Characterizing and Classifying Prokaryotes Exam - PDF

Characterizing and Classifying Prokaryotes – Exam 2 - Most the groups are based on morphology and physiology (form and function) - Examination of the phenotypic groupings of bacteria described in this chapter reveals the breadth of bacterial diversity - Difference between disease and...

Characterizing and Classifying Prokaryotes – Exam 2 - Most the groups are based on morphology and physiology (form and function) - Examination of the phenotypic groupings of bacteria described in this chapter reveals the breadth of bacterial diversity - Difference between disease and syndrome - disease will have signs and symptoms of specific disease, syndrome is signs of multiple diseases Gram-negative bacilli (enteric rods) 1. Escherichia coli i. Facultative anaerobe ii. Motile peritrichous flagella iii. Ferment lactose iv. Habitat/Transmission 1. Human colon (called coliform bacteria when in colon), vagina, and urethra 2. Oral-fecal 3. During birth v. Disease 1. Cause 80% of UTIs, sepsis, neonatal meningitis and traveler's diarrhea vi. Different strains 1. Enterotoxigenic E. coli (ETEC) a. Causes travelers diarrhea and diarrhea in infants b. Toxin is similar to cholera toxin 2. Enteroinvasive E. coli (EIEC) a. Disease closely resembling that caused by shigella 3. Enteropathogenic E. coli (EPEC) a. Diarrheal outbreaks in hospital nurseries and in bottle-fed infants 4. Enterohemorrhagic E. coli (EHEC) a. Strain # O157:H7 b. Consumption of undercooked hamburgers c. Bloody diarrhea (dysentery - blood in stool) d. Toxin depends on lysogenic conversion by bacteriophage e. Complication: i. Hemolytic uremic syndrome (hemolysis in tiny blood vessels resulting in anemia and renal failure) 2. Salmonella typhi i. Produces H2S gas (few organisms can produce this gas, so easily identified by this gas) ii. Killed by acid iii. More than 2,500 types based on antigens (Somatic-O, Flagellar-H, Capsular-K) iv. Habitat/Transmission 1. Human colon 2. Eggs/poultry 3. Fecal-oral spread 4. Flies v. Disease 1. Typhoid fever 3. Shigella species (S. dysteneriae, S. flexneri, S. boydii, S. sonnei) i. Habitat/transmission 1. Human colon 2. Fecal-oral transmission ii. Disease 1. Shigellosis, bacillary dysentery 2. Enterocolitis (dysentary) (inflammation of small intestine + colon) 3. Shiga toxin (stops protein synthesis in host cells) 4. Vibrio cholera i. Habitat/transmission 1. Human colon 2. Fecal-oral transmission (contaminated water or raw/undercooked seafood) ii. Disease 1. Cholera a. Cholera toxin which activates adenylate cycle i. Adenylate cyclase is the enzyme that converts ATP to cAMP (increases the cAMP which causes extra Cl and Na in the cell which causes more water to follow) b. Diarrhea called rice water stool because the poop is cloudy and has the consistency of rice water 5. Vibrio parahemolyticus i. Comma shaped ii. Found in warm sea water iii. Acquired by eating contaminated raw seafood iv. Outbreaks occur on cruise shops v. Diarrhea is toxin mediated 6. Campylobacter jejuni (Kampylos-curved) i. Motile w/ polar flagella ii. Responsible for 5-14% of worldwide diarrhea - MOST COMMON CAUSE OF GASTROENTERITIS in the US iii. Hosts: birds and ducks iv. Grows well in 42 degrees C v. Adhesins, cytotoxin and endotoxin vi. Disease: 1. Enterocolitis 2. Guillain-Barre syndrome (rare) a. Acute inflammatory demyelination polyneuropathy b. Can cause paralysis from the bacteria attacking myelin sheath (destroy nerves) 7. Klebsiella pneumoniae i. Facultative anaerobe ii. Large thick polysaccharide capsule iii. Habitat/transmission 1. Human enteric tract and upper respiratory tract 2. Aspiration from upper respiratory tract and by inhalation of respiratory droplets 3. Urinary tract by ascending spread of fecal flora iv. Diseases 1. Pneumonia, UTI, meningitis and