UF Bacterial Pathogens MCB4203 Exam 1

1.1 Robert Hooke

cell term first time, saw microbes for first time

1.1 LEEUWENHOEK

1600s, 500x microscope

1.1 LINNAEUS

father of taxonomy

1.1 REDI

red meat experiments in sealed vs unsealed jays, said yes to spontaneous generation

1.1 NEEDHAM

he BOILED FLUIDS... YES to SPON GEN AGAIN

1.1 Spallanzi

NO SPON GEN BC CLOSED JARS WITH FLUID TO BOIL BC AIRBORNE PATHOGENS

1.1 PASTEUR

GERMS, VACCINE, NO TO SPON GEN

1.1 COHN

BACTERIA STRUCTURE AND ORGANIZED TAXONOMY... DISCOVERED ENDOSPORES

1.1 Koch

DISEASE-MICROBE CAUSE, PURE CULTURE, 4 Koch Postulates

1.1 Koch Postulates - steps and aka

aka germ theory

-isolate

-culture

-reproduce

-identify

1.1 Gram neg

double membrane

lps on outer

periplasmic space between = peptidoglycan

1.1 Gram pos

one mem with peptidoglycan + LTA

1.1 mycoplasma

3 layer cell membrane

NO CELL WALL

1.1 mycobacteria

like gram pos bc one membrane

glycolipids like myolic acid

1.1 Helicobacter pylori

human coevolution where chronic pathogens

may become less virulent over time

1.1 the microbiome

a microbial community, is considered an ORGAN and colonizes various parts of our body

1.1 Yersinia pestis

plague, gram neg, 3 types all with high death rate

1.1 spont generation 3 options

life from...

asexual reproduction

sexual reproduction

nonliving matter

1.2 AMR timeline

Antibiotics introduced in the 1940s and 1950s

Antibiotic resistance by the 1970s

1.2 bacteria still a concern today? main reasons

1. amr 2. infectious diseases 3. food+water infections 4.post surgery + wounds 5. modern medicine

1.2 Tuberculosis returned in the

1990s

1.2 food+water pathogen EXAMPLES

salmonella, campylobacter, e coli

1.2 E coli O157:H7 meaning

O antigen=LPS

H antigen=flagella PROTEIN

K antigen=polysaccharide capsule

1.2 wound infection Iraqbacter

Acinetobacter baumannii, soldiers, HIGH AMR

1.2 burn wound Pseudomonas aeruginosa

high drug resistant

1.2 opportunistic pathogens examples

Burhkholderia cepacia Acinetobacter baumannii IRAQBACTER

Pseudomonas aeruginosa Klebsiella pneumoniae

1.2 modern medicine - B cepacia

spread by mouthwash, nasal spray, direct contact in hospitals in 90s... cause pneumonia

1.2 Bioterrorism Agent A

WORSE Easily disseminated from person-to- person

High mortality rates

Huge public health impacts

Social disruption

Public health preparedness PLAGUE EXAMPLE

1.2 Bioterrorism Agent B

Less easy to disseminate

Agent B • Moderate morbidity and low mortality rates

• Require enhancements of diagnostic by CDC

• Enhanced disease surveillance SALMONELLA, ECOLI, SHIGELLA

1.2 Infection can be good news

H. pylori - increases risk of things like gastric ulcers BUT decreases risk of IBD, celiac disease

1.2 Microbial Shift aka

Dysbiosis

1.2 Dysbiosis

Certain illnesses may occur when the number of beneficial microorganisms decreases or when the number of harmful microorganisms increases. Bacterial shift diseases can lead to clinical outcomes.

EXAMPLES C Diff, bacterial vaginosis where lactobacilli is too low

1.2 One Health

One Health is a collaborative, multisectoral, and transdisciplinary approach that involves professionals in veterinary medicine, biology, social sciences, humanities, engineering, medicine, and earth sciences.

2.1 Cleaner

→ soil removal SOIL ONLY

2.1 Sanitizer

reduces the number of bacteria BACTERIA ONLY

2.1 Disinfectant

kills fungi, bacteria, viruses MAIN 3

2.1 Sterilant

STRONGEST eliminates bacteria, fungi, viruses, spores SPORES TOO

2.1 adaptive immunity special players (easy to forget)

cytokines

2.1 innate immunity special players (easy to forget)

NKs, phils, complementl, mast, DC

2.1 Agent External, Objects

→ disinfectants, sanitizers

2.1 Agent External, Body

→ antiseptics, germicides

2.1 Biofilm

stops microbial agents

extracellular polymer substance EPS

limits transport with electroatstic or hydrophobic interactions

biofilm=nutrient gradient

reduced effect of antimicoro agents

2.1 Cell wall and efflux pump

change in wall or memrabne = resistance

bacteria can REMOVE AGENTS WITH EFFLUX - PUMPS host defense OUT OF bacteria CELL

2.1 Intracellular alteration

antimicro agents destroy internal bacteria functions andprocesses

mutations of genes or changes to metabboism change the procdsees medicine was intended for = now restisant

2.1 physical defense - chemical barriers

enzyme in fluids - sweat and saliva

2.1 good bacteria

Examples:

Staphylococcus epidermidis

Propionibacterium acnes (now called Cutibacterium acnes)

Corynebacterium

lactobacillus

some ecoli

2.1 innate immunity time

hours

2.1 adaptive immunity time

days

2.1 skin + mucus

barrier system

2.1 ECM - fibronectin

GLYCOPROTEIN, cell adhesion by bind to integrin, ecm

2.1 integrin

TRANSMEMBRANE PROTEIN, moderate interactions between cell and ECM

2.1 dermis

dermis=salt and collagen

2.1 Langerhans cells

DC cell in skin epidermis

2.1 desquamation

skin shedding

2.1 keratin

protein not easily degraded by bacteria, keratinocytes die frequently

2.1 skin environment, inhospitable...

