Micro Chapter 3 - Bacteria Pt. 1

What are two types of bacterial shapes that are similar to fungi?

Filamentous and complex

Filamentous shape

Grows like hair as the cells elongate, make hyphae and then mycelium, similar to fungi

Hyphae

Hair

Mycelium

Ponytail of hair

What are two examples of bacteria that grow filamentous?

Cyanobacteria and Streptomyces

What are "myc" and "myx" generally associated with?

Fungi

What does the bacteria Streptomyces include lettering that is generally found in fungi?

Because they look like fungus

Cyanobacteria was improperly called this before realizing it was a bacteria

Blue-green algae

Complex shape

Create fruiting bodies (located where the spore is, generally at top portion, so determines color of an organism), similar to fungi

Example of bacteria that has complex shape?

Myxococcus

Myxococcus

Works as a predator to kill other cells including eukaryotes

What is bacterial arrangement determined by?

the plane of division and separation or not

What is the shape and arrangement if you have staphylococci?

Shape = cocci (circles) and arrangement = staphylococci (cluster)

What is the smallest bacteria?

Mycoplasma

Mycoplasma

Doesn't have a cell wall, so usually grows inside other cells

What bacteria shape is typically seen as the average size and give an example

Rods, E. coli

What is the average size of bacteria?

10^-6 micrometers

What is an example of a very large bacteria?

Epulopiscium fishelsoni

Epulopiscium fishelsoni

A type of cyanobacteria, prokaryote that is larger than a eukaryote (not all prok are smaller)

Paramecium

A eukaryotic ciliate

Cilia

Hair-like extensions that beat together in the same direction to move water

Thiomargarita magnifica

Bacteria that is much bigger than 0.5mm, magnifica = huge, they found it, studied, went back to find again and it was gone

Size-shape relationship

There is a limit to how big cells can get - the bigger you get, the more likely you are to be eaten, it's harder to absorb nutrients, and harder to push waste out, so the metabolism slows down and waste accumulates

What is the order from smallest to largest size of Escherichia coli, Bacillus megaterium, Haemophilus influenzae, Oscillatoria, and Streptococcus pneumoniae?

Haemophilus influenzae (smallest), Streptococcus pneumoniae, Escherichia coli, Bacillus megaterium, and Oscillatoria (largest)

Which bacteria tend to be the largest?

Cyanobacterium (photosynthetic) species

Bacillus megaterium shape

Rod

Streptococcus pneumoniae

Chain of cocci that causes pneumonia

Haemophilus influenzae

Doesn't cause the flu because it's a bacteria, not a virus, but it does cause meningitis when present with the flu because it finds the immune system is busy fighting the flu and comes in as a secondary infection to cause harm

Oscillatoria

cyanobacterium and photosynthesizes

The rate at which nutrients and waste products move in and out of a cell is generally

inversely proportional to cell size (the bigger the cell gets, the slower and less efficient exchange becomes)

What does the transport rate depend on?

Membrane surface area available in comparison to cell volume

Why do larger cells have slower transport rates?

Larger cells have more volume to support but relatively less membrane surface area for exchange.

What does membrane surface area represent in cell transport?

The number of sites (doors) where nutrients and wastes can cross the cell membrane.

Is there a limit to sizing of bacteria?

Yes

Which shape of bacteria is the most efficient?

Rods are more efficient than cocci

What SA/V ratio is the most effective at nutrient exchange?

A larger one/more collision surface area

Collision surface area

Amount of cell membrane available for particles to physically bump into and interact with during diffusion across the membrane

What size of cells are more effective transporters?

Small cells because they have a high SA:V ratio, allowing faster nutrient and waste movement.

As cell size increases, the SA:V ratio

decreases, making transport less effective

Diffusion

Molecules move from high to low concentration

SA/V ratio

3/r

SA of a sphere

4πr^2

Volume of a sphere

4/3πr^3

What is a capsule for and how do bacteria with one look?

Protection and bacteria with a capsule look wet because it holds water to protect itself

What is the S layer for

Protection

The outer membrane is also known as

LPS

Which type of bacteria have an outer membrane

Gram negative

What is peptidoglycan made of?