wound infection 2. Thick bloody septum (current jelly), tissue destruction 8. Helicobacter pylori i. Produces urease enzyme(metabolizes urea to ammonia to stay alive in the stomach) ii. Habitat/Transmission  1. Human stomach 2. Fecal-oral transmission iii. Disease 1. Gastritis 2. Peptic ulcer disease 3. Gastric carcinoma 9. Enterobacter aerogenes and Enterobacter cloacae i. Diseases: UTI and respiratory infection 10. Serratia marcescens i. Facultative anaerobe/motile/produces red pigment at room temperature ii. Habitat 1. Respiratory and urinary tracts of hospitalized adults and in gastrointestinal system of children iii. Diseases 1. Nosocomial pneumonia 2. UTI and sepsis 11. Proteus species (P. vulgaris, P. mirabilis) i. Facultative anaerobe ii. Highly motile/non-lactose fermenter iii. Produces urease enzyme - manipulates urinary pH to produce ammonia 1. Cranberry juice is recommended to prevent UTI because it keeps urine acidic iv. Habitat/transmission 1. Human colon 2. Environment (soil/water) 3. To urinary tract is by ascending spread of fecal flora v. Diseases: 1. UTI and sepsis 12. Pseudomonas aeruginosa ii. Pyocyanin (blue-green pigment) 1. Green pus (diagnostic of pseudomonas aeruginosa) iii. Present everywhere 1. environmental water sources (hospital humidifiers and respirators) 2. Skin, upper respiratory tract and colon iv. Diseases: 1. Opportunistic pathogen 2. Causes following infections: a. Important in burn and immunocompromised patients and cystic fibrosis patients b. UTI c. Respiratory tract infections d. Dermatitis e. Soft tissue infections f. Bacteremia g. Gastrointestinal infections 13. Haemophilus ducreyi i. STD ii. Painful, soft ulcer iii. Lymph nodes become enlarged Gram-negative bacilli/rods (RESPIRATORY) 1. Haemophilus influenzae (blood loving) i. Fastidious requires factors X and V  ii. 6 different strains (a to f) - type b causes 95% of invasive disease iii. Habitat/transmission 1. Upper respiratory tract 2. Respiratory droplet iv. Pathogens: 1. Haemophilus influenzae a. Second most common cause of community acquired pneumonia behind streptococcal pneumoniae 2. Haemophilus aegyptius 3. Haemophilus ducreyi (venereal disease) a. Venereal disease are sexually transmitted diseases v. Diseases: 1. Meningitis, Pneumonia, Otitis media, Sinusitis, Epiglottis, Tracheobronchitis vi. Vaccine 1. To prevent meningitis, should take the Hib vaccine (haemophilus influenzae type b) 2. Legionella i. Intracellular bacteria (can survive inside a living cell) ii. Present in water sources (air conditioners/cooling towers) iii. Disease: 1. Legionnaires disease a. Gradual onset flu-like symptoms b. People were in a hotel and the disease got into an air conditioner c. Can spread to gastrointestinal tract and the central nervous system 3. Bordetella pertussis i. "whooping cough" stages 1. Incubation period is when organism enters body and starts replicating but there are no symptoms 2. Catarrhal period is when patient will have running nose/watery eyes 3. Paroxysmal are the typical signs and symptoms of whooping cough 4. Convalescent - patient recovers and has no signs and symptoms but can still carry and transmit the disease ii. Vaccine 1. DaPT - has the antigen of pertussis Gram-negative bacilli/rods (ZOONOTIC - animal to human transmission) 1. Yersinia pestis i. Grows at 28 degrees Celsius ii. Plasmids w/ virulence genes iii. Resist killing by phagocytic cells iv. Habitat/Transmission 1. Reservoir is wild rodents (rats, prairie dogs and squirrels) 2. Flea bite (vector) v. Disease 1. Bubonic plague a. Bubos are enlarged lymph nodes** b. Used to be called black death in 14th century because there were 25 million deaths over a 5 year period c. Causes necrosis - that is why it is called black death 2. Pneumonic plague a. This is when bubonic plague is transmitted from