MCB3020 Exam 1 Review (Professor Ambivero UCF)

All Living Organisms have a...

Cell Membrane

Microorganism are...

A cellular and cellular

Acellular organisms include

Viruses, Viroids, Satellites, Prions.

Cellular organisms include

Fungi: Yeast and Mold

Protists: Protozoa, Slime mold, Algae.

Bacteria and Archaea (grow in extreme enviorments): Prokaryotes.

Cell wall of Bacteria:

Contains peptidoglycan

N-acetylglucosamine (NAG)

N- acetylmuramic acid (NAM)

NAM has peptides; L-Ala, D-Glu, DAP, D-Ala.

L- is the most common form, D-form makes it harder for bonds to be broken.

Has the ability to turn off production of cell wall on and off.

β(1-4) glycosidic bonds

Interbridges

Glycosidic bonds confer strength in the X direction

The peptidoglycan can be inhibited by two different antibiotics vancomycin and penicillin.

Cell wall of Archaea:

pseudomurein

Different glucose; NAT and NAG

All L-peptides

β(1,3)-glycosidic bonds: lysine does not break, it breaks beta 1,4

All peptides Has L forms, needs specific lysine due to the 1,3 bonds.

Bacteria Genetic Material:

Single celled organisms.

Circular DNA in nucleoid region

Archaea Genetic Material:

Circular DNA in nucleoid region

Eukaryotes Genetic Material:

Linear DNA within a nucleus:

- MRNA translation occurs cytoplasm

Subunit rRNA of Eukaryotes and Prokaryotes:

16s prokaryotes rRNA small subunit of ribosome

18s eukaryotic rRNA small subunit of ribosome.

Result of Endosymbiotic hypothesis?

Gram negative produces the mitochondria

- due to it having two membranes.

Chloroplast generates from cyanobacteria from photosynthesis

Steps:

Engulfment of an endosymbiont ->Genome reduction occurred -> Evolution of organelles

Mitochondria

Chloroplasts

What is the binomial system of nomenclature:

genus name - italicized and capitalized (Escherichia)

species epithet - italicized but not capitalized (coli)

In taxonomic ranks Who has the largest number of organisms?

Domain does.

In taxonomic ranks Who has the smallest number of organisms?

Strain.

Francesco Stelluti

magnifying glass

Robert Hooke

named/coined the term 'cells'

Antony van Leeuwenhoek (1632-1723)

first person to observe microorganisms accurately in 1673 using the simple microscope

Francesco Redi (1626-1697)

1st to test spontaneous generation

showed that maggots on decaying meat came from fly eggs

John Needham

experiment: mutton broth in flasks → boiled → sealed

results: broth became cloudy and contained microorganisms

Lazzaro Spallanzani

experiment: broth in flasks → sealed → boiled

results: no growth of microorganisms

Did it backwards, didn't have growth due to sealing it (Nothing grows without O2).

Swan Neck Experiment: Louis Pasteur

The only scientist who finally disproved spontaneous generation.

Most important microbiologist. Both free of live cells, however one is more closed preventing growth while the neck on the second sterile flask is broken and growth occurs.

Louis Pasteur (1822-1895)

Swan neck experiment

demonstrated microorganisms carried out fermentations

developed pasteurization

Pasteurization is to remove the quantity of bacteria. He helped with food and dairy health issues at that time.

Joseph Lister (1827-1912)

Created sterilization

developed a surgery system to prevent microorganisms from entering wounds

Robert Koch (1843-1910)

Established the relationship between Bacillus anthracis and anthrax

Find the connection between bacteria that causes disease.

What were koch postulates?

- Compare healthy vs sick person

- Isolate the thing that is making them sick on a petri dish to grow as pure culture

-Incoulate them: make the healthy person sick from the sick individual

- Confirm by isolating the microorganism again from the disease host.

What were koch postulates?

- Healthy person can be a carrier

- Not everything grows in a petri dish/ as a pure culture (think of viruses)

-Not all diseases can be transmitted from person to animal

- Diseases might not be caused by one microbes but multiple microorganisms.

Bacteria Shape: Spirllum

Stiff

Bacteria Shape: Spirochete

Flexible

If a Bacteria is small what is the size-shape relationship?

- absorbs nutrients faster

- Large sa/v ratio

- small radius

3/r

If a Bacteria is Large what is the size-shape relationship?

- Worse for nutrient uptake. (slow)

- Smaller sa/v ratio

- Larger radius.

Which is more efficient rod vs cocci?

