Flashcards in Virulence in bacteria Deck (69)
symbiosis that is beneficial to both organisms involved., relation is positive for both organisms
is a class of relationships between two organisms where one organism benefits from the other without affecting it. Good for one, no problem for the other (most intestinal flora)
non-mutual symbiotic relationship between species, where one species, the parasite, benefits at the expense of the other, the host. One takes advantage of the other
Invasion and multiplication of micro-organisms
Causes structural and functional damage
E. Coli O157: H7 use this type of motility along with H-antigens, Listeria mnocytogenes (Not in all bacteria, mainly in gram - bacteria)
Flagella is composed of?
Pili+fimbriae (which are the same thing) came together to be known as ?
Used mainly for adhesion by F-antigens
Bacterial conjugation use this for plasmid transfer
Special pili known as sex pili
parasites are capable of living and reproducing either inside or outside cells. ( cause Cell lysis)
cannot reproduce outside their host cell, meaning that the parasite's reproduction is entirely reliant on intracellular resources. (cause Cell lysis)
Extracellular _________ -attach to the heart, parasites take over local use of nutrients oxygen
Extracellular immunological reaction is when?
macrophages and neutrophils produce oxygen radicals/ enzymes to kill the host cell
During invasion, what virulence factors are involved?
- need to haveProteins that circumvent innate immunity or they will be killed off
-Iron uptake for growth (body hides iron from bacteria) bacteria have to counteract that to have iron for own metabolism
-Production of extracellular enzyme like
-Not in all bacteria
-composed of Polysaccarides-proteins
- is a Virulence factor
d. Protection against phagocytosis and complement
-Environmental protection (spore formation)
-K antigens of the cell
Bacterial metabolites like Clostridium, high molecular weight-->vaccination (thus antigenic)
Type I, II, III
chemically treated (formalin) toxin
toxic effect goes down, antigenicity +vacination goes up
is the capacity of a chemical structure (either an antigen or Hapten) to bind specifically with a group of certain products that have adaptive immunity: T cell receptors or antibodies (a.k.a. B cell receptors).
Type of exotoxin that binds receptor, disturbance of cell metabolism.
Examples: STa ETEC, clostridium perfringens, Staphylococco, Streptococci
Type 1 exotoxin
type of exotoxin where there is cell wall damage. staphylococcus aureus (alfa toxin-hemolysis), Actinobacillus pleuropneumoniae (pore forming)-makes holes in cell through cell lysis
Type II exotoxin
Type of exotoxin that is intracellular toxins, A component goes intracellular (IC), B (binding) component binds membrane
Type III exotoxin
Examples of Type III exotoxin
-Heat labile toxin
Part of the cell wall in Gram +/- bacteria
Endotoxin (part of the cell wall)
Toxin that targets cell wall components and causes lots of damage and causes an immune reaction. LPS (heat stable) Causes fever, general sickness, tissue damage, cardiovascular shock, death
Endotoxin for Gram negative
Function of the lipopolysaccharide?
Protection against toxic products and complement activation. Acts as an endotoxin for infections with a gram negative bacterium
Endotoxin lipopolysaccharide is released by multiplication of membrane vesicles or they are released by "lysing" to get endotoxine release
Gram negative bacteria-->lipid A =Endotoxin----> ?
Complement activation causes?
Hageman factor causes?