human to humans 2. Pasteurella multocida i. Habitat/Transmission  1. Mouth of animals especially cats and dogs 2. Transmission by animal bite ii. Disease 1. Wound infection (cellulitis) 3. Brucella species (B. abortus - cattle, B. suis - swine, B. melitensis - goats/sheep, B. canis - dogs, foxes, coyotes) i. Habitat/transmission 1. Reservoir is domestic livestock (horses, cattle, sheep) 2. Via unpastuerized milk and cheese or direct contact w/ the infected animal (blood, urine, placenta) ii. Disease 1. Brucellosis (undulant fever or Bang's disease) a. Undulant means there are spikes in a fever b. NO ARTHROPOD VECTOR 4. Francisella tularensis i. Habitat/Transmission 1. Wild animals especially rabbits, deer and rodents 2. By tick (Dermacentor), aerosols, contact and ingestion 3. Disease a. Tularemia ("rabbit fever" or "tick fever") i. Ulcer at site of bite 5. Bartonella henselae i. Habitat/transmission 1. Oral flora of many cats 2. Cat scratches and bite ii. Disease 1. Cat scratch fever 2. Bacillary angiomatosis (nodules from proliferating blood vessels in skin) 3. Many of these complications happen in HIV patients because they are immunocompromised Gram positive bacilli (non-endospore forming rods) 1. Corynebacterium diphtheria (means club shape & skin/leather) i. Club-shaped arrange in V or L shape ii. Habitat/transmission 1. Human throat 2. Respiratory droplet iii. Disease causes diphtheria 1. Exotoxin inhibits protein synthesis by ADP 2. Pseudo membrane made of dead tissue/leukocyte in throat which cuts off oxygen supply 3. Also release cardiotoxin that affects heart x. DPT vaccine (combo of diphtheria, pertussis(whooping cough) and tetanus) 2. Listeria Monocytogenes i. Can grow at 4 degrees C (psychrophile) ii. Habitat/Transmission 1. Human GIT and female genital tract 2. Found in animals, plants and soil 3. Can cross the placenta 4. Ingestion of unpasteurized milk products (why you shouldn’t eat cold cuts) 5. Wide spread in water and vegetation iii. In newborn: 1. Can cause meningitis and sepsis in newborns and immunocompromised adults  2. Can cause stillbirth iv. Can cause gastroenteritis in adults Which of the following causative agents of bacterial meningitis is transmitted by contaminated food? Listeria monocytogenes 3. Lactobacillus Acidophilus i. This organism ferments sugar and produces acid so other pathogenic bacteria cannot survive ii. Habitat/Transmission 1. Ubiquitous in the environment 2. Oral cavity, vagina, acidic pH and intestinal tract iii. Used for probiotics in food industry 1. Live non pathogenic bacteria 4. Propionibacterium acnes i. Habitat/transmission 1. SKIN a. Resides in sebaceous glands and uses sebum as nutrient i. Makes propionic acid 2. Intestinal tract ii. Disease 1. Acne Vulgaris 5. Gardnerella vaginalis i. Fastidious (finicky eater) ii. Gram variable - can sometimes be gram positive or gram negative (so will need other tests) iii. Habitat/transmission 1. Human genitourinary tract 2. Sexual iv. Disease 1. Nonspecific bacterial vaginosis a. Clue cells i. Vaginal epithelial cells covered in G. vaginalis ii. You can diagnose a Gardnerella vaginalis bacteria if there are clue cells Gram-positive bacilli (endospore forming) 1. Bacillus anthracis i. Habitat/transmission 1. Soil 2. Contact w/ infected animal or inhalation of spores ii. Disease 1. Anthrax a. Has eschars (black necrotic tissue) 2. Cereus i. Habitat/transmission 1. Rice 2. Contaminated food ii. Disease 1. Food poisoning a. Exotoxin (enterotoxin) 3. Clostridium tetani i. Endospores 1. Can cause tetanus from the rusty nail allowing endospore in skin ii. Habitat/transmission 1. Soil 2. Traumatic breaks in the skin  iii. Disease 1. Tetanus or lock jaw a. Tetanospasmin (exotoxin) i. Blocks inhibitory neurons (blocks inhibitory neurotransmitters) 2. Neonatal can get tetanus if the umbilical cord is cut with dirty scissors 3. Vaccine contains inactivated tetanospasmin. 