Introduction to Microbes

• There are big ideas in biotech like models, interaction, systems, and diversity
• Key questions include "What is microbial biotechnology?", "How can we identify bacteria based on their characteristics?" and "How can we apply knowledge of bacterial characteristics in this field?"
• A question to consider is "Are microbes friends or foes?"
• The learning outcomes are to list positive and negative roles of microbes, understand the bacterial naming system, describe bacterial isolation using the 16-streak method and explain aseptic techniques and their importance
• Without microorganisms, no life can exist on Earth

Introducing Microbes

• Bacteria are more than just pathogens, they can be helpful or harmful
• Viruses are the smallest microbes, but debatable if they are actually alive
• Fungi are more than just mushrooms
• Protozoa have a taste for waste
• Algae are microbial powerhouses essential for life
• Archaea were first found existing on the edge of life

Microbes and Disease

• Microbial diseases range from minor irritants to death
• Microbes cause disease by destroying living cells/tissues, or by releasing chemicals that interfere with normal cell activities
• Antibiotic resistance is an issue
• Bacteria that resist last-resort drugs were identified as an issue in China
• The gene that makes bacteria resistant to the antibiotic colistin has been found in at least 19 countries
• Antibiotic-resistant bacteria sicken 2 million Americans each year and kill 23,000

Infectious Agents

• Bioterrorism refers to biological agents (microbes or toxins) used as weapons for political agendas
• Category A Agents are easily disseminated, have high mortality rates, cause public panic, and require special action for public health preparedness
• Category B Agents are moderately easy to disseminate, have moderate morbidity and low mortality, and require specific enhancements of the CDC's diagnostic capacity
• Category C Agents are emerging pathogens with availability, ease of production and dissemination, and high morbidity and mortality

Therapeutic Products

• Microbes are used to create health products, vaccines, and drugs
• Penicillium chrysogenum is used in therapeutic agents
• Scientists learned that certain molds killed some bacteria
• Scientists grew Penicillium mold in fermentation tanks via sugar
• Scientists separated penicillin from the mold
• Penicillin is purified before use as an antibiotic medicine

Microbes in the Food Industry

• Microbes can lead to food spoilage
• Microbes are used in food manufacturing
• The three microorganisms used in soy sauce brewing are koji mold, lactic acid bacteria, and yeast
• Acetic acid bacteria, yeast, and lactic acid bacteria give coffee its flavor

Industrial Microbiology

• Microbes are used to produce enzymes
• Microbes help with sewage treatment
• Primary sewage treatment is a physical process that uses screens and a grit tank
• Secondary sewage treatment is a biological process where aerobic bacteria remove 90% of dissolved and biodegradable organic wastes
• Microbes decay and recycle
• Microbes can be used in bio-remediation
• Alcanivorax borkumensis is a tiny bacteria that's able to clean up oil spills

Summary of Roles of Microbes

• Negative roles are infectious agents and food spoilage
• Positive roles are therapeutic agents, manufacturing industrial and food products, and bioremediation

Prokaryotes

• Prokaryotes have different shapes
• Bacillus is rod-shaped, coccus is spherical, and spirillum is corkscrew-shaped

Bacterial Nomenclature

• Group/Family is the broadest classification, while strain is the most specific subset

The Binomial Naming System

• Species names are usually derivatives of descriptive properties
• An example is Staphylococcus aureus
• Escherichia coli, Streptococcus pneumoniae, and Lactobacillus casei Shirota strain are all examples of binomial names
• Escherichia coli or E. coli is a common name for the bacteria
• Typewritten names should be italicized, while handwritten names should be underlined

Isolating Bacteria

• Most microbes from natural sources consist of a heterogeneous mixture
• Isolating requires that each species of bacteria must be maintained as a pure culture
• Pure colony: colony w/ only one STRAIN of microorganism
• All colonies originate from one single bacterial cell
• CFU is the number of bacteria that can form a colony
• A quantity of 1 colony is equal to 1 single bacterium at the time of plating
• The 16-streak method is used isolate bacteria by dilution
• It is important to flame the loop to sterilize it before streaking
• A unit to indicate the number of bacteria capable of multiplying is called a colony forming unit

Aseptic Techniques

• Microbes are everywhere, so it is important to perform a series of practices and procedures under clinical and lab settings to prevent the contamination of unwanted microorganisms
• Aseptic techniques are used to prevent wound infection in patients and lab cultures from contamination
• General aseptic techniques: complete all operations quickly, use sterile materials only, disinfect work area before starting
• Pipette tips must not come into contact with non-sterile surfaces
• Vessels must be open for the minimum amount of time possible
• Openings on test tubes/bottles must be warmed by flame
• A heating process produces a convection current away, helping prevent bacteria from nearing the bottle
• Operations must be near a flame where air currents are drawn upwards
• Close doors/windows & avoid sudden movements
• Avoid talking and breathing heavily
• Sterilize items after contact with microorganisms
• When pouring a plate, sterilized molten agar is poured in and left to set
• Solidified agar should be brought to a laminar flow hood to air dry

Explore the diverse world of microbes, including bacteria, viruses, fungi, protozoa, algae, and archaea. Understand their roles, both beneficial and harmful, and how they impact life on Earth. Learn about bacterial identification, naming systems, and aseptic techniques.