p.57
Bacterial Virulence Factors
What are exotoxins?
Toxins produced by bacteria that cause damage.
p.4
Pathogenesis of Bacterial Infection
What leads to the occurrence of disease in bacterial infections?
Disease occurs if the bacteria or immune reactions cause sufficient harm to the person.
p.14
Mechanisms of Bacterial Adherence and Invasion
What do bacteria attach to in the body?
Host cells, usually epithelial cells.
p.20
Pathogenesis of Bacterial Infection
What are Pathogenicity Islands?
Large groups of genes associated with pathogenicity.
p.5
Mechanisms of Bacterial Adherence and Invasion
What role does adherence play in the infection process?
It is the initial step in the infection process after bacteria enter the body.
p.44
Immune Evasion Strategies of Bacteria
What is antigenic mimicry in bacteria?
Bacterial antigens mimic the antigens found on host tissues.
p.28
Bacterial Virulence Factors
What are bacterial virulence factors?
Characteristics that enable bacteria to cause disease.
p.21
Bacterial Virulence Factors
What is the role of colonization in bacterial virulence?
It allows bacteria to establish themselves in the host environment.
p.4
Clinical Implications of Bacterial Infections
What does it mean when bacterial infections are described as asymptomatic?
It means that many bacterial infections do not show symptoms.
p.12
Natural Defense Mechanisms Against Bacterial Infections
What is one natural defense mechanism found in the upper respiratory tract?
Mucus and ciliated epithelium.
p.17
Genetic Exchange and Pathogenicity in Bacteria
What are plasmids?
Extrachromosomal pieces of DNA capable of replicating.
p.2
Pathogenesis of Bacterial Infection
What is the first step in the pathogenesis of bacterial infection?
Initiation of the infectious process.
p.51
Bacterial Virulence Factors
What are endotoxins?
Components of the outer membrane of Gram-negative bacteria that can induce immune responses.
p.7
Mechanisms of Bacterial Adherence and Invasion
What is the definition of invasion in microbiology?
The process whereby microorganisms enter host cells or tissues and spread in the body.
p.6
Pathogenesis of Bacterial Infection
What is an infection?
Multiplication of an infectious agent within the body, even if the person is asymptomatic.
p.6
Pathogenesis of Bacterial Infection
What defines an infectious disease?
Clinically evident illness resulting from infection, characterized by medical signs and/or symptoms.
p.32
Bacterial Virulence Factors
On what types of surfaces does biofilm commonly facilitate bacterial colonization?
On surgical appliances like artificial valves and catheters.
p.15
Pathogenesis of Bacterial Infection
How does bacteremia facilitate bacterial infection?
It allows bacteria to reach tissues for multiplication.
p.21
Bacterial Virulence Factors
What are bacterial virulence factors?
Traits that enable bacteria to colonize, evade the immune response, and damage the host.
p.15
Pathogenesis of Bacterial Infection
What is a key aspect of the infectious process related to bacteremia?
The ability of bacteria to disseminate throughout the body.
p.10
Transmission Routes of Pathogenic Bacteria
What is one portal of entry for pathogenic bacteria?
Respiratory tract (upper and lower airways).
p.26
Bacterial Virulence Factors
What is the role of pili in bacterial virulence?
They enable attachment to host receptors.
p.5
Mechanisms of Bacterial Adherence and Invasion
What is adherence in the context of bacterial infection?
The process by which bacteria stick to the surfaces of host cells.
p.32
Bacterial Virulence Factors
What is the role of biofilm in bacterial colonization?
Facilitates colonization of bacteria, especially on surgical appliances.
p.57
Bacterial Virulence Factors
How do Gram-negative bacteria release their toxins?
Through one of the secretion systems.
p.62
Bacterial Virulence Factors
What is one function of pore-forming toxins?
Releasing nutrients and causing death of host cells.
p.56
Bacterial Virulence Factors
What controls toxin synthesis in bacteria?
It can be controlled by chromosome or plasmid.
p.39
Bacterial Virulence Factors
How does the capsule inhibit the formation of C3 convertase?
By preventing the activation of the complement system.
p.16
Genetic Exchange and Pathogenicity in Bacteria
What is natural transformation in bacteria?
A process where bacteria take up free DNA from their environment.
p.62
Bacterial Virulence Factors
What effect do pore-forming toxins have on vacuole membranes?
They damage vacuole membranes, allowing bacteria to escape into the cytoplasm.
p.59
Bacterial Virulence Factors
What is the role of IL-2 in the immune response?
