PC 2 mod 1.1 lec 1

rigid wall of bacteria contain ______, ______ increase infectivity and they replicate by _______

- peptidoglycan

- virulence factors

- binary fission

gram stain steps

1. set bacteria and fix onto slide using ______

2. _______ and wait ____ secs

3. wash off with _____ and flood with ______ and wait _____ secs

4. wash off with ______ then ______ with _____

5. counter-stain with ______ and wait _____ sec then wash off with _____

- heat source

- crystal voilet stain --> 60 sec

- water --> iodine --> 60 sec

- water --> decolorize --> 95% alcohol

- safranin --> 30 sec --> water

flooding with _____ during gram stain will trap crystal violet into cell wall

iodine

gram positive is _____ color

gram negative is _____ color

- blue/purple

- red/pink

4 major shapes of bacteria...

- cocci (sphere)

- bacilli (rod)

- spirochete (spiral)

- pleomorphic

3 gram positive cocci

- staphylococcus

- streptococcus

- enterococcus

staphylococcus, streptococcus, and enterococcus are all gram POSITIVE/NEGATIVE and COCCUS/ROD/SPIRAL

- positive

- coccus

gram negative cocci

neiseria (diplococci)

neisseria is gram POSITIVE/NEGATIVE and COCCUS/ROD/SPIRAL

- negative

- coccus

staphylococcus is _____

streptococcus is _____

enterococcus is _____

neiseria is ______

- cluster

- chain

- pairs and chains

- dilococci

2 gram positive rod

- listeria

- clostridium

listeria and clostridium are gram POSITIVE/NEGATIVE and COCCUS/ROD/SPIRAL

- positive

- rod

6 gram negative rods

- e. coli

- shigella

- klebsiella

- serratia

- pseudomonas

- bacteoides

e. coli, shigella, klebsiella, serratia, pseudomonas, bacteoides are all gram POSITIVE/NEGATIVE and COCCUS/ROD/SPIRAL

- negative

- rod

gram-negative spiral example

treponema

treponema is a gram POSITIVE/NEGATIVE and COCCUS/ROD/SPIRAL

- negative

- spiral

4 members of normal flora in colon...

- bacteroides species

- clostridium species

- enterococcus species

- e.coli species

e. coli and other coliforms are common in _____ and ______

- colon

- vagina (genitourinary tract)

normal flora in skin are... (3)

- c. acne/p.acne

- staph aureus

- staph epidermidis

2 normal flora on skin and nose

- staph aureus

- staph epidermidis

- haemophilus (in nasopharynx)

staph aureus can cause... (4)

- boils/abcessess

- bacteremia

- pneumonia

- endocarditis

streptococcus pyogenes can cause... (3)

- cellulitis

- necrotizing facitis

- acutre pharyngitis (strep)

enterococci faecalis/faecium can cause... (1)

intrabdominal infection

E.coli can cause ... (2)

- UTI

- intrabdominal infection

pseudomonas aeruginosa can cause... (1)

pneumonia

is pseudomonas aeruginosa normal flora? gram POSITIVE/NEGATIVE? COCCUS/ROD/SPIRAL?

- no

- negative

- rod

clostridium tetani is a _____ that can cause ____

- anaerobe

- tetanus

bacteoides gragilis is a ______ that can cause ______

- anaerobe

- intrabdominal infection

3 infection portals of entry

- ingestions

- inhalation

- contact

Gives rigid support, protects against osmotic pressure; is site of action for many antibiotics

peptidoglycan wall

peptidoglycan wall gives rigid support, protects against______; is site of action for many _______

- osmotic pressure

- antibiotics

GRAM POSITIVE/GRAM NEGATIVE have thicker, multilayer peptidoglycan while GRAM POSITIVE/GRAM NEGATIVE have thinner, single layer peptidoglycan

- positive

- negative

gives cell structure, protects against antibiotic attack, allows cell division and is a surface antigen

teichoic acid

DELETE

- antibiotic attack

- cell division

- surface antigen

teichoic acid is found in gram POSITIVE/NEGATIVE

positive

barrier against antibiotics and modules response by host immune system

lipopolysaccharides

lipopolysaccharides are barrier against _____ and modulates response by _______ system

- antibiotics

- host immune system

lipopolysaccharides are found in gram POSITIVE/NEGATIVE

negative

gram positive have LOW/HIGH lipid content and gram negative have LOW/HIGH lipid content

- low

- high

passage on nutrients, antibiotics, and site for development of antibiotic resistance

porin channel

porin channels pass _____ and _____ which are HYDROPHILIC/HYDROPHOBIC and site for development of _______

- nutrients

- antibiotics

- hydrophilic

- resistance

porin channels are found in gram POSITIVE/NEGATIVE

negative

which is more susceptible to antibiotics, gram positive or negative?

positive

peptidoglycan has a _____ backbone with alternative _____ and _____

- carbohydrate

- NAM

- NAG

_____ hang off NAM of peptidoglycan and are crosslinked by ______ known as ______

- D- and L-amino acids

- transpeptidase enzymes

- penicillin binding proteins

______ are key site of antibiotics targeting peptidoglycan

penicillin binding proteins

piece of the outer membrane lipopolysaccharide (LPS) of gram-negative bacteria

lipid A

lipid A is release when bacteria undergoes ______ and can cause _____ secondary to infection

