Basic Microbiology

1. BASIC MICROBIOLOGY http://crisbertcualteros.page.tl

3. Actinomyces israelii

4. Bacteria Not Seen by Gram staining Giemsa or other tissue stain Intracellular, Very small Rickettsiae Inclusion bodies in cytoplasm Intracellular, very small Chlamydiae None No cell wall M. pneumoniae Darkfield micro/ Fluorescent micro Too thin to see Spirochetes Acid-fast stain High lipid in cell wall Mycobacteria Alternative Reason Name

10. TYPICAL BACTERIAL CELL

11. BACTERIAL STRUCTURE Adherence to surfaces Polysaccharide Glycocalyx vs. phagocytosis Polysaccharide Capsule Division septa Invagination of c.m. Mesosome Hydrolytic enzymes (phosphatases, B-lactamases, etc) Space between c.m. and o.m. Periplasm Osmotic barrier Oxidative and transport enzymes Lipid bilayer Cyto. membrane Endotoxin O antigen Lipid A Somatic O polysaccharide Outer membrane (porin, LPS) Rigid support Protection vs. osmotic pressure peptidoglycan Cell wall 1 , 2 , 3 Function Chem Comp Structure

12. BACTERIAL STRUCTURE Motility Protein (flagellin): basal body, hook, filament Flagellum Motility of spirochetes Axial filaments Common: attach to cell surface Sex: conjugation Glycoprotein (pilin) Pilus/fimbriae Storage of food and energy Glycoprotein, lipids, polyphosphates Granule Resistance to drying, heat, chemicals, UVL Keratin-like coat, dipicolinic acid Endospore Genes for antibiotic R, toxins DNA Plasmid Genetic material DNA Nucleoid Function Chem Comp Structure

28. Bacterial Growth Curve # viable cells time a b c d a- Lag phase b- Logarithmic phase c- stationary phase d- decline phase

33. STERILIZATION AND DISINFECTION

42. Antimicrobial Agents Drugs Mechanism of Action Penicillins, cephalosporins, imipenem, aztreonam, bacitracin, vancomycin, cycloserine Inhibition of cell wall synthesis Chloramphenicol, erythromycin, clindamycin Aminoglycosides, tetracyclines Inhibition of Protein synthesis Bind to 50S ribosomal subunit Binds to 30S ribosomal subunit -Sulfonamides, trimethoprim -quinolones, novobiocin, Metronidazole Rifampin Inhibition of nucleic acid synthesis Inhibition of nucleotide synthesis Inhibition of DNA synthesis Inhibition of mRNA synthesis

43. Antimicrobial Agents Drugs Mechanism of Action Alteration of Cell Membrane Polymyxin Antibacterial Isoniazid Others Inhibits mycolic acid synthesis Amphotericin B, nystatin, ketoconazole Antifungal

44. Figure 5-9 Mechanisms of bacterial gene transfer. (From Rosenthal KS, Tan J: Rapid reviews microbiology and immunology, St. Louis, 2002, Mosby.) Downloaded from: StudentConsult (on 24 September 2006 05:26 AM) © 2005 Elsevier Transformation -the transfer of naked or free DNA -requires competence of recipient cell

45. Figure 5-9 Mechanisms of bacterial gene transfer. (From Rosenthal KS, Tan J: Rapid reviews microbiology and immunology, St. Louis, 2002, Mosby.) Downloaded from: StudentConsult (on 24 September 2006 05:26 AM) © 2005 Elsevier Transduction - the transfer mediated by a bacteriophage

46. Figure 5-9 Mechanisms of bacterial gene transfer. (From Rosenthal KS, Tan J: Rapid reviews microbiology and immunology, St. Louis, 2002, Mosby.) Downloaded from: StudentConsult (on 24 September 2006 05:26 AM) © 2005 Elsevier Conjugation -the transfer of DNA thru a cell-to-cell contact -usually involves the sex pilus

80. GRAM (+) COCCI CATALASE TEST STAPHYLOCOCCUS STREPTOCOCCUS COAGULASE MANNITOL SALT AGAR S. AUREUS Novobiocin S S. EPIDERMIDIS S. SAPROPHYTICUS NOVOBIOCIN S. EPIDERMIDIS Sensitive S. SAPROPHYTICUS Resistant (+) (-)

81. GRAM (+) COCCI CATALASE TEST STAPHYLOCOCCUS STREPTOCOCCUS (+) (-) β -streptococcus S. pyogenes S. agalactiae Bacitracin S CAMP test + Hippurate HOH α -streptococcus S. pneumoniae Viridans Strep Optochin Bile solubility Quellung Animal patho S + + + R - - - γ -streptococcus Enterococcus S. bovis 6.5% NaCl penicillin Grow R No Grow S Gp A Gp B Gp D

