Lecture 9: The Parasite’s Way of Life

200 Practice flashcards based on the lecture notes 'The Parasite’s Way of Life - Chapter 8', covering colonization, defense subversion, and transmission.

What is the title of Chapter 8 in 'The Parasite’s Way of Life'?

The Parasite’s Way of Life

What is the first step in the parasite's way of life?

Surface colonization

What is the second step in the parasite's way of life?

Finding a nutritionally compatible niche

What is the third step in the parasite's way of life?

Surviving host defenses

What is the fourth step in the parasite's way of life?

Intracellular life

What is the fifth step in the parasite's way of life?

Subverting host immune responses

What is the sixth step in the parasite's way of life?

Transmission to a new host

How do bacteria vary in their preference for particular locations in the body?

In specificity

What term describes the preference of bacteria for particular locations in the body?

Tissue tropism

What are located on the bacterium to facilitate tissue tropism?

Adhesins

What do bacterial adhesins interact with on the host side?

Receptors on host cell

What type of cellular structure is associated with adhesins in E. coli?

Fimbriae

Is E. coli a gram-positive or gram-negative bacterium?

Gram-negative

Where are bacterial proteins often located in gram-negative bacteria to interact with host cells?

On the tips of fimbriae and/or pili

What two types of host molecules do fimbrial proteins often interact with?

Glycolipids and/or glycoproteins

What specific host cells do fimbrial proteins typically interact with?

Host epithelial cells

Who are the authors of the 2003 J Cell Sci article cited regarding bacterial proteins?

Kris A. DeMali and Keith Burridge

In what year was the DeMali and Burridge article published in J Cell Sci?

$$2003$$

What volume was the 2003 J Cell Sci article published in?

$$116$$

What are the page numbers for the cited 2003 DeMali and Burridge article?

$$2389-2397$$

What are the bacterial surface proteins called that interact with TIR?

Intimins

What does the acronym TIR stand for?

Translocated intimin receptor

What type of bacteria utilizes the interaction between intimins and TIR?

Enteropathogenic E. coli

Where is the TIR receptor located before it interacts with intimins?

It is translocated to the host cell surface

According to the transcript, Staphylococcus aureus is which type of bacterium?

Gram-positive

What host molecule does Staphylococcus aureus often bind to?

Fibronectin

Where are the fibronectin-containing epithelial cells located relative to gram-positive bacteria binding?

Host fibronectin (epithelial cells) binds to integrins

What molecules do gram-positive epithelial cells' fibronectin bind to?

Integrins

What is the definition of fibronectin binding proteins in the context of bacterial adhesins?

A subclass of a large family of bacterial adhesins referred to as MSCRAMMS

What does the acronym MSCRAMMS stand for?

Microbial Surface Components Recognizing Adhesive Matrix Molecules

Besides fibronectin, what other target does MSCRAMMS recognize?

Fibrinogen

What is a third target recognized by MSCRAMMS besides fibronectin and fibrinogen?

Collagen

What condition in individuals in poor health shifts the balance in favor of gram-negative bacteria?

Fibronectin-deficient

What is a consequence of being fibronectin-deficient for individuals in poor health?

Greater incidence of pneumonias caused by gram-negative bacteria

What is the DOI for the 2015 Int J Mol Sci article mentioned in the notes?

$$10.3390/ijms16022626$$

What are the SRRPs found in gram-positive bacteria?

Serine rich repeat proteins

What do SRRPs contain thousands of in their domain?

Alternating serine residues

What is the unique domain extended by SRRPs called?

Non-repeat (NR) domain

What is the function of the NR domain in SRRPs?

It mediates adhesion

Which specific acid moieties do NR domains bind to?

Sialic acid

Besides sialic acid, what other molecule do NR domains bind to?

Keratin

Can NR domains bind to other NR domains of a similar SRRP?

Yes

Oral bacteria are mentioned as examples for which type of colonization process?

Surface colonization (continued)

Sialic acid binding adhesins in Streptococcus and Staphylococcus are classified as what?

Serine rich repeat proteins (SRRPs)

In what month and year was the Mol Oral Microbiol paper published regarding SRRPs?

August $2012$

What is the volume and issue number for the 2012 Mol Oral Microbiol article?

Vol $27$, Issue $4$

What are the page numbers for the 2012 Mol Oral Microbiol article?

$$257-269$$

What is a challenge for some bacteria regarding food availability?

Intermittent availability of food

Which specific bacteria are given as an example of having intermittent food availability?

Intestinal bacteria

What must bacteria do relative to a particular location for nutritional success?

