Microbio: Bacteriology pt.2

Average size of prok. bacteria

0.2—>2.00 μm

3 basic shapes of bacteria

Spherical (round), Rod-Like, Spiral

Coccus (Spherical Bacterium)

Bacillus (Rod-Like)

Coccobacilli (shirt rod)

Comma shape/Vibrio

Spirillum pl.spirilla (rigid wavy)

Spirochete (Corkscrew shape)

Monomorphic (Most bacteria are monomorphic)

Bacteria that keep one consistent shape (don’t change form).

Pleomorphic

Bacteria that can change shape or size depending on conditions (environment, age, or stress).

Binary Fission

Division and Multiplication amongst Prokaryotes

Diplococcus

Groups of 2

Streptococcus

Chainlike formation

Tetrod

Group of 4; undetached cells

Sancinal

Group of 8; undetached cells

Staphylocacci

Group like function; Numerous groups

Appendage of Prok. cells

Outermost/external part

Hook

Short curved segment that links the filament to the basal body

Filament

Tail

Basal body

Attaches entire flagellum to the cell envelope

Atrichous Bacteria

Bacterial devoid without flagellum

Monotrichous

One flagellum (mono=1)

Amphitrichous

1 flagellum at both poles (Amphi= both poles)

Lophotrichous

Cluster of flagella at one end or both side (Lopho=cluster)

Peritrichous

Flagella are spread evenly around the cell (Peri=around)

Periplasmic/Endo-flagella

Flagella wraps around cell (associated with spirochete)

Pilus/pl. Pili

Short, fine, hair-like appendages. Not associated with locomotion (movement). (aprx.1000 pili per cell)

2 types of Pili

Attachment (Fimbriae) & Sex/Conjugation

Attachment (Fimbriae) Pili

Adhesion to surfaces

Sex/Conjugation Pili

Helps bacteria exchange genetic material (DNA) from cell A (Donor cell)—>B (Recipiant)

Cell envelope

All the layers that surround the cytoplasm of a bacterial cell (membrane(s) + cell wall).

Glycocalyx

Polysaccharide sugar coat lying outside of cell wall (2 types: Capsule & Slime layers)

Capsule

(Thick armor) Organized, not washed off easily and Protects bacteria from phagocytosis

Slime layer

(Sticky glue) Loose unorganized, easily washed off. Helps with attachment to surfaces

Phagocytosis

A process where a cell (phagocytes) engulfs and digests particles, such as bacteria.

Cell wall

A rigid layer that lies outside the plasma (cytoplasmic) membrane. Provides shape and protection for the cell. Site for antibiotics. peptidoglycan

Osmotic Lysis

Cell bursting from too much water (hypotonic)

Gram stain

To classify bacteria as Gram-positive or Gram-negative based on cell wall structure (peptidoglycan thickness).

Gram positive (q+)

Bacteria stained purple or blue; Thicker peptidoglycan layer; Teichoic acid & Lipoteichoic acid

Gram negative (q-)

Bacteria stained red or pink; Thinner peptidoglycan layer; Outer membrane

Periplasmic Space

Location between plasma membrane and the outer membrane fluid in the periplasmic space called periplasm.

Cytoplasm

Fluid of cell minus chromosome and plasmid. Contains everything else (ribosomes, inclusion bodies, minerals, amino acids, sugars, nutrients, proteins/enzymes, various chemicals).

Cytosol

Liquid (solution) of the cell/cytoplasm

Prok. Ribosomes

Associated with protein synthesis and are 70’s (Svedberg-unit of sedimentation)

Single coiled chromosome

Attached to inner lining of plasma membrane; Contains 4,000 genes avg.

Plasmid

Circular autonomously replicating DNA contain 5-100 genes, some which code for antibiotics, conjugation, and toxic production.

Inclusion bodies (Granules)

Reserve deposits in the cytoplasm of Prok. Bacteria. Non-living chemical compounds and byproducts of cellular metabolism.

Metachromatic Granules

Large inclusions, collectively known as Volutin, representing a reserve of Inorganic Phosphate used in Membrane Phospholipids, ATP and DNA/RNA synthesis.

Polysaccharide Granules

Starch and glycogen, both are polymer (chain) or glucose molecule

Lipid Inclusions

Indispensable (important) in the foundation of cell membrane (phospholipids)

Sulfur Granule

Important in synthesis of certain amino acids to form proteins.

Carboxysomes

Associated with bacteria that “fix carbon” such as photosynthetic bacteria and nitrogen fixing bacteria.

Magnetosomes

Inclusions of Iron Oxide (Fe₃O₄). Bacteria use magnetosome to move downward until they find an attachment site at the bottom of shallow lakes. (Acts as magnets)

Gas Vacuole

Provides buoyancy to bacteria to head to surface for photosynthesizing (autotrophs)

Lysozymes

An enzyme that breaks down bacterial cell walls by cutting the bonds in peptidoglycan (glycosidic). Found in tears, saliva, mucus, and sweat

Glycosidic Bonds

Connect glucose derivatives NAM and NAG

Transpeptide bridge

A short chain of amino acids that links one peptidoglycan chain (NAM-tetrapeptide) to another, giving the cell wall strength and rigidity.

Transpeptidase

Bacterial enzyme manufactures or synthesizes transpeptide.

What interferes with making of Transpeptidase?

Penicillin

What enzyme breaks apart penicillin?

Penicillinase