83. PYR test – pyrrolidonyl arylamidase Normal flora Alpha hemolytic Dental caries Endocarditis Dextran Viridans strep No toxin Vaccine: capsular Alpha hemolytic Optochin (+) Bile solubility (+) Quellung rxn Meningitis (adult) Pneumonia (rusty sputum) Sinusitis Capsule, IgA protease S. pneumoniae (lancet-shaped) Flora colon, URT Alpha, beta or gamma hem., Growth 6.5% NaCl Penicillin R PYR test positive UTI, peritonitis, biliary tract infection, etc E. fecalis (Group D) Vaginal flora, URT Beta hemolytic Catalase (-) CAMP test Hippurate HOH Neonatal sepsis Neonatal meningitis S. agalactiae (Group B) (GBS) No penicillin resistance M12 strain – assoc with AGN Beta hemolytic Catalase (-) Bacitracin (+) PYR test positive ASO Sore throat Scarlet fever Pyoderma Erysipelas Rheumatic fever, AGN M protein Pyrogenic exotoxin S. pyogenes (Group A) (GABS) Impt. Feature Distinguishing characteristic Disease Virulence factor Organism

120. ELEK TEST – for toxigenicity Filter paper with antitoxin precipitin line Unknown (patient’s isolate) Positive control Negative control

132. MOTT – Mycobacterium other than tuberculosis Not transmitted person-to-person Acid-fast Opportunistic in immunocompromised Nonchromogen MAI Not transmitted person-to-person Acid-fast M. kansasii- pulmonary M. marinum-skin infection Photochromogens M. kansasii M. marinum Not transmitted person-to-person Acid-fast Cervical lymphadenitis in children Scotochromogens M. scrofulaceum Not transmitted person-to-person Acid-fasst Fast growers (<days) M. fortuitum Cannot grow in artificial media Acid-fast Tuberculoid leprosy Lepromatous leprosy M. leprae Lowenstein Jensen Middlebrook Serpentine growth No serodiagnosis Acid-fast Obligate aerobe Slow growing Nonpigmented Niacin(+) Catalase (68C) (–) Nitrate red’n + TB Cord factor sulfatides M. tuberculosis Impt. Feature Distinguishing characteristic Disease Impt. Virulence factor Organism

133. Forms of Leprosy Numerous lesions becoming nodular; loss of eyebrows, destruction of nasal septum Paresthesia Leonine facies Fewer lesions: macular, nerve enlargement, paresthesia No. of lesions and other symptoms Large no. of intra. organisms Nerve damage from overgrowth of bacteria in cells Loss of sensation burns and trauma Immune response (CMI killing infected cells) Granuloma formation nerve enlargement/ damage Loss of sensation burns and trauma Damage from High (foam cells totally filled) Low (paucibacillary) No. of org in tissue (-) (+) Lepromin skin test Weak CMI Strong CMI CMI LEPROMATOUS B O R D E R L I N E TUBERCULOID

135. MYCOBACTERIA AND CLOSE RELATIVES Rods Yes Yes, obligate Mycobacterium Rods, filaments Partial Yes Nocardia Rods, filaments No No, anaerobic Actinomyces Rods No Yes Corynebacterium Morphology Acid-fast? Aerobic growth? Genus

158. GRAM NEGATIVE BACILLI

164. Shiga-like toxin – inhibits protein synthesis by binding with 60S ribosomal subunit Persistent diarrhea Childhood diarrhea Fimbriae: ‘stacked brick-like’ biofilm; enterotoxin EAEC O157:H7 Bovine feces hamburger Sorbitol McConkey: NOT ferment SORBITOL Watery diarrhea Hemorrhagic colitis HUS Shiga-like toxin (Stx) (verotoxin) EHEC (VTEC) (STEC) 2 nd to Rotavirus Infantile diarrhea A/E; bundle-forming pili EPEC Watery diarrhea Dysentery (10%) Invasion and destruction of colonic epithelium EIEC Non-invasive Self-limited Toxin immunoassay Travellers’ diarrhea Childhood diarrhea LT – Adenyl cyclase ST- guanylate cyclase ETEC GASTROENTERITIDES/DIARRHEAS septicemia endotoxin E. coli 2 nd to GBS Neonatal sepsis and meningitis K1 capsule endotoxin E. coli Most common cause Lactose fermenter; TSI: A/A + gas; Pink colonies; Greenish metallic sheen UTI P-pili B-hemolysin E. coli Impt. Feature Distinguishing characteristic Disease Impt. Virulence factor Organism

166. Shiga toxin – subunit A – inhibits protein synthesis by binding to 60S ribosomal subunit subunit B – binding to receptor 3 activities: neurotoxic, cytotoxic, enterotoxic Infects animals Mimics appendicitis Non-lactose fermenter; TSI- K/A Cold enrichment Bloody diarrhea Enterotoxin Y. enterocolitica Not infect animals No bacteremia Lowest ID50: 100 Non-lactose fermenter; TSI- K/A; No H 2 S Bacillary dysentery: Painful passage (tenesmus) of bloody and mucoid stool Shiga toxin Invasiveness – ulcer at ileum and colon Shigella S. dysenteriae S. sonnei S. flexneri S. boydii Impt. Feature Distinguishing characteristic Disease Impt. Virulence factor Organism

167. Two children were bragging about their intelligence. &quot; When I was eight months old, I could walk,” said one. You call that intelligent?” responded the second child. “When I was that old, I let them carry me.