Low pH

Low temperature

Arid conditions

2.1 hair follicles and glands

potential bacteria breach area bc open pore to environment, so has special protections like lysoszomes and toxic lipids, Overgrowth causes boils or acne

2.1 bacteriocins in skin

skin / good bacteria produces toxins and growth inhibitors like bacteriocins to stop bad bacteria

2.1 skin invasion is often tra...

transient (TRANSIENT=TEMPORARY) due to permanent good bacteria colonizers

2.1 Skin infection with commensal bacteria

white and black head

2.1 whitehead

trapped sebum with P. acnes

2.1 blackhead

dried and trapped sebum plug

2.2 Contain just one epithelial layer

Eyes

Respiratory tract (lungs, trachea)

Gastrointestinal tract

Urogenital tract

2.2 some mucus membranes are vulnerable bc

one cell thick, Exist in moist conditions, 37 degrees temperature, neutral pH, and high humidity

2.2 skin cell contact JAM

JUNCTIONAL ADHESION MOLECULES JAM molecules are protein structures that connect the cells.

2.2 Mucosal cells rapidly

divide and constantly shed.

2.2 Lysozyme cleaves bacterial...

PEPTIDOGLYCAN between the N-acetylglucosamine molecule and N-acetylmuramic acid.

2.2 Lysosome best against gram

gram pos

2.2 Lysosome can sometimes effect gram

gram-negative bacteria if the outer membrane is disrupted.

2.2 Lactoferrin

IRON STEALER FROM BACTERIA... AMP!!!!!!!!! an iron-binding protein that makes iron unavailable to bacteria.

2.2 Lactoperoxidase

AMP for bacteria bc makes CYANIDE. HEME molecule... It is a peroxidase, so it contains a heme molecule. h202 into cyanide scn-

2.2 Phospholipase

degrades the cytoplasmic membrane (phospholipids) in order to lyse bacterial cells.

2.2 Paneth cells have _ and are located in _

AMP in small intestine

2.2 AMPs can

Can form channels, HOLES, and collapse proton motive force in bacteria = LYSE

2.2 AMP example is

defensin + cathlecdin + histatin

2.2 AMPs are particularly important where

inside vacuoles that are formed within the phagocytic cells.

2.2 mast cells

inside MALT, M (both microfold and mast) cells engulf bacterial cells and deliver them to phagocytic cells.

2.2 MALT where and types

submucus in galt (gut, gi), balt (bronchus), nalt (nasal)

2.2 Lamina propria is

MUCUS TISSUE right under epithelial cells of the GI tract, many immune cells

2.2 Peyer's patches are

masses of lymphatic tissue in the SMALL INTESTINE and important to the immune system

2.2 food born pathogens can survive in stomach bc

Some food-borne pathogens such as E. coli, Salmonella, and Campylobacter have an acid-tolerance response, activated at pH 4.

*2.2 H pylori survive in gi tract how + symptoms + location

Infects stomach

Can be asymptomatic but can lead to peptic ulcers

Lives in the MUCIN layer near NORMAL LAYER

Possesses adaptations to protect itself from acidity

2.2 H pylori move thru mucus bc

The CHEMOTAXIS and cell shape help with translocation through the mucus.

*2.2 H pylori main weapons

urease, flagella, enzymes/effectors, chemotaxis

2.2 H pylori urease

urease = urea to ammonia, raises ph locally because ammonia is basic, so ph locally is less acidic and more neutral... it can survive

*2.2 Bile Salts are

steroids with detergent-like properties

*2.2 Bile salts are made in _ and stored in _

made in the liver and stored

in the gallbladder

*2.2 Bile salt purpose

Neutralize stomach acid to help with fat digestion

Disrupt bacterial membranes

2.2 Rapid flow

SMALL INTESTINE - bacteria dont have time to colonize bc so quick

2.2 Bladder is

sterile

Urine acts as ANTISEPTIC and helps remove bacteria

2.2 Urethra's sphincter

prevents the ascent of bacteria to bladder and kidneys

2.2 Prostate gland essential in

producing defensins (AMPs)

2.2 upper respiratory tract generally has a __ density of microbiota compared to the lower respiratory tract

higher density of microbiota compared to the lower respiratory tract (which includes the nasal cavity, pharynx, and part of the larynx)

2.2 lower resp is

trachea + lungs

2.3 Edward Jenner

FIRST SMALLPOX VACCINE... milkmaid with cow pox less likely to get small pox

unaffected by disease

he made the vaccine

COW POX---> SMALLPOX vaccine (do not confuse with chicken pox)

2.3 ELIE METCHNIKOFF

founded CELLLular IMMUNOLOGY, saw INFLAMMATION + WBCs

2.3 tho some discoveries in late 1800s...

most work done in past 100 years

2.3 Paul Erlich

→ side-chain theory explaining specificity of ANTIBODY-ANTIGEN reaction (HUMORAL immunity)

2.3 Lymph system

nodes and vessels with lymph fluid... immune cells are also in blood, spleen, thymus, liver, lung, brain

2.3 immune cell are thru out

entire body - mutli organs