scholarly journals Reactive species driven oxidative modifications of peptides—Tracing physical plasma liquid chemistry

2021 ◽  
Vol 129 (19) ◽  
pp. 193305
Author(s):  
Sebastian Wenske ◽  
Jan-Wilm Lackmann ◽  
Larissa Milena Busch ◽  
Sander Bekeschus ◽  
Thomas von Woedtke ◽  
...  
2021 ◽  
Vol 326 ◽  
pp. 129007
Author(s):  
Zahra Nasri ◽  
Giuliana Bruno ◽  
Sander Bekeschus ◽  
Klaus-Dieter Weltmann ◽  
Thomas von Woedtke ◽  
...  

2004 ◽  
Vol 286 (6) ◽  
pp. F1202-F1208 ◽  
Author(s):  
Lan Chen ◽  
Catherine M. Fuller ◽  
Thomas R. Kleyman ◽  
Sadis Matalon

We studied the effects of two mutations of the extracellular loop of the α-subunit of the (ENaC) on amiloride-sensitive current in Xenopus laevis oocytes and the inhibition of this current by 3-morpholinosydnonimine (SIN-1). Injection of oocytes with wild-type (wt) α-,β-,γ-rENaC cRNA (8.3 ng/subunit) resulted 48–72 h later in inward Na+ currents (−5.5 ± 0.8 μA; means ± SE at −100 mV; n = 21), which were completely inhibited by amiloride. Oocytes injected with either αY279A- or αY283A- and β-,γ-rENaC cRNAs had significantly lower Na+ currents. Furthermore, αY279A-,β-,γ-rENaC-injected oocytes had a higher Ki for amiloride (0.54 ± 0.97 vs. 0.10 ± 0.04 μM; P < 0.01). Exposure of oocytes to SIN-1 (1 mM) for 5 min decreased both total Na+ and amiloride-sensitive currents across wt and αY279A- but not αY283A-,β-,γ-rENaC. Furthermore, exposure to SIN-1 increased the Ki for amiloride across wt but not αY279A-,β-,γ-rENaC-injected oocytes. These data indicate that both tyrosines are important for proper ENaC function and their oxidative modifications contribute to altered ENaC function.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
M. Ravandeh ◽  
H. Kahlert ◽  
H. Jablonowski ◽  
J.-W. Lackmann ◽  
J. Striesow ◽  
...  

Abstract Reactive oxygen and nitrogen species (RONS), e.g. generated by cold physical plasma (CPP) or photodynamic therapy, interfere with redox signaling pathways of mammalian cells, inducing downstream consequences spanning from migratory impairment to apoptotic cell death. However, the more austere impact of RONS on cancer cells remains yet to be clarified. In the present study, a combination of electrochemistry and high-resolution mass spectrometry was developed to investigate the resilience of solid-supported lipid bilayers towards plasma-derived reactive species in dependence of their composition. A 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid bilayer was undisturbed by 200 µM H2O2 (control) but showed full permeability after CPP treatment and space-occupying oxidation products such as PoxnoPC, PAzePC, and POPC hydroperoxide were found. Electron paramagnetic resonance spectroscopy demonstrated the presence of hydroxyl radicals and superoxide anion/hydroperoxyl radicals during the treatment. In contrast, small amounts of the intramembrane antioxidant coenzyme Q10 protected the bilayer to 50% and LysoPC was the only POPC derivative found, confirming the membrane protective effect of Q10. Such, the lipid membrane composition including the presence of antioxidants determines the impact of pro-oxidant signals. Given the differences in membrane composition of cancer and healthy cells, this supports the application of cold physical plasma for cancer treatment. In addition, the developed model using the combination of electrochemistry and mass spectrometry could be a promising method to study the effect of reactive species or mixes thereof generated by chemical or physical sources.