It stimulates the activation and proliferation of T cells.
p.34
Bacterial Virulence Factors
What happens to bacteria after internalization during invasion?
They can either persist in an intracellular vacuole or escape to the cytosol.
p.43
Bacterial Virulence Factors
What is the significance of opsonization in the immune response?
It enhances the phagocytosis of pathogens by marking them for destruction.
p.14
Pathogenesis of Bacterial Infection
What happens after bacteria establish a primary site of infection?
They multiply and spread.
p.15
Pathogenesis of Bacterial Infection
What is bacteremia?
The presence of bacteria in the bloodstream.
p.8
Characteristics of Pathogenic Bacteria
What defines an opportunistic pathogen?
A microorganism that can cause disease only when the host’s immune system is impaired.
p.31
Bacterial Virulence Factors
What is a biofilm in the context of bacterial virulence?
An aggregate of interactive bacteria attached to a solid surface or to each other and encased in an exopolysaccharide matrix.
p.2
Pathogenesis of Bacterial Infection
What do mechanisms in bacterial pathogenesis lead to?
The development of signs and symptoms of disease.
p.51
Bacterial Virulence Factors
What is the role of O-specific polysaccharide in endotoxins?
It induces specific immunity (O-antigen).
p.27
Bacterial Virulence Factors
What happens to pili once bacteria adhere to the host cell?
Pili depolymerize, enabling bacteria to attach more securely.
p.40
Bacterial Virulence Factors
How does the capsule contribute to bacterial virulence?
By helping bacteria evade the complement system.
p.17
Genetic Exchange and Pathogenicity in Bacteria
What are bacteriophages?
Viruses that transfer DNA from phage to the bacterium.
p.64
Bacterial Virulence Factors
What is the function of the 'A' subunit in A-B toxins?
'A' subunit is the active site that exhibits various effects.
p.43
Bacterial Virulence Factors
What is the effect of IgM and IgA on bacteria?
They cause bacteria to aggregate and facilitate their phagocytosis.
p.64
Bacterial Virulence Factors
What is the role of the 'B' subunit in A-B toxins?
'B' subunit serves as the binding site.
p.10
Transmission Routes of Pathogenic Bacteria
What are two other portals of entry for pathogenic bacteria?
Genital and urinary tracts.
p.29
Bacterial Virulence Factors
What is a key bacterial virulence factor related to colonization?
Adherence through a polysaccharide capsule (glycocalyx).
p.35
Bacterial Virulence Factors
Where is most of the iron located in the host?
Intracellularly, in hemoglobin and myoglobin.
p.35
Bacterial Virulence Factors
What is the concentration of free iron in its ferric form (Fe 3+) in the host?
Very low due to transferrin and lactoferrin.
p.8
Characteristics of Pathogenic Bacteria
What is a pathogen?
A microorganism capable of causing disease.
p.17
Genetic Exchange and Pathogenicity in Bacteria
What are transposons?
Highly mobile segments of DNA.
p.53
Types of Toxins: Exotoxins and Endotoxins
What are endotoxins?
Components of the outer membrane of Gram-negative bacteria that can trigger strong immune responses.
p.61
Bacterial Virulence Factors
What effect do Type II exotoxins have on membranes?
They have a detergent-like effect.
p.31
Bacterial Virulence Factors
Where can biofilms occur?
Throughout nature, on solid surfaces or among each other.
p.12
Natural Defense Mechanisms Against Bacterial Infections
How does ciliated epithelium contribute to defense in the respiratory tract?
It helps move mucus and trapped particles out of the airways.
p.65
Bacterial Virulence Factors
What are bacterial virulence factors?
Traits that enable bacteria to colonize, escape the host immune response, and cause damage.
p.38
Bacterial Virulence Factors
What role do cytokines play in bacterial infections?
They are secreted by macrophages and can activate the complement system.
p.50
Bacterial Virulence Factors
How do endotoxins contribute to bacterial virulence?
By producing damage to the host.
p.35
Bacterial Virulence Factors
Why is iron considered essential for bacteria?
It is crucial for a variety of metabolic functions due to its wide oxidation-reduction potential.
p.44
Immune Evasion Strategies of Bacteria
What proteins do several bacteria coat their surfaces with?
Host proteins such as fibronectin, lactoferrin, and transferrin.
p.44
Immune Evasion Strategies of Bacteria
How do bacteria evade opsonization?
By binding to the Fc region of antibodies, preventing opsonization despite being coated with antibodies.
p.33
Mechanisms of Bacterial Adherence and Invasion
What is another method by which bacteria can invade host cells?
