BIO test 3

• 60-135 degrees C
• denature proteins and destroy membranes
• methods: boiling, autoclaving (), pasteurization, and ultra high temperature sterilization

Kills veg. bacteria; and fungi, prpotozoa trophozoites, and most viruses. Length of boiling one time is critical. (not cysts, spores and some viruses)

uses steam under pressure. Boiling temp increases, increases pressure; can sterilize

liquids that we don’t want to change the consistency (milk, ice cream, apple cider, fruit juice) NOT sterilization and if are heat tolerant will survive. Time and heat can vary. Heat short time 60-73 degrees

140 degrees X 1 sex, rapid cool, stored at room temperature

• Higher temperature= 160- several thousands
• Used when moist heat methods don’t work
• Results in: burning of cells, cell damage and dehydration/incineration
• Need higher temperature for longer times than in moist heat (ULTIMATE TECHNIQUE)

refrigeration and freezing
• Decreases microbial metabolism, growth and reproduction
• At freezing liquid water is not available, refrigeration (happens very slowly)
• Psychrophils are exception

• Desiccant= something that can remove water
• Drying inhibits the growth of the microbes because of the removal of water; metabolism can’t take place

increase salt or sugar in foods, inhibits growth, cells lose H20

energy emitted from atomic activities and dispersed @ high velocity through matter or space

radiation ejects E- from atom, causing ion to form breaks of DNA or protein damage (leading to cell death)

excites atoms to higher energy state, but doesn’t cause ions to form→ when electrons excited → cause damage, make new covalent bonds (when they should not be doing it—weird covalent bonds) + alter the 3-D structure of proteins and NA’s.

messes up the DNA in skin cells, too many mutations= cancer (doesn’t penetrate well)

physical removal by a filter to remove particles/ microbes
• Filter pore size is important

Phenol and Phenolic compounds, Alcohols
Halogens, Oxidizing agents, Surfactants,Heavy Metals,
Aldehyde

o Intermediate disinfectant
o Denature proteins of organic matter
o Active for long time

o Intermediate disinfectant
o Ethyl alcohol
o Isopropyl alcohol
o Denature proteins and disrupt membranes of microbes
o Works better than just soap

o Fl, Cl, I, BR
o Intermediate
o Damage enzymes (determines inhibition/death)
o Used in hospitals, water supply, bleach

o H2O2→ can disinfect and sterilize surfaces
o O3 (treat drinking H20)
o kill by disrupting (oxidizing) enzymes
o high levels of disinfectants + antiseptics

o Lower surface tension of water → disrupts membranes (soaps, detergents—pure surfactants vs better working by decrease ST, disrupts proteins in the membrane by the positive charged ends of detergent interacting with negative charged ends of bacterial surface—almost pulling apart the cell)

o Heavy metals can turn into heavy metal ions→ denature proteins (can be toxic to humans)
o Thimerosal in vaccines (mercury compound to preserve)

o Compounds contain CHO @end
o Crosslink proteins (knocking out activity of proteins)
o Inactivate nucleic acids
o Ex. gluteraldehyde
• Diluted it can disinfect and sterilize
o Formaldehyde (formalin)
• Used in embalming/disinfectant

therapeutic drug= chemical used in treatment, relief or prophylaxis of disease

antimicrobial

o =chemicals that are derived from bacteria or molds
o inhibits/destroy other microbes
o synthetic= made in lab
o semisynthetic= come from bacteria and mold where lab tweaks them

most generic = all antimicrobes, doesn’t matter origin

o Narrow spectrum→ effective against limited microbes
o Broad spectrum→ much greater variety, active against a wider range of different microbes
o KEY= want to destroy microbe without harming the host!

o first antimicrobial
o specific dyes stain certain microbes and not animal tissues
o ? maybe drugs can selectively kill microbes, not human tissue
o tested theory by treating syphilis, started playing with arsenic 606th try with salvarsan—used therapeutically for few years

o plate of S. aureus (plate got contaminated with mold)
o Mold= penicillium noatatum (isolated “penicillin”) (bactericidal)

o working with dye and bacteria
o used red dye (protonsil—active against certain bacterias and infection in animals)
o same microbes in test tube (nothing happened/dye not effective)
o Drug was altered to be “active in body”→ changed protonsil to sulfonamide → first sulfa drug

