MBIOS 101 1nd Edition Lecture 19 Outline of Last Lecture - Chemical Controls1. Terms2. Mechanisms of pathogenesis3. Invasion and portal of entryOutline of Current Lecture – 1. Exoenzyme2. Toxins3. Endotoxins4. ExotoxinsCurrent Lecture – Pathogenic Organisms1. Organisms produce exotoxins, endotoxins and enzymes2. Exoenzyme- produced and released by the organisma. Mucinase: destroy mucus, usually destroys the mucus so the organism can attachto the surfaceb. Leukocidins: destroy white blood cells c. Hemolysins: destroy red blood cellsd. Coagulase: forms blood clot or clot – some organism cause more clotting so that they are protected from the white blood cellse. Bacterial kinase: breaks down fibrin in blood clots – after hiding and when the coast is clear, the bacteria breaks free from clot f. Streptokinase: dissolves blood clotsg. Hyaluronidase: dissolves hyaluronic acid so the organism can spread – loosens skin from muscle can eventually lead to the skin falling off h. Collagenase: destroy collagen – if it gets in your nose cartilage then your nose can fall offi. Necrotizing factor: destroy tissue – wants to destroy cells—possibly because it cant live in presence of oxygen These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.j. Lecithinase: destroy cell membrane k. Protease: destroys protein l. Hypothermic factor: organism can change the temperature m. GOAL: They create these to make the environment that they need3. Toxins a. Exotoxins- make inside and send out of the cell (Gram positive cells) b. Endotoxins- Gram negative cell walli. When a Gram negative cell is dying, the LPS layer produces an endotoxin Property Exotoxin EndotoxinBacterial Source Mostly Gram positive Mostly Gram negativeChemistry Metabolic product Present in LPS of outer membrane of cell wall and realsed when dyingPharmacology Specific for particular cell structureGeneral – weakness, fatigue, full body shutdownHeat Stability Unstable – destroyed usually at 60-80º C except staph enterotoxinStable – can withstand autoclaving Toxicity (Cause Disease) High Lows Fever producing No Yes Immunization Can be converted to toxoids to immunize against toxins neutralized by antitoxinNot easily neutralized by antitoxin, therefore toxoids cannot be made to immunize against it Lethal Dose Small Considerably largeRepresentative Diseases Gas gangrene, tetanis, botulism, diptheira, scarlet feverTyphoid fever, urinary tract infection, and meningococcal meningititsToxins (all exotoxins) Name of Disease; name of toxinsCharacteristics of diseaseClostridium botulinum Botulism; botulinum toxin Attacks the synapses betweenthe nerve and the muscle (blocks it )—causes muscles tospasm and lock (lock jaw up tofull body contracture) Flaccid paralysisClostridium tetani Tetanus; tetanospasm Spastic paralysis (botox) Targets your diaphragm
View Full Document
Unlocking...