Microbiology 2: Microorganisms

ppt. by Robin D. Seamon

NEW There are 3 Domains

K

C

O

F

S

G

P

RANKING SYSTEM

For Your Information: in the ranking system…

Kingdom Monera

Kingdom Protista

Eubacteria

Archeaobacteria

C L A R I F I C A T I O N S T O H E L P

(Domain) Eukaryotes

One-celled

Microorganisms with a nucleus but no specialized tissues; one-celled, colony-forming, or multi-celled-need water

X “animal-like”“plant-like”“fungi-like”

D O M A I N A R C H A E A

Prokaryotes (no nucleus or organelles)

Separated from Bacteria Domain because of major differences in RNA; differences in cell wall

very old group- early life 3.5 bya

(Kingdom Monera)

REPRODUCTION

Binary fission single cell divides into two identical daughter cells

METABOLISM reflects Earth’s early atmosphere:

RESPIRATION: anaerobic- oxygen kills them

• Extremophiles live in extreme heat or cold

• Methanogens use H and CO release CH (methane) through respiration (in human/animal gut)

• Halophiles live in high concentrations of salt

• OTHER: oceans, soils, marshlands, human colon & navel

2 2

4

M O V E M E N T

Flagella: whip-like tails that move the organism

B A C T E R I A

Prokaryotes (no nucleus or organelles)

• very old group

• majority of prokaryotes today: 1 gram of soil has 2.5 billion bacteria

• Diverse

• Sometimes referred to as protists

(Kingdom Monera)

METABOLISM: various- photosynthesis, absorbs, parasite

RESPIRATION: varies

• anaerobic respiration (no oxygen)

• Aerobic respiration- uses oxygen

Aerobic respiration- uses oxygen

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M O V E M E N T

Flagella: whip-like tails that move the organism

REPRODUCTION: binary fission

1. Bacilli- rod-shaped

2. Cocci- spherical

3. Spirilla- long spiral

SHAPES

CLASSIFICATION:

1. Gram stain positive: huge cell membrane (staph, leprosy, TB)

2. Gram stain negative: thinner membrane(proteobacteria; nitrogen-fixers, clamdias, cyanobacteria, food poisoning)

HABITAT

• Most like warm & wet

• In dry & cold, some bacteria form endospores- genetic material in protective coat

• When conditions improve, endospore splits & bacteria become active again

• Scientists found bacteria inside an insect preserved in amber 30 million years ago; when endosperm was moistened, bacteria began to grow again!

http://archives.microbeworld.org/scientists/all_profiles/interview2.aspx

• food cheese, yogurt, buttermilk, sour cream:

• Breaks down milk sugar (lactose) into lactic acid- preserves & flavors

• Decomposers: recyclers

BACTERIA & ITS ROLES FOR US

• Nitrogen fixation: take N from air & turn it into a form plants can use; animals get N from plants

• Bioremediation: fight pollutionusing microorganisms to change harmful chemicals into harmless ones

• Clean up hazardous waste, industries, farms, cities

• Medicine antibiotics kill pathogenic bacteria & other microorganisms

• Genetic engineering: the manipulation of DNA in an organism by humans to create new or desired traits

• Insulin breaks down sugars in humans

• 1970’s we learned to put genes into bacteria that would make human insulin; Insulin separated from bacteria & given to diabetics

Desired human gene

(like insulin production)

D O M A I N E U K A R Y O T A

(nucleus- DNA & organelles)

THEORY- 1-2.1 billion years ago bacteria-like cyanobacteria started living inside larger cells in mutualism

- May have led to the first land plant

(Kingdom Protista)

METABOLISM: photosynthesis

RESPIRATION: aerobic

MOVEMENT: flagella, cilia, or blobby amoeba-like

TYPES: (Phylums)

1. Algae- plant-like

• Brown (kelp)

• Red (diatoms, seaweed)

• Green (most are land plants

2. Protozoa- animal-like)

3. Fungus-like (slime molds)

Photosynthesis

Heterotrophs or Parasites

Decomposers

Red algaeDeeper, tropical oceans, most seaweedsBrown algae

cool climates, on rocks or floating beds

Green algaeMost diverse, water, moist soil, trunks, inside organisms

(Kingdom Protista)

Seaweed: many celled algae

PhotosynthesisPRODUCER

PRODUCER

Phytoplankton: free-floating single-celled; produce much of the oxygen in world

(Kingdom Protista)

Photosynthesis

PRODUCER

Diatoms single-celled

• salt & freshwater

• Cell walls have glass-like silica

(Kingdom Protista)

Photosynthesis

PRODUCER

Dinoflagellates most single-celled

• flagella (spin through water)

• Most are producers, but some are consumers, decomposers, parasites

• Some bioluminesce

• ‘Red Tide’

(Kingdom Protista)

MULTI

ADVANCE

bioluminescenceBACK

red tideBACK

PRODUCER

Euglenoids: single celled

• Most freshwater

• Flagella

(Kingdom Protista)

MULTI

Phylum PROTOZOA (Kingdom Protista)

Heterotrophs

Phylum PROTOZOA“first animals”

(Kingdom Protista)

Heterotrophsor Parasites

1. amoeba: soft, jelly-like

• Eat other protists, bacteria

• Some parasites: amoebic dysentery

• Pseudopodia: stretches out pseudopod then cell flows into it; surrounds food, wastes excreted in reverse process

Food vacuole (digests food)

2. zooflagellates: wave flagella back & forth to move

• Water, other organisms

• Parasites: G. lamblia (in water, humans drink & get sick)

