History of Microbiology

Question 1

Evolutionary Timeline

Answer 1

Approximately 3.5 billion years ago prokaryotes appeared. With the increase of O2 on earth thanks to cyanobacteria, eukaryotes appeared about 1.75 billion years ago.

Question 2

Fermentation

Answer 2

Metabolic process that uses organic molecules as the final electron acceptor; Ex: Lactic Acid Fermentation

Question 3

Pasteurization

Answer 3

Partial sterilization of a substance and especially a liquid (like milk) at a temperature and for a period of exposure that destroys objectionable organisms without a major chemical alteration of the substance

Question 4

Parts of Early Microbiology

Answer 4

Greeks and Romans
Miasma Theory
Hippocrates
Thucydides
Varro

Question 5

Ancient Rome and Microbiology Advancement

Answer 5

Made aqueducts which brought fresh water into the city. There was also a giant sewer that carried away waste, thought to have helped them avoid many polluted water caused diseases.

Question 6

Miasma Theory

Answer 6

Ancient Greek civilization attributed disease to bad air and called them, “miasmatic odors”. Hygiene products were built of this idea.

Question 7

Hippocrates (460-370 BC)

Answer 7

“Father of Western Medicine”; proposed that diseases had natural causes rather than supernatural causes

Question 8

Thucydides (460-395 BC)

Answer 8

“Father of Scientific History”- advocated for evidence based analysis of cause and effect reasoning.
He made observations of the Athenian plague and noticed that survivors did not get reinfected, demonstrated an early understanding of immunity.

Question 9

Varro (116-27 BC)

Answer 9

Prolific Roman Writer, first to propose that things we can’t see (microorganisms) cause diseases.
called them “minute creatures”

Question 10

The Microscope

Answer 10

Galileo
Janssen
van Leewenhoek
Robert Hooke

Question 11

Galileo (1564-1642)

Answer 11

Pioneer of Microscopy. Developed the telescope

Question 12

Janssen (late 1500s-early 1600s)

Answer 12

Invented the first compound microscope. Spectacle makers in Holland

Question 13

van Leeuwenhoek (1632-1723)

Answer 13

“Father of Microbiology/Bacteriology”, first to develop lens powerful enough to view microbes. He discovered protists and bacteria. He called them “animalcules” meaning little animals.

Question 14

Robert Hooke (1635-1703)

Answer 14

First to describe and coin the term cells when he observed thin slices of cork under a microscope (of his own making) and saw tiny box like structures. Called them cells after the cells in a monastery! Led to development of cell theory

Question 15

Spontaneous Generation Theory

Answer 15

Notion that life can arise from living matter

Question 16

Scientists and the Spontaneous Generation Theory

Answer 16

Aristotle (pro)
Van Helmont (pro)
Redi (anti)
Needham (pro)
Spallanzani (anti)
Pasteur (anti)

Question 17

Aristotle (384-322 BC)

Answer 17

earliest recorded scholar to propose spontaneous generation

Question 18

Van Helmont (mid-1500s)

Answer 18

pro- spontaneous generation theory. proposed that mice could arise from rags and wheat kernels

Question 19

Redi (1668)

Answer 19

first to refute SGT. Experiment involving jars of meat covered by (1) nothing- maggots got on meat (2) Cork sealed- no maggots (3) Gauze covered. - maggots on gauze only not on meat

Question 20

Needham (1745)

Answer 20

Supporter of SGT. Boiled broth to kill microbes, but the microbes were present days later. Probably didn’t boil the water hot enough or long enough.

Question 21

Spallanzani (1740-1750s)

Answer 21

Refuted Needham’s SG conclusions, redid his experiment

Question 22

Pasteur (1859) and swan neck flask experiment to disprove SGT

Answer 22

first to officially disprove SGT. He designed swan necked flasks that would allow air through (or pneuma/vital force) but the flasks would trap microbes and prevent them from getting to the broth. The broth was boiled to purify it. Then they were incubated for a few days. Air/vital force had access to the broth but microbes did not because they would get stuck in the flask. There was no microbes after incubation period. Repetition but without swan neck portion of flask, microbes in the air had access to the broth and there was significant microbe growth after incubation period. CONCLUSION: disproved SGT and gave evidence that microorganisms exist. Laid the foundation for Germ theory of disease.

Question 23

Cell Theory

Answer 23

1.) All cells only come from other cells (biogenesis)
2.) Cells are the fundamental units of organisms.
3.) All living things are made of at least one cell

Question 24

Scientists contributing to cell theory

Answer 24

Robert Hooke
van Leeuwenhoek

Question 25

Robert Hooke and Cell Theory

Answer 25

Coined the term cell. Built his own compounds microscope and wrote his observations in a book called "Micrographia". Discovered plant cells when he looked at cork but had no idea that they were alive

Question 26

van Leeuwenhoek and Cell Theory

Answer 26

Used his microscopes to view living cells and view small microorganisms he called "animalcules". First description of bacteria that he viewed by scraping plague off his own teeth.