4. Clostridium botulinum i. Can get from soil or improperly preserved food (like honey or canned food) ii. Disease 1. Botulism (foodborne, intestinal, wound) a. Produces a neurotoxin i. Blocks release of AcH at neuromuscular junction ii. SPORES FOUND IN HONEY iii. Botox b. Floppy baby syndrome i. Muscles flaccid 5. Clostridium perfringens i. Soil/human colon or vagina ii. Disease 1. Gas gangrene (myonecrosis) a. Bacteria ferments sugar and creates gas b. Oxygen and more blood flow can kill the gangrene c. Lecithinacse d. Food poisoning 6. Clostridium sordelli i. Causes toxic shock syndrome 7. Clostridium difficile i. In human colon - fecal-oral ii. Disease 1. Pseudomembranous colitis a. Forms membrane in colon and has dead epithelium, inflammatory cells b. Cytotoxin that ruins mucosa in colon c. Want to treat w/ probiotics maybe even with poop Gram-negative cocci 1. Neisseria meningitidis i. Habitat/transmission 1. Human upper respiratory tract (5-15% of healthy people) 2. Respiratory droplet ii. Disease 1. Meningitis and meningococcemia a. Enters bloodstream 2. Meningitis epidemics in dormitories a. Meningococcal vaccine because can cause epidemic in dorms viii. 2. Neisseria gonorrhoeae i. Habitat/transmission 1. Human genital tract 2. Sexual contact 3. Neonates during birth ii. Disease 1. Gonorrhea (50-80% women no symptoms) 2. Pelvic inflammatory disease (25% women) 3. Ectopic pregnancy (ektos-outside, topos - place) and sterility a. Egg implants in fallopian tube - not uterus 4. Ophthalmia neonatorum is an infection caused by gonorrhea Gram-positive cocci 1. Staphylococcus Most frequent genus causing wound infection Drug resistance: ▪ Methicillin resistant Staph aureus (MRSA) and vancomycin resistant (staphylococci (VRSA) presents a serious problem in medicine today ▪ Aureus that are resistant to virtually all useful antibiotics ▪ These strains are currently a significant cause of nosocomial infections (healthcare associated infection) ▪ Linezoild could help but cost 1-2k Staphylococcus Aureus (pathogenic strain) ▪ Halophiles ▪ ONLY STAPHYLOCOCCI THAT IS COAGULASE POSITIVE ▪ Resistant to environmental stress ▪ Habitat and transmission Nose and skin, hand Opportunistic pathogen, but is normal microbiota ▪ Diseases caused: Folliculitis - inflammation of hair follicles Furuncle Carbuncle Impetigo - pus forming infection, superficial on the face Toxic Shock Syndrome - tampons in vagina can allow S.A. to grow and then subsequently releases an endotoxin and is absorbed in blood stream of the body Acute Endocarditis - Diseases can be categorized as acute (rapid onset), subacute (gradual in onset) and chronic (more than 3 months late in onset) Food poisoning (toxin) When S.A release an entrotoxin, it will enter gastrointestinal tract Osteomyelitis Inflammation of bone and bone marrow Scalded skin syndrome - S.A. release exfoliatin, which is an endotoxin that dissolution of epidermal  (desmosomes attach cells together) Anaerobic bacteria will start to grow Wound infection S.A. key player in wound infection Present everywhere Staphylococcus Epidermis ▪ Habitat & Transmission Normal flora of the skin and mucous membrane Person to person ▪ Diseases Subacute bacterial endocarditis on prosthetic heart valves The glycocalyx can adhere to basilar surfaces UTI Staphylococcus Saprophyticus ▪ Coagulase negative ▪ Resistant to novobiocin (an antibiotic) You can tell the difference between saprophyticus and epidermis because saprophyticus will be able to grow in the presence of antibiotics (novobiocin) ▪ Disease UTI Cystitis Bacteriuria, hematuria, pyuria Organism is the causative agent in 10-20% of UTI infections in sexually active young women The number 1 UTI causes bacteria is E.coli and then 2 proteus