By directly entering the host cells.
p.59
Bacterial Virulence Factors
What are some symptoms caused by IL-2?
Fever, vomiting, diarrhea, malaise.
p.51
Bacterial Virulence Factors
What is common about the core polysaccharide in Gram-negative bacteria?
It is the same in all Gram-negative bacteria.
p.21
Bacterial Virulence Factors
What does producing damage in the host entail?
It involves causing harm to host tissues and disrupting normal physiological functions.
p.58
Bacterial Virulence Factors
How do superantigens differ from normal antigens in their interaction with MHC II?
Superantigens directly bind to MHC II, bypassing the normal antigen presentation process.
p.63
Bacterial Virulence Factors
What happens to 'Part A' after entering the host cell?
'Part A' transfers into the cytoplasm.
p.24
Types of Toxins: Exotoxins and Endotoxins
What is an endotoxin?
A toxin that is part of the bacterial cell wall and is released upon cell lysis.
p.42
Bacterial Virulence Factors
What is MAC in the context of bacterial virulence?
Membrane Attack Complex, which bacteria can inhibit.
p.37
Bacterial Virulence Factors
How do some bacteria escape from adaptive immunity?
Through antigenic shift and antigenic mimicry.
p.52
Bacterial Virulence Factors
What are some clinical findings associated with LPS in the bloodstream?
Fever, leukopenia, hypoglycemia, hypotension, and shock.
p.1
Clinical Implications of Bacterial Infections
What department does Emrah Ruh work in?
Department of Medical Microbiology and Clinical Microbiology.
p.33
Mechanisms of Bacterial Adherence and Invasion
How do some bacteria invade tissues?
Through the junctions between epithelial cells.
p.60
Bacterial Virulence Factors
What are the effects of the cytokines released by IL-2?
Endothelial damage, acute respiratory distress syndrome, DIC, shock, and organ dysfunction.
p.43
Bacterial Virulence Factors
How do IgG and IgM contribute to the immune response?
They activate the complement system via the classical pathway.
p.28
Bacterial Virulence Factors
What are adhesins?
Molecules that enable bacteria to attach to host receptors.
p.38
Bacterial Virulence Factors
What is phagocytosis in the context of bacterial virulence?
A process where macrophages engulf and digest bacteria, leading to cytokine secretion.
p.16
Genetic Exchange and Pathogenicity in Bacteria
What are plasmids?
Small, circular DNA molecules that can replicate independently of chromosomal DNA in bacteria.
p.66
Bacterial Virulence Factors
What is the role of adhesins in bacterial infections?
They facilitate adherence to host tissues.
p.36
Bacterial Virulence Factors
What are siderophores?
Molecules specific for ferric iron that supply iron to the bacterial cell.
p.34
Bacterial Virulence Factors
What are the two fates of bacteria after they invade a host cell?
Persist in an intracellular vacuole or escape to the cytosol.
p.14
Transmission Routes of Pathogenic Bacteria
How can bacteria spread after establishing an infection?
Directly through tissues or via the lymphatic system to the bloodstream.
p.57
Bacterial Virulence Factors
How do Gram-positive bacteria release their toxins?
Directly into the environment.
p.8
Characteristics of Pathogenic Bacteria
What is a nonpathogen?
A microorganism that does not cause disease and may be part of the normal flora.
p.32
Bacterial Virulence Factors
How does biofilm contribute to bacterial resistance?
It enables resistance to the host immune system and antibiotics.
p.56
Bacterial Virulence Factors
What are exotoxins?
Toxins produced by bacteria that cause damage to host tissues.
p.60
Bacterial Virulence Factors
What does IL-2 trigger the release of?
Several cytokines including TNF-a, IL-1, IL-8, and PAF.
p.61
Bacterial Virulence Factors
What activities are associated with Type II exotoxins?
Phospholipase C, phospholipase D, and sphingomyelinase activity.
p.13
Natural Defense Mechanisms Against Bacterial Infections
What can compromise the body's barriers?
Cuts, burns, and other injuries in the skin; tumors or ulcers in the bowel.
p.35
Bacterial Virulence Factors
What are the three main steps in bacterial virulence factors?
Colonization, Invasion, Nutrition.
p.65
Bacterial Virulence Factors
What is the role of colonization in bacterial virulence?
It allows bacteria to establish themselves in the host environment.
p.9
Bacterial Virulence Factors
What is pathogenicity?
The ability of an infectious agent to cause disease.
p.20
Genetic Exchange and Pathogenicity in Bacteria
Where are Pathogenicity Islands located?
