophenol, respectively, indicating that a chlorine group in p-position is substituted with a hydroxy group during ozonation. Amounts of the radical increased in an ozone-concentration dependent manner and were inhibited by addition of hydroxyl radical scavengers. These results suggest that p-semiquinone radicals are generated from the chlorophenols by hydroxyl radicals during ozonation. The p-semiquinone radicals were at least partly responsible for enhancements of DMPO-OH generation.

Synthesis, chemical nuclease activity, and in vitro cytotoxicity of benzimidazole-based Cu(II)/Co(II) complexes

2017 ◽  
Vol 28 (7) ◽  
pp. 1539-1546 ◽  
Author(s):  
Jin-An Zhao ◽  
Huai-Bin Yu ◽  
Shuang-Cheng Zhi ◽  
Rui-Na Mao ◽  
Ji-Yong Hu ◽  
...  
Keyword(s):  
Nuclease Activity ◽  
In Vitro Cytotoxicity ◽  
Chemical Nuclease

scholarly journals Fabrication of La2O3/g-C3N4 Heterojunction with Enhanced Photocatalytic Performance of Tetracycline Hydrochloride

Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1349
Author(s):  
Zhengru Zhu ◽  
Haiwen Xia ◽  
Rina Wu ◽  
Yongqiang Cao ◽  
Hong Li
Keyword(s):  
Hydroxyl Radicals ◽  
Degradation Rate ◽  
Photocatalytic Performance ◽  
Superoxide Radical ◽  
Active Species ◽  
Tetracycline Hydrochloride ◽  
Radical Anions ◽  
Photocatalytic Process ◽  
Composite Photocatalysts ◽  
Ultrasound Assisted

In this study, La2O3/g-C3N4 heterojunction photocatalysts doped with different dosages of La2O3 were constructed by a facile ultrasound-assisted calcination approach. The as-prepared photocatalysts were characterized by XRD, FTIR, FESEM, TEM, XPS, PL and DRS to verify the composite photocatalysts’ purity and to investigate their structural, morphological and elemental composition, and their energy band. According to the results, a type of pure rod–sheet-shaped, heterostructured nanoparticle was successfully obtained. Decorated with 10% La2O3, 2 g/L of the composite sample had a 93% degradation rate for 20 mg/L tetracycline hydrochloride within 2 h under visible light at a pH of 7. After four successive photocatalytic runs, satisfactory stability and reusability was exhibited, with 70% of the tetracycline hydrochloride being removed in the final experiment. Electrons (e−), photogenerated holes (h+), superoxide radical anions (O2−) and hydroxyl radicals (OH) were the fundamental active species during the photocatalytic process and were investigated via quenching experiments. Furthermore, possible photocatalytic mechanisms were analyzed in this work.

MENGEMBANGKAN KEMAMPUAN MAHASISWA PENDIDIKAN BIOLOGI DALAM MENGISOLASI PLASMID BAKTERI SEBAGAI PENGAYAAN PRAKTIKUM MIKROBIOLOGI

2005 ◽  
Vol 6 (2) ◽  
pp. 27
Author(s):  
Mr Kusnadi ◽  
Diana Rochintaniawaty ◽  
Diah Kusumawaty
Keyword(s):  
Gel Electrophoresis ◽  
Standard Procedure ◽  
Biology Education ◽  
Learning Cycle ◽  
Education Students ◽  
Plasmid Isolation ◽  
Class B ◽  
Student’S Performance ◽  
Dna Plasmid ◽  
And Performance

This learning cycle focused on developing of Biology education student’s performance in bacteria DNA-plasmid isolation as well as using gel electrophroresis. The aim of the study was to improve student’s performance in operating equipment used in plasmid isolation such as: micropipettes, microsentrifuge, vortex, shaker-incubator, gel electrophoresis, and UV Trans- illuminator camera. Beside that students were also trained to DNA-plasmid isolation base on standard procedure, so students could identify the form of plasmid via the use of gel electrophoresis. This study was conducted in 2 cycle learning processes as an enrichment of microbiology activity, which associated with molecular microbes genetics. Using observation sheet did evaluation. The study revealed that biology education students had good performance in isolating the plasmid and all group were succeed to isolate the plasmid. Beside that there were increased in knowledge ability especially associated with molecular microbes genetics subject, which achievment gain average was 18,3% (Class A) and 35,4% (class B). The DNA isolation activity in microbiology learning shared high contribution as well as increasing of knowledge achievment and performance ability.Keyword: DNA-plasmid, gel electrophoresis, isolation, learning cycle 

Mineralization of malachite green dye over visible light responsive bismuth doped TiO2–ZrO2 ferromagnetic nanocomposites

2015 ◽  
Vol 39 (5) ◽  
pp. 3629-3638 ◽  
Author(s):  
Archana Charanpahari ◽  
Sachin G. Ghugal ◽  
Suresh S. Umare ◽  
Rajamma Sasikala
Keyword(s):  
Visible Light ◽  
Malachite Green ◽  
Hydroxyl Radicals ◽  
Active Species ◽  
Doped Tio2 ◽  
Malachite Green Dye

Visible light responsive, ferromagnetic, reusable Bi doped TiO2–ZrO2 nanocomposites exhibit enhanced photodegradation and mineralization of malachite green dye. Hydroxyl radicals, holes and superoxides are active species in photodegradation.

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