Peptides and sugars (glucose)

Did mitochondria come from a gram + or gram -

Gram negative because it has 2 membranes

What is the cell envelope?

Encompasses all the cell layers outside of the cytoplasm

Inclusions

Help with movement

Cytoskeletal proteins

Help give shape to the cell or help with a function or reaction in the cell

Periplasmic space

The site of nutrient degradation and protein transport

Are bacteria haploid or diploid? What does this mean?

haploid (one copy of each chromosome)

Are humans haploid or diploid? What does this mean?

Diploid (2 copies of each chromosome)

What parts of the cell envelope does a gram positive bacteria have?

Cell membrane --> peptidoglycan

What parts of the cell envelope does a gram negative bacteria have?

Cell membrane --> outer membrane, including peptidoglycan in the middle

What are the bacterial cytoplasmic structures?

Cytoskeleton, intracytoplasmic membranes, inclusions, ribosomes, nucleoid, and plasmids

What do ribosomes do?

Protein synthesis (translation)

What does the bacterial nucleoid contain?

Chromosome

What are the cytoskeleton molecules?

FtsZ, MreB, and CreS

FtsZ is a protein found in

Many bacteria

What is the function of FtsZ?

Plays a role in division/replication, function is to find the center of cell to help bacteria equally distribute content from one cell --> 2 cells

What do humans have instead of FtsZ?

Tubulin

What color is FtsZ?

Red

MreB is a protein found in

Many rods

What is the function of MreB?

Maintains rod shape

What do humans have instead of MreB?

Actin

What color is MreB?

Green

CreS is short for

Crescentin

What is the function of CreS?

Gives vibrio its curve shape by assembling on the inner side of the cell

What do humans have instead of CreS?

Intermediate filament

What color is CreS?

Pink

Storage inclusions

Save nutrients and stuff for later use (not the same as an inclusion)

Glycogen

Storage of glucose

Glucose

6C molecule, sugar, needed for glycolysis, base of 12C skeleton

PHB (poly-beta-hydroxybutyrate)

Storage of carbon

Polyphosphate Granules

Storage of phosphate

What is phosphate needed for?

Backbone of DNA, unit for ATP

Cyanophycin Granules

Storage of amino acids, specifically nitrogen if not doing translation

Sulfur Globules

Storage of elemental sulfur

What is sulfur needed for?

aa and coenzymes (Acetyl-CoA)

What are the two types of inclusions and what are they used for?

Gas vacuoles and Magnetosomes for movement

Where are the inclusions located?

In the cytoplasm

Gas vacuoles

Adjust buoyancy of the cell in water - tubes fill with gas to allow cell to float or remove gas to sink

Magnetosomes

Dependent on cytoskeletal MamK protein - magnetic particles recognize magnetic field to find the center of the Earth or bottom of the ocean

What is the model bacteria for magnetosomes?

Magnetospirillum gryphiswaldense

Plasmids

Extrachromosomal DNA that is independent/exists and replicates separately from the chromosome, gets passed on from mother to daughter cells

What kind of information do plasmids contain?

Non-essential genes that often provide survival advantages in adverse environments (such as antibiotic resistance)

Episomes

A specialized type of plasmid that can integrate into the chromosome

Conjugate plasmids

Allows bacteria to share genetic info through horizontal gene transfer

R plasmids

Contain genetic information for antibiotic resistance

Virulence plasmids

Provides genetic information that allows the production of virulence factors such as toxins (how tough + how much damage you can do)

Col plasmids

Col = collision, provides the ability to produce bacteriocins, proteins that help kill neighboring bacteria.

What is an example of how plasmids are used in research/biotechnology?

Use plasmids to make insulin in bacteria and give it other humans

The plasma membrane is also known as the

cell membrane

The cell membrane is a

requirement for living organisms

What does the plasma membrane do?

Separate outside from inside, encompasses the cytoplasm, has a selectively permeable barrier, interacts with external environment to detect and respond to chemicals in surrounding, transport, and metabolic processes

What do things that need to cross the plasma membrane go through?

Protein transporter

How does waste get shipped outside of a cell?

Transmembrane proteins