BIO 220 Microbiology: Relevance and Probiotics

Introduction to Microbiology

• Introduction to Microbiology is a course called BIO 220
• The instructor is Nelson Chu, Ph. D

Microbiology Relevance

• Microbiology is relevant to sex, romaine lettuce, exotic travels, protecting families, bioterrorism, pandemics, dietary supplements, cruise ships, natural disasters, wine, hospitals

Supplements

• A capsule of a probiotic blend has 94 mg and 10 Billion Viable Cells
• The probiotic blend contains Lactobacillus acidophilus, Lactobacillus paracasei, Lactobacillus rhamnosus GG, Bifidobacterium lactis, Bifidobacterium infantis, Lactobacillus salivarius, Bifidobacterium bifidum, Bifidobacterium longum, Lactobacillus reuteri, Lactobacillus casei, Lactobacillus plantarum, and Bifidobacterium breve
• A capsule also has 50mg of Xylooligosaccharides (XOS)
• Other ingredients include: Cellulose, silicon dioxide, magnesium stearate (vegetable source), titanium dioxide

Measles

• Measles cases are surging and it is attributable to the pandemic disrupting childhood vaccinations
• Measles case reports have risen by nearly 80% in the first 2 months of 2022

Biological Weapons

• Military analysts are concerned about North Korea's biological weapons program

Health Issues

• Some California Tough Mudder participants reported rashes and fevers due to bacterial infections
• Some San Diego residents were told to boil tap water due to possible E. coli contamination
• There are cases of Legionnaires' disease linked to two Las Vegas hotels

Humans and the Microbial World

• Microorganisms are too small to be seen with the naked eye
• Microbes include bacteria, fungi (yeasts), protozoa, helminths & viruses
• Microorganisms form the foundation for all life on Earth
• Microorganisms have existed for approximately 3.5 billion years (fossils)
• Plants, animals, modern microorganisms all evolved from ancestral bacteria
• Our life depends on microorganism activities
• Some microorganisms are pathogenic

Microorganism Activities

• Microorganisms decompose organic waste and produce chemical products such as ethanol, acetone, and vitamins
• They also produce fermented foods such as vinegar, cheese, and bread
• Microorganisms produce products used in manufacturing like cellulase as well as disease prevention like vaccines

Decomposition and Nutrient Recycling

• The N, C, S, and P cycles are essential to life

Industrial and Commercial Uses for Microoganisms

• They are used for sewage treatment, bioremediation, and bacterial-derived products

Pathogenesis

• Microorganisms can cause infectious diseases like measles, Strep throat, and meningitis
• They can also cause emerging infectious diseases like SARS-CoV-2 and biofilms like dental plaque

Scientific Names

• The Binomial System of Nomenclature has two words
• The Genus is capitalized
• The Specific species name is not capitalized
• Genus and species are italicized or underlined
• Genus may be abbreviated such as E. coli
• XXXX sp. refers a known genus and species but it is not specifically named
• Members of a species with genetic differences can have a strain designation such as E. coli K12
• Informal names that resemble genus names are not italicized
• Members of the genus Staphylococcus are called staphylococci
• After the first use, the genus name can be abbreviated

Types of Microorganisms

• Bacteria
• Archaea
• Fungi (yeasts only)**
• Protozoa**
• Algae**
• Multicellular Helminths** (some stages are microscopic): parasitic worms
• Viruses
• Note: ** Eukaryotic, in bold...will be studied in BIO 220 (lecture & lab)*

Differentiation of Microorganisms by Structure, Cell Wall, and Nutrition Method

• Bacteria: prokaryotic, has peptidoglycan, Autotrophs & heterotrophs*, See LO Chap 11
• Archaea: prokaryotic, has pseudomurein, Autotrophs & heterotrophs, No known pathogens
• Fungi: eukaryotic, has chitin, heterotrophs, Mold, yeasts, e.g. Candida
• Protozoa: eukaryotic, no wall, same as bacteria, Giardia
• Algae: eukaryotic, has cellulose, autotrophs, Pond scum
• Helminths: eukaryotic, no wall, heterotrophs, Pinworm
• Viruses: N/A, N/A, Measles
• “Autotrophs” use inorganic C (CO₂) and “heterotrophs” uses organic C as carbon source*

