BIO230 Microorganisms and Bacteria

• Bacteria
• Yeasts
• Molds
• Viruses
• Protozoa

• Animal
• Plant
• Monera (bacteria)
• Fungi (yeast/molds)
• Protista
• (*viruses are not classified because they are not living organisms.)

• brain & spinal cord
• heart & blood
• kidneys

Always cause harm

*True & Opportunistic pathogens make up about 5% of all known bacteria.

• May cause harm if the right conditions exist.
• -Weakened immune system
• -Not located in normal location (UT infection)

*True & Opportunistic pathogens make up about 5% of all known bacteria.

• 1. animal, plant, fungi, protista
• 2. present w/ nuclear membrane
• 3. more than 1
• 4. linear
• 5. Yes
• 6. Lots
• 7. Animals; no, Plant & Fungi; yes (cellulose/starch), Protista; no
• 8. some do
• 9. 9+2 protein

• 1. Monera
• 2. no Nucleus
• 3. 1
• 4. Circular
• 5. No
• 6. Few
• 7. Yes - peptidoglycan
• 8. Some do
• 9. Single protein

• 1. Not living; viruses
• 2. no Nucleus
• 3. 1
• 4. Circular? or Linear?
• 5. No
• 6. None (no cytoplasm)
• 7. No
• 8. No
• 9. No

• Spherical in shape
• 0.5 - 1.0 μm
• Single (monococcus)
• Pairs (diplococcus
• Chains (streptococcus)
• Bunches (staphylococcus)
• Groups of 4 (tetrad)
• Cubes (sarcina)

• Rod shaped (elongated spheres)
• 1.0 - 5.0 μm long, 0.5μm in diameter Single (monobacillus)
• Double (diplobacillus)
• Chains (streptobacillus)

• Spirillum
• -5.5μm long, 1.0μm diameter
• -Spiral shaped

• Spirochete
• -5.0 - 25.0μm long, 0.5μm diameter
• -Tight spiral shaped

• Vibrio
• -Curved (comma) shape

Oval shaped - in between a coccus and bacillus

-maintains proper shape & size of bacteria -Prevents bursting of bacteria

Single thick layer of Peptidoglycan (PG)

• 1. Lipopolysaccharide (LPS)
• 2. Lipoproteins (LP)
• 3. Phospholipid (PL)
• 4. Peptidoglycan (PG)

Does not cause harm.

When the cell dies the LPS layer becomes an Endotoxin.

• 1. Stimulates inflation.
• 2. Damages human cell membrane causing loss of cell fluid.
• 3. Human cell necrosis (death) due to loss of cell fluid.

• 1. Nausea
• 2. Vomiting
• 3. Diarrhea
• 4. Loss of fluid
• 5. Dehydration

• 1. Urethritis
• 2. Cystitis
• 3. Nephritis (kidney)

*80% of UT infections caused by G- bacteria

• 1. Gonorrhea
• 2. Chlamydia
• 3. In males; urethritis, prostatitis, epididymitis
• 4. In females; cervicitis, pelvic inflammatory disease (PID)

Penicillin & Cephalosporin

• -Block formation of PG in the cell wall
• -Used mostly against G+ bacteria

• 1. Regulates what enters and leaves the cell.
• 2. Site of cell wall repair & synthesis.
• 3. Site of energy production in bacteria.

Binary fission (splits in 2); asexual reproduction of bacteria

• 1. Helps separate DNA
• 2. Builds new crosswall/septum to divide new cells

Bilayer lipoprotein

• 1. Small molecules move by passive transport (osmosis or diffusion)
• 2. Large molecules move by active transport (attaching to proteins)

None

1. Bacitracin-damages cell wall and membrane (topical).

• 2. Polymyxin B - damages membrane (topical)
• -Aerosporin
• -Neosporin

• 3. Soaps & Detergents
• a. Scrubbing and lathering damages cell walls and membranes.
• b. Synthetic detergents - less lathering but add chemical to damage membranes; Iodine (iodophore), Alcohol (tincture), Ammonia - common Quaternary NH₃ compound called Quats (zephiron)

4. Carbolic acids - damaged membrane; Lysol, Osyl, Cresol, Phenol, Phenol mixed w/ soap = hexachlorophene

Motility (motion)

• 1. Monotrichous flagella - single tail
• 2. Amphitrichous flagella - single tail from both ends of bacteria
• 3. Polar lophotrichous flagella - multiple tails from one end of bacteria.
• 4. Lophotrichous flagella - multiple tails from both ends of bacteria.
• 5. Peritrichous flagella - multiple tails from all sides of bacterial cell

Made of protein called Flagellin

1. L-Ring attaches to the LPS, LP, & PL layers of the cell wall.

2. P-Ring attaches to the Peptidoglycan layer of the cell wall.

3. S-ring attaches to the periplasmic space between the cell wall & cell membrane.

4. M-Ring attaches to the cell membrane.

• 1. Chemotaxis - response to chemicals
• a. When a chemical reaches the cell membrane the cell membrane will begin to vibrate, starting a chain reaction through the M, S, P and L rings (in that order)

• 2. Phototaxis - response to light
• a. Bacteria do no like light, in particular the heat

3. Magnetotaxis - response to a magnetic field.

No direct role. Although, the flagella can move the bacteria to a location where other parts of the bacteria can cause harm.

None

Attachment

• 1. Attachment to a food source.
• 2. Attachment to prevent being flushed out.
• 3. Attachment to other bacteria for sexual conjugation. Uses special pili called a fertility pilus (F-pilus) to transfer DNA material to another cell.