170. X factor only ‘ school of red fish’ Chancroid (soft chancre) Painful genital ulcer Bubo H. ducreyi Chocolate agar Levinthal med X and V factors Satellite phen Pneumonia bronchitis Meningitis Acute epiglottitis Otitis media Capsule (PRP) -type b Endotoxin IgA protease H. influenzae Impt. Feature Distinguishing characteristic Disease Impt. Virulence factor Organism No bacteremia Vaccines: killed org toxoid lymphocytosis Bordet Gengou med; Regan-Lowe med Pertussis, catarrhal paroxysmal (whooping cough) convalescence Capsule Toxin – ADP ribosylation B. pertussis

171. Zoonotic (domestic livestock) Transmitted by fleas Brucella agar Serologic confirmation Undulant fever Acute septicemia Facultative Intracellular parasite Brucella B. abortus B. suis B. melitensis Air conditioning; cooling towers; excavations No human-to-human transmission Dieterle stain, CYE med Opportunistic Immunocomp Legionaire’s dis. (atypical pneumonia) Pontiac fever Facultative intracellular L. pneumophila flea Bubonic plague Septicemic plague Pneumonic plague V and W Ag coagulase Y. pestis Water aerosols, raw vegetables, flowers Resistant to chem. agents, antibiotics; Oxidase + NONFERMENTING Bluish green pigment-pyocyanin Grape-like odor Obligate aerobe Nosocomial infection Burns, Immunocompromised (eg.,cystic fibrosis), ‘ hot tub folliculitis’ Echtyma gangrenosum Exotoxin - (target: liver); Capsule/slime layer P. aeruginosa Impt. Feature Distinguishing characteristic Disease Impt. Virulence factor Organism

186. Characteristics of Most Common Types of Vaginitis and Vaginosis 5-6 Above 4.5 Below 4 pH (normal = 3.8-4.2) Tender, red Pink Dry, red Appearance of vaginal mucosa Copious Copious Varies Amount of discharge Frothy Thin. frothy Curdy Consistency of discharge Greenish-yellow Grayish white White Color of discharge Foul Fishy Yeasty or none Odor Protozoa T. vaginalis Bacterium G. vaginalis Fungus C. albicans Agent Trichomoniasis Bacterial Vaginososis Candidiasis

199. A male crab met a female crab and asked her to marry him. She noticed that he was walking straight instead of sideways. Wow, s he thought , this crab is really special. I can’t let him get away. So they got married immediately. The next day she noticed her new husband walking sideways like all the other crabs, and got upset. “What happened?” she asked. “You used to walk straight before we were married. “ Oh, honey,” he replied. “I can’t drink that much everyday.”

202. CHLAMYDIA: Developmental Cycle

229. Gastritis Peptic and duodenal ulcer Gastric CA C. jejuni – gastro C. fetus - septicemia V. cholerae- cholera V. Parahemolyticus - Diarrhea (seafds) Disease Skirrow’s med Butzler’s med Skirrow’s med Butzler’s med TCBS Medium (+) (-) (-) Urease (-) (-) (+) Alk. pH thermophilic microaerophilic Oxidase test flagellum Gram stain (-) (+) 42 C (-) (+) (+) (-) (+) (+) (+) Single polar Single polar Single polar Gram (-) curved, S, U-shaped rod Gram (-) ‘gull-wing’ bacillus Gram (-) curved bacillus Helicobacter Campylobacter Vibrio

231. Important Bacterial Exotoxins: Inactivates EF-2 by ADP-ribosylation P. aeruginosa Activates adenylclase by ADP-ribosylation B. pertussis Activates adenyl cyclase V. cholerae Shiga-toxin – binds to 60S ribosomal subunit Shiga-like toxin S. dysenteriae Other Shigella spp ETEC – activates adenyl cyclase by ADP-ribos EHEC – shiga-like toxin E. coli Pyrogenic exotoxin – a superantigen S. pyogenes TSST – a superantigen S. aureus 3 toxins; one is an adenyl cyclase B. anthracis Alpha toxin (lecithinase)- damages membrane Enterotoxin - a superantigen C. perfringens Exotoxin B is cytotoxic to enterocytes C. difficile Blocks release of acetylcholine C. botulinum Block release of inhibitory transmitter Glycine C. tetani Inactivates EF-2 by ADP-ribosylation C. diphtheriae

234. REMEMBER! (most important encapsulated org) S ome K illers H ave P retty N ice C apsule S treptococcus pneumoniae K lebsiella pneumoniae H aemophilus influenzae P seudomonas aeruginosa N eisseria meningitidis C ryptococcus neofromans

235. cAMP (Toxins) C – cholera A – anthrax Σ – E. coli LT P - Pertussis

236. “ Do you think I’ll live another 50 years, Doc?” asked a patient. “ How old are you now?” “ Forty.” “ Do you drink, gamble or chase women?” “ No,” the man answered. “I don’t drink, I never gamble, and I detest women. In fact I don’t have any vices at all.” “ Why then,” the doctor retorted, “do you want to live another 50 years?”

237. IMMUNOLOGY