Question 27

Endosymbiotic Theory

Answer 27

theory that mitochondria and chloroplasts arose as a result of a prokaryotic host establishing a symbiotic relationship with a eukaryotic host, and were engulfed by a larger cell after once being free-living cells Bases for theory: 1.) DNA and ribosomes of mitochondria and chloroplasts are similar to bacteria counterparts 2.) Binary fission of these organelles resemble binary fission of bacteria. Does not participate in mitosis like eukaryotes.

Question 28

Scientists who were proponents of endosymbiotic theory

Answer 28

Mereschkowski Wallin Marguilis

Question 29

Mereschkowski (1905)

Answer 29

Father of EST: 1st articulation of EST: suggested that chloroplasts may have originated from ancestral photosynthetic bacteria living symbiotically in a eukaryotic cell based on chloroplasts' ability to reproduce independently

Question 30

Wallin (1920s)

Answer 30

EST: Put EST to test using objective investigation- experimentally examined similarities between mitochondria, chloroplasts, and bacteria.

Question 31

Margulis (1967)

Answer 31

Popularized EST: Argued that organelles like mitochondria and chloroplasts are of prokaryotic origin. Provided evidence and published it.

Question 32

Germ Theory of Disease

Answer 32

states that diseases may result from microbial infection.

Question 33

Evolution

Answer 33

concept that living organisms gradually change over time- these changes are expressed as functional and structural adaptations that lead to variation within a species or creation of a new species.

Question 34

Proponents of GTD

Answer 34

Fracastro Semmelweis Snow Pasteur Lister Koch

Question 35

Fracastro (1540s)

Answer 35

Early proponent of GTD. Proposed that "spores" , invisible particles were transferred between individuals through direct contact and are the cause of the transmission of contagious diseases. Ideas were not popular.

Question 36

Semmelweis (1850s)

Answer 36

GTD: Proposed handwashing to prevent transfer of disease between patients by physicians. Hungarian obstetrician who observed that women who gave birth in hospitals staffed by medical students and physicians were much more likely to get puerperal fever (10-20% mortality) after childbirth compared to hospitals staffed with midwives (1% mortality). He noticed that medical students and physicians were not washing their hands after autopsies before giving vaginal examinations.

Question 37

Snow (1850s)

Answer 37

Father of epidemiology. Conducted studies to track cholera outbreaks in London and traced them back to a polluted water source. First known epidemiological study and first known public health response to epidemic.

Question 38

Pasteur (1850s) and GTD

Answer 38

-Discovered that fermentation was caused by microorganisms and said that if they could cause food spoilage they could also cause infection- laid the foundation of GTD also with his swan-necked bottle experiments which showed that microbes existed in the air -showed that individual microbial strains had unique properties -Invented pasteurization -Developed vaccines including for rabies in humans and animals

Question 39

Lister (1867)

Answer 39

Developed procedures for proper care of surgical wounds and sterilization of surgical equipment to reduce postsurgical infection.

Question 40

Koch

Answer 40

German physician, first to demonstrate the connection between a single, isolated microbe and a known human disease -Discovered the bacteria that causes anthrax, cholera, and tuberculosis. -Came up with Koch's Postulates that summarize his method for determining whether microbe was the cause of a particular disease

Question 41

Koch's Postulates

Answer 41

1.) The suspected pathogenic organism must be present in all cases of the diseases and absent from healthy animals 2.) The suspected organism should be grown in pure culture 3.) The isolated organism must cause the same disease when inoculated into a healthy host 4.) The organism must be reisolated from the inoculated host and shown to the the same as the original

Question 42

Taxonomy

Answer 42

the study of scientific classification

Question 43

Phylogeny

Answer 43

the ordering of species into higher taxa and the construction of evolutionary trees based on evolutionary relationships (evolutionary distance)

Question 44

Taxonomic Classifications

Answer 44

Dear King Philip Came Over For Great Spaghetti Sauce :) Domain Kingdom (just eukarya) Phylum Class Order Family Genus Species Strain

Question 45

Scientists and Classification

Answer 45

Linnaeus Cohn Haeckel Whittaker Woese and Fox

Question 46

Linnaeus (1735)

Answer 46

"Father of Modern Taxonomy" Swedish botanist, zoologist, and physician. Early taxonomist, developed new system for categorizing plants and animals -> Linnean Taxonomy, formalized binomial nomenclature

Question 47

Binomial Nomenclature

Answer 47

a universal convention for the scientific naming of organisms which includes the Latin genus and species (and in some causes subspecies/strain) Ex: Homo sapiens (underline when written). After first mention, abbreviated form is first initial of genus and full species name.

