BACTERIOLOGY Past Papers PDF

BACTERIOLOGY Early discoveries: LESSON 1: HISTORY OF MICROBIOLOGY 1. Robert hooke Personalities contributing in development of o Observed tissue plants, he used simple microbiology...

BACTERIOLOGY Early discoveries: LESSON 1: HISTORY OF MICROBIOLOGY 1. Robert hooke Personalities contributing in development of o Observed tissue plants, he used simple microbiology magnifying glass o Suggested all living things a re made up 1. LUCRETIUS (roman philosopher) & GIROLAMO from cell. FRACASTRO (physician) o Cell= little boxes o Believed invisible creatures were 2. Anton Van leeuwenhoek responsible for disease; any small insects o Not a scientist he is a haber dasher that 2. FRANCESCO STELLUTI uses lenses to examine cloth o Observed bees and weevils using a o “Animalcules” microscope in early 1600s o first to observe bacteria and protozoa During ancient civilization, they believe in THEORY OF 3. Louis Pasteur o French chemist SPONTANEOUS GENERATION o Father of microbiologist “Life arise from non-life” o Theory of Biogenesis “Life comes from life” o Microbes can be destroyed by heat People who supported the theory: o Experiment: One neck flask 1. Aristotle: readily observable that aphids arise o Hypothesized “germ theory of disease” from the dew which falls on plants, fleas from  Microorganisms are putrid matter, mice and … responsible for infectious 2. John Needham: disease o Microbes reappear because of spont. Gen. o Experiment: He boiled chicken broth, the next day the broth has microbes (bcoz walang takip) o Hypothesis: life re-emerged due to spontaneous generation o British clergy man  Spallanzani challenged needham’s theory o Microbes appear from needhams experiment came from air o Experiment: boil the broth but he sealed it; no microbes appear People who do not support the theory: GERM THEORY OF DISEASE 1. Francesco Redi o Experiment: He put meat on 3 diff. jars with 1. Oliver Wendel Holmes cover o Reiterate the importance of handwashing o Flask 1 (open)- maggots appear 2. Ignaz Semmelweis o Flask 2 (with gauze)- maggots o Noticed death rated higher in maternity appear on the net; maggots laying wards eggs on the top of the net 3. John Snow o Flask 3 (sealed)- no maggots o Good public hygiene o First to formally challenge S.G o One of the father of epidemiology o “maggots unable to grow on meat if meat o Traced the source of cholera outbreak in was covered with gauze” London o Believed that maggots were because of flies o Calculate the dosage of anethesia o “sicknes is caused by a bad care” 4. John Tyndall o Cowpox and Smallpox: pag nagkaroon ng o Bacteria existed in 2 forms: cowpox yung tao di na nagkakaroon ng a. Heat Stable form (endospore) smallpox due to immunity b. Heat Sensitive form (vegetative 8. Paul Ehrich form) o Dermatologist o need intermittent and prolonged heating to o Wanted to find out the magic bullet to cure destroy spores syphilis o Tyndallization: process of sterilizing liquid o Developed Sarlvarsan preparation 606 “ by heating salvation from syphilis” 5. Robert Koch o The agent that causes syphilis can be o Confirmed germ theory of disease eliminated throough arsening derivatives o Originate use of two o Chemotherapy approach o Developed pure culture techniques 9. Walter reese o Culture way he used o Suggested to Koch to used agar 1. Gelatin: nakakain ng bacteria, nalulusaw 10. Richard Petris 2. Agar (extract from seaweed): bacteria o Petri dish will stay; not being metabolized by 11. Christopher Gram bacteria o Staining method o He was able to see the causative agent of 12. Sabouraud tuberculosis; mycobacterium tuberculosis o Yeast and molds (Koch’s Bacillus) 13. Ivanoski o Koch’s postulate o Tobacco mosaic 14. Waksman o Tetracydine & streptomycin Discovery of antimicrobial 1. Dogmak o prontosil 2. Fleming o Discovered penicillin by accident 3. Salk and Savin o Polio virus vaccine o Problem: o Pwedeng asymptomatic yung  Ruska patient pero may bacteria parine o Electron microscope, 1938 o May bacteria tayo