Infection in other species Virus

1 infection in other species

1.1 animal viruses
1.2 plant viruses
1.3 bacterial viruses
1.4 archaeal viruses

infection in other species

viruses infect cellular life and, although viruses occur universally, each cellular species has own specific range infect species. viruses, called satellites, can replicate within cells have been infected virus.

animal viruses

viruses important pathogens of livestock. diseases such foot-and-mouth disease , bluetongue caused viruses. companion animals such cats, dogs, , horses, if not vaccinated, susceptible serious viral infections. canine parvovirus caused small dna virus , infections fatal in pups. invertebrates, honey bee susceptible many viral infections. however, viruses co-exist harmlessly in host , cause no signs or symptoms of disease.

plant viruses

peppers infected mild mottle virus

there many types of plant virus, cause loss of yield, , not economically viable try control them. plant viruses spread plant plant organisms, known vectors. these insects, fungi, nematode worms, , single-celled organisms have been shown vectors. when control of plant virus infections considered economical, perennial fruits, example, efforts concentrated on killing vectors , removing alternate hosts such weeds. plant viruses cannot infect humans , other animals because can reproduce in living plant cells.

plants have elaborate , effective defence mechanisms against viruses. 1 of effective presence of so-called resistance (r) genes. each r gene confers resistance particular virus triggering localised areas of cell death around infected cell, can seen unaided eye large spots. stops infection spreading. rna interference effective defence in plants. when infected, plants produce natural disinfectants kill viruses, such salicylic acid, nitric oxide, , reactive oxygen molecules.

plant virus particles or virus-like particles (vlps) have applications in both biotechnology , nanotechnology. capsids of plant viruses simple , robust structures , can produced in large quantities either infection of plants or expression in variety of heterologous systems. plant virus particles can modified genetically , chemically encapsulate foreign material , can incorporated supramolecular structures use in biotechnology.

bacterial viruses

transmission electron micrograph of multiple bacteriophages attached bacterial cell wall

bacteriophages common , diverse group of viruses , abundant form of biological entity in aquatic environments – there ten times more of these viruses in oceans there bacteria, reaching levels of 250,000,000 bacteriophages per millilitre of seawater. these viruses infect specific bacteria binding surface receptor molecules , entering cell. within short amount of time, in cases minutes, bacterial polymerase starts translating viral mrna protein. these proteins go on become either new virions within cell, helper proteins, assembly of new virions, or proteins involved in cell lysis. viral enzymes aid in breakdown of cell membrane, and, in case of t4 phage, in on twenty minutes after injection on 3 hundred phages released.

the major way bacteria defend bacteriophages producing enzymes destroy foreign dna. these enzymes, called restriction endonucleases, cut viral dna bacteriophages inject bacterial cells. bacteria contain system uses crispr sequences retain fragments of genomes of viruses bacteria have come contact in past, allows them block virus s replication through form of rna interference. genetic system provides bacteria acquired immunity infection.

archaeal viruses

some viruses replicate within archaea: these double-stranded dna viruses unusual , unique shapes. these viruses have been studied in detail in thermophilic archaea, particularly orders sulfolobales , thermoproteales. defences against these viruses involve rna interference repetitive dna sequences within archaean genomes related genes of viruses. archaea have crispr–cas systems adaptive defence against viruses. these enable archaea retain sections of viral dna, used target , eliminate subsequent infections virus using process similar rna interference.