1. chromosome replication & separation

2. cell membrane pinches in tow

3. cell wall septum forms between 2 daughter cells

time required for cell division to occur

Ranges from 20 min (E. coli) to months (M. leprae)

lag phase

resting but no division BUT high metabolic activity

ADAPTATION to new environment

store nutrients

synthesize enzymes

prepare for division

stationary phase

cell death = cell death

*sporeformers form spores in late log and early stationary*

0-20 C

no known human psychrophiles

20-40 C

body temp 98 F

most common human pathogen

(special group: Pathogenic Psychrophiles)

staphylcoccus aureus

salmonella sp

proteus vulgaris

yersinia enterocolytica (blood bag contamination, endotoxin shock)

80 C +

hot springs, deep sea thermal vents

Archae

2-15% salt

(Vibrio vulnificus)

oxygen is toxic to them

C. tetani, C. botulinum, C. perfringens (gas gangrene/ food poisoning)

preferably grow with oxygen; can grow without it

Most human pathogens

requires extra CO2 (3-5%) for growth

ex: Neisseria

candle jar

used in fermentation of dairy productions and pickles

ex: Lactobacillus

iron-loving

protein that can infect (but not replicate) and cause disease

-very stable, doesn't degrade well

ex: CNS disease Scrapie, Kuru (canabalism), mad cow disease

eukaryotic; similar membrane to euk but also have cell wall made of chitin

-treatment can be toxic because targetting eukaryotic cells

single chromosome

450-7500 genes

aerobic or anaerobic

many classifications (shape, temp, gram stain, etc)

stains blue/purple

phospholipid bilayer

thick peptidoglycan layer (40+ layers--resists lysis by complement but CAN be opsonized)

teichoic acids & lipoteichoic acids

other proteins or carbohydrates (M protein)

outer membrane (sepsis)

periplasmic space (contain b-lactamases)

single layer of peptidoglycan

porins

*Lipopolysaccharids LPS- important in pathogenesis & mediate septic shock (Lipid A)**

multi-organ failure

-bacteremia- sepsis (bacteria in blood)

-mediated by Lipid A (binds macrophages, release of cytokines)

-Lipid A=endotoxin

E.coli, Klebsiella, Pseudomonas, Bacteroides

gram positive (4o + layers)

cleaved by lysozyme (tears, saliva, mucus) at beta-1,4-likage

N-acetyl glucosamine & N-acetyl muramic acid backbone chains linked by variable tetrapeptides

*diaminopimelic acid linked to LPS-unique to GRAM NEG*

Bacitracin-sensitive (b-lactam antimicrobial)

Teichoic acids-threaded throughout and permeate the layer

PBP's- Penicillin-binding proteins: cross-link with penicillin & transport

muramyl dipeptide: result of bacterial degradation

locomotion & movement

H antigen

Gram (+): 2 rings in flagella insertion

Gram (-): 3 rings (outer membrane penetration)

repeating units of 3-5 sugars

smooth with/rough without (LOS-Lipoligosaccharide)

antigenic/variable

Mycobacteria

similar to G+

cell wall composed of fatty acids & waxes

Non-reversible staining

K antigen; not impermeable

polysaccharide--causes Ab response

virulence factor: complement unable to phagocytize; must opsonize by Ab

B. anthracis (poly-glutamate capsule), S. pneumoniae (India ink-clearing)

NOT capsule

extracellular polysaccharide;  biofilms,  grows on inanimate objects

whip-like motion

40 gene subunits encode for flagella

monotrichous- single flagella

peritrichous-flagella throughout entire surface

locotrichous- flagella on a specific pole

Damage to DNA

Protein denaturation

Disruption of cell membrane or wall

Removal sulfhydryl groups on proteins

1. Transformation

2. Transduction

3. Conjugation

Antibiotic resistance and virulence

"competent" recipient cell uptakes donor DNA

recombination gives altered profile

Genetically transformed cell= aquired resistance or virulence trait

Conjugation

transfer of genetic material (usually plasmids) through direct cell-to-cell contact (sex pili)

nicking by enzyme, DNA replication, moves through conjugation tube, cells move apart, plasmid forms

plasmids-independently replicating

most common in GI tract

Bacteriophage sheath injects DNA into bacterial cell

Recognition of receptors (LPS, Pili, Lipoprotein) by the tail fibers

Transducing phage=phage DNA + host DNA

Electrostatic Charges overcome by:

Pili

Lipteichoic acid (F & M proteins)

hair-like apendages for adhesion

ex: E. coli binds to mannose-containing receptors on epithelial cells

produced inside gram-positive bacteria (Staph & Strep)

secreted--cell does not have to lyse

Diptheria toxin

exotoxin

Fragment A: "active site"

inhibits protein synthesis by blocking elongation factor 2 (EF2)

Fragment B: "binding site"

binds exotoxin to epithelial cell and is internalized

-way that an organism alters its antigens so that it can avoid the immune system--unable to recognize Ag

N. Gonorrhea

-recombination, changing the pili, altering the antigens

ways bacteria are pathogenic inside the cell

Mycobacterial diseases

SARS

ssRNA

Herpes; type 1 & 2; CMV; EBV

dsDNA

HPV; genital warts; cervical cancer

dsDNA

HIV/AIDS

ssRNA

influenza

ssRNA (segmented)