pathogenicity island

Examples of pathogenicity island in the following topics:

• Pathogenicity Islands and Virulence Factors

  • Pathogenicity islands (PAIs) are a distinct class of genomic islands acquired by microorganisms through horizontal gene transfer.
  • Pathogenicity islands (PAIs) are a distinct class of genomic islands acquired by microorganisms through horizontal gene transfer.
  • These mobile genetic elements may range from 10-200 kb, and may encode genes contributing to the virulence of the respective pathogen.
  • Pathogenicity islands are discrete genetic units flanked by direct repeats, insertion sequences or tRNA genes, which act as sites for recombination into the DNA.
  • The GC-content of pathogenicity islands often differs from that of the rest of the genome, potentially aiding in their detection within a given DNA sequence.

• Pathogenicity Islands

  • Pathogenicity islands (PAIs) are a distinct class of genomic islands acquired by microorganisms through horizontal gene transfer.
  • Pathogenicity islands are discrete genetic units flanked by direct repeats, insertion sequences or tRNA genes, which act as sites for recombination into the DNA.
  • Pathogenicity islands carry genes encoding one or more virulence factors, including, but not limited to, adhesins, toxins, or invasins.
  • The GC-content of pathogenicity islands often differs from that of the rest of the genome, potentially aiding in their detection within a given DNA sequence.
  • Pathogenicity islands are transferred horizontally, this details some of the ways that occurs.

• Extent of Host Involvement

  • Host-pathogen interactions are the interactions taking place between a pathogen (e.g. virus, bacteria) and their host (e.g. humans, plants).
  • Host-pathogen interactions are the interactions that take place between a pathogen (e.g. virus, bacteria) and their host (e.g. humans, plants).
  • By definition, all pathogens damage their host to some extent.
  • The appearance and severity of disease resulting from the presence of any pathogen depends upon the ability of that pathogen to damage the host as well as the ability of the host to resist the pathogen.
  • Clinicians therefore classify infectious microorganisms or microbes according to the status of host defenses - either as primary pathogens or as opportunistic pathogens.

• Toll-Like Receptors

  • TLRs are a type of pattern recognition receptor (PRR) and recognize molecules that are broadly shared by pathogens but distinguishable from host molecules, collectively referred to as pathogen-associated molecular patterns (PAMPs).
  • Because of the specificity of Toll-like receptors (and other innate immune receptors) they cannot easily be changed in the course of evolution, these receptors recognize molecules that are constantly associated with threats (i.e., pathogen or cell stress) and are highly specific to these threats (i.e., cannot be mistaken for self molecules).
  • Pathogen-associated molecules that meet this requirement are usually critical to the pathogen's function and cannot be eliminated or changed through mutation; they are said to be evolutionarily conserved.
  • Well-conserved features in pathogens include bacterial cell-surface lipopolysaccharides (LPS), lipoproteins, lipopeptides, and lipoarabinomannan; proteins such as flagellin from bacterial flagella; double-stranded RNA of viruses; or the unmethylated CpG islands of bacterial and viral DNA; and certain other RNA and DNA.

• Rickettsial Diseases

  • Human immune response to the scrub typhus pathogen, Orientia tsutsugamushi, appears to provide a beneficial effect against HIV infection progress, negatively influencing the virus replication process.
  • A probable reason for this actively studied phenomenon is a certain degree of homology between the rickettsia and the virus – namely, common epitope(s) due to common genome fragment(s) in both pathogens.
  • Rickettsia species are carried by many ticks, fleas, and lice, and cause diseases in humans such as typhus, rickettsialpox, Boutonneuse fever, African tick bite fever, Rocky Mountain spotted fever , Flinders Island spotted fever, and Queensland tick typhus (Australian Tick Typhus).
  • All three of these groups contain human pathogens.

• Intracellular Pathogens

  • Not all pathogens are undesirable to humans.
  • In entomology, pathogens are one of the "Three P's" (predators, pathogens, and parasitoids) that serve as natural or introduced biological controls to suppress arthropod pest populations.
  • There are several types of intracellular pathogens.
  • Bacteria can often be killed by antibiotics because the cell wall in the outside is destroyed, expelling the DNA out of the body of the pathogen, therefore making the pathogen incapable of producing proteins, so it dies.
  • According to the prion theory, prions are infectious pathogens that do not contain nucleic acids.

• Regulating Virulence

  • There are three main hypotheses about why a pathogen evolves as it does.
  • For example, if the host dies, the pathogen population inside may die out entirely.
  • Pathogen strains that kill the host can increase in frequency as long as the pathogen can transmit itself to a new host, whether before or after the host dies.
  • The evolution of virulence in pathogens is a balance between the costs and benefits of virulence to the pathogen.
  • These traits typically arise due to mutations, which occur more frequently in pathogen populations than in host populations, due to the pathogens' rapid generation time and immense numbers.

• Airborne Transmission of Disease

  • Airborne diseases are characterized by diseases that are transmitted through the air via the presence of a pathogen.
  • Airborne diseases are characterized by diseases that are transmitted through the air via the presence of a pathogen.
  • These pathogens can include both viruses and bacteria that are spread by coughing, sneezing, laughing, or through personal contact.
  • The airborne transmission that occurs utilizes small particles or droplet nucleithat contains these infectious agents or pathogens.
  • Often times, these airborne pathogens can result in inflammation in the nose, throat, sinuses, and the lungs.

• West Nile Virus

  • The virus has now spread across the continental United States, north into Canada, and southward into the Caribbean Islands and Latin America.
  • WNV is now considered to be an endemic pathogen in Africa, Asia, Australia, the Middle East, Europe and in the United States.

• Emerging and Reemerging Infectious Diseases

  • Emerging infections account for at least 12% of all human pathogens.
  • WNV has now spread globally, with the first case in the Western Hemisphere being identified in New York City in 1999; over the next 5 years, the virus spread across the continental United States, north into Canada, and southward into the Caribbean Islands and Latin America.
  • WNV is now considered to be an endemic pathogen in Africa, Asia, Australia, the Middle East, Europe and in the United States, which in 2012 has experienced one of its worst epidemics.