by Microbiology Doctor dr (doctor_dr)(doctor-dr) plant diversity
VIRUS REPLICATIONVirus particles outside of a host cell have no metabolic activity and are unable to reproduce using the same mechanisms as other microorganisms. The viral protein and nucleic acid components are replicated within the host cells during replication, which is how the virus multiplies. Viruses can multiply in the cytoplasm, nucleus, or both. Much of what we know about viral replication comes from research on E. coli's virulent even-numbered T-phages T2, T4, and T6.
Mechanism of Replication
The mechanism of replication involve the following steps:
i. Adsorption
Ionic bonds or more or fewer particular receptor sites that engage with certain proteins in the capsids or virion allow the virion to adhere to the host cell.
ii. Penetration
Animal viruses are either phagocytosed by the cell or the viral envelope fuses with the host's cell surface membrane, releasing the nucleocapsid into the host cell's cytoplasm. Plant viruses penetrate the cell wall through pores and are subsequently swallowed by the host cell. Plant viruses are usually transferred into the host cell by insects while they are eating.
iii. Component Replication and Biosynthesis
The viral nucleic acid is released from the capsid inside the host cell. Uncoating occurs in the cytoplasm of certain viruses, whereas it happens in the nucleus of others. The nucleic acid gains access to the enzymes and replicates, resulting in viral nucleic acid synthesis and transcription, i.e. the production of mRNA. For the construction of new viruses, mRNA controls the production of proteins in the cytoplasm utilising ribosomes, tRNAs, and enzymes.
iv. Assembly
The components are integrated into mature virus particles when a threshold number of viral components have been produced. in the infected cell's nucleus and/or cytoplasm Except for poxviruses, DNA viruses are formed in the nucleus, whereas RNAviruses are assembled in the cytoplasm.
v. Release
The components are integrated into mature virus particles when a threshold number of viral components have been produced. in the infected cell's nucleus and/or cytoplasm Except for poxviruses, DNA viruses are formed in the nucleus, whereas RNAviruses are assembled in the cytoplasm.