Differences Between the 3 Domains of Life

• Cell Type:
  • Bacteria and Archaea are prokaryotic
  • Eukarya are eukaryotic
• Number of Cells:
  • Bacteria and Archaea: unicellular
  • Eukarya: Unicellular or multicellular
• Membrane-bound organelles:
  • Bacteria and Archaea: No
  • Eukarya: Yes
• Ribosomal RNA sequences unique to the group:
  • Bacteria: Yes
  • Archaea: Yes
  • Eukarya: Yes
• Peptidoglycan in cell wall
  • Bacteria: Yes
  • Archaea: No
  • Eukarya: No
• Typical size range
  • Bacteria: 0.3 to 2 micrometers
  • Archaea: 0.3 to 2 micrometers
  • Eukarya: 5 to 50 micrometers

Bacteria

• Bacteria are prokaryotes with a "prenucleus" and no membrame bound orgelles
• Bacteria are single-celled with peptidoglycan cell walls
• Bacteria divides via binary fission and derive nutrition from organic chemicals or by photosynthesis (“carbon source")

Fungi

• Fungi ae eukaryotes with a distinct nucleus and membrane-bound organelles
• Yeasts are unicellular, have a cell wall made from chitin, and are responsible for opportunistic infections (Candida, "yeast" infections) or more serious ones
• Other yeast genera like Saccharomyces make the ethanol in beer & wine or the CO2 for baking.

Protozoa

• Protozoa are eukaryotes that are unicellular and has no cell wall
• Protozoa absorb or ingest organic chemicals and may be motile via pseudopods, cilia, or flagella
• Protozoa are free-living or parasitic and derive nutrients from a living host

Helminths

• Helminths are eukaryotes and multicellular animals with no cell wall
• Helminths are not strictly microorganisms but some have microscopic stages in their life cycle
• Parasitic flatworms such as flukes and tapeworms and roundworms are helminths

Viruses

• Viruses are acellular and consist of DNA or RNA core surrounded by a protein coat
• Viruses may be enclosed in a lipid envelope and can only replicate when they are in a living host cell
• Because they lack a cell wall or a method of nutrition, viruses are not considered alive and are called an "infectious agent"
• Viruses have a nucleic acid genome of DNA or RNA packaged in a protein coat
• Viruses are obligate intracellular agents that multiply using host cell machinery and nutrients
• All forms of life can be infected by different types of viruses and bacteria can be infected by viruses called bacteriophage
• Viruses may kill the host cell or remain within the host cell and replicate viral genetic information as host cell multiplies

History of Microbiology

• Historical knowledge is carried over to current practices
• Living things are composed of little boxes or "cells" and this marked the beginning of cell theory in 1665 by Robert Hooke
• The first microbes were documented by Anton van Leeuwenhoek (he used information from Hooke's work) from 1673-1723

What did Leeuwenhoek do?

• Made simple magnifying glass
• He studied lake water and observed 'animalcules'

Significance of Leeuwenhoek's Discovery

• It provided for life of invisible creatures and it posed the question of where the creatures came from
• It was a spontaneous generation that can life arise from non-living matter
• This became a philosophical/religious/political/cultural issue
• Spontaneous generation was used as an explanation for disease, an example of belief in bad air

Spontaneous Generation Debate

• Spontaneous generation refers to the hypothesis that life arises from nonliving matter with a vital force necessary for life
• The opposing hypothesis is that living cells arise only from preexisting living cells

Louis Pasteur

• In 1861, Pasteur used S-shaped flasks to disprove spontaneous generation
• Pasteur kept microbes out but let air in. The boiled broth in flasks showed no signs of life and the neck of the flask traps microbes
• Microorganisms originate in air or fluids, not mystical forces

Disproving Spontaneous Generation

• Pasteur showed that microbes are everywhere in air, liquids, and solid surfaces. When blocked, microbial contamination is prevented
• Resolving the spontaneous generation controversy, Pasteur took the issue from the realm of philosophical or mystical and shifted it into quantifiable application via the Scientific Method

Pasteur Contributions

• His work laid the foundation for the development of aseptic techniques, which are procedures meant to prevent microbial contamination
• He associating microbes with the spoilage of food and solved this by "pasteurization" where heating the liquid just enough to kill the bacteria without destroying flavor of food
• From this, he believed in germ theory of disease, that microbes can cause disease

Robert Koch Glimpse of History

• Ancients thought diseases were divine punishment
• Leeuwenhoek's discovery of microorganisms in 17th century led people to suspect they might cause disease
• Robert Koch (1876) offered evidence of what is now known as germ theory of disease. Microbes can cause disease
• Koch showed that Bacillus anthracis causes anthrax and later worked on tuberculosis
• He formalized criteria to determine the microbial cause of disease known as Koch's postulates