and then 3 saprophyticus 2. Streptococcus Characteristics ▪ Catalase negative ▪ Produce hemolysin, an endotoxin that can lead to hemolysis Alpha hemolysis Incomplete hemolysis olive green to brown E.g. S. pneumoniae and Viridans (S.mutans, S. Mitis and S. Salivarius) Beta-hemolysis Complete hemolysis E.g. strep pyogenes (strep throat) and strep agalactiae (resides in vagina, meningitis in newborns) Gamma-hemolysis No hemolysis Two strep that produce, couldn't hear names * ▪ Rebecca Lancefield divides streptococci into serotype groups based on the bacteria's antigens (also known as Lancefield antigen) Group A (streptococcus pyogenes) Still sensitive to penicillin Habitat and transmission Human throat and skin Respiratory droplets Strep throat Swollen tonsils Common during fall/winter because children are confined inside and it is highly spreadable (community inquired infection) Necrotizing fascitis (flesh eating disease) Necrosis of muscle fascia  Bacteria can digest tissue Scarlet fever (pyrogenic erythrogenic toxin) Strawberry tongue characteristic Can occur if it strep throat isn't treated quickly(complication of strep throat) Pyogenes produces exotoxin that creates red tongue and red rash in armpits Rheumatic fever Antibodies made after pyogenes cross react with heart valves and cause this fever Impetigo (AKA pyoderma) Superficial Children living in unhygienic conditions Erysipelas Erythos=red, pella=skin Cellulitis (superficial skin infection) - seen in elderly people Cellulitis Acute Glomerulonephritis Immune response - antibodies cross react and cause kidney failure Otitis media Middle urine infection Sinusitis Inflammation of sinus Toxic Shock Syndrome Pyogenes can cause TSS, but more common in staphylo. aureus Group B (strep. Agalactiae) Beta hemolytic Catalase negative Habitat/transmission Lives in human vagina During birth Disease Neonatal meningitis 1. Birth-30 days it will develop Septicemia 1. Can be fatal 2. Deliver baby in antibiotics Group D (enterococcus faecalis, E. faecium) Habitat/Transmission Resides in human colon Urethra/female genital tract Are part of the normal intestinal flora Disease - opportunistic UTI Biliary tract infection Endocarditis is rare but life-threatening Streptococcus pneumoniae (non-Lancefield) 85 serotypes (85 different types) based on antigenicity of polysaccharide capsule Habitat/transmission Human upper respiratory tract Respiratory droplet Disease Pneumococcal pneumonia (60%) - lower respiratory infection and meningitis in adults (enters blood stream and effects meninges) Otitis media and sinusitis in children  1. Pneumococcal vaccine Streptococcus Viridans (non-Lancefield) Characteristics Mutans, S. mitis, S. sanguis, and S salivarius Habitat and transmission Reside in human oropharynx (not highly pathogenic) Bloodstream during dental procedure Disease Sub-acute endocarditis 1. Could get to heart Dental caries (S. mutans) 1. Glycocalyx can adhere to enamel on teeth - ferment on teeth and use sugar to produce acid that erode enamel Special Groups: Acid-fast rods: 1. Mycobacterium tuberculosis i. Resistant to drying, disinfectants and strong acids ii. Gram-positive but they have mycolic acid, so need acid fast stain iii. Cause chronic infection(survive long periods of time) because of the presence of mycolic acid in cell wall iv. Killed by pasteurization v. Very slow growing - need 24 hours to see growth vi. Not always infectious/can be transmitted vii. Habitat/Transmission 1. Human lungs 2. Via respiratory droplet produced by coughing viii. Disease 1. Tuberculosis a. Chronic disease b. Granuloma forms (giant multinucleated cells, lymphocytes) causes miliary tuberculosis c. Caseous necrosis (lung tissue dying) 2. Vaccine a. BCG (bacille Calmette-Guerin) vaccine 3. MDR (multi-drug resistant) and XDR (extensively drug