sa loob ng  Watson & crick katawan na healthy o DNA, 1953 6. Jospeh lister:  Jacob & Monod o Father of modern antisepsis o Protein synthesis, 1965 o Surgeon that applied germ theory to surgery o Used of carbolic acid o He believed louis Pasteur o Infection is best avoided by preventing bacteria from getting in the wound 7. Edward Jenner o Created first vaccine  LESSON 2: MORPHOLOGY  single celled  through budding Micro- small o Mold Bio- life  Multicellular  Reproduce by using pores Logus- study - Illness: Athletes foot, ringworm Microbiology- study of living microorganism including  Multicellular parasites viruses o Live in or on another organism and use it for nourishment - Broad discipline that includes pure sciences PARASITIC WORMS Pure: 1. Round 1. Bacteriology 2. Flat 2. Mycology 3. Tape 3. Immunology 4. Insects 4. Virology 5. Mosquitoes 5. Parasitology Applied: 4. BACTERIA - Single celled prokaryotic organism 1. Chemotheraphy - Reproduce by binary fission 2. Agricultural - Shape 3. Paleomicrobiology: study of ancient microbes o Cocci- round 4. Biotechnology o Bacilli- elongated o Spiral Bioremediation- used microbes to remove toxins - Ability to retain dyes Microbial World o Gram (+): violet (crystal violet) o Gram (-): red (safranin) 1. VIRUS - Ability to grow with or w/o air; aerobic or - Smallest known infectious agents anaerobic - Subcellular microorganisms - Not a cell; contain only nucleic acid and protein coat Classification of Microorganisms - Nucleic acid can be either DNA or RNA but never both  Taxonomy: science of organizing, classifying & - Must live inside the cell in order to grow naming living things - Illness: common cold, flu, heap, warts, AIDs, o Originated by CARL VON LUNNE measles o Placed into a classification system 2. PROTOZOANS  Arrangement of bacteria into - Singled celled eukaryotic organism larger than groups bacteria  By serotypes, antimicrobial - Found in soil and water resistance - Illness: malaria (caused by plasmodium), o Nomenclature is process of giving amoebic dysentery, trichomoniasis vaginitis naming ,following binomial: by 2 - The only infective intestinal parasite is names, genus and species. Histolytica o Identification- use practical schemes to - Could be amebae, flagellates, ciliates, and distinguish 1 from another; may criteria parasitic sporozoans. 1. DOMAIN 3. FUNGI a) Eubacteria - Eukaryotic with rigid cell wall Prokaryotic o Yeast  Most disease causing Cell wall is chemically Cell wall is simple True bacteria complex With peptidoglycan in cells DNA is single circular DNA is linear multiple b) Archaea chromosome copies “extremophiles” Odd bacteria that live in extremes Both have ribosomes environments Not associated with disease MORPHOLOGY OF BACTERIA Can be found under the ocean, volcanoes etc.  Size:.2 - 1 micrometer c) Eukarya Cocci Have nucleus and organelles (humans, Bacilli animal, plants)  Rod shape 2 domain is dedicated for bacteria and another living  Coccobasicllus: enither sphere or organisms are in Eukarya. elongated 2. KINGDOM Spiral a) prokaryotes  Can cause lepto 3. PHYLUM  Vibrio- comma; causes cholera a) Gracilicytes  Spirillum- rigid body; nasa labas flagella 4. CLASS  Spirochete- yung flagella nakaikot sakanya a) scotobacteria kaya flexible 5. ORDER a) eubacteria 6. FAMILY a) enterobacteriaceae 7. GENUS 8. SPECIES  Mnemonics: Dumb Kings Play Chess On Funny Green Squares Naming organism - italicized or underlined - Ex: Staphylococcus aureus (S. aureus); Staphylococcus aureus  Genus: Noun, always capitalized  Species: adjective, lowercase All cocci are gram positive except Veillonella, Megaspoera, Neisseria, moraxella, Branhamella Bacterial cell: - contains 70 ribosomes All bacilli are gram negative except  Glycocalyx Contains sticky protective coating Prokaryotes Eukaryotes Capsule: fixed Small;.2-1 micrometer Slime: loosely attached Big, 10-100 micrometer  Cell wall Nucleus is absent because Nucleus is present Gives shape; contains peptidoglycan for there is no nuclear mem. staining