Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Bio 130 unit 2
| Question | Answer |
|---|---|
| Physical req for bacteria growth | temp pH Osmotic pressure |
| five types of temp growth | psychrophile psychrotroph mesophile thermophile hyperthermophiles |
| psychrophile | -5 to 15 |
| psychrotroph | 20 to 30 |
| mesophile | 25 to 45 |
| thermophile | 45 to 70 |
| hyperthermophiles | 70 to 110 |
| Three types of pH | neautrophiles acidophiles alkalophiles |
| neutrophiles | 5-8 best at 6.5-7.5 |
| acidophiles | below 5.5 molds and yeasts |
| alkalophiles | above 8.5 |
| extreme or obligate halophiles req | high osmotic pressure |
| facultative halophiles tolerate | high osmotic pressure |
| Chemical req | carbon: energy nitrogen: amino acids and proteins sulfure: decompose proteins, biotin, thiamine phosphorus: DNA, RNA< ATP trace elements: iron |
| microaerophiles | require low oxygen concentration in order to grow |
| aerotolerant anaerobes | can grow with either with or without oxygen |
| culture media types: | culture medium: nutrients prepared for microbial growth sterile: microbial less environment inoculum: introduction of microbes into medium culture: microbes growing in/on culture medium |
| agar make up | polysaccharide note metabolized by microbes liq at 100c solid 40c |
| chemically defined media | growth of chemoautotrophs and photoautotrophs; microbiological assays |
| complex media | growth of most chemoheterotrophic organisms |
| reducing media | growth of obligate anaerobes, uses thioglycolate or oxyrase |
| selective media | suppression of unwanted microbes; encouraging desired microbes |
| differential media | differentiation of colonies of desired microbes from others blood agar |
| enrichment media | similar to selective media but designed to increase number of desired microbes to detectable levels |
| capnophiles | thrive in high concentrations of CO2 |
| Biosafety levels | BSL- 1 no special precautions 2- lab coat, gloves, eye protection 3- biosafety cabinets to prevent airborne transmission 4- sealed, negative pressure, air is filtered twice |
| types of selective media | thayer-martin agar macconkey agar msa agar |
| how to preserve bacterial cultures | deep-freezing -50 to -95 deg C lyophilization (freeze-drying): frozen (-54 to -72) and dehydrated in a vacuum |
| types of reproduction in prokaryotes | binary fission budding conidiospores (actinomycetes) fragmentation of filaments |
| Phases of bacterial growth | Lag, log, stationary, death |
| Lag phase | intense activity preparing for population growth but no increase in population |
| Log phase | logarithmic or exponential, increase in population |
| stationary phase | period of equilibrium microbial deaths balance production of new cells |
| death phase | population is decreasing at a logarithmic rate |
| methods of microbial growth | direct measurement: plate counts, serial dilutions, pour and spread plates, filtration. Estimating bacterial numbers: turbidity, metabolic activity, dry weight |
| serial dilutions method | taking 1ml from each broth and keep adding it to a new one over and over thinning out the colones |
| direct microscopic count | number of cell counted/ volume of area counted |
| Turbidity | using a light sensitive detector and a light source to test the number of bacteria inside |
| Sepsis | microbial contamination |
| asepsis | in the absence of significant contamination. aseptic surgery tech., tech prevent microbial contamination of wounds |
| serilization | removing all microbial life |
| commercial sterilization | killing c. botulinum endospores |
| disinfection | removing pathogens |
| antisepsis: | removing pathogens from living tissue |
| Degerming | removing microbes from a limited area |
| sanitization | lowering microbial counts on eating utensils |
| biocide/germicide | killing microbes |
| bacteiostasis | inhibiting, not killing microbes |
| Microbial death rate is | exponential. at a constant rate |
| what are the factors of the effectiveness of treatment | number of microbes environment (organic matter, temp. biofilms) time of exposure microbial chara |
