An intro to bacteria, infectious diseases, and antibiotic resistance SUPERBUGS Image: Wikipedia (http://en.wikipedia.org/wiki/File:Average_prokaryote_cell-_en.svg) An intro to bacteria, infectious diseases, and antibiotic resistance

What are bacteria? Single-celled organisms Prokaryotes: genetic material NOT contained in a nucleus Auto-trophs and hetero-trophs Defined as having no nucleus or membrane bound organelles 1-10um in diameterMost have cell walls Contain a single circular chromosome found in the nucleoid region (and plasmids which are small, circular segments of DNA) Small ribosomes Formed about 3.5 billion years ago An autotroph is an organism that produces complex organic compounds (such as carbohydrates, fats, and proteins) from simple inorganic molecules using energy from light (by photosynthesis) or inorganic chemical reactions (chemosynthesis). A heterotroph (Greek heteros = "another” or "different" and trophe = "nutrition") is an organism that uses organic carbon for growth. Left: http://www.faqs.org/photo-dict/phrase/2090/leaf-structure.html Right: http://tangledwing.wordpress.com/2008/06/27/panda-and-bamboo-wallpaper-energy-news-round-up-wombat-news/

How abundant are bacteria? Bacterial Abundance Total bacteria on Earth 5 x 1030 Number of stars in the universe 7 x 1022 Age of the universe in seconds 4.4 x 1017 Bacteria in the human gut 1 x 1014 Global gross product ($/year) 7 x 1013 Cells in the human body 1 x 1013 Texts sent in 2009 1.5 x 1012 People on Earth 6.9 x 109 10X “Abundance” = how many… Notice that there are 10 times more bacterial cells in your gut alone than there are human cells in your entire body! Do you think you are sick because they are there, or that you are healthy because they are there?

All about bacteria… Help make yogurt, cheese, & wine Involved in environmental recycling and clean-up Bacteria live almost anywhere and eat almost anything!! Left: Image of advertisement of live bacterial cultures in yogurt (http://www.grit.com/blogs/Yogurt-Quark-and-More.aspx) Center: Heterotrophic bacteria (http://www.whoi.edu/page.do?pid=20560) Right: Cyanobacteria Oscillatoria (http://ostro.ced.berkeley.edu/~crisr/he/?page_id=78)

How many types of bacteria are there? Bacterial Distribution Insect Species 1-10 million Bacterial species in the soil 4 million Bacterial species in the air Bacterial species in the ocean 2 million Bird Species 10,000 Bacterial species in the human mouth 600 Bacterial Species in the human gut 500 Pathogenic Species 55 Type = species Note that there are really few harmful bacteria compared to all others. MOST BACTERIA ARE HARMLESS OR HELPFUL!

Infectious Diseases Pathogen: a biological agent that causes disease Can be a virus, bacteria, fungi, protozoa, or parasite Infectious diseases are communicable or transmissible from one person to another Pathogens are microorganisms that make you sick/ill.

Protist: Malaria (Plasmodium) Virus: Influenza (H1N1) Protist: Malaria (Plasmodium) Fungi: Plant pathogen (Rigidoporus laetus) H1N1 Virus: http://healthinfoispower.wordpress.com/2009/08/19/nccn-updates-infection-guidelines-to-include-information-about-h1n1-virus-swine-flu/ Marlaria: http://en.wikipedia.org/wiki/File:Malaria.jpg Fungi: http://en.wikipedia.org/wiki/File:Rigidoporus_laetus.jpg

Staph Infection: Staphylococcus aureus Mycobacterium tuberculosis Salmonella typhimurium Tuberculosis: http://feww.wordpress.com/2008/10/08/climate-change-spreads-deadly-dozen-diseases/ Salmonella: http://desled.co.cc/2009/01/salmonella-outbreak-linked-to-peanut-butter/ Staph: http://www.netwellness.org/healthtopics/infectiousdisease/mrsa.cfm

Antibiotics Compounds that kill bacteria or inhibit their growth Naturally produced by microorganisms to kill others Now many are made synthetically Antibiotics are used to treat bacterial infections. Antimicrobials are a broader class of chemical/compounds that kill bacteria, fungi, and protists. Antibiotics can kill a bacteria in several different ways. Some target DNA or protein synthesis, others interrupt the cell membrane. Prontosil, the first commercially available antibacterial antibiotic was developed by a research team led by Gerhard Domagk (who received the 1939 Nobel Prize for Medicine for his efforts) at the Bayer Laboratories of the IG Farben conglomerate in Germany. The development of penicillin led to renewed interest in the search for antibiotic compounds with similar capabilities.[17] Because of their discovery of penicillin Ernst Chain, Howard Florey and Alexander Fleming shared the 1945 Nobel Prize in Medicine.

Antibiotics Susceptible vs. Resistant Lawn Antibiotic Clearing Susceptible: likely to be influenced by Resistant: drug does not work on the bacteria (no longer kills it) Image: http://en.wikipedia.org/wiki/File:Staphylococcus_aureus_(AB_Test).jpg Clearing

Why is resistance bad? Because you can’t treat the disease! The patient will remain sick 

How do you get resistance? Usually from mutation in DNA Genetic mutations can be passed to offspring… Leads to evolution! Evolution is the change in the inherited traits of a population of organisms through successive generations. (Changes in a population over time).

Genetic Mutation NATURAL SELECTION!

Susceptible + Antibiotic Antibiotic Resistant

What can you do to help? Follow the directions! Take antibiotics only when necessary