Made of a protein called Pilin

No direct role. Although piliated bacteria are harder to flush out.

1st pili attaches to mucus membrane of genital tract

2nd pili attaches to surface of white blood cells (neutrophils), prevents neutrophil from phagocytizing bacteria

3rd pili attaches to sperm

4th pili called F-pili allow for transfer of genes for antibiotic resistance.

None.

Regulates all cell activity and determines all cell characteristics.

Deoxyribose Nucleic Acid (DNA)

• 1. 1
• 2. Circular
• 3. No
• 4. 1mm

No direct role in causing harm. Although the DNA does code for all harmful characteristics of the bacteria.

Malidixic acid

Extra chromosomal pieces of DNA

Plasmids are what is transferred through F-pili during sexual reproduction.

Most plasmids code for antibiotic resistance.

Site of protein synthesis.

RNA and Proteins

30S and 50S

No direct role in causing harm. Although, some bacteria produce exotoxins made of proteins the ribosomes synthesized.

1. Antibiotics will cause the 30S and 50S components to separate.

2. Antiseptics & Disinfectants will damage ribosomes and the proteins made by ribosomes.

• Streptomycin
• Erythromycin
• Tetramycin
• Azithromycin
• Clindamycin
• Doxycycline

*there are other side effects when using these antibiotics.

1. Alcohols (tinctures) - methanol, ethanol, isopropanol,

• 2. Heavy metals
• a. Silver - used as 1% AgNO₃ , prevents ophthalmia neonatum blindness from gonorrhea.
• b. Mercury - used topically as merthiolate or mercurochrome

• 3. Halogens
• a. Fluorine (fluoride), all water is fluoridated, Prevents oral infections, Toothpastes, mouthwashes
• b. Chlorine, Public water (drinking & recreational), Prevents gastrointestinal infections, Sodium hypochlorate - bleach
• c. Iodine, Skin antiseptic
• d. Bromine, Used in hot tubs

4. Aldehydes - very strong antibiotic, Formaldehyde, Glutaraldehyde

5. Ethylene oxide gas, used to destroy microorganisms in highly infectious waste, Gas sterilizer

• 1. Prevents phagocytosis by white blood cells
• 2. Site of stored sugars for bacteria
• 3. Prevents dehydration of bacteria
• 4. Prevents viral infections of bacteria
• 5. Attachment

Capsules are made of a complex of sugars. Mucopolysaccharides or mucocomplex

Blockages

• -Bacteria with capsules can infect the respiratory tract (bronchi & lungs)
• -Pneumonia
• -Clogs respiratory passages causing heart to work harder

None.

Survival in harsh environments.

Sporulation - bacterial spore synthesis

• 1. Vegetative cell,bacteria without spore, copies DNA
• 2. then copies ribosomes
• 3. Surrounds spore with membrane and wall
• 4. Surrounds spore with 3 protective layers - this is called a forespore

• 1. Cortex - calcium & proteins
• 2. Spore coat - dipicolimic acid (DPA)
• 3. Exosporium - calcium & peptidoglycan

No direct role in causing harm. Spore must germinate into a bacteria cell to cause harm.

• 1. Anthrax - Bacillus anthraces
• 2. Tetanus - Clostridium tetani
• 3. Botulism - Clostridium botulinum
• 4. Gas gangrene - Clostridium perfringens
• 5. Clostridium difficile (C. diff)

• 1. Bacillus anthraces
• 2. G+ aerobe
• 3. found in deep soil
• 4. Spore can be breathed in dust particles, or on skin.
• 5. Necrotizing exotoxin.

• 1. Clostridium tetani
• 2. G+ anaerobe
• 3. Intestines of large animals > animal feces > in the soil.
• 4. Spore must be introduced into an anaerobic environment via a puncture wound.
• 5. Neurotoxin called tetanospasmin

• 1. Tetanospasmin blocks and enzyme called Cholinesterase.
• 2. Cholinesterase breaks down a neurotransmitter in the synapse called Acetylcholine. (acetylcholine sends messages to the brain to contract muscles)
• 3. In the absense of Cholinesterase Acetylcholine is not broken down and the muscles stay contracted.

Effects the head and neck area first

• 1. Clostridium botulinum
• 2. G+ anaerobe
• 3. Intestines of large animals > animal feces > in the soil.
• 4. Food grown in soil containing Botulism is canned, introducing it into and anaerobic environment. Germination and toxin production is done in can. (there is also puncture wound Botulism.)
• 5. Neurotoxin called botox

Botox blocks the production of acetylcholine, causing all muscles to relax. Eventually, you suffocate because your diaphragm muscle will not contract.

• 1. Clostridium perfringens
• 2. G+ anaerobe
• 3. Intestines of large animals > animal feces > in the soil
• 4. Spore must be introduced into an anaerobic environment via a puncture wound.
• 5. Necrotic and kills cells & tissues

1.Tissue necrosis, softens, wet, discolored, bad odor, a gas is produced causing tissue to stretch

2. Gets into blood stream and vital organs leading to organ death - crepitation.

• 1. Clostridium difficile (C. diff)
• 2. G+ anaerobe
• 3. Spores are found in intestines, including humans
• 4. Spores can get into abscesses in lining of intestines
• 5. Causes chronic intestinal problems

(Spores can also get onto sores on the skin and cause severe infections)

• There are no antibiotics that can kill spores.
• Antibiotics can only be used after spores germinate.