Rods are more efficient than cocci

Gram negative cell envelope:

Gram negative: cell membrane -> peptidoglycan -> outer membrane (lps)

Gram positive cell envelope:

Gram negative: cell membrane -> peptidoglycan

Bacterial Cytoskeleton Molecules: FtsZ

many bacteria; tubulin homologue

Helps identify the center

S. aureus can only have Ftz

E.coli can have Ftz and Mreb

Bacterial Cytoskeleton Molecules: MreB

many rods; actin homologue

E.coli can have Ftz and Mreb

Bacterial Cytoskeleton Molecules: CreS

maintains curve shape; intermediate filament homologue

- Vivirio

V. cholrae:

FtsZ + MreB + CreS

Storage Inclusions: Carbon Storage

poly-β-hydroxybutyrate (PHB)

Storage Inclusion Amino acids:

Amino acids - cyanophycin granules

What are the two Inclusions - Movement?

Gas vacuoles: fills with gas

- bring up

Magnetosomes: Cytoskeletal protein MamK

Help bacteria find the magnetic field

- bring down.

What is a plasmid?

Extrachromosomal DNA exist and replicate independently of chromosome

What is episomes?

Extra-chromosomal DNA can integrate into the chromosome

What are the Plasma Membrane Functions?

Encompasses the cytoplasm; absolute requirement for all living organisms!

Selectively permeable barrier

Interacts with external environment

- Receptor, Transport and metabolism.

Conjugate plasmids

transfer of DNA from one cell to another

R Plasmids:

Resistant to antibiotics

Virulence plasmids:

Make it harmful to humans

Col Plasmids:

Makes it harmful to other bacteria

Peripheral membrane proteins are located where?

Are not physically attached to the membrane, non-covalent interaction.

Integral membrane proteins are located where?

Integral: are imbedded on the membrane (inside), Hydrophilic outside.

Trans-membrane proteins are located where?

Transmembrane: Goes across the membrane twice, help with transport.

What is a amphipathic lipid?

Has a hydrophilic and hydrophobic lipid allowing nutrients to go in and out.

Bacteria lipids have:

hopanoids (hydrophobic)

Mycoplasma: contains sterols (so do alot of eukaryotes)

Passive difussion:

H2O, O2, and CO2

- Unable to reach saturation

-can easily pass through the membrane freely

Facilitated diffusion

glycerol, sugars, and amino acids

It needs help more energy to complete diffusion;

uses permeases

Active Transport

Goes against the gradient

Involves permeases and ATP

Moving from low concentration to high concentration

Major Facilitator Superfamily (MFS)

Also an active transport, specifically a secondary active transport.

Secondary due to the use of ion gradients instead of atp

Symport: 2 molecules moving in same direction

Antiport: 2 molecules moving in different directions

Symport Secondary Active Transport

Symporters move 2 solutes in the same direction

Lactose permease of e.coli is secondary active transport

H+ and Lactose+ going in together.

Group Translocation

PTS system in E.coli the energy source is PEP.

PEP transports a phosphate to enzyme 1 then HPR then it can go through two different bring Mannitol or glucose.

PEP -> Enzyme 1 -> HPR -> 2a or 2c or 2b depending on the sugar -> mannitol or glucose.

Size of Peptidoglycan in Gram-Negative?

Smaller than gram positive

Stained pink/red

Gram-neg: E.coli

Size of Peptidoglycan in Gram-positive?

Larger than gram negative

Stains purple (crystal violet)

Gram-Positive: S.Aureus

Peptideglycan structure composed of;

N-acetylglucosamine (NAG)

N- acetylmuramic acid (NAM)

β(1-4) glycosidic bonds

Interbridges

Glycosidic bonds confer strength in the X direction

Peptide bonds confer strength in the Y direction

Gram-Negative: Connected form DAP to L-Alaine

Gram-Positive: Lysine, peptide interbridge

DAP and Lysine has 3 attachments.

Gram-Positive Cell wall:

Teichoic acids: gives gram-negative a negative charge.

-glycerol or ribitol polymers

Small Periplasmic space

S.Aureus

NAM and NAG are from what domain? How can they be inhibited?

Bacteria

Vancomycin binds D-ala, D-ala and blocks cross-bridge formaation

Penicilin blocks peptide cross-bridge forms with release of d-alanine (DAP)

Gram-Negative Cell Wall Basic Structure

Outer membrane

- lipopolysaccharide (LPS): gives the negative charge

No teichoic acids!

Braun's lipoproteins: specific gram negative, attachment to peptidoglycan and membrane

Periplasmic space larger than gram positive.

Porin:

LPS (LipoPolySaccharide)

Has 3 components:

Lipid A: septic shock if released

Core polysaccharide: KDO

O side chain: Differentiates between strains.

E. coli O157:H7

causes outbreaks linked to spinach and salads (yearly); linked to cookie dough (2009) and Taco Bell (2006)

Mycobacteria

- Has a cell wall

- Uses haponoids

Mycolic acid: hard to gram stain

Acid fast staining: used with stain

M. leprae

M. tuberculosis

Atypical Bacteria:

Cannot be stained by Gram-stain procedures or are too small

Includes obligate intracellular pathogens

- Rickettsia spp. has a permeable membrane, pleomorphic

Chlamydia spp. does not synthesize ATP by itself (parasite)

Mycoplasma spp. do not have a cell wall

Cells that Lose a Cell Wall: Lysozyme vs. penicillin

Breaks vs inhibit

Lysozyme: only works with bacteria cell wall Beta 1,4

What are L-form Bacteria?

