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Non-Photocatalytic and Photocatalytic Inactivation of Viruses Using Antiviral Assays and Antiviral Nanomaterials
Published in Devarajan Thangadurai, Saher Islam, Charles Oluwaseun Adetunji, Viral and Antiviral Nanomaterials, 2022
Suman Tahir, Noor Tahir, Tajamal Hussain, Zubera Naseem, Muhammad Zahid, Ghulam Mustafa
For self-reproduction, viruses use their host cells. Viral contagion mainly includes six stages: attachment, entrance, uncoating, repetition, assembly, and release (Oswald et al. 2017). Through binding proteins in capsid surrounded in the enveloped virus, viruses bind to particular receptor positions on the cell membrane of the host. This connection specificity establishes host cells that may be affected through a specific viral type. The capsid remains exterior to the cell; only bacteriophage nucleic acid enters into the host cells. Viruses of animals and certain florae can penetrate the cell by endocytosis, i.e. the whole virus being enclosed and engulfed through the cell membrane. Once the virus envelope combines with cell membrane, enveloped viruses will penetrate into the host. Within the host cell, when virus capsid is damaged, a discharge of virus nucleic acid results, which afterward can be used for transcription and multiplication. Mechanism of repetition is dependent on the genome of virus. Generally, DNA viruses consume proteins and enzymes of host cells to generate extra DNA, which is transcribed to messenger RNA (mRNA), and later utilised for the formation of protein. Typically, RNA viruses consume core of RNA for the production of mRNA, along with virus genomic RNA. The last step of viral multiplication is a discharge of new virions made in the host cells, permitting contagion of neighboring cells and duplication of self-multiplication cycles. In host cells, virus repetition cycle can make severe biochemical and structural variations and cause harm to them (Yang et al. 2017).
Animal Connection Challenges
Published in Michael Hehenberger, Zhi Xia, Huanming Yang, Our Animal Connection, 2020
Michael Hehenberger, Zhi Xia, Huanming Yang
An important concept for viral classification is the “viral envelope.” Many viruses have envelopes covering their protective protein capsid, i.e., the protein shell of a virus, enclosing the genetic material of the virus. The envelopes typically are derived from portions of the host cell membranes (phospholipids and proteins), but may include some viral glycoproteins.b Viral envelopes are essential for providing the entry into host cells. They may even help viruses to avoid the host immune system. Glycoproteins on the surface of the envelope serve to identify and bind to receptor sites on the host’s membrane. The viral envelope then fuses with the host’s membrane, allowing the capsid and viral genome to enter and infect the host. Figure 8.2 shows the viral envelope for the Cytomegalovirus, a member of the viral family known as Herpesviridae or herpesviruses. Herpesviruses like CMV (frequently associated with the salivary glands) share a characteristic ability to remain latent within the body over long periods.
Dielectrophoresis of complex bioparticles
Published in Michael Pycraft Hughes, Nanoelectromechanics in Engineering and Biology, 2018
In addition to the payload and the capsid, many viruses have an extra lipid membrane (or envelope) similar to that which encloses cells. These are referred to as enveloped viruses, whereas those without membranes have naked capsids. In the vast majority of cases, there is also a layer of protein gel between the capsid and envelope called the tegument. Most such viruses also have glycoprotein molecules protruding from the envelope; these are molecules that interact with the surface of the host cell and aid in the infection process. Again, a number of common human viruses share this structure; examples include various herpes viruses (including those responsible for cold sores and chicken pox), and orthomyxovirus (which causes influenza). The capsid structure in enveloped viruses may either be icosahedral or helical; in the latter case the helix may be wrapped into a ball, such as in the case of influenza.
Critical Review and Research Needs of Ozone Applications Related to Virus Inactivation: Potential Implications for SARS-CoV-2
Published in Ozone: Science & Engineering, 2021
Christina Morrison, Ariel Atkinson, Arash Zamyadi, Faith Kibuye, Michael McKie, Samantha Hogard, Phil Mollica, Saad Jasim, Eric C. Wert
Ozone has received increased attention for use against viruses due to its strong disinfection abilities. In general, viruses consist of a nucleic acid genome (DNA or RNA) coated by a protein comprised nucleocapsid. Some viruses, such as SARS-CoV-2, additionally maintain a viral envelope comprised lipids and proteins from its host cell membrane as its outermost layer. Enveloped viruses have long been assumed to exhibit decreased environmental persistence when compared to non-enveloped viruses, which has resulted in their omission in many environmental-related disinfection studies (Wigginton, Ye, and Ellenberg 2015).