On the bacterial chromosome.
p.15
Pathogenesis of Bacterial Infection
What does bacteremia allow bacteria to do?
Spread widely in the body.
p.56
Bacterial Virulence Factors
How is exotoxin synthesis generally enabled?
By genetic information transferred by plasmid or phage.
p.61
Bacterial Virulence Factors
What are Type II exotoxins?
Membrane damaging toxins that hydrolyze membrane phospholipids.
p.59
Bacterial Virulence Factors
What stimulates the release of large amounts of IL-2?
Activation of large amounts of T4 lymphocytes.
p.21
Immune Evasion Strategies of Bacteria
How do bacteria escape from the host immune response?
By employing various strategies to avoid detection and destruction by the immune system.
p.50
Types of Toxins: Exotoxins and Endotoxins
What is the primary component of endotoxins?
Lipopolysaccharide (LPS).
p.61
Bacterial Virulence Factors
What is a characteristic feature of channel or pore-forming toxins?
They create pores in cell membranes, leading to cell damage.
p.16
Genetic Exchange and Pathogenicity in Bacteria
How do bacteriophages contribute to genetic exchange in bacteria?
They can transfer genetic material between bacteria during the process of infection.
p.66
Bacterial Virulence Factors
What is a biofilm in the context of bacterial virulence?
A structured community of bacteria that enhances survival and resistance.
p.25
Bacterial Virulence Factors
What is the role of adhesins in bacterial infections?
They facilitate adherence to host tissues.
p.30
Bacterial Virulence Factors
What dental condition is associated with bacterial virulence factors?
Formation of dental caries.
p.67
Bacterial Virulence Factors
How do bacteria protect themselves against neutrophils?
By escaping from the phagosome.
p.45
Types of Toxins: Exotoxins and Endotoxins
What are superantigens?
A class of Type I exotoxins that activate a large number of T cells, leading to a strong immune response.
p.48
Types of Toxins: Exotoxins and Endotoxins
How do endotoxins affect fever in hosts?
They usually produce fever by the release of interleukin-1 and other mediators.
p.45
Types of Toxins: Exotoxins and Endotoxins
What are Type III toxins?
A-B toxins that consist of an active (A) and a binding (B) component.
p.47
Bacterial Virulence Factors
Can endotoxins be converted to toxoids?
No, endotoxins are not converted to toxoids.
p.24
Types of Toxins: Exotoxins and Endotoxins
What are Type III toxins?
A-B toxins that consist of two components: an A (active) component and a B (binding) component.
p.55
Types of Toxins: Exotoxins and Endotoxins
What are Type II toxins?
Membrane damaging toxins that disrupt the integrity of host cell membranes.
p.23
Bacterial Virulence Factors
What mechanism do bacteria use to inhibit complement activation?
Inhibition of the membrane attack complex (MAC).
p.23
Bacterial Virulence Factors
What is antigenic mimicry in the context of bacterial virulence?
When bacteria mimic host antigens to evade immune detection.
p.14
Mechanisms of Bacterial Adherence and Invasion
What is the first step in the infectious process for bacteria?
Attachment or adherence to host cells.
p.43
Bacterial Virulence Factors
What is the role of IgG in the immune response?
IgG acts as an opsonin and causes opsonization.
p.50
Types of Toxins: Exotoxins and Endotoxins
What are endotoxins?
Lipopolysaccharides (LPS) that are endotoxins of Gram-negative bacteria.
p.27
Bacterial Virulence Factors
What is the role of pili in bacterial virulence?
Pili facilitate adherence to host cells by being compatible with glycoprotein and glycolipid receptors.
p.31
Bacterial Virulence Factors
What is the role of biofilms in bacterial colonization?
They form a slimy coat on solid surfaces and facilitate adherence.
p.12
Natural Defense Mechanisms Against Bacterial Infections
What role does mucus play in the respiratory tract?
It helps trap pathogens and particles.
p.64
Types of Toxins: Exotoxins and Endotoxins
What are A-B toxins?
Exotoxins consisting of an active 'A' subunit and a binding 'B' subunit.
p.22
Bacterial Virulence Factors
What is the role of adhesins in bacterial infections?
They facilitate adherence to host tissues.
p.39
Bacterial Virulence Factors
What role does binding protein H play in relation to bacterial capsules?
It helps in evading the immune response, especially in capsules rich in sialic acid.
p.49
Types of Toxins: Exotoxins and Endotoxins
What are endotoxins?
