bacteria ecology

Motility

very limited options bc of cell wall

Majority are nonmotil

How do bacteria move

Can use pili to walk on some surfaces

Most common is via flagella

Use protein gradients not ATP

Phototaxis

Moving in response to light

Chemotaxis

Move in response to chemicals (like smelling)

Monotrichous

One flagella one end

Lophotrichous

Multiple flagella on one end

Peritrichous

Flagella on all sides

Amphitrichous

1 Flagella on either end

Perry plasmic space

Can contain a Perry plasmic flagella which has the flagella in the inside of the cell

Only in spirillias

Defenses

Endospores

Glycocalyx

Biofilms

Toxins

Endospores

Most resistant life form in existence

Inside of cell

Form around cells DNA when bacteria is under extreme stress

Only seen in bacillus, lactobacillus, and clostridium spp

Metabolically inactive

Glycocalyx

Secretions that surround a single cell

On the outside like “capsule”

Prevents phagocytosis

Biofilms

Secretions that surround a community of cells

Ex plaque on your teeth (protects bacteria in ur mouth from saliva that would destroy it)

Protects cell from water loss, chemical disinfectants, and antibiotics

Have to be mechanically removed

Toxins

Cells can produce compounds that produce specific symptoms

Endotoxin

Exotoxins= botulinum toxin (Botox)

Antibiotics!!!

Bacterial immune system

CRISP-Cas9

Clustered Regulatory Interspaced Short Palindromic Repeats

Group of genes that were discovered in streptococcus pyrogonies

Allows bacteria to break down DNA of a virus so it cannot reproduce

Who discovered and won a Nobel prize

Dr. Charpentier and Dr. Doudna 2020

Food

Sugar→ glucose→ ATP

strategies to find sugar

Photosynthesis/photoautotrophs

Chemoheterotrophs

Chemoautotrophs

Photosynthesis/photoautotrophs

Pigments that absorb UV radiation

Use light(ATP) and CO2 to make sugar

Cyanobacteria

Chemoheterotroph

HUMANS!

We get our food(sugar and fat) from other organisms rather than making its ourselves

Saprobes= decomposers

Secrete enzymes breakdown food outside of the cell so that they can absorb it

Chemoautotrophs

Inorganic compounds to fuel sugar production

ATP

Adenosine Triphosphate

Cellular energy currency made by the breakdown of other molecules (carbohydrates, fats)

Aerobic respiration

Most efficient

Uses oxygen to generate ATP

obligate aerobes

facultative anaerobes (doesn’t NEED O2)

1 glucose will equal 6 CO2

36 ATP/1 glucose