chapter 1-5 microbiology (fall semester 2023)

introduction to microbiology, microscopes, microbes

biology

study of living organism

microbiology

study of microbes

microbes

extremely small (microscopic) living AND non-living organisms

living microbes are

cellular microbes or microorganism

examples of living microbes

viroids, prions, viruses

microorganisms are found

everywhere (aka ubiquitous)

germs

microbes that cause disease

pathogens

term for disease causing microbes

non-pathogens

term for microbes that DONT cause disease

opportunistic pathogens

microbes that may cause disease, but are mainly awaiting for the opportunity to

2 categories of disease caused by pathogens

infectious disease and microbial intoxication

who produces much of our oxygen

photosynthetic algae and bacteria (such as cyanobacteria)

decomposition

microorganisms work to decompose waste and dead organisms

microbe uses

decomposition, elemental cycles, digestion (inside of intestinal tract), industries, genetic engineering

Anton van Leewenhoek

father of microbio, not a trained scientist, animalcules, single lens microscope user

Louis Pasteur

french chemist, fermentation, yeast fermentation into alcohol, bacteria fermentation into vinegar, pasteurization, rabies + anthrax vaccine

germ theory disease

Louis Pastuer led the hypothesis that microorganisms cause disease

pasteurization

milk is heated to a specific temperature for a set period of time to kills harmful bacteria

Robert Koch

discovered cause of anthrax

koch’s postulate

step’s that relate a specific microbe to a specific disease, helped prove germ theory

cause of anthrax

bacillus anthracis

exceptions to koch’s postulate

cannot be cultured, species specificity, synergistic infection (needs microbes to work)

microscopes

an optical instrument that is used to observe objects so small that they cannot be seen with the unaided human eye.

resolving power/resolution

each optical instrument has a limit as to what can be seen using that instrument

resolving power of the unaided human eye

approximately 0.2 mm.

earliest simple microscope

a tube with the plate for the object at one end and a magnifying lens at the other end (the magnification was usually less than 10X the original size)

compound microscope

contains more than one magnifying lens

a compound light microscope

visible light is the source of illumination

This microscope contains two magnifying lens systems

the eyepiece/the ocular lens AND the objective lens

eyepiece/ocular lens

usually X10

the objective len

X4, X10, X40, and X100 are the four most common

how to calculate total magnification

multiply the ocular lens magnification with the objective lens magnification

fluorescence microscopy

neon uv colored, organisms absorb dye to view

phase contrast microscopy

gray colored, best way to observe LIVING matter

darkfield microscopy

no light at all, helpful to view thin and small microbes

electron microscopy

never uses staining, EM can magnify 2000x, very expensive

two types of electron microscopes

transmission and scanner

transmission electron microscope

2D

scanner electron microscope

3D, meant to view staph or strep

cell

unit of any living organism because it exhibits the basic characteristics of life

2 categories of cells

eucaryotic and procaryotic

Prokaryotes

NO membrane bound organelles, capsule and/or cell membrane

Eukaryotes

contain a "true" nucleus, membrane bound organelles

Viruses, prions, viroids are

acellular

Cell wall

seen in plant cells only (eukaryote), meant for shape/structure

Flagella and cilia

contain microtubules

Flagella

string-like appendage meant for movement, example \= sperm

Cilia

hair-like structure (found on protozoa and certain body cells)

Is eukaryote or prokaryote smaller?

prokaryotic is about 10x smaller than eukaryotic

Binary fission

how prokaryotic cells reproduce, one cell splits in half to become two daughter cells

Prokaryotic cytoplasmic particles

mainly ribosomes, 70s

Peptidoglycan

only found in bacteria, gram pos+ bacteria have thicker layer, gram neg- have thinner layer

Mitochondria

has its own ribosome (70s) and DNA from the mother, chemical powerhouse that drives cellular function

Glycocalyx

slimy material produce by the cell membrane

2 types of glycocalyx

slime layer (loosely connected to cell wall) or capsule (highly organized and firmly connected)

Pili (also called fimbriae)

hair-like structures, most often observed on Gram-negative bacteria

What is pili made of

composed of polymerized protein molecules called pilin

Pili and flagella difference

pili are thinner than flagella, have a rigid structure and are not associated with motility