properties  Cell membrane  Capsule: glycocalyx that is firmly attached, sugar- Allow in and out substances coat; polysaccharide  Plasmids It evades phagocytosis Extra chromosal DNA  Flagella  Pili  Pili Hairlike projections  Endospore  Fimbriae- common pili, use for  Survival mechanism attachment  Bacillus and Clostridium  Sex Pili- for conjugation; when a acteria  Can regenerate wants to donate its copy of plasmids to  Plasmid another bacteria May antibiotic resistance genes  Flagella  May gene na pwede mag produce ng Propels bacteria antibiotics na kaya mag resist Cocci do not have this  Lopotricus: isang end lang may flagella  Amphitricus: magkabilang dulo merong flagella  Peritricus: buong katawan meron  Atricus: walang flagella Mycoplasma: bacteria na walang cell wall LESSON 2: MICROBIAL GROWTH REQUIREMENTS Requirements for growth 1. Physical a) Temp b) Ph ESSENTIAL STRUCTURES OF BACTERIA c) Osmotic Pressure  Cell wall 2. Chemical peptidoglycan a) Carbon Gram positive: inner cell membrane and outer b) Nitrogen, sulfur, phosphorus cell wall (2 layers) c) Trace elements Gram negative: inner cell membrane, outer d) Oxygen cell wall, outermost outer membrane (3 layers) e) Organic growth factors  Cell membrane Bilayer of phospholipids  Cytoplasm Location of nuclear materials  Nuclear Material Circular shape, almost like a flower NON-ESSENTIAL STRUCTURES OF BACTERIA PHYSICAL GROWTH Bacteria can be classified into Halophiles: A. TEMPERATURE: bacteria only grown within a - VIBRIO: example of halophilic bacteria; limited range of temperature nakukuha pag kumakain ng seafood Psychrophiles Psychro = cold Psychotrophs Extreme Halophiles - Can withstand - Cold  0-15 deg (obligate) 30% salt loving concentration Moderate - Types: psychorphiles Facultative halophiles - 2-5% salt  Psychotrophs  20-30 deg concentration  Moderate psychorphiles CHEMICAL GROWTH A. CARBON Mesophiles - affects Min: 25 deg - Structural backbone of living matter human - All organic compounds are made of carbon Max: 40 deg o Phototrophs: depends on light; Optimum: 35- archaeans 47 deg o Chemotrophs: depends on chemicals Thermophiles - love Min: 50 Chemoheterotrophs - If the carbon higher source is organic Max: 60 compound temp Hyperthermophiles - usually 80-121 deg; Chemoautotrophs - If the carbon archaeans pwede ma- source is carbon - love to be autoclave if dioxide in very walang Photoheterotrophs Light; If the carbon source hot temp pressure is organic compound Photoautotrophs Light; If the carbon source B. pH is carbon dioxide - Lowest recorder ph that can be associated woth bacteria is ph 1 (chemoautotrophic) - Bacteria can grow narrow ph range near B. NITROGEN, SULFUR, PHOSPHORUS neutrality between 6.5-7.5 ; most are - For protein and nucleic acid synthesis meosphiles - Nitrogen: 14% dry weight of bacteria - Very few bacteria grow below ph 4 - Sulfur: 4% dry weight of bacteria - Molds & yeast: 5 & 6 pH - K, Mg, Ca: co factors for enzymes being produced by bacteria C. OSMOTIC PRESSURE - Water for growth C. TRACE ELEMENTS  HYPERTONIC - Fe, Cu, Me, Zn o Madaming salts - Present in tap water o Mag-sshrink  HYPOTONIC o It will swell and then burst  D. OXYGEN - We can consider oxygen as a poison; they in their system that can neutralize the poisonous effect of oxygen - Singlet oxygen: can inactive catalase - Peroxidase and catalase: neutralizing enzyme for oxygen - Peroxidase: can convert to water but no oxygen - Anaerobes walang SOD E. ORGANIC GROWTH FACTOR Obligate aerobes - Strict - Amino acids - They need - Purines oxygen - Pyramidines Facultative Anaerobes - Part-time aerobe and anaerobes - Basically they are Generation time: required for a cell to divide most aerobes bacteria doubling time is 1-3 hrs, others 24 hrs or more. - Their energy can PHASES OF BACTERIAL GROWTH decrease in absence of A. LAG PHASE oxygen - Preparing to synthesize B. LOG PHASE/ EXPONENTIAL GROWTH Obligate Anaerobe - Strictly no - Period of growth; most sensitive; regenerate oxygen - When they are more active