1.3 Classification and Structure of Prokaryotic Cells

Nucleoid Region

Houses the circular DNA.

Fimbriae

Similar to cilia.

Bacteria in the Human Gut

Produce vitamin K and biotin which prevents the growth of harmful bacteria.

Chlamydia Trachomatis

Live inside the cells of the reproductive tract and cause a common STI.

Clostridium Tetani

Live outside of cells and produce toxins that cause tetanus.

Cocci

Spherical bacteria.

Streptococcus Pyogenes

Common pathogenic spherical bacteria.

Bacilli

Rod-shaped bacteria.

Escherichia Coli

Common pathogenic rod-shaped bacteria.

Spirilli

Spiral-shaped bacteria.

Treponema Pallidum

Common pathogenic spiral-shaped bacteria which causes syphilis.

Obligate Aerobes

Bacteria that use oxygen for metabolism.

Anaerobes

Bacteria that don't use oxygen for metabolism.

Obligate Anaerobes

Bacteria that cannot survive in an oxygen environment.

Facultative Anaerobes

Bacteria that can use oxygen for metabolism but usually toggle back and forth.

Aerotolerant Anaerobes

Bacteria that do not use oxygen, but can survive in an oxygen-present environment.

Bacterial Envelope

The cell wall and cell membrane together.

Gram Stain

Crystal violet and then safranin.

Gram-Positive Stain

Absorbs the crystal violet and produces a deep purple appearance.

Gram-Negative Stain

Does not absorb the crystal violet, but instead absorbs the safranin counterstain, producing a pink-red appearance.

Gram-Positive Bacteria

Thick peptidoglycan cell wall. 20-80nm

Lipoteichoic Acid

Another component of gram-positive cell walls, it is the substance that triggers the immune system.

Gram-Negative Bacteria

Thin peptidoglycan cell wall. 7-8nm

Lipopolysaccharides

Component of the gram-negative cell wall that triggers the immune system and inflammation more than lipoteichoic acid.

Periplasmic Space

Separate the cell membrane and cell wall in gram-negative bacteria.

Chemotaxis

The ability for cells to move toward or away from environmental chemicals such as food or host immune cells.

Flagella

Bacteria use these for chemotaxis.

Basal Body, Filament, Hook

Three components of flagella.

Filament

Hollow component of flagella composed of flagellin.

Basal Body

Complex structure that connects the flagella to the cytoplasmic membrane and it acts as the motor.

Hook

Connects the filament to the basal body so that as the basal body rotates, it exerts torque on the filament.

Prokaryotic DNA

Form a single circular chromosome containing the genetic material that is necessary for survival.

Plasmid

Contain the bacterial DNA that is not necessary for immediate survival but may encode for things that allow for antibiotic resistance.

Prokaryotic Ribosomes

30S and 50S

Prokaryotic ETC

Done in the cell membrane for the generation of ATP.

Aminoglycosides, Macrolides, Tetracyclines

Antibiotic classes that specifically target the prokaryotic ribosome.