- lysis

- fever/shock

lipid A is an ENDOTOXIN/EXOTOXIN

endotoxin

_____ means it is inherent to cell vs ______ means produced and release by cell

- endotoxin (lipid A)

- exotoxins

exotoxins are ______ released by gram POSITIVE/NEGATIVE

- proteins

- both

examples of exotoxins (2)

neurotoxins and enterotoxins

3 adherence virulence factors

- capsule

- glycoclayx

- pili (fimbriae)

gelatinous layer covering bacterium

capsule

capsules limit ability of _____ and allow ______ of bacteria to _____

- phagocytosis

- adherence

- human tissue

polysaccharide coating that allows bacteria to adhere to structures like skin, heart valve and catheters

glycoclyx

glycocalyx allows bacteria to ______ to structures

- adhere

hair like filaments that extend from the cell surface that are shorter and straighter than flagella and mediate attachment of bacteria to receptors

pili/fimbriae

pili/fibriae are found mainly on gram POSITIVE/NEGATIVE

negative

pili/fimbriae mediate attachment of bacteria to specific _______ on human cell surface to initiate infectious process and facilitates attachment during ______

- receptors

- conjugation

2 motility/evasion virulence factors

- flagella

- biofilm

whip-like appendages to move bacteria towards nutrients and other attractants

flagella

flagella are found mainly in gram POSITIVE/NEGATIVE

negative

flagella can help propel bacteria up the _____ into ______ such as _____ and _____

- urethra

- bladder

- e.coli

- proteus sp.

matrix composed of polysaccharides, secreted proteins and extracellular DNA produced by 40-80% of bacteria to evade host defense and protect against biocides

biofilm

biofilms are matrixes composed of ______, secreted ______ and ______ produced by ____% of bacteria to evade host defense mechanism and protect against ______

- polysaccharides

- proteins

- extracellular DNA

- 40-80%

- biocides

highly resistant structures that form when nutrients are depleted or to protect against unfavorable conditions

spores

2 bacteria that use spores

bacillus sp and clostridium sp

spores have no _____ and can remain dormant for ______

- metabolic activity

- years

steps of spore formation...

--> ______ cell

--> developing _____ around _____

--> spore coat around mother cell

--> free ______

--> release back to _____ when conditions are favorable

- vegetative cell

- spore coat --> nucleotide

- endospore

- vegatative cell

does vegetative cell do replication?

no

bacteria replicate via ______

binary fission

bacterial replication steps

--> replication of _____

--> continued ______ of the cell

--> division into 2 identical cells through _____ transfer of DNA

- chromosomes

- growth

- vertical transfer

bacterial replication is ______, meaning one DNA strand from parent and one newly synthesized

semi-conservative

3 types of horizontal transfer of bacteria DNA

- transformation

- transduction

- conjugation

when naked DNA fragments from one bacterium, released during cell lysis, binds to cell wall of another bacterium

transformation

transformation is when when naked DNA fragments from one bacterium, released during cell ______, binds to ______ of another bacterium

lysis

cell wall

virus that infects bacteria carries of piece of bacterial DNA from one bacterium to another

transduction

virus that infects bacteria is called _____ and it does ______

- bacteriophage

- transduction

when DNA (plasmid) is transferred directly by cell-to-cell contact

conjugation

plasmids are double stranded molecules of DNA that are ______ elements which can integrate into _____ of host

- mobile genetic elements

- chromosome

plasmids are used during _____ and possess info about _______

- conjugation

- antimicrobial resistance

4 phases of bacteria growth

1. lag phase

2. log phase

3. stationary phase

4. death phase

lag phase of bacteria is when there IS/IS NOT metabolic activity and it IS/IS NOT dividing and this is _____ time

- is

- is not

- few minutes to hour

log phase of bacteria is making ______ and this is when rapid _____ occurs

- peptidoglycan

- cell division

b-lactam works during ______ phase of bacteria cell growth

log

______ phase is when nutrient depletion or toxic products cause growth to slow until cells ______ balance cells _____

stationary phase/steady state

- replicating

- dying

part of growth cycle where decline in viable organisms

death phase

bacteria use _____ as energy source

ATP

anaerobic bacteria generate ATP through ______ which release ______ from pyruvate

- fermentation (anaerobic glycolysis)

- lactic acid

aerobic bacteria generates ATP through ______ which releases ______ from pyruvate then this enters the ______ which then enters the ______ to produce more ATP

- aerobic glycolysis

- acetyl CoA

- citric acid cycle

- electron transport chain

electron transport chain reduces _____ into _____ to create ATP

- O2

- H2O

toxic 2O2 + 2H+ can be broken down by _____ into _____

- superoxide dismutase

- H2O2

toxic 2H2O2 can be broken down by _____ into _____

- catalase

- 2H2O + O2

requires oxygen to grow for ATP-generation

obligate aerobe

_____ is an obligate aerobe

m. tuberculosis

cannot grow in the presence of oxygen and varies in their response to oxygen. Some can survive but are unable to grow and others are killed

obligate anerobes

______ is an obligate anaerobe

C. tetani

utilize oxygen to generate energy by respiration if it is present, but they can use the fermentation pathway to synthesize ATP in the absence of sufficient oxygen

facultative anaerobes/aerobes

______ is a facultative anaerobe/aerobe

e. coli