Aerotolerant anaerobe - Can tolerate C. STATIONARY PHASE/ EQUILIBRIUM oxygen - Microbial deaths - Basically they are - Deaths are balance with new bacteria arising D. DEATH PHASE/ LOG DECLINE anaerobes - Number of deaths exceed number of new Microaerophiles - Can tolerate little bacterial cells amount of oxygen DETERMINATION OF GROWTH - Can only tolerate (direct) 5-10% of oxygen - Onti lang ang 9. PLATE COUNTS Peroxidase and - Measures of viable cells catalase - Colonies should be 30-300 to be countable o POUR PLATE: mix yung agar at inoculate Capnophiles - Love carbon o SPREAD PLATE: solid na yung media tas dioxide ippour na lang yung inoculate - Ex: Lieseria  - Higher acid production higher bacteria 15. DRY WEIGHT 10. FILTRATION - For molds and fungus - At least 100 ml of water are passed through a - Filtered to remove extraneous materials and thin membrane filter whose pores are too small dried in a desiccator to allow bacteria to pass CELL METABOLISM - Sum of all chemical reactions - Energy balancing act MICROBIAL METABOLISM: transformation of energy; from eating ATP - Kind of fuel needs to run a cell - Energy storing nucleotide - Consists of adenine, ribose & 3 phosphate 11. MPN METHOD - For water bacteriology OXIDATION-REDUCTION REACTION - Statistical estimation technique since the REDOX: chemical reaction in which electrons are gained, greater the no. of bacteria in a sample, the lost or shared in chemical reaction; addition of electrons more dilution is needed to reduce intensity 12. DIRECT MICROSCOPIC COUNT OXIDATION: removal of electrons - For milk Sa pagmemetabolize klailangan ng electron carriers: - Placed within defined area on microscopic slide FADH and NADH WHAT IS NADH? - Special molecules that cells use to carry electrons METABOLIC REACTIONS 1. Anabolic: synthesize 2. Catabolic: breakdown  EXERGONIC: produce more energy than they can consume Breed count  ENDERGONIC: consume more energy than they Petroff-hauser count can produce Electronic cell counters Pag sobrang catabolic reactions= madaming waste Pag sobrang anabolic process= kulang ng supply or production (indirect) CARBOHYDRATE CATABOLISM 13. TURBIDITY - Use of spectrophotometer  Aerobic cellular Respiration - Higher turbidity, the greater number of bacteria o Results in complex breakdown of 14. METABOLIC ACTIVITY glucose - Higher no. of waster products, higher bacterial  Anaerobic respiration and fermentation growth o Partially breakdown glucose Cellular respiration: energy generating process - Para maraming ATP maproduce - Proton gradient: to pump protons from one side Aerobic Sub Pathways to the other; difference in potential energy; ATP A. Glycolysis to ADP B. Synthesis of pyruvate to acetyl coA - Oxygen ang product C. Krebs cycle D. ETC A. GLYCOLYSIS ANAEROBIC CELL RESPIRATION - Energy investing stage: nag iinvest ng ATP to breakdown 6 carbon - Energy conserving stage - Net ATP: 2 - Final Product: 2 molecules of pyruvic acid and NADH - Occurs in CYTOPLASM Alternative: 1. Pentose Phosphate Pathway - 5 carbon sugar - Net gain of 1 mol of ATP plus 12 NADH 2. ENTER DOUDOROFF - Final product are nitrate, sulfate, carbon dioxide - Podruce 2 mols of NADH & 1 mol of ATp - Not all electron transport chain is used so less - Pseudomonas, trisodium gumagamit and atp na naprodruce, 2 lang - Lactic acid fermentation and alcoholic fermentation B. Synthesis of Acetyl CoA GLYCOLYSIS: pwede sa anaerobic and aerobic C. Krebs Cycle - Occurs in CYTOPLASM in prokaryotes; MITOCHONDRIA if eukaryotes CELL GENETICS - 6 NADH 2 FADH - 3 NADH, 1 FADH, 1GD, 2 Carbon - Single circular chromosomes that are filled with genes (important genes) - Not enclosed in a nuclear membrane D. ETC - Haploid - In CELL MEMBRANE; CRISTAE OF MITOCHONDRIA if eukaryotes GENOME SIZE LYTIC PHAGE (virulent) - Iinject niya yung nucleic acid - 0.16 Mb between 10 Mb - Iinfect nung - Base pairs: adenine , guanine, cytosine, tyrosine virus yung - Nagkakasya dahil sa super coiling bacteria; Ibbreakdown ang bacterial PLASMID cells - Contains