Lipopolysaccharides (LPS) that are endotoxins of Gram-negative bacteria.
p.53
Bacterial Virulence Factors
How do endotoxins contribute to bacterial virulence?
By causing damage to host tissues and triggering inflammatory responses.
p.13
Characteristics of Pathogenic Bacteria
What is a characteristic of the outer membrane of Gram-negative bacteria?
Resistance to lysozyme, acid, and bile.
p.39
Bacterial Virulence Factors
What does masking pathogen-associated molecular patterns achieve?
It helps the bacteria evade detection by the immune system.
p.62
Bacterial Virulence Factors
What type of toxins are classified as membrane-damaging toxins?
Exotoxins, specifically Type II: Membrane damaging toxins.
p.53
Types of Toxins: Exotoxins and Endotoxins
What is a key characteristic of endotoxins compared to exotoxins?
Endotoxins are heat-stable and not secreted, while exotoxins are often heat-labile and secreted by bacteria.
p.65
Bacterial Virulence Factors
What does producing damage in the host entail?
It involves harming host tissues or disrupting normal physiological functions.
p.9
Bacterial Virulence Factors
What is toxigenicity?
The ability of a microorganism to produce a toxin.
p.42
Bacterial Virulence Factors
How do bacteria escape from adaptive immunity?
Through mechanisms like antigenic shift and antigenic mimicry.
p.67
Bacterial Virulence Factors
How do bacteria escape from adaptive immunity?
Through mechanisms like antigenic shift and antigenic mimicry.
p.52
Bacterial Virulence Factors
What receptors do LPS interact with on immune cells?
Toll-like receptor 4 (TLR-4).
p.55
Bacterial Virulence Factors
What are bacterial virulence factors?
Factors that enable bacteria to damage the host.
p.42
Bacterial Virulence Factors
What is the function of immunoglobulin proteases in bacterial virulence?
They degrade antibodies, aiding in immune evasion.
p.54
Bacterial Virulence Factors
What role does LPS play in the activation of plasminogen?
LPS activates plasminogen to plasmin, which converts fibrin to fibrin split products.
p.37
Bacterial Virulence Factors
How do bacteria trigger macrophage apoptosis?
By using specific virulence factors.
p.37
Bacterial Virulence Factors
What is the significance of binding to the Fc region of antibodies?
It helps bacteria evade opsonization and phagocytosis.
p.55
Types of Toxins: Exotoxins and Endotoxins
What is the function of the A component in A-B toxins?
It is responsible for the toxic effect.
p.23
Bacterial Virulence Factors
What is one way bacteria can trigger macrophage apoptosis?
By releasing specific factors that induce cell death.
p.68
Bacterial Virulence Factors
What are bacterial virulence factors?
Factors that enable bacteria to damage the host.
p.28
Bacterial Virulence Factors
What role do adhesins play in bacterial infections?
They facilitate the attachment of bacteria to host cells.
p.22
Bacterial Virulence Factors
What is a biofilm in the context of bacterial virulence?
A structured community of bacteria that enhances survival and resistance.
p.49
Bacterial Virulence Factors
How do endotoxins contribute to bacterial virulence?
By producing damage to the host.
p.29
Bacterial Virulence Factors
What role does glycosyltransferase play in bacterial adherence?
It converts glucose on the tooth surface to dextran, a component of glycocalyx.
p.3
Mechanisms of Bacterial Adherence and Invasion
What does adherence to host cells refer to?
The ability of pathogenic bacteria to attach to the cells of the host.
p.3
Mechanisms of Bacterial Adherence and Invasion
What is meant by invasion of host cells and tissues?
The ability of pathogenic bacteria to penetrate and multiply within host cells and tissues.
p.47
Bacterial Virulence Factors
What are the two main types of bacterial virulence factors discussed?
Exotoxins and endotoxins.
p.52
Bacterial Virulence Factors
What are endotoxins primarily composed of?
Lipopolysaccharides (LPS).
p.42
Bacterial Virulence Factors
How do bacteria protect themselves against neutrophils?
By inhibiting complement activation.
p.24
Types of Toxins: Exotoxins and Endotoxins
What are superantigens?
A class of Type I exotoxins that activate a large number of T cells, leading to a strong immune response.
p.37
Bacterial Virulence Factors
What mechanism do bacteria use to escape from the phagosome?
Inhibition of complement activation.
p.52
Bacterial Virulence Factors
What can result from impaired perfusion of essential organs due to LPS?
Intravascular coagulation and death from massive organ dysfunction.
p.48
Types of Toxins: Exotoxins and Endotoxins
What is a key difference in the genetic control of exotoxins and endotoxins?