| How do microbial control agents work | alteration of membrane permeability damage to proteins: can damage by breaking hydrogen bonds an covalent bond damage to nucleic acids: DNA and RNA rep |
| What are the physical methods of microbial control with heat | thermal death point (TDP) Thermal death time TDT decimal reduction time |
| thermal death point | lowest temp at which all cells in a culture are killed in 10mins |
| thermal death time | time during which all cells in a culture are killed |
| Decimal reudction time | minutes to kill 90 of a population at a given temp |
| moist heat sterilization | denatures proteins autoclave: steam under pressure uses: laboratory glassware, other equipment and waste, surgical instruments and medical waste. culture media |
| pasteurization | reduces spoilage organism and pathogens 63 deg C for 30mins high: 72 C for 15 sec ultra 140 for <1sec thermoduric organisms survive uses: milk, yogurt |
| Dry heat sterilization | kills by oxidation: dry heat, flaming, incineration, hot-air sterilization |
| filtration | HEPA - removes microbes >0.3um membrane filtration removes >0.22um used for in cases of e.coli (water testing) |
| physical methods of microbial control | low temp: inhibits growth (refrig, deep-dreezing, lyophilization) high pressure: denatures protins desiccation: prevents mtabolism osmotic pressure: causes plasmolysis |
| radiation | ionization radiation (xrays, gamma rays, electron beams) inoizes water to release OH, damages NA Nonionizing radiation (UV,20nm) microwaves kill by heat |
| determination of effectiveness of disinfectants | concentration of disinfectant organic matter pH time |
| use-dilution test | metal rings dipped in test bacteria are dried. Dried cultures are placed in disinfectant for 10 mins at 20 deg C rings are transferred to culture media to determine whether bacteria survived treatment |
| Phenol and Phenolic | disrupt plasma membranes disinfectant used on wounds |
| Bisphenols | Hexachlorophene,triclosan disrupts plasma membranes |
| Biguanides | chlorohexidine disrupts plasma membrane. afected gram negative bacteria, not sporophyte |
| halogens | iodine: tinctures - in aqueous alcohol. Iodophores: in organic molecules. Alter protein synthesis and membranes Chlorine: Bleach: hypochlorous acid (HOCl). Chloramine: Chlorine + ammonia. Oxidizin agents |
| alcohols | ethanol, isopropanol. denatures proteins, dissolve lipids. Require water |
| Heavy metals | Ag, Hg, Cu Silver nitrate may be used to prevent gonorrheal ophthalmia neonatorum Silver sulfadiazine used as a topical cream on burns Copper sulfate is an algicide Oligodynamic action Denature proteins |
| chemical food preservatives | Organic acids Inhibit metabolism Sorbic acid, benzoic acid, and calcium propionate Control molds and bacteria in foods and cosmetics Nitrite prevents endospore germination Antibiotics Nisin and natamycin prevent spoilage of cheese |
| Aldehydes | Inactivate proteins by cross-linking with functional groups (–NH2, –OH, –COOH, –SH) Use: medical equipment Glutaraldehyde, formaldehyde, and ortho-phthalaldehyde |
| Gaseous Sterilants | Denature proteins Use: heat-sensitive material Ethylene oxide |
| Plasma | Free radicals destroy microbes Use: tubular instruments when gas is excited medical inst. and hollow tubes |
| Supercritical Fluids | CO2 with gaseous and liquid properties Use: medical implants |
| Peroxygens | Oxidizing agents Use: contaminated surfaces O3, H2O2, peracetic acid |
| types of antimicrobial drugs | chemotherapy: the use of drugs to treat a disease antimicrobial drugs: interfere with growth of microbes within host antibiotic: produced by a microbe that, in small amounts, inhibits another microbe selective toxicity: kill harmful microbes w/ dam hos |
| Salvarsan P Ehrilich | 1910 treatment for syphilis |
| fleming | penicillin |
| prontosil | against streptococcal injections in animals. FIrst sulfa drug, sulfonamide |
| Howard Florey and ernst chain | performed first clinical trials of penicillin |
| Bacteriostatic drugs | rely on host immunity to eliminate the pathogen after growth has been inhibited |
| bacteriocidal drugs | are useful in situations when host defenses cannot be relied upon to remove or destroy the pathogen |
