Microbiology Chapter 1

what is microbiology?

the study of small life

• Micro- small

• Bio- life

• Logy- study

HUMAN USES OF MICROORGANISMS (3)

biotechnology, genetic engineering, bioremediation

what are the three areas of food microbiology

food safety, food spoilage, and food fermentation

what is food safety

effects food to make humans sick due to pathogens and may not by physically apparent (bad microorganisms)

what microorganisms does food safety include

• Bacteria, fungi, protozoa, parasites, viruses

what is food spoilage

mainly effects quality of food product; does not have ability to cause sickness due to not being pathogens; may not cause illness to us but instead cause spoilage to the food product (bad smell, flavor) (the ugly- make food ugly)

what microorganisms does food spoilage include

• bacteria

  • fungi

what is food fermentation

like yeast, bacteria found in yogurt

what microorganisms are involved in food fermentation

bacteria and fungi

areas of work for food microbiologist?

wide variety and range of possible work area

○ Quality control (QC) and quality assurance (QA)

○ Food safety- make sure food is safe (life international trading)

○ Food regulations

○ Analytical labs

○ R&D

○ Teaching and research

in microorganism terms, first we started with —> then we got

prokaryotes which evolved to give us eukaryotes

what are the 2 major cell lines

prokaryotes and eukaryotes

prokaryotes are defined by what

no nucleus

what microorganism is always a prokaryote

bacteria

bacteria are

single celled

eukaryotes are characterized by what

having a true nucleus

eukaryotes include

algae

fungi

protozoa

helminths

algae are

photosynthetic organisms

fungi are

Microscopic like mold and yeast

Macroscopic like mushrooms and puffballs

protozoa are

animal like, mostly single cells

helminths are aka

worms

prokaryotes size and components

smaller than eukaryotes and no nucleus or organelles

have ribosomes, chromosomes, cell wall, and cell membrane

eukaryotes size and characteristics are

bigger than prokaryotes and more complex

have organelles like mitochondria

have nucleus

can be unicellular or multicellular

what are viruses

tiny, noncellular, parasidic things

viruses are not considere what? why?

not considered alive because they cannot survive on their own. They need a host to rely on

why do we classify viruses with microbes?

very tiny and sometimes smaller than bacteria and are microscopic and cause disease

viruses are not made of

cells! cannot replicate on their own!! They are made of a nuclear envelope to encompass their genetic material

what are the 6 types if microbes

bacteria

fungi

algea

virus

protozoa

helminths

what size range do microbes belong in

10nm to 10mm

• small ones (NM) are usually viruses

• bacteria usually micrometers

• eukaryotes tend to be the larger ones

microbes are involved in what that is key to nutrient and energy flow of ecosystem

photosynthesis and decomposition

photosynthesis and which microbes an do it

light fueled conversion of carbon dioxide to organic matter

• algea

• some bacteria

decomposition

breakdown of dead matter and waste into simpler compounds

microbial lifestyles (3)

• most live freely (not bound to a host)

• often share nutrients and habitats with other organism

• parasites live on or in Host organism

microbes that live freely means what

not bound to a host

• Relative harmless

• Often beneficial

• Some EVEN ESSENTIAL

parasites do what to host

Usually cause damage

Cause Infection, disease

what are pathogens

microbes that do harm (to humans or animals)

NOW WE LOOK AT HISTORY OF MICROBIOLOGY

in the past 300 years, main 3 prominent discoveries made in microbiology

Microscopy

Scientific method

Microbiology lab techniques

Created first microscope in 1590

Hans and Zacharias Janssen

First to observe living microbes in 1675

Antoine Van Leeuwenhoek

made single lens magnified up to 300x

Antoine Van Leeuwenhoek

what were the 4 major questions scientist wanted to know?

Is spontaneous generation of microbial life possible?

What causes fermentation?

What causes disease?

How can we prevent infection and disease?

what was the idea of spontaneous generation

Early belief some life forms could arise from vital forces in nonliving or decomposing matter

○ Flies from manure

○ Mushrooms on rotten log

○ Maggots on meat

who disproved spontaneous generation?

Louis Pasteur- THEORY OF BIOGENESIS- the idea that living things can only arise from other living things

theory of biogenesis

the idea that living things can only arise from other living things

francesco redi experiment about spontaneous generation

Decaying meat isolated from flies-----> maggots never developed

Meat exposed to flies---> soon infested

so saw that maggots were from the flies and not the mean

scientist began to doubt spontaneous generation

louis pasteur experiment concerning spontaneous generation

proved it NOT TRUE

Used swan-necked flask that remained upright, no microbial growth appeared When flask tilted, dust from the neck bend seeped back into the flask and clouded the infusion with microbes within a day

what is the scientific method

-A scientific approach to explain how and why an observed phenomenon occurs

-Uses hypothesis to predict what will happen under known conditions

-A lengthy process of experimentation, analysis, and testing

-Result either support or refute hypothesis

hypothesis

possible explanation that can be supported or refuted by observation and experimentation

goes from Hypothesis--> theory----> law

what are the 6 basic steps of the scientific method

1. Observation leads to question

2. Question generates hypothesis

3. Hypothesis tested through experiment

4. Accept, reject, or modify hypothesis based on results

5. Publish results

6.repeat

what did edward jenner do?

