Flashcards
Bacterial Infections
Flashcards do conjunto (37)
- 1Give the 3 methods of bacterial entry through the skinActive penetration using enzymes
Passive penetration through wounds, hair follicles or sweat glands
Via arthropod vectors - 2Give an example of a bacteria that enters the skin via active penetrationBrucella
- 3Why is active penetration through the skin rare?Enzymes are highly energy expensive
- 4Give an example of a bacteria that commonly enters through woundsStaphylococcus
- 5Why do some bacteria require an arthropod vector?Poor survival in the environment
- 6Describe bacterial entry at mucous membranesMucinase (neuraminidase) digests mucin
Motility/ chemotaxis towards nutrients
Release of iron-binding siderophores
Adhesin binding to prevent mucous removing bacteria - 7Give an example of nutrients that are chemotactic to bacteriaLipids and glycoprotein in the cell membrane
- 8What are the 2 types of non-specific adhesins?Hydrophilic
Hydrophobic - 9Give 3 examples of specific adhesinsLipoteichoic acid
Capsular material
Fimbrial proteins - 10Why do the bronchi have only a transient (not resident) bacterial population?Cilia
- 11What are 2 ways that bacteria can prevent their removal by cilia?Ciliostatic products = prevents activity of cilia
Ciliotoxic products = destroys cilia - 12How are some bacteria able to survive in the urinary tract despite the high concentration of urea?Produce the enzyme urease
Breaks down urea into ammonia and carbon dioxide - 13What is the target molecule and target site of the bacterial enzyme collagenase?Collagen
Tissue matrix - 14What is the target molecule and target site of the bacterial enzyme elastase?Elastin
Tissue matrix - 15What is the target molecule and target site of the bacterial enzyme hyaluronidase?Hyaluronic acid
Tissue matrix - 16What is the target molecule and target site of the bacterial enzyme lecithinase?Lecithin (phospholipid)
Cell membrane - 17What is the target molecule and target site of the bacterial enzyme DNAse?DNA
Intracellular - 18What is the least specific site of bacterial entry?Wounds - almost all bacteria can produce site specific wound infections
- 19What does dichelobacter nodosus digest?Causes footrot
Produces enzymes to digest the foot because it is anaerobic - 20Is strepococcus pyogenes commensal or pathogenic?Usually commensal
However, can become pathogenic and infect wounds (usually in immuno-compromised) - 21Why do clostridial species cause necrosis and blackleg?Disrupt blood supply because they are anaerobic
- 22What are 3 advantage to bacteria of entry inside a host cell?Cannot be detected by the immune system
Nutrient provision
Protected replication - 23Give the 3 stages of bacterial entry into host cellsAdhesins attach to target cell
Stimulate endocytosis
Intracellular survival - 24How do bacteria stimulate their own endocytosis?Once adhesins attach to cell, inject proteins that alter the host cell actin cytoskeleton
Cell membrane 'ruffles' form and endocytose bacteira - 25Which 2 cell types are major targets of bacterial invasion?Epithelial cells
Macrophages - 26What are the 2 routes of bacterial entry into a host cell?Endocytosis
Phagocytosis - 27Which is the more efficient route of entry into a host cell?Endocytosis more efficient than waiting to be phagocytosed
- 28Give an example of a bacterium that enters the host cell by stimulating endocytosisSalmonella (and many other GI bacteria)
- 29How do bacteria appear within an invaded cell?Vacuolated within cell
- 30Why is bacterial replication inside epithelial cells or macrophages likely to cause systemic infection?Can disseminate throughout the body
- 31What is the term for a vacuole within a cell containing a bacterium?Endosome
- 32What is the name for vesicles produced by host cells to kill endocytosed bacteria?Lysosomes
- 33Give 3 mechanisms for intracellular survival of bacteriaBacterial enzyme (e.g. phospholipase) allows escape from the endosome
Bacterial surface components inserted into endosome membrane to block lysosome fusion
Bacterial survival in endolysosome - 34What is the name of the process by which bacteria exit the cell and infect more deeply?Transcytosis
- 35In which animals is bacterial exit from cell to infect more deeply common?Immunocompromised individuals
Normally the antibody response will prevent bacterial adhesins binding to a cell membrane in the first place - 36How does bacterial entry into macrophages occur?Adhere to epithelium and wait to be phagocytosed
- 37When is systemic infection by bacteria more common?Large numbers invade at once e.g. through a cut in the epithelium, meaning the immune system is overwhelmed
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- Animal Disease 1 (Agents of Disease) FlashCards sobre Bacterial Infections, criado por Florence Edwards em 09-12-2016.
- Criado por
- Florence Edwards
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