not so important tools - kukunin niya - Extrachromosomal DNA yung materials - They encode genes, producing of antibiotics na gusto niya (prostoson) parta makabuo ng kagaya niya Bacterial reproduction is through binary fission; - Mas maraming vertical gene transfer genes makukuha A. CONJUGATION TEMPERATE OF PHAGE - It will just - cell to cell transfer through sex pilus recombine (lysogenic) - huling tinatransfer ang sex pilus nucleic acid to the breakdown of bacterial cell to produce more phages - Didikit lang sa chromosome ng cell - Can also become virulent if stressed - Lalabas siya sa pagkakadikit sa bacteria and B. TRANSFORMATION makukuha yung - Take up freely floating DNA portion of - Dapat competent cells para maka take up ng bacterial DNA DNA - Konti lang - Ginugutom ang bacteria to become competent makukuha - Gram positive ang mas competent - Must be integrated to the recipient cells through recombination  GENERALIZE TRANSDUCTION: random C. TRANDSUCTION gene, bacteriophage chop us the host - Use of phages- nag iinfects ng bacteria chromosomes into small fragments - Natransfer yung dna from one bact to another   SPECIALIZED TRANSDUCTION: specific sites like appendix gene; konti lang ang pwede niyang and tonsil, general matransfer effects are produced.  Only in a certain area of the body Cross infection  When a patient suffering from a disease and new infection it set up from another host or external source LESSON 3: INFECTION AND IMMUNITY Infection: injurious contamination of body either by Nosocomial infection  Hospital acquire bacteria, viruses, fungi etc. infections  Localized: confined to one part of the body Subclinical infection  It is one where clinical effect are not  Generalized (systemic): spread throughout the apparent body  The infection is in the patients but there are Classification of infection no signs and Primary infection  Initial infection with symptoms that would organism in host tell you that the  First time that the patient is infected host will encounter a with the certain microbe, virus, or any microbe microbe is the primary infection ACUTE, SUBACUTE AND CHRONIC Reinfection  Subsequent infection  ACUTE by same organism in a o rapid onset usually by a relatively host (after recovery) rapid recovery  After recovery, the o Examples: Measles, mumps, same organism will influenza attack the host o These are acute diseases you would Superinfection  Infection by same recover from 1 to 2 weeks organism in a host  CHRONIC before recovery o Has a slow onset and last a long time. Secondary infection  When in a host whose o Examples: Tuberculosis, leprosy, resistance is lowered syphilis by preexisting o It will take a long time for a patient infectious disease, a to recover from these set of illness new organism may  SUBACUTE set up infection (diff o Diseases that come on more agent) suddenly than chronic diseases but Focal infection  It is the condition less suddenly than acute diseases. where due to o Somewhere in between acute and infection at localized chronic illness  o Example: Bacterial endocarditis diseases are mostly easily transmitted during this stage LATENT INFECTIONS  Specific signs and symptoms are  disease that may go from being symptomatic to present that identify asymptomatic and then back to being having illness symptomatic  remains inactive for a period of time and then Convalescent Period  time when the person becomes active again when it changes its mind recovers. Person may and produce symptoms again recover from the  Ex: syphilis illness but there may be permanent damage of tissues of 4 PERIODS IN THE COURSE OF AN INFECTIOUS DISEASE the affected area Incubation Period  that elapses between the arrival of the EPIDEMIOLOGIC TRIAD pathogen and the onset of symptoms  incubation period will depend on the nature of the microbe that arrived in the body/system. (short or long) Prodromal Period  time during which the patient starts to feel something is wrong but do not experience yet the actual symptoms of the disease  Signs