resistant) strains are very deadly ix. Screening 1. Tuberculin test a. Small amount of protein is injected intradermally and we wait 24 hours - look for swelling and if swelling is more than 10 mm, test is positive… it means patient has been exposed because of reaction from antigen or it can be from the vaccine… x-ray is the next step to see if they actually have tuberculosis or if it is from vaccine 2. Mycobacterium leprae i. Optimal growth at cooler temp of 30 degrees celcius ii. Affect skin, nose and peripheral nerves iii. Habitat/transmission 1. Humans and nine band armadillos (reservoir) 2. Nasal secretion (dir4ect contact) iv. Disease 1. Leprosy (Hansen disease) a. 2 types  i. Tuberculoid leprosy A. Strong cell-mediated immune response B. Tries to confine organisms ii. Lepromatous leprosy A. Weak cell-mediated immune response, but strong antibody response B. Progressive loss of facial features, digits and body structures 3. Mycobacterium avium-intracellulare complex i. Spread from birds and is tuberculosis-like that affects AIDS patients heavily Spirochetes 1. Treponema pallidum i. Corkscrew shape ii. Habitat/Transmission 1. Human genital tract 2. By sexual contact and from mother to fetus across placenta (during any stage) iii. Disease 1. Syphilis 4 stages of syphilis (STD) 1. Primary a. Characterized by chancre/chancroid or ulcer on genitalia b. May progress to infect fetus and cause congenital syphilis 2. Secondary a. Body-wide rash b. May progress to infect fetus and cause congenital syphilis 3. Latent a. May last for years b. May never progress 4. Tertiary (non infectious because of immune response) a. May progress to gummas(painful rubbery lesions), neurosyphilis, cardiovascular syphilis Gummas - necrosis in cardio and neurological systems 2 bacteria that can cross placenta - syphilis and listeria monogeneses *** iv. Human pathogens 1. Pallidum causes syphilis 2. T. pertenue causes yaws a. Tropical infection of the skin, bones and joints b. In warm, humid environments 3. T. carateum causes pinta a. Skin infection presents a raised papule, then flat reddened areas, fluish coloration and then loos of pigmentation b. Children living in poor hygienic conditions 2. Treponema pallidum i. Causes lyme disease ii. Mice and deer are reservoir iii. Deer Ticks (lxodes scapularis) are the VECTOR iv. MOST COMMON TICK-BORNE DISEASE IN THE US 1. Stages Stage 1: Starts with bullseye rash Stage 2: nervous system is affected Meningitis, encephalitis, and peripheral nerve neuropathy Electrical conduction is impaired - patients need pacemaker  Stage 3: Swelling and tenderness of large joints Chronic nervous system impairment Obligate Intracellular Parasite 1. Chlamydia trachomatis i. Infectious form is called Elementary body ii. Noninfectious form is called Reticulate body iii. #1 STD in the US iv. Disease 1. Nongonococcal urethritis 2. Cervicitis 3. Inclusion conjunctivitis (ophthalmia neonatorum) 4. Lymphogranuloma venereum 5. Trachoma a. Infecting of the eye b. Can be transmitted via fomite c. Leading cause of non-traumatic blindness 6. Pneumonia in infants 2. Chlamydia pneumoniae i. Disease 1. Causes atypical pneumonia 3. Chlamydia psittaci i. Causes psittacosis (parrot fever) ii. Primarily the disease of birds 4. Rickettsia rickettsii i. Dogs and rodents are reservoir ii. Ticks (Dermacentor) - dog ticks iii. Replicate in the cytoplasm and nucleus of their host cell iv. Causes Rocky Mountain spotted fever 5. Rickettsia prowazekii i. Causes epidemic typhus ii. Transmitted via lice Cell Wall-less Bacteria 1. Mycoplasma pneumoniae i. No shape - pleomorphic ii. Lack of seasonality - can survive during any season iii. Causes atypical pneumonia (walking pneumonia) iv. Mild symptoms and body can usually self heal v. Penicillin and cephalosporin cannot treat because of the lack of cell-wall