Adaptation

What are the three components listed for the activation of complement?

$C5a$, $C3a$, and $C3b$

What is the role of $C5a$ in host defense?

It is a chemotactic protein for neutrophils and an anaphylatoxin

What is the role of $C3a$ in host defense?

It is an anaphylatoxin and inducer of acute inflammation

What are the roles of $C3b$?

It is an opsonin and part of $C3$ convertase and $C5$ convertase

In which chemical pathway is $C3b$ part of the $C3$ convertase?

Alternative pathway

What does MAC stand for in complement defense?

Membrane attack complex

How does Salmonella limit the access of MAC to its surface?

Using long-chain 'smooth' LPS

What abbreviation is used for lipopolysaccharide in Salmonella defense?

LPS

How does Streptococcus defend against the complement component $C3b$?

It produces $C3b$ peptidase

What is the function of $C3b$ peptidase?

It cleaves the complement component into inactive $C3b$ fragments

What does gonococcus add to its lipooligosaccharide to inhibit complement fixation?

Sialic acid ($SA$)

What is the full name of the component abbreviated as SA?

Sialic acid

What structure in meningococcus masks surface components from activating the alternate pathway?

Polysaccharide capsule

Which organism protects itself from complement using a polysaccharide capsule?

Meningococcus

What is subverting phagocytosis primarily about?

Inhibiting phagocyte recruitment and function

What attract neutrophils toward a site of infection?

A gradient

What enzyme is produced to inhibit neutrophil recruitment?

$C5a$ peptidase

Increasing which molecule to inhibitory levels subverts phagocytosis?

$$cAMP$$

What are the toxins called that kill phagocytes?

Leukocidins

What bacterial protein helps organisms escape ingestion by Staphylococci and Streptococci?

Protein A

Where is Protein A expressed?

On the bacterial cell surface

To which part of the immunoglobulin molecule does Protein A bind?

Fc portion of $IgG$

Why is the binding of Protein A to the Fc portion a problem for the host?

It binds the 'wrong end,' so the antibodies cannot act as opsonins

What are the four ways bacteria survive inside phagocytes?

Inhibit lysosomal fusion, escape into cytoplasm, resist enzymes, inhibit oxidative pathway

How do bacteria escape into the cytoplasm from a phagosome?

They form pores in the phagosome

What specific host pathway is inhibited to prevent a 'respiratory burst'?

Phagocyte’s oxidative pathway

What is another term for the phagocyte's oxidative pathway?

Respiratory burst

What do bacteria prevent from fusing with the phagosome?

Lysosomal fusion

What bacterial surface proteins interact with host integrins during penetration?

Invasins

What bacterial surface proteins interact with host E-cadherin?

Internalins

What host molecule does an internalin interact with?

E-cadherin

How do some bacteria enter nonphagocytic host cells?

By stimulating host cell membrane protrusion

What is the title of Figure 8-2?

Actin-dependent intracellular motility and intercellular spread

Intracellular life involves which two transmission-related activities?

Tissue damage and cell-to-cell transmission

On what process does intracellular motility and intercellular spread depend?

Actin-dependent motility

What are the four methods listed for subverting immune responses?

Immunosuppression, superantigens, changing antigenic coats, and proteolysis of antibodies

How do superantigens subvert the immune response?

By diverting lymphocyte function

What is the specific description for Figure 8-3?

Superantigen-mediated T cell activation

Which organism is noted for changing its antigenic coats?

Borrelia

What does proteolysis of antibodies accomplish for the parasite?

Subverting immune responses

Judgment of transmission can be described as what two types?

Passive or active

The judgment of transmission as passive or active is described as being what?

Arbitrary

What should be considered when judging the type of transmission?

Effects on host

What are three examples of transmission symptoms or methods?

Sneezing and coughing, diarrhea, and insects

What is the source URL provided for sneezing and coughing notes?

https://calwalkerful.wordpress.com/2015/08/08/some-curmudgeonly-comments-on-sneeze-blessings/

What is the source URL provided for the mosquito image?

https://upload.wikimedia.org/wikipedia/commons/1/11/Mosquito_Tasmania_crop.jpg

What is the source URL provided for chronic diarrhea notes?

http://www.pyroenergen.com/articles11/images/chronic-diarrhea2.jpg

What molecule is $C3a$ categorized as besides an inducer of inflammation?

Anaphylatoxin

According to Figure 8-1, what masks surface components to prevent alternate pathway activation?

Polysaccharide capsule

What bacterial genus is associated with $C3b$ peptidase?

Streptococcus