• Mutualism: live in gut of termites- digests cell wall of wood

ADVANCE

BACK

G. lamblia

BACK

Trichonympha: mutualism inside termite

3. Ciliates: complex protists

• Cilia beats 60 X per second

• For feeding, sweep food toward food passageway

paramecium

Slime molds thin, colorful globs of slime; cool moist woodlands; decompose wood

• Pseudopodia: food, movement

FUNGI-LIKE:

• Can live as individual cells until food & water is scarce, then they come together

• Live as a giant cell with many nuclei & single cytoplasm at one stage of life (1 meter across)

REPRODUCTION: When environment is stressful, they create stalk-like structures with rounded knobs: spores

• Spores can survive a long time without water

• When conditions improve, new slime molds develop

FUNGUS-LIKE

Slime molds

(Kingdom Protista)

FUNGI

(Yeast, mushroom, athletes foot)

(Kingdom Fungi)

Decomposers, parasites, mutualism (on roots of plants)

• Secrete digestive juices on or near food & absorbs dissolved particles

Hyphae: chains of cells, openings in cell walls to let cytoplasm through

Mycelium: hyphae growing together

FUNGI (Kingdom Fungi)

REPRODUCTION

1. Asexual parts of hyphae break off; or spores

2. Sexual special structures form to make sex cells; sex cells join to produce sexual spores

KINGDOM FUNGI:soil, decomposers, some parasites

1. Threadlike fungi: fuzzy mold

2. Sac fungi: largest groupyeast, powdery mildew, truffles, morels- make a sac (ascus) to sexually produce spores

(+) antibiotics(+) vitamins(+) food

(-) parasites(-) plant diseases

YEAST (Sac Fungi)

humans use for food (bread) & fermentation (beer & wine)

Use sugar for food & produce CO and alcohol as waste

Trapped bubbles of CO cause bread to rise

2

2

3. Club fungi: - mushrooms, sexual reproduction- bracket fungi, puffballs, smuts, rusts

Mycology: study of mushrooms

4. Imperfect fungi: asexual, mostly parasites(-) athletes’ foot(+) penicillium

(+) soy sauce(+) cheese(+) citric acid in sodas

LICHEN:

Mutualism: between a fungus & algae

Act like a new organism, so scientists give them their own scientific name

Most environments: dry, cold, rocks

Primary succession:

1. Lichens make acids that break down rocks, causing cracks

2. Rock sediments & dead lichens fill in cracks to make soil

Microbiology: Classification

ppt. by Robin D. Seamon

H I S T O R Y

Aristotle: (Greek philosopher 384-322 CE) classified animals based on method of reproduction

Taxonomy: group or categorize organisms

• Before 1700, there were multiple long names for new species with no rules in naming process

Carl Linnaeus (Swedish) 1735grouped organisms by shared physical characteristics

• wrote Systems Naturae

3 Kingdoms: 1. Mineral

2. Vegetable

3. Animal

Today naming is regulated by Nomenclature Codes allowing names to be divided into ranks:

Binomial nomenclature (genus & species) 1740’s

R A N K I N G S Y S T E M

• 1859 Darwin insisted classification should reflect genetic relatedness

• 1900 Emil Willi Henning: grouped organisms by inferred evolutionary relatedness

• Homologous structures; inherited from common ancestors, so were related

Phylogenetic taxonomy

• Cladistic system: 1960’s scientists started using DNA sequences to determine common ancestry IGNORING RANKS

• This new field is making changes & revisions in classification everyday.

• International Code of Phylogenetic Nomenclature (PhyloCode) is currently under development

Molecular PhylogeneticsC L A D E S Y S T E M

• 1990’s: New Grouping based on new discoveries in bacteria metabolism

1. Archaea

2. Bacteria

3. Eukaryota

D O M A I N S

Separated these 2

Includes Protists

Phylogenetic tree

H I S T O R Y O F C L A S S I F I C A T I O N

1735Linnaeus

1866Haeckel

1925Chatton

1938Copeland

1969Whittaker

1990Woesse

1998Cavalier-

Smith

2 Kingdoms 3 Kingdoms 2 Empires 4 Kingdoms 5 Kingdoms 3 Domains 6 Kingdoms

Mineral Prokaryote Monera Monera Bacteria Bacteria

Protist Protist Protist Archaea Protist

Eukaryote Eukaryote Chromista

Vegetable Plant Plant Plant Plant

Fungi Fungi

Animal Animal Animal Animal Animal

To apply Darwin to

Microscopic organisms

To show having

nucleus or not

To show evolutionary

history of life

1969 Wittaker: 5 Kingdoms

Protists

Monera

Plants AnimalsFungi

Prokaryotes: Eubacteria &

Archeobacteria

Eukaryotes

Absorb & photosynthesize

Asexual Reproduction

Absorb & photosynthesize

Asexual & Sexual Reproduction

Photosynthesize

Asexual & Sexual Reproduction

Non-mobile

Ingest

Asexual & Sexual Reproduction

mobile

Absorb

Sexual Reproduction

Non-mobile

1990 Woese: 3 Domains

Eukaryotes

PlantsAnimals

Fungi

Protists

Photosynthesize

Asexual & Sexual Reproduction

Non-mobile

Absorb

Sexual Reproduction

Non-mobile

Archaea CBacteriaMonera Monera

Absorb & photosynethsize

Aerobic respiration

Asexual & Sexual Reproduction

Various metabolism: photosynthesis, fermentation,

Methanogenesis respiration

Asexual & Sexual Reproduction

Various metabolism: photosynthesis, fermentation,

Anaerobic & aerobic respiration

Asexual & Sexual Reproduction

Ingest

Asexual & Sexual Reproduction

mobile

NO NUCLEUS

NO NUCLEUS

NUCLEUS

DOMAIN DOMAIN DOMAIN

Bacteria Archaea

Plants Protist

Animal

Fungi

Tree of life Web Project

Tolweb.org