2018 ◽  
Vol 400 (1) ◽  
pp. 19-38 ◽  
Author(s):  
Kristian Wende ◽  
Thomas von Woedtke ◽  
Klaus-Dieter Weltmann ◽  
Sander Bekeschus

AbstractReactive oxygen and nitrogen species deposited by cold physical plasma are proposed as predominant effectors in the interaction between discharge and biomedical application. Most reactive species found in plasma sources are known in biology for inter- and intracellular communication (redox signaling) and mammalian cells are equipped to interpret the plasma derived redox signal. As such, considerable effort has been put into the investigation of potential clinical applications and the underlying mechanism, with a special emphasis on conditions orchestrated significantly via redox signaling. Among these, immune system control in wound healing and cancer control stands out with promisingin vitroandin vivoeffects. From the fundamental point of view, further insight in the interaction of the plasma-derived species with biological systems is desired to (a) optimize treatment conditions, (b) identify new fields of application, (c) to improve plasma source design, and (d) to identify the trajectories of reactive species. Knowledge on the biochemical reactivity of non-thermal plasmas is compiled and discussed. While there is considerable knowledge on proteins, lipids and carbohydrates have not received the attention deserved. Nucleic acids have been profoundly investigated yet focusing on molecule functionality rather than chemistry. The data collected underline the efforts taken to understand the fundamentals of plasma medicine but also indicate ‘no man’s lands’ waiting to be discovered.


1991 ◽  
Vol 223 ◽  
Author(s):  
Hans P. Zappe ◽  
Gudrun Kaufel

ABSTRACTThe effect of numerous plasma reative ion etch and physical milling processes on the electrical behavior of GaAs bulk substrates has been investigated by means of electric microwave absorption. It was seen that plasma treatments at quite low energies may significantly affect the electrical quality of the etched semiconductor. Predominantly physical plasma etchants (Ar) were seen to create significant damage at very low energies. Chemical processes (involving Cl or F), while somewhat less pernicious, also gave rise to electrical substrate damage, the effect greater for hydrogenic ambients. Whereas rapid thermal anneal treatments tend to worsen the electrical integrity, some substrates respond positively to long-time high temperature anneal steps.


Author(s):  
Hassan Tahir ◽  
Umair Khan ◽  
Anwarud Din ◽  
Yu-Ming Chu ◽  
Noor Muhammad

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 999 ◽  
Author(s):  
Aranza Denisse Vital-Grappin ◽  
Maria Camila Ariza-Tarazona ◽  
Valeria Montserrat Luna-Hernández ◽  
Juan Francisco Villarreal-Chiu ◽  
Juan Manuel Hernández-López ◽  
...  

Microplastics (MPs) are distributed in a wide range of aquatic and terrestrial ecosystems throughout the planet. They are known to adsorb hazardous substances and can transfer them across the trophic web. To eliminate MPs pollution in an environmentally friendly process, we propose using a photocatalytic process that can easily be implemented in wastewater treatment plants (WWTPs). As photocatalysis involves the formation of reactive species such as holes (h+), electrons (e−), hydroxyl (OH●), and superoxide ion (O2●−) radicals, it is imperative to determine the role of those species in the degradation process to design an effective photocatalytic system. However, for MPs, this information is limited in the literature. Therefore, we present such reactive species’ role in the degradation of high-density polyethylene (HDPE) MPs using C,N-TiO2. Tert-butanol, isopropyl alcohol (IPA), Tiron, and Cu(NO3)2 were confirmed as adequate OH●, h+, O2●− and e− scavengers. These results revealed for the first time that the formation of free OH● through the pathways involving the photogenerated e− plays an essential role in the MPs’ degradation. Furthermore, the degradation behaviors observed when h+ and O2●− were removed from the reaction system suggest that these species can also perform the initiating step of degradation.


2021 ◽  
Vol 165 ◽  
pp. 54
Author(s):  
Patricia de la Cruz-Ojeda ◽  
M. Ángeles Rodríguez-Hernández ◽  
Elena Navarro-Villarán ◽  
Paloma Gallego ◽  
Pavla Staňková ◽  
...  

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