and symptoms are present but not specific (nonspecific signs and symptoms)  Ex. Fever, feeling heavy  The period wherein you know something is wrong in your body but don’t know the cause. Period of Illness  The time when the person experiences the symptoms of the disease. Communicable  WHY INFECTION DOES NOT ALWAYS OCCUR  Part of cell wall of gram negative 1. Microbe land at an anatomical site where it is  Can cause shock, fever unable to multiply 2. Pathogen must attach to specific receptor Characteristics: 3. Antibacterial factors that destroy growth of - Proteins polysaccharide lipid complex heat microbes stable 4. Overall health status - Forms part of cell wall (don’t diffuse into 5. Person maybe immune medium) 6. Phagocytic WBC may destroy it before having an - Obtained only by cell lysis opportunity - They have no enzymatic action - Effect is non-specific action - Indigenous Microbiota: they live inside us that - No specific tissue affinity can both cause harm and prevent; Nagiging - Active only in large doses 5 to 25 mg virulent and bacteria if napunta sa ibang site - Weakly antigenic CHARACTERISTICS OF PATHOGEN - Neutralization by antibody infective - Cannot be toxoided 1. Able to enter the body - Produce in gram negative bacteria 2. Able to multiply 3. Cause damage o EXOTOXINS: 4. Capable to resist the hist defense  Excreted out  Produce mostly by gram positive  PATHOGENECITY: ability of microbial species to produce disease Characteristics: - Heat labile protein VIRULENCE - Diffuse readily into the surrounding medium - ability of microbial strains to produce disease - Highly potent, e.g. 3kg botulinum can kill all the - how fatal would be the disease inhabitants of the world - They are generally formed by Gr+ bacteria and VIRULENCE FACTORS also by some Gr- organisms like Shigella, V. (pathogenic ang bacteria if meron siya nito) cholerae, and E. coli A. ADHESION - Usually produced primarily by gram positive - Attachment of bacteria to body surfaces - Exotoxin is specifically neutralized antitoxin - ADHESINS AND LIGANS: - Can be separated from culture by filtration o describe the molecule on the surface of - Action is enzymatic and it has specific tissue the pathogen that is able to recognize affinity and bind to a particular receptor - Cannot cause pyrexia (high fever) in a host o binds to specific surface of cells - Can be toxoided o ADHESINS: sa bacteria o LIGANS: sa host EXOTOXINS TYPES B. INVASIVENESS - Ability to spread in a host tissue after Neurotoxin  most potent exotoxin produced by establishing infection Clostridium tetani - Invasive=generalized; if hindi invasive=localized (causative agent of C. TOXIGENICITY tetanus) and - Bacteria produce 2 types of toxins Clostridium o ENDOTOXINS  Inside botulinum  Tetanospasmin  o spastic protein synthesis paralysis killing mucosal  Botulinum epithelial cells and o flaccid PMN’s paralysis (polymorphonucleus)  affects brain  avirulent Enterotoxins  produced in the intestine VIRULENCE FACTORS (exoenzyme)  Toxin B produced by C. difficile damages 1. communicability- survival and distribution of the surface of the organism in a community; kung na-ttransfer siya sa colon leading to ibang tao pseudomembranous 2. coagulase- prevent phagocytosis by forming fibrin; colitis s. aureus.  Cause diarrhea and 3. fibrinolysin- promote of spread of infection; breaks sometimes vomiting down fibrin barriers in tissue 4. hyaluronidase- breaking down hyaluronic acid; Toxic shock syndrome  Produced by strains spreading factor. toxin (TSST) of S. aureus and S.  