Exotoxins are frequently controlled by extrachromosomal genes, while endotoxins are directed by chromosomal genes.
p.55
Types of Toxins: Exotoxins and Endotoxins
What are Type III toxins?
A-B toxins that consist of two components: an active component and a binding component.
p.68
Types of Toxins: Exotoxins and Endotoxins
What is an endotoxin?
A toxin that is part of the bacterial cell wall and is released upon cell lysis.
p.62
Bacterial Virulence Factors
How do pore-forming toxins function in relation to the type III secretion system?
They are involved in the functioning of the type III secretion system.
p.17
Genetic Exchange and Pathogenicity in Bacteria
What occurs during recombination involving extrachromosomal DNA?
Recombination between extrachromosomal DNA and the chromosome.
p.62
Bacterial Virulence Factors
What happens to the cell membrane due to pore-forming toxins?
They damage the cell membrane, allowing bacteria to leave the cell.
p.64
Bacterial Virulence Factors
What are some targets of A-B toxins?
Cyclic adenosine monophosphate (cAMP), ADP-ribosylation, Rho proteins, metalloproteinase action, and RNA.
p.63
Bacterial Virulence Factors
What are Type III exotoxins composed of?
Two subunits: 'A' and 'B'.
p.29
Bacterial Virulence Factors
Which bacterium is an example that causes tooth decay?
Bacteria that utilize glycosyltransferase to convert glucose to dextran.
p.9
Bacterial Virulence Factors
What role does virulence play in bacterial strains?
It differentiates the pathogenic strain of a species.
p.3
Types of Toxins: Exotoxins and Endotoxins
What is toxigenicity?
The ability of bacteria to produce toxins that can harm the host.
p.3
Immune Evasion Strategies of Bacteria
How do pathogenic bacteria evade the host's immune system?
By employing various strategies to avoid detection and destruction by immune cells.
p.45
Types of Toxins: Exotoxins and Endotoxins
What are Type I exotoxins?
Pyrogenic exotoxins that can induce fever.
p.48
Types of Toxins: Exotoxins and Endotoxins
What are exotoxins known for?
They usually bind to specific receptors on cells.
p.37
Bacterial Virulence Factors
What protects bacteria against neutrophils?
Capsule and other virulence factors.
p.37
Bacterial Virulence Factors
What is antigenic mimicry?
A strategy used by bacteria to evade the immune response by resembling host antigens.
p.23
Bacterial Virulence Factors
How do bacteria protect themselves against neutrophils?
By escaping from the phagosome and inhibiting neutrophil activity.
p.68
Types of Toxins: Exotoxins and Endotoxins
What are Type III toxins?
A-B toxins that consist of two parts: an active component and a binding component.
p.13
Mechanisms of Bacterial Adherence and Invasion
What do some bacteria have that allows them to invade the body?
Means to compromise the barrier.
p.31
Bacterial Virulence Factors
Can biofilms consist of multiple species?
Yes, they may consist of one or more species.
p.16
Genetic Exchange and Pathogenicity in Bacteria
What role do transposons play in bacterial genetics?
They are DNA sequences that can change their position within the genome, facilitating genetic variation.
p.38
Immune Evasion Strategies of Bacteria
What does 'escape from innate immunity' refer to?
Protection from phagocytosis and the lytic activity of the complement system.
p.64
Bacterial Virulence Factors
What is one effect of ADP-ribosylation by A-B toxins?
It modifies target proteins, affecting their function.
p.63
Bacterial Virulence Factors
What is the function of 'Part B' in Type III exotoxins?
'Part B' binds to the receptor of the host cell.
p.25
Bacterial Virulence Factors
What is a biofilm in the context of bacterial virulence?
A structured community of bacteria that enhances survival and resistance.
p.42
Bacterial Virulence Factors
What is the role of the capsule in bacterial virulence?
It helps bacteria evade the host's immune response.
p.67
Bacterial Virulence Factors
What is one way bacteria can trigger macrophage apoptosis?
By releasing specific factors that induce cell death.
p.55
Types of Toxins: Exotoxins and Endotoxins
What is an endotoxin?
A toxin that is part of the bacterial cell wall and is released upon cell lysis.
p.23
Bacterial Virulence Factors
How do bacteria escape from adaptive immunity?
Through mechanisms like antigenic shift and antigenic mimicry.
p.37
Bacterial Virulence Factors
What role do immunoglobulin proteases play in bacterial virulence?