Drugs that effect the bacteria cell wall—Gram positive= more succeptible and gramp-negative less succeptible b/c OM, so drugs can’t get in

• Inhibit crosslink of peptidoglycan; between lines of NAM-NAG-NAM-NAG
• Penicillin= bactericidal; natural and synthetic forms (lyse, rupture and blow up)
• Cephalosporin= semi-synthetic

• Inhibits early cell wall synthesis, disrupts polysaccharide back bone, for life threatening infections; Staphylococcus infection, neurotoxic, last line of defense/ BIG GUNS. Microbes are becoming resistant

• In Neosporin
• Disrupts polysaccharide back bone
• For streptococci + staphylococci
• For Gram + (works really well)

• Used to treat TB
• TB caused by microbe called mycobacterium tuberculosis
• Has waxy coating → cell wall is composed of mycolic acid
• Isoniazed inhibit mycolic acid synthesis (leaky cell wall) (first line of defense for TB)
• Secondary treatment= Ethambutol → given separately to avoid resistance
• Inhibits incorporation of the mycolic acid into cell wall (explodes)

inhibits DNA girase of prokaryotes (which is important in unwinding DNA, without they can’t replicate) Potent, broad spectrum

inhibits RNA polymerase—blocks RNA synthesis, leprosy/TB, hepatoxic, resistant microbes

inhibits DNA girase of prokaryotes (which is important in unwinding DNA, without they can’t replicate) Potent, broad spectrum

inhibits RNA polymerase—blocks RNA synthesis, leprosy/TB, hepatoxic, resistant microbes

• broad spectrum
• block the enzymes that make purines and pyrimidine—competitive inhibitors of KABA, which is a substrate for the enzyme that converts PABA (enzyme blocked by sulfonamide) to DHFA (enzyme) to THF (enzyme) to purine & pyramidines→ DNA & RNA

• PABA→ DHFA (blocked by thrimethoprim)—THF—DNA
• Binds to enzyme that converts DHFA to THF

• Quinine drugs
• Extracted from bark of cinchona tree
• Now synthetic—chloroquine
• For plasmodium to cause malaria, drug inhibits enzyme and changes heme (in RBC) to nontoxic form, then heme is toxic to

prokaryotic ribosomes diff’t ours

• Broad spectrum
• Bind 50S (large) ribosomal subunit
Prevents peptide bond formation so incoming AA can’t bind

• interferes with attachment of tRNA to mRNA (on ribosomes)

• (group = macroliders)
• bind 50S
• prevent movement of the ribosome along the MRNA

• change shape of 30S
• so codons read improperly
• ex. streptomycin

• disrupt membrane of Gram – bacteria (outermost membrane/outer membrane)
• cationic detergents, disrupt bilayer, lead to burst
• nephrotoxic/renal toxic/neuromuscular toxic , effect the kidney’s nephron

• antifungal
• binds to ergosterol (like the cholesterol in our cell membranes)→ loss of selective permeability
• Human side effects→ may be somewhat susceptible because similar to cholesterol

• inhibit the enzymes that makes ergosterol
• mostly topical medications
• ex. ketoconazole, miconazole

o Interfere with viral replication by: blocking entry to cell, preventing assembly, inactivate replication
o Many antiviral are nucleotide analogs which inactivate replication when they are incorporated into the viral nucleic acids

• analog of guanine (G of DNA) gets put in every time a G is supposed to go in and therefore the fake G makes it impossible to replicate later on
• treat herpes viruses
 herpes simplex virus (cold sore/genital herpes)
 varicella foster—causes chicken pox/shingles

o Random chromosomal mutations (can help survive)
o Transfer of plasmids from one resistant strain to non-resistant strain

1. Enzyme made that inactivate the drug
2. Decrease the permeability and therefore drug uptake/absorption
3. Change in the affinity or # of receptors
4. Modification of essential metabolic pathways