Able to make cell wall but choose not too to conserve energy.

Examples (not needed to remember):

Bacillus anthracis, Treponema pallidum, Mycobacterium tuberculosis, Helicobacter pylori, Rickettsia prowazekii, and Borrelia burgdorferi

Removal of the cell wall Protoplasts:

Gram-Positive

Removal of cell wall Spheroplast:

Gram-Negative

What are the Components Outside of Cell Wall?

Glycocalyx (polysaccharide)

surface attachment

Capsules

Protective advantages

- resistant to phagocytosis

-protect from desiccation

-exclude viruses and detergents

Slime layer: gliding motility

S-Layer:

Help with adhesion to surface, shape and rigidity.

Self-Assembling.

Protein or glycoprotein

Not seen in EUKARYOTES

Flagella:

Can be found in both eukaryotes and prokaryotes.

Function: Motility, attachment and Virulence.

Patters of flagellation:

monotrichous: one

lophotrichous: multiple one side

amphitrichous: both side single

peritrichous: every where.

Pili:

Sex pili used for conjugation

Type 4 pili used for twitching motility.

What are the flagella motility movements

Flagellar movement= Swarming, Swimming and Spirochete motility

What are the twitching motility movements

Done by the type 4 pili

Who causes the gliding motility movement?

S-Layer

Bacterial Flagellar Movement: Counterclockwise (CCW)

rotation causes forward motion (run)

Bacterial Flagellar Movement Clockwise rotation (CW)

disrupts run causing cell to stop and tumble

What are the components of the flagella?

Flagellum (motor force, propeller) DOES NOT USE ATP

Hook (Flexible joint)

Basal Body (Motor)

Different Motility by Flagella: Swarming

Moist surfaces, a type of group behavior

Peritrichous flagella

Pseudomonas species

Different Motility by Flagella: Spirochete Motility

Axial fibril

Flagella remain in periplasmic space

Corkscrew shape

Treponema species: cause of syph (image at the bottom)

Twitching and Gliding Motility

Slower than flagella movement

Requires a solid surface.

Twitching: attaches moves closer, spider man

Glides

Chemotaxis

Chemical attractants and chemical repellents bind chemoreceptors

Bacterial Endospore

Complex, dormant structure

Resistant to numerous environmental conditions

Includes: Calcium (Ca-DPA), Snall acid binding proteins (SASPS), dehydrated core, spore coat and exosporium protect.

ONLY MADE BY GRAM POSITIVE, not all make them though.

- By Bacillus, Clostridium and Sporosarcina (cocci)

Spores

Sporulation

from 8 up to 10 hours

Germination

Not a mode of replication= why? because we start with 1 spore and end with 1 spore.

Unable to go backwards, continuous mechanism

What makes the Archeal Membrane?

Are archaeal membranes Monolayer or Bilayer?

Isoprene Units (5-Carbon, branched)

Ether linkage rather than ester linkage.

- Ether more resistant than ester.

Monolayer structure for extreme thermophiles

Bilayer structure found in normal temp.

Are Bacteria membranes Monolayer or Bilayer?

Always bilayer

What are the components of archael Cell envelopes?

S- Layer (composed of proteins)

Capsules and Slime layers

Pseudomurein

Only archaea cell with outer membrane.....

Ignicoccus.

What is the Fungal Cell Wall made up of

Chitin polysaccharide: Cell wall made up of glucose.

What do you called a single celled Fingi and Multicellular fungi?

Yeast and Mold

What Makes Up the fungal Structure:

Thallus: Body -> Thallus is made up of Mycellium and Mycellium is made uo of hyphae.

Aseptate hyphae: Separation between nucleus and septum

Septated: No separation

Rhizopus stolonifer

black bread mold

Rhizopus-Burkholderia symbiosis

rice bacterium Burkholderia growing within Rhizopus produces rhizoxin

Aspergillus fumigatus

allergies and pathogen

What are Mycoses? Which specific group of the pathogenic fungai is the worst and the least harmful?

What is Opportunistic pathogenic Fungi?

Diseases caused by fungi

Systemic is the worst type of fungai (throughout the body)

Superficial: Least because its not in your immune system (skin)

Opportunistic: disease occurs when immune system is low

What is crytococosis?

Example of systemic mycosis.

Caused by Cryptococcus neoformans (invasive fungus)

Spread: Inhalation of spores from bird shit and contaminated soil

Immunocompromised: AIDs - Menigitiis

Immunocompetent: Mild or pneumonia-like sx's

What are Nosocominal Candidiasis? What are some diseases?

Obtained in Hospital setting.

Most infections involve skin or mucous membranes.

10% of infections come from candidasis.

C. Aures Mortality: 50 %

Candida albicans or C/ Glabrata: