Introduction to Bacteriology

What are some examples of microbes? Chapter 1 The Microbial World and You What is Microbiology? Microbes, or microorganisms are minute living things that are usually unable to be viewed with the naked eye. What are some examples of microbes? Bacteria, fungi, protozoa, algae, viruses are examples! Some are pathogenic “Germ” refers to a rapidly growing cell.

Decompose organic waste Chapter 1 The Microbial World and You What is Microbiology? Microbes: Decompose organic waste Are producers in the ecosystem by photosynthesis Produce industrial chemicals such as ethyl alcohol and acetone Produce fermented foods such as vinegar, cheese, and bread

Chapter 1 The Microbial World and You What is Microbiology?

Knowledge of Microbes allows humans to Prevent food spoilage Chapter 1 The Microbial World and You What is Microbiology? Knowledge of Microbes allows humans to Prevent food spoilage Prevent disease occurrence Led to aseptic techniques to prevent contamination in medicine and in microbiology laboratories.

Ancestors of bacteria were the first life on Earth. Chapter 1 The Microbial World and You History of Microbiology Ancestors of bacteria were the first life on Earth.

The first microbes were observed in 1673. Chapter 1 The Microbial World and You History of Microbiology The first microbes were observed in 1673. In 1665, Robert Hooke (Englishman) reported that living things were composed of little boxes or cells.

Chapter 1 The Microbial World and You History of Microbiology 1673-1723, Antoni van Leeuwenhoek (Dutch) described live microorganisms that he observed in teeth scrapings, rain water, and peppercorn infusions.

Many believed spontaneous generation: Chapter 1 The Microbial World and You History of Microbiology Many believed spontaneous generation: life can arise from non-living matter In 1668, the Italian physician Francesco Redi performed an experiment to disprove spontaneous generation. Can you think of an experiment that could disprove spontaneous generation?

Redi filled six jars with decaying meat. Conditions Results Chapter 1 The Microbial World and You History of Microbiology Redi filled six jars with decaying meat. Conditions Results 3 jars covered with fine net No maggots 3 open jars Maggots appeared From where did the maggots come? What was the purpose of the sealed jars? Spontaneous generation or biogenesis?

So now there are two hypotheses: Chapter 1 The Microbial World and You History of Microbiology So now there are two hypotheses: The hypothesis that living organisms arise from nonliving matter is called spontaneous generation. According to spontaneous generation, a “vital force’ Forms life. The Alternative hypothesis, that the living organisms arise from preexisting life, is called biogenesis.

Nutrient broth placed in flask, heated, not sealed Microbial growth Chapter 1 The Microbial World and You History of Microbiology 1861: Louis Pasteur demonstrated that microorganisms are present in the air. Conditions Results Nutrient broth placed in flask, heated, not sealed Microbial growth Nutrient broth placed in flask, heated, then sealed No microbial growth Spontaneous generation or biogenesis?

Chapter 1 The Microbial World and You History of Microbiology Next experiment, Pasteur’s S-shaped flask kept microbes out but let air in. These experiments form the basis of aseptic technique

The Golden Age of Microbiology 1857-1914 Chapter 1 The Microbial World and You History of Microbiology The Golden Age of Microbiology 1857-1914 Beginning with Pasteur’s work, discoveries included the relationship between microbes and disease, immunity, and antimicrobial drugs

Pasteur showed that microbes are responsible for fermentation. Chapter 1 The Microbial World and You History of Microbiology Pasteur showed that microbes are responsible for fermentation. Fermentation is the conversation of sugar to alcohol to make beer and wine. Microbial growth is also responsible for spoilage of food. Bacteria that use alcohol and produce acetic acid spoil wine by turning it to vinegar (acetic acid).

Chapter 1 The Microbial World and You History of Microbiology Pasteur demonstrated that these spoilage bacteria could be killed by heat that was not hot enough to evaporate the alcohol in wine. This application of a high heat for a short time is called pasteurization.

The Germ Theory of Disease Chapter 1 The Microbial World and You History of Microbiology The Germ Theory of Disease 1860s: Joseph Lister used a chemical disinfectant to prevent surgical wound infections after looking at Pasteur’s work showing microbes are in the air, can spoil food, and cause animal diseases.

Chapter 1 The Microbial World and You History of Microbiology Koch's Postulates are used to prove the cause of an infectious disease.

Chapter 1 The Microbial World and You History of Microbiology Koch's Postulates are a sequence of experimental steps to relate a specific microbe to a specific disease.

Chemotherapy – treatment with chemicals Chapter 1 The Microbial World and You History of Microbiology Chemotherapy – treatment with chemicals Chemotherapeutic agents used to treat infectious disease can be synthetic drugs or antibiotics. Antibiotics are chemicals produced by bacteria and fungi that inhibit or kill other microbes. Quinine from tree bark was long used to treat malaria.

Chemotherapy – treatment with chemicals Chapter 1 The Microbial World and You History of Microbiology Chemotherapy – treatment with chemicals 1910: Paul Ehrlich developed a synthetic arsenic drug, salvarsan, to treat syphilis. 1930s: Sulfonamides were synthesized.

1928: Alexander Fleming discovered the first antibiotic. Chapter 1 The Microbial World and You History of Microbiology 1928: Alexander Fleming discovered the first antibiotic. He observed that Penicillium fungus made an antibiotic, penicillin, that killed S. aureus. 1940s: Penicillin was tested clinically and mass produced.

Bacteriology is the study of bacteria. Mycology is the study of fungi. Chapter 1 The Microbial World and You Modern Developments Bacteriology is the study of bacteria. Mycology is the study of fungi. Parasitology is the study of protozoa and parasitic worms. Recent advances in genomics, the study of an organism’s genes, have provided new tools for classifying microorganisms.

The science of classifying organisms Chapter 1 The Microbial World and You Classification of Microbes Taxonomy The science of classifying organisms Provides universal names for organisms Provides a reference for identifying organisms

Systematics or phylogeny Chapter 1 The Microbial World and You Classification of Microbes Taxonomy Systematics or phylogeny The study of the evolutionary history of organisms All Species Inventory (2001-2025) To identify all species of life on Earth

Dumb Kings Play Chess On Funny Green Squares Taxonomic Hierarchy Chapter 1 The Microbial World and You Classification of Microbes Taxonomic Hierarchy Domain Kingdom Phylum Class Order Family Genus Species Dumb Kings Play Chess On Funny Green Squares

Taxonomic Hierarchy Domain Chapter 1 The Microbial World and You Classification of Microbes Taxonomic Hierarchy Domain Kingdom Phylum Class Order Family Genus Species Binomal Nomenclature uses the Genus and Species name to identify each creature.

There is a specific way to write each name. Chapter 1 The Microbial World and You Classification of Microbes Taxonomic Hierarchy Each name is Latinized There is a specific way to write each name. Homo sapiens The first word is capitalized Name is in italics Homo sapiens H. sapiens

Chapter 1 The Microbial World and You

Chapter 1 The Microbial World and You

Chapter 1 The Microbial World and You

Bacteria (or Eubacteria) Chapter 1 The Microbial World and You Bacteria (or Eubacteria) Most abundant on earth They are nitrogen fixers and recycle carbon No membrane bound organelles

Archaea Methanogens Halophiles Hyperthermophiles Chapter 1 The Microbial World and You Archaea Methanogens Halophiles Hyperthermophiles

Classification of Microbes Chapter 1 The Microbial World and You Classification of Microbes

This term has been replaced by microbiota. Chapter 1 The Microbial World and You Microbes and Human Disease Bacteria were once classified as plants which gave rise to use of the term flora for microbes. This term has been replaced by microbiota. Microbes normally present in and on the human body are called normal microbiota.

Normal microbiota prevent growth of pathogens. Chapter 1 The Microbial World and You Microbes and Human Disease Normal microbiota prevent growth of pathogens. Normal microbiota produce growth factors such as folic acid and vitamin K. Resistance is the ability of the body to ward off disease. Resistance factors include skin, stomach acid, and antimicrobial chemicals.

When a pathogen overcomes the host’s resistance, disease results. Chapter 1 The Microbial World and You Microbes and Human Disease When a pathogen overcomes the host’s resistance, disease results. Emerging Infectious Diseases (EID): New diseases and diseases increasing in incidence

species –a collection of bacterial cells which share an overall similar pattern of traits in contrast to other bacteria whose pattern differs significantly strain or variety – a culture derived from a single parent that differs in structure or metabolism from other cultures of that species (biovars, morphovars) type – a subspecies that can show differences in antigenic makeup (serotype or serovar), susceptibility to bacterial viruses (phage type) and in pathogenicity (pathotype).