Learning Goals: Define microorganism and characterize the main groups of microorganisms. Describe the basic cellular structure of microbes and differentiate between prokaryotic and eukaryotic cell. Explain the importance of studying microbes. Describe the role and impact of microbes on the Earth. Define the main branches of Microbiology Summarize the relative burden of human disease caused by microbes.
What is Microbiology? micron = small and biologia = study of living things Microbiology = study of small living things – How small is “small”? – What do we really mean by living? Working definition: Study of entities too small to be seen with the unaided human eye. (< 0.2 mm = 200 µm = 200,000 nm)
Characteristics of Living Organisms Metabolism – enzyme-catalyzed chemical reactions Bacillus cereus – Yes Bacteriophage T4 – No Reproduction – progeny formed sexually or asexually Bacillus cereus – YesBacteriophage T4 – Yes Differentiation – different cell types can occur Bacillus cereus – YesBacteriophage T4 – No Communication – signaling within and between cells Bacillus cereus – YesBacteriophage T4 – No Locomotion – relative movement of cell or organism Bacillus cereus – YesBacteriophage T4 – No Evolution – genetic change over time Bacillus cereus – YesBacteriophage T4 – Yes
Importance of Microbes The earliest organisms in the fossil record Essential reactions in the environment Can be harnessed to work for us Infectious diseases
Branches of Microbiology Medical Microbiology Public health Microbiology and Epidemiology Immunology
Branches of Microbiology Industrial Microbiology Agricultural Microbiology Environmental Microbiology
Biotechnology Genetic Engineering and Recombinant DNA Technology: genetically modified organisms (GMOs) Bioremediation
Microbial Diseases Pathogens: microbes cause infectious diseases
Microbiology Disciplines by Organism Microbiologists are sometimes referred to by the type of microbial system that they study Bacteriology: Study of prokaryotes Mycology: Study of fungi Phycology: Study of algae Protozoology: The study of protozoa Virology: The study of viruses
Conclusions: Microbiology studies living organisms “too small to be seen by with the naked eye”. They include bacteria, algae, protozoa, fungi, helminths, and viruses. There are two types of cellular structure of microorganisms: prokaryotes and eukaryotes. Viruses are not cellular and can be considered particles. Microorganisms have a crucial effect on the life on Earth.
Conclusions: Humans manipulate microbes to do work for them in industry, medicine, and in caring for the environment. Microbiology is a complex discipline which includes many branches studying different aspects of microbes Infectious diseases are caused by microbes acting as parasites. There are differences in infectious diseases affecting developing and industrialized countries
What Aspects of Microorganisms Will We Study? Cell Structure and Function Cell Growth and Metabolism Microbial Genetics Taxonomy and Evolutionary History Interaction with Living and Non-Living Environment