Question 48

Cohn (1860s)

Answer 48

First to publish taxonomic record of bacteria, German botanist and classified bacteria as plants based on shape and arrangement. Also discovered endospores in certain bacteria and notes their resistance to high temperatures.

Question 49

Haeckel (1866)

Answer 49

Proposed the addition of a third kingdom (Protista) to the two-kingdom system created by Linnaeus. Three kingdom classification system was then Animalia, Plantae, and Protista. Later proposed a fourth kingdom system that included Monera for unicellular organisms lacking a nucleus (like bacteria).

Question 50

Whittaker (1969)

Answer 50

Proposed the addition of another kingdom: Fungi so it became a five kingdom system. So the kingdom system now consisted of [Animalia, Plantae, Fungi, Monera, Protista] Also added super kingdom level (domain) to distinguish between organisms that have a membrane-bound nucleus (eukaryotes) and those that do not (prokaryotes)

Question 51

Woese and Fox (1970s)

Answer 51

Discovered "living record" of evolution of organisms and created a genetics based tree of life based on similarities and differences in gene sequences coding for rRNA. They discovered Archaebacteria and created the three current domains of Bacteria, Archaea, and Eukarya, where Archaea is closer to Eukarya.

Question 52

Horizontal Gene Transfer

Answer 52

the unidirectional transfer of genetic information between unrelated organisms; compare to vertical gene transfer -major factor in evolution of many organisms -allows bacteria to acquire new traits, such as antibiotic resistance and metabolic capabilities.

Question 53

Vertical Gene Transfer

Answer 53

gene transfer from a parent to a sex cell; compare to horizontal gene transfer *passage of genetic information from parents to offspring.* -sexual or asexual reproduction -can happen in both prokaryotic and eukaryotic species. -ensures that the identity of a species is maintained. -can lead to gradual changes in the frequency of a trait in a population over time. -can spread antibiotic resistance genes in bacteria.

Question 54

Vertical vs. Horizontal Gene Transfer

Answer 54

-Vertical gene transfer is the transfer of genetic material from a parent to offspring during reproduction. Horizontal gene transfer is the transfer of genetic material between organisms that are not direct decedents of one another. -Vertical gene transfer maintains genetic stability of a species while horizontal gene transfer can introduce signific genetic diversity and drive rapid evolutionary change especially in bacteria.

Question 55

Species

Answer 55

Fundamental evolutionary classification groups

Question 56

Eukaryotic Species

Answer 56

different species cannot interbreed to produce viable offspring

Question 57

Prokaryotic Species

Answer 57

a collection of strains that all share the same major properties and differ in one or more significant properties from other collections of strains; defined phylogenetically as a monophyletic (descended from one ancestor), exclusive group based on DNA sequence; To classify bacteria as the same species, scientists look at their DNA and genetic similarities: Genomic hybridization (≥70%) → If at least 70% of their DNA sequences match, they are considered the same species. 16S rRNA gene similarity (≤3% difference) → If their 16S rRNA gene sequences are at least 97% similar, they likely belong to the same species.

Question 58

Scientific Naming Rules

Answer 58

Binomial, developed by Linnaeus - Must be italicized or underlined - genus is capitalized and will be abbreviated after first use -the term species can be used in place of an actual species if multiple species or unknown species are being discussed. -A species can have different strains (e.g., E. coli O157:H7 vs. E. coli K-12). -Strains are written after the species name (not italicized).

Question 59

Bergey's Manuals

Answer 59

standard references for identifying and classifying bacteria and other prokaryotic organisms

Question 60

Subspecies/strains

Answer 60

-different strains may be nearly identical genetically, but they can have very different attributes -Ex: E.coli 0157 is the one that makes you sick but most do not cause disease. Some are part of your normal flora.

Question 61

Vaccination (immunization)

Answer 61

inoculation of a host with inactive, weakened, attenuated, or a similar species/strain, or pathogen-products to stimulate protective immunity.

Question 62

Jenner (1798)

Answer 62

Father of Western Immunizations and Vaccinations. English doctor who took cow pox scrapings and exposed people to prevent small pox, first small pox vaccine

Question 63

Scientists involved in Staining and Culturing Techniques

Answer 63

Gram Petri

Question 64

Gram (1884)

Answer 64

Danish doctor and botanist who developed Gram Stain for bacteria while examining tissues from patients with pneumonia, which is crucial stain for bacterial classification

Question 65

Petri (1887)

Answer 65

Doctor who worked as an assistant under Koch, invented the petri dish which is the dish that holds the nutrients to allow microorganisms to grow in a lab.