They degrade antibodies, aiding in immune evasion.
p.68
Types of Toxins: Exotoxins and Endotoxins
What is the function of A-B toxins?
The A component is responsible for the toxic effect, while the B component binds to the host cell.
p.13
Mechanisms of Bacterial Adherence and Invasion
Can bacteria pass through the body's barriers?
Yes, bacteria can pass through the barriers.
p.41
Immune Evasion Strategies of Bacteria
What is inhibited to prevent phagosome formation?
Inhibition of phagosome formation.
p.3
Transmission Routes of Pathogenic Bacteria
What is transmissibility in the context of pathogenic bacteria?
The ability of bacteria to be spread from one host to another.
p.29
Bacterial Virulence Factors
How do bacteria adhere tightly to tooth enamel?
By using their glycocalyx.
p.41
Immune Evasion Strategies of Bacteria
What do bacteria develop to survive phagocytic death?
Resistance against phagocytic death.
p.67
Bacterial Virulence Factors
What mechanism do bacteria use to inhibit complement activation?
Inhibition of the membrane attack complex (MAC).
p.42
Bacterial Virulence Factors
How do bacteria bind to the Fc region of antibodies?
To prevent opsonization and enhance evasion of the immune response.
p.55
Types of Toxins: Exotoxins and Endotoxins
What are exotoxins?
Toxins secreted by bacteria that can cause damage to the host.
p.67
Bacterial Virulence Factors
What is the function of immunoglobulin proteases released by bacteria?
To degrade antibodies and impair the immune response.
p.55
Types of Toxins: Exotoxins and Endotoxins
What are superantigens?
A class of Type I exotoxins that activate a large number of T cells, leading to a strong immune response.
p.23
Bacterial Virulence Factors
What is the function of immunoglobulin proteases released by bacteria?
To degrade antibodies and evade the immune response.
p.65
Bacterial Virulence Factors
How do bacteria escape from the host immune response?
By employing various strategies to avoid detection and destruction by the immune system.
p.16
Genetic Exchange and Pathogenicity in Bacteria
What can result from the exchange of genetic information between bacteria?
The transfer of virulence factors.
p.10
Transmission Routes of Pathogenic Bacteria
How can pathogenic bacteria enter the body through the skin?
Through cuts or abrasions.
p.58
Bacterial Virulence Factors
What is the role of antigen presenting cells (APC) in normal conditions?
APCs present antigens to MHC II.
p.29
Bacterial Virulence Factors
What happens to bacterial cells of the same or different species in the glycocalyx?
They become entrapped and form plaque on the tooth surface.
p.45
Types of Toxins: Exotoxins and Endotoxins
What is an endotoxin?
A toxin that is part of the bacterial cell wall and is released upon cell lysis.
p.24
Types of Toxins: Exotoxins and Endotoxins
What are Type I exotoxins?
Pyrogenic exotoxins that can induce fever.
p.47
Bacterial Virulence Factors
How are toxoids related to exotoxins?
Toxoids are converted from exotoxins and are used to immunize.
p.54
Bacterial Virulence Factors
What are endotoxins associated with in bacterial infections?
They are associated with producing damage in the host.
p.54
Bacterial Virulence Factors
What is disseminated intravascular coagulation (DIC)?
A frequent complication of Gram-negative bacteremia that can also occur in other infections.
p.54
Bacterial Virulence Factors
How does LPS activate the coagulation cascade?
LPS activates factor XII, leading to the conversion of fibrinogen to fibrin.
p.48
Types of Toxins: Exotoxins and Endotoxins
Do endotoxins usually produce fever in hosts?
Yes, they usually produce fever, unlike exotoxins.
p.54
Bacterial Virulence Factors
What effect does LPS have on platelets?
LPS causes platelets to adhere to vascular endothelium, leading to occlusion of small blood vessels.
p.54
Bacterial Virulence Factors
What are the consequences of LPS-induced occlusion of small blood vessels?
It can cause ischemic or hemorrhagic necrosis in various organs.
p.23
Bacterial Virulence Factors
What is the role of the capsule in bacterial virulence?
It helps bacteria evade the host's immune response.
p.49
Types of Toxins: Exotoxins and Endotoxins
What is the primary component of endotoxins?
Lipopolysaccharide (LPS).
p.38
Bacterial Virulence Factors
How does the complement system relate to bacterial virulence?
It is activated by cytokines and the bacterium itself, which can lead to bacterial destruction.
p.41
Immune Evasion Strategies of Bacteria
What is one way bacteria escape from innate immunity?
