Micro Lecture Ch.1

Antony van Leeuwenhoek in 1674, used simple microscope, did first drawings

Robert Hooke, 1665 - used simple microscope to see bread mold

The idea that worms and other forms of life would arise from non-living material

• an Italian biologist and physician 
• in 1668 he challenged the spontaneous generation idea
• placed rotting meat in jar, proved worms found on rotting meat where from fly eggs, not from the rotting meat
• *He was REDI to prove it wrong!

• in 1749, he experimented with flasks containing various broths (made by soaking hay, chick, or other nutrient in water)
• gave rise to microorganisms even when flasks were boiled and sealed
• *believed brief boiling killed all organisms
• thus, his experiments supported the spontaneous generation idea
• *Cooking ham makes broths

• in 1776, the priest and animal physiologist obtained results that contradicted the experiments of Needham
• No bacteria appeared in his broths after boiling
• Differed from Needham 2 ways: Spallanzani boiled longer and sealed flasks ~ stayed clean unless flask cracked
• Argument continued, as heat supposedly destroys "vital force"
• *Father 'Spank-anzani'... spont gen wrong!

• French chemist, considered father of modern microbiology
• disproved spontaneous generation
• demonstrated air contains microorganisms
• demonstrated sterile broths in swan necked flasks remained sterile even when left open
• ended the arguments that unheated air or broths contained "vital force" for spontaneous generation
• Microbes actually settles in bends and sides of flasks
• *Pastor corrected spont gener

• An English physicist, proved Pasteur correct 
• Came to discovered there are some microorganisms that are heat resistant and not killed by boiling ~ from trying to boil hay broth that never sterilized

• A german botanist
• Along with Tyndall, they discovered endospores

heat resistant forms of bacteria

• We depend on microbes to convert N₂ into a form other organisms can use
• Supply of O₂ would be depleted w/o the production of oxygen during photosynthesis by not only plants but microorganisms
• Microorganisms are the only organisms that can degrade certain materials, such as cellulose
• Also play vital role in degrading materials in sewage and wastewater

• bacteria are used to degrade toxic pollutants and to synthesize a variety of different produces:
• ethanol-used as biofuel
• hydrogen gas-biofuel
• oils-possible biofuel
• insect toxins-used in insecticides
• Antibiotics
• amino acids- used as dietary supplements

a process in which bacteria is added to pollutants to hasten their decay

• the use of microbiological and biochemical techniques to solve practical problems
• depends on members of the microbial world
• Ex: led to genetically engineered plants resistant to many insects & diseases; easier production of meds such as insulin

• microbes that cause disease
• Ex: smallpox, plague, infuenza

• Changing lifestyles bring new opportunities for infectious agents to spread
• Some emerging diseases arise cause the infectious agents change abruptly & can infect new host

• In some cases, successful preventive measures become victims of their own success (vaccinations & parents misinfo) 
• pathogens become resistant to antimicrobial meds
• travelers and immigrants carry pathogens around the globe
• populations age or become susceptible to disease

respiratory infections and diarrheal diseases

• virus infects rodents, usually w/o causing disease
• infected animals shed virus in urine, feces, and saliva
• from there it's inhaled by humans
• only one of many emerging human diseases associated w small animals

• normal flora,
• characteristic communities populate all surfaces of the human body

• they grow rapidly on simple, inexpensive media
• growth reveals the same genetic, metabolic, and biochemical principles as higher organisms

• classifications which all living organisms can be classified
• there are 3 distinct domains:
• Bacteria, Archaea, and Eukarya

Is the highest level in classification above kingdom

• single celled organism consisting of a prokaryotic cell
• Cell type is characterized by lack of membrane-bound nucleus 
• Includes members of Bacteria and Archaea

region within a prokaryotic cell where the genetic material resides

• are prokaryotes ~ typically lacks membrane bound nucleus or any other membrane-bound organelles
• most have specific shapes, commonly cylindrical (rod-shaped), spherical (round) or spiral
• typically have rigid cell walls that contain peptidoglycan (a compound unique to bacteria)
• many can move using flagella
• typically multiply by binary fission
• found in all environments

• process in which one cell enlarges and then divides
• forms two cells, each generally identical to original

• Have a prokaryotic cell structure
• members of archaea are identical in appearance to bacteria, but are very different in the chemical composition
• Do Not have peptidoglycan in cell wall
• Multiply by binary fission
• Move primarily by flagella
• Many grow in extreme environments

• members are eukaryotes, meaning they are composed of one or more eukaryotic cells (true nucleus)
• have membrane-bound nucleus & other organelles, making them more complex than prokaryotes
• Microbial members include: Algae, fungi, protozoa

• a diverse group of photosynthetic eukaryotes
• multiple shapes & sizes
• can be single or multicellular
• use sunlight as energy source
• found near surface of either salt or fresh water
• cell walls are rigid
• Some are single celled, others are multicellular

• another diverse group of eukaryotes
• some are single celled yeasts, but many are large multicellular organisms such as molds and mushrooms
• gain their energy from degrading organic materials and are found wherever organic materials are present
• mostly live on land
• have rigid cell wall

• diverse group of microscopic, single-celled organisms
• live in both aquatic and terrestrial environments
• unlike algae & fungi, do not have rigid cell wall
• most ingest organic compounds as food
• are motile

• refers to a 2-word naming system
• First word in name indicates the genus, with the first letter capitalized
• Second indicates the species name, not capitalized
• Genus name commonly appreviated ( E. coli)
• Both words usually italicized or underlined

• they are not composed of cells (acellular infectious agents)
• By definition, an organism must be composed of one or more cells to be alive
• Non living agents are not microorganisms, so the term microbe is often used
• Includes viruses, viroids, and prions

• non-living microbe
• consist of either DNA or RNA packaged within a protein coat
• come in variety of shapes
• to multiply, must have host
• outside of host, viruses are inactive = obligate intracellular parasites
• can infect all forms of life

• consist of a single, short piece of RNA
• no protein coat
• multiply only inside cells
• cause a number of plant diseases
• no evidence showing they cause disease in humans
• obligate intracellular agents

• consist of only a abnormal form of cellular protein... NO DNA OR RNA
• are misfolded versions of normal cellular proteins found in brain
• acquired by eating prion-containing nervous tissues
• responsible for several fatal neurodegenerative diseases in humans and other animals (Mad Cow, Alzheimers & Parkinsons)

most pathogenic bacteria were identified

• Swine flu
• SARS
• TB
• Lyme disease
• Hep C
• AIDS
• Mad Cow
• West nile

• measles
• mumps
• whooping cough
• malaria
• plague
• yellow fever