Koch's Postulates

• Microbe always present with same disease
• Recovered microbe grown as pure culture
• Pure culture causes same disease
• Same microbe as above is recovered

Joseph Lister Glimpse of History

• Joseph Lister revolutionized surgery by introducing methods to reduce wound infection in the 1860s
• He was impressed with Pasteur's work and wondered if tiny minute organisms are responsible infections
• He applied carbolic acid, a disinfectant, onto damaged tissues and decreased infections
• Lister improved methods further by sterilizing instruments and maintaining a clean operating environment, reducing post-surgical infection
• The antiseptical Listerine is named after him after its introduction as a surgical antiseptic in 1879

Edward Jenner Glimpse of History

• Edward Jenner observed milkmaids cannot get smallpox because of their exposure of cowpox, so in 1796 he tested whether prior exposure conferred protection
• He took cowpox blister exudate and added it to the abraded skin of an 8-year-old volunteer, 6 weeks then he later inoculated the boy with smallpox
• The boy did not develop smallpox, so now vaccination can provide protection against an infectious disease and the induction of specific immunity significantly cowpox vaccination is protects against smallpox disease

Chemotherapy Background

Treatment of disease with chemicals is called chemotherapy

• Chemotherapeutic agents treat infectious disease and consist of synthetic drugs or antibiotics
• Antibiotics are chemicals produced by bacteria and fungi that inhibit or kill other microbes

Paul Ehrlich History

• Paul Elrich was a German physician (1854-195) and observed some dyes stain bacterial but stain animal cells
• This indicated fundamental difference between cell types in which he searched for a "magic bullet” that would kill microbial pathogens without harming human host
• In 1910, Ehrlich tested arsenic compounds treat syphilis which caused by spirochete Treponema pallidum
• The 606th tested compound proved effective in that is Arsphenamine known currently as Salvarsan is potentially lethal for patients but did cure infections previously hopeless
• This proved some chemicals can selectively kill microbes

Alexander Fleming Antibiotics Discovery

• Alexander Flemming discovered and identified a compound in 1928 secreted by Penicillum which is toxic to Staphylococcus(penicillin)
• It had shown effective against many bacterial species and unable to purify, he abandoned research
• Chain and Florey purified and tested compounds in 1941 on police officer with Staphylococcus aureus infection but the officer subsequently
• This led to WWII spurred research and development in which penicillin G became the 1st antibiotic and has 1940s: Penicillin tested clinically mass-produced, taking over 10 years from "bench to bedside..."
• Flemming, Chain and Florey awarded Nobel Prize in Physiology or Medicine in 1945 for discovery/development of penicillin

Immunology and Biotechnology

• Immunology is the study of immunity and is used for identification of microorganisms and diagnostic
• The immune system is responsible for defense against infection from cancer
• Biotechnology is the industrial application of microbes/cells/cell components to make useful products

Commercial benefits of microorganisms

• Biotechnology uses microbiological and biochemical techniques to solve practical problems
• Genetic Engineering (use in vitro methods to alter the microbe's genetic information) (BIO 220L experiment)
• Production of medications/vaccines by GEE microorganisms including insulin from treatment of diabetes
• Microbial drug resistance is a major health crisis through overuse/misuse of antibiotics which causes bacterial evolution

Microbiota

• Normal microbiota: microbes which colonize the body for an indefinite period w/o causing disease
• Human microbiome: human body carries enormous population of microorganisms also known the normal microbiota
• Normal microbiota play role against disease by competing against-disease-causing microbes which aids in digestion

Human Microbiome Project

• NIH funds omic studies for normal and altered states
• 1% of microbes can be cultured or DNA sequencing

Emerging Infectious Disease

• Emerging infectious disease is an infectious disease which is new/ changing/increase that has has potential to increase in incidence eg Zika HIV
• They evolve and diseases/disease agents can change and come resistant

Oldest Life

Bacterial have evolved 4.5 bya

• Jan 1, earth forms
• Feb, ocean forms
• Mar. cells appear. Archaea
• Jun O2 appears
• Aug Eukaryotes
• oct multicellular eukaryotes colonies land
• dev 13-26 Age of Dino
• dev 31 -2Homoaopears
• B cells are around for a long time they evolve to fill ecolocial niches and survive with or withour oxygen and acquired mitochondria from bacteria

An introduction to microbiology with Nelson Chu, Ph.D., covering its relevance to a variety of topics. It also covers probiotic supplements, including their ingredients and viable cell counts. An outbreak of measles is also mentioned.