By escaping from the phagosome.
p.9
Bacterial Virulence Factors
What does virulence refer to?
The quantitative ability of an agent to cause disease, involving adherence, invasion, and toxigenicity.
p.35
Bacterial Virulence Factors
Why is free iron in the ferric form (Fe 3+) considered highly insoluble?
Because it forms hydroxides, carbonates, and phosphates.
p.41
Immune Evasion Strategies of Bacteria
What process do bacteria inhibit to escape from the phagosome?
Inhibition of phagolysosome formation.
p.24
Types of Toxins: Exotoxins and Endotoxins
What are exotoxins?
Toxins secreted by bacteria that can cause damage to the host.
p.45
Types of Toxins: Exotoxins and Endotoxins
What are exotoxins?
Toxins secreted by bacteria that can cause damage to the host.
p.52
Bacterial Virulence Factors
Which cells are involved in the response to LPS?
Macrophages, monocytes, and other cells of the reticuloendothelial system.
p.47
Bacterial Virulence Factors
How do endotoxins differ in immunogenicity compared to exotoxins?
Endotoxins are weakly immunogenic, while exotoxins are highly antigenic.
p.67
Bacterial Virulence Factors
What is antigenic mimicry in the context of bacterial virulence?
When bacteria mimic host antigens to evade immune detection.
p.37
Bacterial Virulence Factors
What is the function of the Membrane Attack Complex (MAC) in the immune response?
To lyse bacterial cells, which some bacteria inhibit.
p.48
Types of Toxins: Exotoxins and Endotoxins
What is a characteristic of endotoxins regarding receptor binding?
Specific receptors are not found on cells for endotoxins.
p.68
Types of Toxins: Exotoxins and Endotoxins
What are exotoxins?
Toxins secreted by bacteria that can cause damage to the host.
p.68
Types of Toxins: Exotoxins and Endotoxins
What are Type II toxins?
Membrane damaging toxins that disrupt the integrity of host cell membranes.
p.41
Immune Evasion Strategies of Bacteria
How do bacteria resist the acidic environment of the phagosome?
By inhibiting phagosome acidification.
p.41
Immune Evasion Strategies of Bacteria
What is inhibited to prevent phagosome maturation?
Inhibition of phagosome maturation.
p.45
Bacterial Virulence Factors
What are bacterial virulence factors?
Factors that enable bacteria to damage the host.
p.67
Bacterial Virulence Factors
What is the role of the capsule in bacterial virulence?
It helps bacteria evade the host's immune response.
p.47
Bacterial Virulence Factors
What is the role of antitoxin in relation to exotoxins?
Antitoxin neutralizes the exotoxin.
p.42
Bacterial Virulence Factors
What is antigenic mimicry in bacterial virulence?
When bacteria mimic host antigens to evade immune detection.
p.68
Types of Toxins: Exotoxins and Endotoxins
What are superantigens?
A type of Type I exotoxin that activates a large number of T-cells, leading to a strong immune response.
p.24
Bacterial Virulence Factors
What are bacterial virulence factors?
Factors that enable bacteria to damage the host.
p.47
Bacterial Virulence Factors
How do exotoxins affect the immune system?
They are highly antigenic and stimulate the formation of high-titer antitoxin.
p.42
Bacterial Virulence Factors
What is one way bacteria can trigger macrophage apoptosis?
By releasing specific factors that induce cell death.
p.52
Bacterial Virulence Factors
What cytokines are released in response to LPS?
IL-1, TNF, and other cytokines.
p.45
Types of Toxins: Exotoxins and Endotoxins
What are Type II toxins?
Membrane damaging toxins that disrupt the integrity of host cell membranes.
p.67
Bacterial Virulence Factors
How do bacteria bind to the Fc region of antibodies?
To prevent opsonization and enhance evasion of the immune response.
p.55
Types of Toxins: Exotoxins and Endotoxins
What are Type I exotoxins?
Pyrogenic exotoxins that can induce fever.
p.24
Types of Toxins: Exotoxins and Endotoxins
What are Type II toxins?
Membrane damaging toxins that disrupt the integrity of host cell membranes.
p.55
Types of Toxins: Exotoxins and Endotoxins
What is the role of the B component in A-B toxins?
It binds to the host cell and facilitates the entry of the A component.
p.23
Bacterial Virulence Factors
How do bacteria bind to the Fc region of antibodies?
By using specific proteins that interfere with antibody function.
p.68
Types of Toxins: Exotoxins and Endotoxins
What are Type I exotoxins?
Pyrogenic exotoxins that can cause fever and immune response.