Bacteria and Pili

enable bacteria to anchor themselves to surfaces, some bacteria possess a sex pilus for conjugation

Spores (Endospores)

A few genera (e.g., Bacillus and Clostridium) are capable of forming thick-walled spores as a means of survival

Sporulation

process of spore formation (repackaging a copy of DNA in a new form that contains little water) NOTE

Spores resistant

have been shown to survive for many years and are resistant to heat, cold, drying, and most chemicals

Germination

return to vegetative state by weakening a spore, then having a nutritious environment (if no autoclave, one may have to do this to destroy)

Taxonomy

the science of classification of living organisms (consists of classification, nomenclature, and identification)

Classification

the arrangement of organisms into groups (known as taxa).

King David Came Over for Good Spaghetti

K for Kingdom, D for Division, C for Class, O for Order, F for Family, G for Genus and S for species

Binomial system

“two names” aka what the science of taxonomy was established based on

How does the binomial system work?

each organism is given 2 names - genus and the specific epithet. Combined, both names constitute the species

Bional system example

Escherichia coli; Escherichia is the genus and coli is the specific epithet (e.g., E for Escherichia).

Fungi Classification

Kingdom Fungi

Plant Classification

Kingdom Plantae

Bacteria and Archaea

kingdom procaryotae

Algae and Protozoa

Kingdom protista

Animals Classification

Kingdom Animalia

Archaea and bacteria

prokaryotic

Algae, protozoa, fungi

eukaryotic

Five Kingdom System of Classification

* Kingdom: Animalia

Key Characteristics: Multicellular, heterotrophic, eukaryotic

Examples: Humans, dogs, birds

* Kingdom: Plantae

Key Characteristics: Multicellular, autotrophic, eukaryotic

Examples: Trees, flowers, grass

* Kingdom: Fungi

Key Characteristics: Multicellular or unicellular, heterotrophic, eukaryotic

Examples: Mushrooms, yeasts, molds

* Kingdom: Protista

Key Characteristics: Mostly unicellular, eukaryotic

Examples: Amoeba, algae, paramecium

* Kingdom: Procaryotae

Key Characteristics: Unicellular, prokaryotic

Examples: Bacteria, cyanobacteria

​Microbes

truly cellular (bacteria, archaea, algae, protozoa, and fungi) + acellular (viruses, viroids, and prions)

Cellular microbes (microorganisms)

prokaryotic (bacteria and archaea) +

eukaryotic (algae, protozoa, and fungi)

Viruses, viroids and prions

acellular microbes or infectious particles.

Types of Microorganisms

bacteria, archaea, fungi, protozoa, algae, virus

Bacteria

unicellular, prokaryotes

Bacteria shapes

bacillus \= rod; spiral; or coccus \= spherical or ovoid

What can bacteria do?

can form pairs, chains, clusters (usually species specific), enclosed in peptidoglycan cell wall, many move using appendages called flagella

Archaea

unicellular, prokaryotes, NO peptidoglycans in cell wall; found in extreme environments, NO pathogens

Fungi

kingdom of unicellular or multicellular eukaryotes (unicellular yeasts, multicellular mold and mushrooms)

Protozoa

unicellular protists; eukaryotes, move by pseudopods, flagella, or cilia

Protozoa example

amebae

Algae

photosynthetic eukaryotes; unicellular or multicellular

Viruses

different, super small (electron microscope), cellular (acellular)

What do viruses contain

DNA or RNA (either or NOT both)

What turns a virus into something living

Viruses can only reproduce by using the cellular machinery of other organisms; therefore only considered living when they infect

Multicellular Animal Parasites

strictly microorganisms, medically important eukaryotes, microscopic during some stages of life cycle

Example of Multicellular Animal Parasites

helminthes (worms)

Virions

complete virus particles

Viruses infect what?

humans, animals, plants, fungi, protozoa, algae and bacterial cells.

oncogenic viruses or oncoviruses

cause specific types of cancer

a typical virion consists

a genome of either DNA RNA, surrounded by a capsid

Capsid

protein coat which is composed of protein units called capsomeres