Hyaluronic acid: cement that hold tissues pyogenes which together primarily affect the 5. Hemolysins- cause destruction of RBCs integrity of capillary i. Alpha: can cause greenish hemolysis walls. ii. Beta: complete hemolysis Exfoliative Toxin  causing sloughing of iii. Gamma: do not cause lysis of RBC the epidermal layers 6. IgA proteases- split IgA (immunoglobulin) of the skin leading to 7. Collagenase- Breaks down collagen which is the SSSS (staphylococcal supportive protein found in tendons, cartilage and scalded skin bones enabling the pathogen to invade tissues syndrome) cause by 8. Lecithinase- produced by Clostridium perfringens Staphylococcus which breaks down phospholipids; Clostridium aureus or by some perfringens cause gas gangrene Streptococcus pyogenes  It is usually seen in Virulence factors: newborn babies (skin reddish and Capsule (for S. Pneumoniae and Klebsiella Pnuemoniae) sloughing). The  since it evades phagocytosis; yung slimey epidermal layer is allows bacteria to escape being engulf by removed in the phagocytes process. Surface antigens Leucocidin  destroy leukocytes, produced by  V Antigen of Salmonella Staphylococcus and  K antigen of E. coli Streptococcus Diphtheria toxin  produced by Corynebacterium which inhibits  HOST-DEFENSE MECHANISM 2. Ingestion of microbe by phagocyte Definition of terms: 3. Formation of phagosome 1. Resistance: Ability to ward up disease 4. Fusion of the phagosome with a lysosome to form a  Non specific: protect against all pathogens phagolysosome  Specific: protect against specific pathogens; 5. Digestion of ingested microbe by enzyme antibodies 2. Susceptibility: lack of resistance 6. Formation of residual body containing indigestible material 2 types host-defense mechanism 7. Discharge of waste materials.  Non specific:  Serve to protect the body from a variety of foreign substances or COMPLEMENT ACTIVATION pathogens  first and second line of defense Consequences of Complement Activation:  Specific: 1. Cytolysis: Due to the formation of a membrane attack  Are directed against a particular complex (MAC) which produces lesions in microbial foreign substance or pathogen that membranes. has entered the body  third line of defense  The bacterial cell will lies because of the lesions that be created by the MAC. 2. Inflammation: Complement components (C3a) trigger the release of histamine, which increases vascular permeability.  It will attract macrophages and neutrophils. 3. Opsonization: Complement components (C3b) bind to microbial surface and promote phagocytosis. Refer to the reviewer!!!!! INTERFERONS Antiviral proteins that interfere with viral multiplication. PHAGOCYTOSIS 3 types of Interferons o Interferon alpha: produced by B lymphocytes, monocytes, and macrophages o Interferon beta: fibroblasts and other virus infected cells. o Interferon gamma: activated by T lymphocytes and NK cells SPECIFIC HOST DEFENSE MECHANISM The immune system is the third line of defense against pathogens; it is a specific host defense mechanism. Two types of acquired immunity 1. ACTIVE ACQUIRED IMMUNITY 1. Chemotaxis and adherence of microbe to phagocyte (the adherence of the microbe to the phagocyte will  Natural active acquired immunity: that is depends on the virulence factor) acquired in response to the entry of a live  pathogen into the body (i.e., in response to an  IgA: Known as secretory antibodies because actual infection). It has long duration. they are found in breastmilk, respiratory  Artificial active acquired immunity: that is and intestinal mucin, saliva, tears, and acquired in response to vaccines. Its duration vaginal secretions protect these parts of the for many years; but must be reinforced by body from infectious agents. It exists in boosters. three for monomer, dimere, trimere. 10- 20% of the total serum immunoglobulin is 2. PASSIVE ACQUIRED IMMUNITY: compose of IgA; body secretions  Natural passive acquired immunity: that is  IgD: It is found on the surfaces of the B- acquired by a fetus when it receives maternal lymphocytes where it acts as a specific antibodies in utero or by an infant when it antigen receptor. receives maternal contained in colostrum. Its  IgE: Its activities involved in both the duration from 6 months- 1 year. resistance to parasites infections and  Artificial passive acquired immunity: that is hypersensitivity. It is found on the surfaces acquired when a person receives antibodies of basophils and muscles.; allergies contained in anti-sera or gamma globulin. Its duration from 2-3 weeks.; rabies MICROBIAL CONTROL Physical/Heat Two Types of Immunity 1. Moist Humoral Immunity:  Pasteurization - Antibodies and antigens produces by B-cells  Boiling - an antibody is a protein produced in response  Autoclaving to foreign substance (antigen) that will react  Tyndaliization specifically with that substance. The reaction between the antibody and the antigen will lead 2. Dry- by oxidation of bacteria/ natutuyo to destroy the antigen or the pathogen that  Hot air oven carry the antigen or inhibit it.  