Question 66

Antimicrobial Therapy

Answer 66

the use of medications to treat infections caused by microorganisms, such as bacteria, fungi, viruses, and parasites

Question 67

Scientists discovering antimicrobial therapies

Answer 67

Ehrlich Fleming Florey and Chain Elizabeth Bugie Gregory

Question 68

Ehrlich (1890)

Answer 68

Won nobel prize in 1908 with Metchnikoff for his contribution to immunity, also contributed to antimicrobial chemotherapies

Question 69

Fleming (1928)

Answer 69

Won Nobel prize in 1945 for his work on penicillin, he discovered penicillin

Question 70

Florey and Chain (1928)

Answer 70

synthesized penicillin so it wasn't as toxic for humans

Question 71

Scientists and Immunity

Answer 71

Metchnikoff (and Ehrlich who worked with him) Thucydides: father of scientific history, made observations of the Athenian plague and notes that survivors did not get reinfected pointing towards an early understanding of immunity

Question 72

Metchnikoff (1884)

Answer 72

Father of Natural Immunity. Discovered phagocytes and their role in immunity (white blood cells that engulf and destroy foreign particles like bacteria, viruses and dead cells). -Won Nobel prize in 1908 with Ehrlich

Question 73

Scientists involved in Genetics and Molecular Biology

Answer 73

Griffith Edelman and Porter Epstein, Achlong, and Barr Berg, Boyer, and Cohen

Question 74

Griffith (1928)

Answer 74

Discovered horizontal gene transfer called transformation- (a genetic process in bacteria where a recipient bacterium acquires and incorporates exogenous DNA into its own genome.)

Question 75

Edelman and Porter (1960s)

Answer 75

Discovered the structure of antibodies (part of immune system, produced by body). Won Nobel prize in 1972

Question 76

Epstein, Achlong, and Barr (1964)

Answer 76

Discovered Herpes virus now called Epstein-Barr virus (responsible for mononucleosis) that can cause cancer.

Question 77

Berg, Boyer, and Cohen (1970s)

Answer 77

Pioneered recombinant DNA technology, laying the groundwork for genetic engineering. Boyer grew up in Derry and graduated from Saint Vincent College in 1958 with degrees in biology and chemistry.

Question 78

Fanny Hess (1880s)

Answer 78

proposed the use of agar as a growth medium for microbes

Question 79

Ann Louise Bishop (1930s)

Answer 79

she studied the drug resistance in the protozoan that cause malaria (Plasmodium)

Question 80

Elizabeth Bugie Gregory (1940s)

Answer 80

best known for work in discovery and development of streptomycin, the first effective treatment for tuberculosis. advanced understanding of antimicrobial therapy

Question 81

June Almedia (1960s)

Answer 81

Scottish virologist who developed new methods for viral imaging and diagnosis. Used electron microscopy to identify many previously unidentified viruses. She was the first to identify the rubella virus and discovered that Hepatitis B has two parts.

Question 82

Dorothy Crowfoot Hodkin (1940s)

Answer 82

Discovered the structure of penicillin, insulin, and vitamin B12 using x-ray crystallography. Nobel prize in chemistry in 1964

Question 83

Esther Lederberg (1940s)

Answer 83

Discovered bacteria conjugation and contributed to the understanding of microbial genetics, which is fundamental for vaccine development. Also discovered lambda bacteriophage, a bacterial virus that infects E.coli

Question 84

Ruth Ella Moore (1930s)

Answer 84

first African American woman to be awarded a PhD in a natural science. Researched tuberculosis, immunology, dental caries, microorganism response to antibiotics, and differences in blood types.

Question 85

Hildrus Augustus Poindexter (1930s)

Answer 85

studied epidemiology of tropical disease and bacteriology. discovered Azotobacter, a nitrogen fixing species of bacteria helping to demonstrate how soil and water microorganisms play a crucial role in the nitrogen cycle. One of the few African American microbiologists during his time. First African American to receive both a PhD and MD.

Question 86

Emmy Klieneberger-Nobel (1930s)

Answer 86

first female lecturer on bacteriology. first to differentiate between mycoplasms and other types of bacteria. developed nutrient agar blend that allowed bronchopneumonia to be grown in labs and discovered pathogenic species of mycoplasms.

Question 87

Isabella Price (1950s)

Answer 87

developed vaccines to prevent diseases from killing birds, conducted research that resulted in better control of avian cholera.

Question 88

Marjory Stephenson (1930s)

Answer 88

contributions in bacterial metabolism. studied lactase of the intestinal mucosa and found that the enzyme was inhibited by glucose and not galactose. She then worked on ester synthesis and metabolism in in experimental diabetes.

Question 89

Elizabeth Gregory Bugie

Answer 89

discovery of streptomycin, the first effective treatment for tuberculosis. Improved understanding of antimicrobial therapy and has had a lasting impact on the treatment of infectious diseases, particularly tuberculosis.