Cold argon-oxygen plasma species oxidize and disintegrate capsid protein of feline calicivirus

Abstract

Possible mechanisms that lead to inactivation of feline calicivirus (FCV) by cold atmospheric-pressure plasma (CAP) generated in 99% argon-1% O2 admixture were studied. We evaluated the impact of CAP exposure on the FCV viral capsid protein and RNA employing several cultural, molecular, proteomic and morphologic characteristics techniques. In the case of long exposure (2 min) to CAP, the reactive species of CAP strongly oxidized the major domains of the viral capsid protein (VP1) leading to disintegration of a majority of viral capsids. In the case of short exposure (15 s), some of the virus particles retained their capsid structure undamaged but failed to infect the host cells in vitro. In the latter virus particles, CAP exposure led to the oxidation of specific amino acids located in functional peptide residues in the P2 subdomain of the protrusion (P) domain, the dimeric interface region of VP1 dimers, and the movable hinge region linking the S and P domains. These regions of the capsid are known to play an essential role in the attachment and entry of the virus to the host cell. These observations suggest that the oxidative effect of CAP species inactivates the virus by hindering virus attachment and entry into the host cell. Furthermore, we found that the oxidative impact of plasma species led to oxidation and damage of viral RNA once it becomes unpacked due to capsid destruction. The latter effect most likely plays a secondary role in virus inactivation since the intact FCV genome is infectious even after damage to the capsid.

Rapid inactivation of airborne porcine reproductive and respiratory syndrome virus using an atmospheric pressure air plasma

“…For accurate quantification of PRRS virus RNA, PRRSV‐RNA standards/calibration curve was constructed, as described previously with another virus, in which a standard complementary DNA (cDNA) transcript of open reading frame (ORF6) of PRRSV NA genome was used. [ 67 ] This included the targeted sequence of the PCR primers. In RNase‐free water, 10‐fold serial dilution was prepared using viral RNA extracted from 50 µl of PRRS virus with known TCID 50 /ml titer.…”

Comparative evaluation of the virucidal effect of remote and direct cold air plasmas with UV‐C

“…UV‐C affects the virus RNA, while plasma has been shown to oxidize the capsid proteins of the FCV. [ 15,37 ] Oxidation processes have previously been shown to be dependent on humidity or the presence of water on biological substrates, adversely affecting the microbial growth. [ 48 ]…”

“…Feline calicivirus (strain 255) was propagated, concentrated, and titrated in Crandell–Reese feline kidney (CRFK) cells as described previously. [ 15,41 ] Plasma treatments were performed on virus samples at least in triplicate. Averaged results are presented along with the associated standard deviation.…”

“…The strong chemical reactivity induced by cold plasmas at close to room temperature makes it an appropriate candidate for decontamination of heat‐sensitive substrates. There are numerous studies exploring the germicidal activity of cold plasmas against foodborne bacteria, [ 1–11 ] viruses, [ 12–18 ] fungi, [ 19 ] and parasites. [ 20 ] Disinfection using cold plasma can be achieved through interaction of the substrate with either the discharge or the gas treated by the discharge.…”

Foodborne Viruses and Innovative Non-Thermal Food-Processing Technologies

“…Foodborne viruses' inactivation by CP treatment is under intensive research. Extensive research on foodborne viruses and their surrogates have been made in aqueous and liquid media [37,[75][76][77] and also on the surfaces of food [38][39][40]. The majority of the studies have been focused on the susceptibility of HuNoV [78] and its surrogates such as bacteriophage MS2 [79], FCV [80], TV and MNV [38].…”