Incineration CMI (Cell Mediated Immunity): 3. Radiation- destruction of DNA - major player is T-cell (kills intracellular  Ionizing- xray, gamma microbes); nagpproduce ng immunoglobulins  Non ioizing- UV - pag asa loob na ng katawan yung pathogen Chemical- denaturation of proteins - Does not involved production of antibodies - Controls intracellular pathogens  Alcohols  Aldehyde Classes of Immunoglobulin  Phenols-  IgG: This is the greatest percentage of  Halogens- heavy metals; iodophore antibody molecules in the blood, these  Gases- ethylene oxide globulins combine to small antigen and  Antibiotics combine and neutralize toxins (antitoxins). Mechanical Long lived and crosses the placenta.; pag chronic pasyente  Filtration  IgM: is a pentamer (pinakamalaki), has 10 o Air- HEPA/ULTRA antigen binding sites, first antibodies o Liquid- membrane filter formed in the primary response to antigens.  Handwashing Does not cross the placenta. ANTIBACTERIAL AGENTS  Penicillin  Vancomycin Drugs to treat diseases or kill agents of disease It is  Bacitracin CHEMOTERAPHY; apply the drugs to infections that will  Cephalosporins- may beta lactam ring have selective toxicity. B. Inhibition of functions of cell membrane; nag reregulate ng in and out substances, mawawala yung pagiging semi-permeable ng membrane 2 categories of chemotherapeutic drugs therefore mag sswell or mag shrink pag lumabas 1. Antibiotics mga contents  polymyxin - directly produce by microorganism C. Inhibition of protein synthesis- - ex: penicillin produced by penicillium  Tetracycline (doxycycline)- 30s  Aminoglycosides (Streptomycin, etc 2. Synthetics lahat ng may mycin)- 30s  Chloramphenicol- binds to 50s - antimicrobial drugs synthesize in the lab  Macrolides (erythron)- 50s - anti fungal, bacterial, viral, parasitic  Clindamycin- 50s IDEAL ANTIMICROBIAL D. Inhibition of nucleic acid synthesis; stop DNA  High selective toxicity; low toxicity to the host replication high selective toxicity in pathogens  Rifamycin- stop transcription  Low propensity for development of resistance  Quinolones (may mga floxacin)- stop  Not induce hypersensitivities in the host dna rep  Rapid tissue distribution E. Inhibition of folic acid synthesis  Free of interactions with other drugs  Sulfonilamide (Bactrim)  Inexpensive  Trimethroprim ANTIBIOTICS DRUG RESISTANCE - Antibacterial Spectrum: scope that drug kills growth of 1. Intrinsic- no target site in bacteria microorganism 2. Acquired- resistance acquired by mutation is unusual  Narrow: acts only in one kind of bacteria  Broad: wide antimicrobial scope; pwede sa -because of mutation gram – and + -acquired by r-factor ANTIMICROBIAL ACTIVITY -nakukuha sa plasmids 1. Minimal Inhibitory Concentration (MIC) MECHANISM OF RESISTANCE TO ANTIBACTERIAL  Min amount of drug required to inhibit growth 1. Antibiotic Inactivation of bacteria in vitro; least amount of side effects 2. Altered uptake of antibiotics 2. Minimal bacterial concentration (MBC)  Increased efflux  Min amount of drug acquired to kill bacteria in  Decreased permeability vitro 3. Structurally modified antibiotic 4. Development of altered metabolic pathway MECHANISMS OF ANTIMICROBIAL AGENTS AVOID THIS RESISTANCE A. Inhibition of cell wall synthesis: di na - avoid unnecessary use of antibiotics makakabuo ng peptidoglycan, walang cell wall  Amoxicilin - full dosage; bacteria is able to mutate pag hindi complete ang pag inom - wag gumamit ng topical antibiotics