| Major actions modes | inhibition of cell walls synthesis protein synthesis nucleic acid replication essential metabolite synthesis |
| cell synthesis inhibitors | Penicillin, cephalosporin Vancomycin Bacitracin |
| Natural penicillins | pen G requires injection pen V orally |
| types of semisynthetic penicillins | oxacillin: narrow spectrum, only gram-positives, but resistant to penicillinase ampicillin: extended spectrum many gram- negatives |
| types of Beta-lactam antibiotics | penicillin: cephalosporins: |
| Generations of cephalosporins | first: narrow spect. act against gram positive bacteria sec: extended spectrum includes gram-neg. bacteria thr: includes pseudomonads; injected for: oral |
| bacitracin | topical application against gram pos inhib cell wall synthesis |
| vancomycin | glycopeptide important last line against antibiotic-resistant S. aureus cell wall inhibit |
| antimycobacterial antibiotics used for... | Isoniazid. inhibits mycolic acid synthesis Ethambutol: inhibits incorporation of mycolic acid M. tuberculosis |
| inhibits protein synthesis | chloramphenicol aminoglycosides tetracyclines Macrolides Streptogramins oxazolidinones |
| Chloramphenicol | broad spectrum in: protein synthesis |
| aminoglycosides | streptomycin, neomycin, gentamicin board in: protein synthesis |
| tetracyclines | board. able to be used for the all of the prokaryotes interferes with tRNA attachment |
| Macrolides | gram-positives includes: erythromycin, azithromycin, clarithromycin in: protein synthesis |
| oxazolidinones | linezolid against penicillin-resistant G+ MRSA in: pro syn |
| injury to plasma membrane | Polymixn B Lipopeptides: Daptomycin |
| lipopeptides | structural changes in the membrane, followed by arrest of the synthesis of DNA, RNA, and protein MRSA injury to plasma membrane |
| Polymyxin B | Topical combined with bacitracin and neomycin in over-the-counter-preparation |
| Inhibitors of nucleic acid synthesis | Fluoroquilones:ciprofloxcin Rifamycins Metronidazole |
| Rifamycin | inhibits RNA synthesis antituberculosis |
| Quinolones and Fluoroquinolones | Nalidixic acid: urinary infections ciprofloxacin inhibits DNA gyrase urinary tract infections |
| inhibits metabolic pathways | Sulfonamides Trimethoprim |
| Sulfonamides (Sulfa drugs) | inhibit folic acid synthesis broad spectrum |
| What does Sulfonamides inhibit | para-aminobenzoic acid (PABA) which is required for bacterial metabolism. It mimics it and competitively inhibits the enzymes involved in its production |
| MIC stands for | minimal inhibitory concentration |
| MBC | Minimal bactericidal concentration |
| synergism | occurs when effect of two drugs together is greater than the effect of either alone |
| antagonism | occurs when the effect of two drugs together is less than the effect of either alone |
| antifungal drugs that inhibit ergosterol | polyenes: amphotericin B Azoles: Miconazole, triazole Allylamines: For zole-resistant infections |
| Antifungal drugs: inhibiting cell wall synthesis | echinocandins: inhibits synthesis of glucan. Cancidas is used against candida and pneumocystis |
| antifungal: nucleic acids | flucytosine: cytosine analog interfers with RNA synthesis Pentamidine isethionate: anti-pneumocystis; may bind DNA |
| antifungal drug inhibits microtubule formation | Griseofulvin |
| Antifungal drug with an unknown function | Tolnaftate |
| Antiviral drugs | Protease inhibitors: HIV Integrase inhibitors: HIV Entry inhibitors: Amantadine, influenze Fusion inhibitors: Zanamivir, influenza. blocks CCR5: HIV Interferons: prevent spread of viruses to new cells |
| imiquimod | promotes interferon production |
| antiprotozoan drugs | Chloroquine: inhibits DNA synthesis. Malaria Artemisinin: kills plasmodium sporozoites Metronidazole: interferes with anaerobic metabolism. Trichomonas and giardia |
| antihelminthic drugs | Niclosamide: Prevents ATP generation, tape worms Praziquantel: Alter membrane permeability, flatworms Mebendazole and albendazole interfere with nutrient absorption, intestinal roundworms ivermectin: Paralysis of helminths, intest worms Chloroquine |
| where is the resistance genes located | plasmids and transferred between bacteria |
| Therapeutic index | risk vs benefit |
Created by:
lilram