used the scientific method in disease control

Experiment 1

- Took scraping from cowpox blisters on a milk maid hand

- Inoculated the scrapings into a boy who had NOT had smallpox

- The boy developed minor symptoms but remained healthy

Experiment 2

- A few weeks later the child was exposed twice to pus from active smallpox lesion

- He did NOT acquire smallpox and appeared to have immune protection

what did joseph lister do (3)

-introduced aseptic techniques to reduce microbes in medical settings and prevent wound infection techniques

-chemical disinfection of hands prior to surgery

-use of heat for sterilization

what is the germ theory of disease

The idea that many diseases are caused by growth of microbes in the body- not sins, bad character, poverty, etc

what did robert koch study

causative agents of disease

how did louis pasteur contribute to the germ theory (4)

-Showed microbes caused fermentation and spoilage

- Disproved spontaneous generation of microorganisms

- Developed pasteurization

- Demonstrated what is now known as Germ Theory of Disease

what are contributions of Robert Koch (7)

•Simple staining techniques

•First photomicrograph of bacteria (both in and outside of diseased tissue)

•Techniques for estimating CFU/mL

•Use of steam to sterilize media

•Use of Petri dishes

•Techniques to transfer bacteria

•Bacteria as distinct species

what did robert koch contribute to the germ theory

Established Koch's postulates- series of experiments to determine if a pathogen is the cause of a disease - -Identified cause of anthrax, TB, and cholera

THE POSTULATES TIED THE DISEASE TO THE CAUSE

what are koch’s postulates

series of experiments to determine if a pathogen is the cause of a disease

what are Koch’s postulates (like the 3 specific ones)

1. Agent must be isolated in pure culture and grown outside the host

2.When agent is introduced into a healthy, susceptible host, the host must/should get the disease

3. Same agent must be found in the diseased experiment host

what is taxonomy

how we organize, classify, and name living things

what are the levels of classification (8)

domain (archaea, bacteria, and eukarya

kingdom

phylum or division

class

order

family

genus

species

who fathered taxonomy

carl von linne

what are the 3 concerns of taxonomy? (parts it focuses on)

classification, nomenclature, and identification

Classification

orderly arrangement of organisms into groups

Nomenclature

assigned names

Identification

determining and recording organism traits in order to place into taxonomic schemes

method of classification (phenotype) encompasses what?

***Analyze observable and biochemical properties

Observable characteristics

○ Size

○ Shape

○ Staining characteristics

Biochemical properties

○ Ability to ferment carbs

○ Carbon source used for growth

○ Enzymes

○ Biotyping

○ Serotyping

○ Phage typing

what does analitic methods of classification encompass?

***Analyze cell structure

Whole cell lipid analysis

Cell wall fatty-acid analysis

Whole cell protein analysis via mass spectroscopy

Enzyme and electrophoresis

what does genotyping method of classification encompass?

*look at the genetic information

*most accurate methods

DNA-DNA hybridization

Nucleic acid sequence analysis

Whole genome sequencing analysis

Plasmid analysis

Ribotyping

how are things names scientifically

using binomial nomenclature

BINOMIAL (SCIENTIFIC) NOMENCLATURE

Gives each microbe 2 names

-Genus- capitalized

- Species- lowercase

Both italicized (preferred) or underlined (when handwritten)

staphylococcus aureus (S. aureus)

- Listeria monocytogenes (L. monocytogenes)

- Salmonella enterica (S. enterica)

ALWAYS GIVE FULL NAME FIRST, THEN CAN USE ABBREVIATION IF MENTIONED AGAIN

They are named according to who discovered them, how the microbe looks, or the disease it causes

what two things do we use to explain ORIGIN AND EVOLUTION OF MICROBES

phylogeny and evolution

Phylogeny

○ Natural relatedness between groups of organisms

Evolution

-All new species originate from preexisting species

-Closely related organisms have similar features bc they evolved from common ancestral forms

evolution ___________ progresses toward greater complexiity

usually

what are the 5 kingdoms

Monerans

• Prokaryotes, unicellular

Protists

• Eukaryotes, mostly unicellular, can be photosynthetic or feed on others

Plants

• Eukaryotes, multicellular, cell walls, photosynthesis

Fungi

• Eukaryotes, multicellular, cell walls, NOT photosynthetic

Animals

• Eukaryotes, multicellular, NO cell walls, NOT photosynthetic

monerans (characteristics)

a. Prokaryotes, unicellular

protist charcateristics

a. Eukaryotes, mostly unicellular, can be photosynthetic or feed on others

Plants characteristics

Eukaryotes, multicellular, cell walls, photosynthesis

fungi characteristics

Eukaryotes, multicellular, cell walls, NOT photosynthetic

animals

Eukaryotes, multicellular, NO cell walls, NOT photosynthetic