Mechanism of peptide modification by low-temperature microwave plasma

Cold atmospheric plasma manipulation of proteins in food systems

“…ROS---for instance superoxide radicals or hydroxyl radicals---seems to be the main contributor to the plasma antibacterial activity (Boudam et al, 2006;Gaunt et al, 2006 (Berlett and Stadtman, 1997). These types of reactions can affect the disulphide bonding state, as previously reported after exposing arginine vasotocin (a peptide model) by microwave plasma (Motrescu et al, 2011). The oxidation of sulphur amino acids is the dominant alteration of proteins during the DBD processing (Lackmann et al, 2015).…”

Effects of non-thermal atmospheric plasma on protein

“…At the quaternary structural level, the effects of NTAP have been demonstrated as induction of aggregations or disruption of assemblies of certain proteins to impair their functions. ( 50 , 67 , 75 , 82 , 83 ) The mechanisms underlying the NTAP-mediated quaternary structural changes involve a complex of modifications of amino acids, electrostatic interactions, and hydrophobic interactions where the manipulation of sulfhydryl group of cysteine residues plays an outstanding role. It is well known that the sulfhydryl group of cysteine is reactive and readily oxidized to form disulfide bond between two different cysteine residues either in the same or different peptide chains.…”

“…In the moderate oxidative environment created by short period of NTAP treatments, free sulfhydryl groups within target protein incline to be oxidized to disulfide and form intra and/or inter-chain cross-links, which leads to the formation of protein aggregates and a reduction in the protein solubility. ( 67 , 75 , 83 ) However, if protein is subjected to a long exposure of NTAP, disulfide would be very likely over-oxidized and transformed to sulfonic and sulfonic acid, resulting in the breakage of disulfide bonds and the disassembly of some protein complexes like antibodies. ( 75 , 82 , 83 ) As well as sulfhydryl group-mediated quaternary structural variations, the carbonylation amino acid side-chain groups introduced by NTAP can generate cross-links between protein molecules and cause aggregation.…”

Tailoring the Surface Functionalities of Radio Frequency Magnetron-Sputtered ZnO Thin Films by Ar/NH3 Gas Mixture Surface-Wave Plasmas

“…For example, recent reports show the possibility to functionalize polymeric materials, 27−30 carbon-based nanomaterials, 31,32 and metals and their oxides 33,34 and even to modify the molecular structure of peptides. 35,36 Up to date, there are not so many reports that investigate the ZnO materials with surface functionalization by plasma processing. 37,38 In this work, we study the effect of different gas mixture ratios of Ar/NH 3 plasma irradiation on the surface properties of the ZnO thin films deposited on the Si substrates by radio frequency (rf) magnetron sputtering.…”

“…Plasma processing of inorganic and organic nanomaterials already proved to be a reliable and reproducible method for improving their functionalities. For example, recent reports show the possibility to functionalize polymeric materials, − carbon-based nanomaterials, , and metals and their oxides , and even to modify the molecular structure of peptides. , Up to date, there are not so many reports that investigate the ZnO materials with surface functionalization by plasma processing. , …”