Microbes Lecture 1a – Flashcards

- used in a manner that emphasizes the disagreeable reputation of microorganisms or microbes

- in health sciences it is just these disease producing microbes that we are concerned w/ - specifically the treatment and prevention of the diseases they cause BUT <1% and 99%

- photosynthetic

- food and oxygen-generating that is critical to life on Earth

- intestines for digestion; synthesis of some vitamins

- food

- produce vinegar, sauerkraut, pickles, alcohol, green olives, soy sauce, buttermilk, etc

- decompose to give

- fix N2

- mutual symbionts

- protect against disease (LAB)

- genetic engineering

- bacteria (primary focus) 

- archaea 

- fungi 

- protozoa

- viruses

- multicellular animal parasites

- algae

1. archaea

- prokaryotic (cell type)

- varies in composition; no peptidoglycan (cell wall)

- composed of branched carbon chains attached to glycerol by either linkage (membrane lipids)

- methionine (1st a.a. in protein synthesis)

- no antibiotic sensitivity

- lacking in rRNA loop and common arm of tRNA

2. bacteria

- prokaryotic (cell type)

- contains peptidoglycan (cell wall)

- composed of straight carbon chains attached to glycerol by either linkage (membrane lipids)

- formylmethionine (1st a.a. in protein synthesis)

- antibiotic sensitivity present

- rRNA loop and common arm of tRNA present

3. eukarya (eukaryotes) fungi

- eukaryotic (cell type)

- varies in composition; contains carbohydrates (cell wall)

- composed of straight carbon chains attached to glycerol by either linkage (membrane lipids)

- methionine (1st a.a. in protein synthesis)

- no antibiotic sensitivity

- lacking in rRNA loop

- common arm of tRNA present

1. archaea

- no nuclear envelope

- no membrane-enclosed organelles

- no peptidoglycan in cell wall

- some species are able to grow at temp. >100 d C

2. bacteria

- no nuclear envelope

- no membrane-enclosed organelles

- peptidoglycan in cell wall present

- not able to grow at temp. >100 deg celcius

3. eukarya (fungi, plantae, protozoa, algae)

- nuclear envelope present

- membrane-enclosed organelles present

- no peptidoglycan in cell wall

- not able to grow at temp. >100 d C

- no peptidoglycan in cell walls

- found in extreme environments but not always

- salt pans

- hot springs

- low pH areas

- tolerate or require high salt

- colour due to bacteriorhodopsin

- a photosynthetic pigment similar to rhodopsin in humans

- type of archae

- are heat loving

- yellowstone hot springs ex: pyrodictium tolerates 105 C

- produce methane by reducing CO2 (electrons fr. 4 H2)

- Nevada hot springs

- methanogens are strict anaerobes

- range fr. large multicellular types such as kelp (Ulva) - the large green, red and brown "leafy" things you would see on the sea shore to unicellular such as small, microscopic single cell organisms

- 7 has cellulose in cell walls

- abundant in moist/wet areas (produce, symbionts)

* photosynthetic eukaryotes w/a wide variety of shapes and both sexual and asexual reproductive forms

* unicellular composed of carbohydrates cell walls or cellulose

* produce O2 and carbohydrates utilized by other organisms

- unicellular algae

- Pfiesteria causes massive fish death along Atlantic coast

- also cause illness via toxins

- ex: Gymnodinium

- fish stop breathing

- humans irritates eyes & respiratory system

- ex: Alexandrium & Gonyaulax

- produce neurotoxin called saxitoxin

- all of these taxa form "blooms" (red tide) under certain conditions

- 10 to 30 mins after ingestion

- nausea, vomiting, diarrhea, abdominal pain, and tingling or burning lips, gums, tongue, face, neck, arms, legs and toes

- shortness of breath, dry mouth, a choking feeling, confused or slurred speech, and lack of coordination are also possible

- Diatoms

- unicellular algae 

- green algae: Clamydomonas, caulerpa: thallus 1 cell

- first report of neurological disease in Canada in 1987

- neurotoxin

- affected people who ate mussels

- diarrhea, memory loss

- for vaginal dilation

- others for Kombu or algin

- Laminaria japonica

- dulse = edible

- porphyra = nori (for sushi)

- some source of carrageenan, agar

- some poisonous

- 1655, beginning of cell theory w/ large eukaryotic cells

- theory that all living things are composed of cells

- 1632-1723

- first to observe smaller cells - 1673

- 1676 discovered bacteria

- proposed by a german zoologist named Theodore Schwann

- states that all living things are made up of cells

- Francesco Redi (1668)

- sealed vs. non-sealed then gauze jars

- John Needham (1745)

- heat nutrient fluids, pour, cover - then organisms

- reproduction of animalcules

- Lazzaro Spallanzani (1765)

- cover, heat, no organisms

- criticism: vital force stop by cover and heat

- Lavoisier

- showed life needs O2

- Virchow (1858)

- biogenesis

- demonstrated that spoilage was not due to spontaneous generation of microbes, but due to contamination by microbes present in the air

- to regenerate an organism that exists today

- to consider the very beginning of life

- Pasteur heated the wine at 56 C for 30mins

- killed bacteria but not the yeast

- still used today to:

- reduce spoilage

- increase shelf life

- kill potentially harmful bacteria

- demonstrated the link bet a specific germ and a specific disease

- noticed bacteria in the blood of cattle w/ anthrax - postulated bacteria may be cause of anthrax (cutaneous, GI, respiratory)

- validated the germ theory of disease

- established steps to prove certain microbes cause certain diseases

- introduced staining techniques for microscopy

- improved staining techniques

- introduced differential staining - more accurate identification of bacteria

- isolated the chemical w/c killed the bacteria: PENICILLIN

- named after the fungus: Penicillium chrysogenum

- single-celled, no nuclear memb., prokaryotic

- enclosed in cell walls composed of carbohydrate and protein called peptidoglycan

- prokaryotic, no peptidoglycan

- found in extreme environments

- divided into 3 main gr.

- methanogens: produce methane as a waste product fr. respiration

- halophiles: salt loving; live in salty environment such as great salt lake and the dead sea

- thermophiles: live in hot sulfurous water such as hot springs at yellowstone national park

- not known to cause disease in humans

- eukaryotic; cells have a distinct nucleus containing the cell's genetic material (DNA)

- surrounded by nuclear memb.

- unicellular or multicellular

- multicellular: mushrooms

- unicellular: yeasts

- can reproduce sexually or asexually

- dinoflagella toxins:

- fish stop breathing

- humans irritates eyes ; respiratory system

;

- a hypothetical process in which many scientists believed that some forms of life could arise spontaneously from nonliving matter