KINGDOM MONERA (BACTERIA)

KINGDOM MONERA(BACTERIA)

What makes this kingdom unique?

Most abundant organisms on Earth Outnumber all other organisms combined More in a handful of dirt than the total number of

people who have ever lived

Characteristics

Prokaryotes: no nucleus or membrane-bound organelles

Characteristics

Smaller than smallest eukaryotes All are unicellular Now considered two kingdoms:

Archaebacteria and Eubacteria

prokaryotes

eukaryotes

smaller than

KINGDOM ARCHAEBACTERIA

Archae = ancient Evolution considers them the first organisms Can live where no others can

Types of Archaebacteria: methanogens

Convert CO2 into methane gas

O2 is poison to them Require anaerobic conditions

(i.e. sewage or swamp) Thrive in cow and human intestines

Types of Archaebacteria: thermoacidophiles

Love hot and acidic environment Many are chemosynthetic

volcanic vents hydrothermal vents

Types of Archaebacteria: extreme halophiles

Salt-loving Great Salt Lake and Dead Sea Use salt to generate ATP

KINGDOM EUBACTERIA

Classified in two ways: shape and stain 3 different shapes Unicellular or colonies

1. SPHERE-SHAPED: COCCUS

Diplococcus - two

Staphylococcus – clusters

Streptococcus – strings

2. ROD-SHAPED: BACILLUS

Diplobacillus - two Streptobacillus - strings

3. CORK SCREW: SPIRILLUM

REACTION TO STAIN

Gram stain used for classification Differing reaction based on cell wall

Cell membrane

(Phospholipid)

Peptidoglycan

(Protein + sugar)

Lipopolysaccharide

(Fat + sugar)Gram-negative Gram-positive

GRAM-POSITIVE EUBACTERIA

Absorb Gram stain and appear purple Simple cell wall antibiotics are effective

GRAM-NEGATIVE EUBACTERIA

Do not absorb Gram stain Absorb a secondary pink stain Complex cell wall antibiotics are ineffective

ALEXANDER FLEMING - 1928

Scottish bacteriologist Grew Staphylococcus bacteria in dish Contaminated by Penicillium mold Mold inhibited the bacteria 1st antibiotic

ANTIBIOTICS

Fight pathogens Interfere with formation of cell walls Many obtained from bacteria or fungi Others produced synthetically

NATURAL BODY DEFENSES

1. SKIN

2. MUCUS

3. TEARS

4. STOMACH ACID

5. LEUCOCYTES

6. ANTIBODIES

CELLULAR RESPIRATION

1. Obligate aerobes require oxygen

(i.e. Mycobacterium tuberculosis)

2. Facultative anaerobes can use oxygen

when available but do not require it

(i.e. Escherichia coli)

3. Obligate anaerobes cannot grow in

the presence of oxygen

(i.e. Clostridium tetani)

BACTERIA IN NATURE ~Photosynthesis

Cyanobacteria are photosynthetic O2

Availability of O2 advent of aerobic organisms

OscillatoriaNostoc

Anabaena

BACTERIA IN NATURE ~Nitrogen fixers

Rhizobacteria grow in roots of soybeans, alfalfa Convert atmospheric N2 into usable form for plants

BACTERIA IN NATURE ~Decomposers

Break down matter into simpler substances Nutrients released into the soil

BACTERIA IN NATURE ~Living Together (Symbioisis)

Mutualism: both organisms benefit Bacteria and Komodo dragons

Bacteria-laden saliva Mouth provides

habitat

BACTERIA IN NATURE ~Eutrophication

Excess phosphates and nitrates

Cyanobacteria thrive

Death and decomposition

Decomposition requires oxygen

Fish kill

BACTERIA and INDUSTRY ~Food Production

Ferment lactose in milk

sour cream, yogurt, and buttermilk Digest protein in milk

ricotta cheese and cottage cheese Fermentation

pickles and sauerkraut

BACTERIA and INDUSTRY ~Genetic engineering

Insert genes into bacteria Develop medical products

(i.e. synthetic insulin) Develop disease-resistant crops

(i.e. Bt corn)

Bt Corn Bt is a naturally-occurring soilborne bacterium that is found worldwide. This bacterium

produces crystal-like proteins that selectively kill specific groups of insects. Once the protein is eaten, insects stop feeding within two hours of a first bite and, if enough toxin is eaten, die within two or three days.

Plant geneticists create Bt corn by inserting selected exotic DNA into the corn plant's own DNA.

Bt corn improves European corn borer control.