Crafty Microbiology: Teaching Microbiology Skills Online

Crafty Microbiology: Teaching Microbiology Skills Online

Crisis inspires innovation! We developed Crafty Microbiology to teach essential microbiology skills at home using safe, common, cheap craft supplies and disposable lab tools. A.M. Estes, A.S. Jozwick, and J.E. Kerr 2021 How can you teach students fundamental microbiology skills at home – safely? The COVID-19 pandemic has been quite the disruptor for educators and students alike. To stop the spread of this virus, we human hosts need to stay away from each other! SARS-CoV2 is super tricky since many infected people don’t show symptoms or have mild symptoms. So what do you do when the skills your students need to learn can’t be done face-to-face? In-person Microbiology Labs Microbiology laboratory, in particular, is tough to teach to students at home. Typically students learn how to grow and test non-disease-causing bacteria in the Microbiology teaching labs on campus. Growing bacteria requires special media “food” for the bacteria, incubators to keep the cultures at the right temperature, and lab equipment – including Bunsen burners and special tools for moving the bacteria. A fundamental skill is learning “Sterile” or “Aseptic” technique. Students learn how to grow only the non-pathogenic, Risk Group 1 microbes they are given. Sounds easy – right? Well, no.

The Great Yogurt Experiment: Part II – Mesophilic (room temperature) Heirloom yogurt

The Great Yogurt Experiment: Part II – Mesophilic (room temperature) Heirloom yogurt

Tasting the bacterial diversity and seeing pH difference using yogurt fermentation for microbiology teaching. I love the idea that invisible microbes can change their habitat so much we macro-organisms will pay attention and even help them! After all, people have maintained yogurt cultures for generations. Take for example the Heirloom yogurts from Culture for Health that I have been playing with and am considering sending to my General Microbiology class this semester. One overarching theme in my microbiology class is always that microbial diversity provides multiple solutions to the same “problem”. Diversity Matters! In this case – different combinations of bacteria can take the same milk, break-up the milk sugars, and poop out lactic acid. The lactic acid lowers the pH of the yogurt, which protects yogurt from pathogenic bacteria (molds can still grow though given enough time). Lactic acid gives the tart, sour taste to yogurt. To teach my General Microbiology students that microbes – just by growing – can dramatically change their habitat. This semester students will culture their own yogurt to see and taste the difference! The problem is most store-bought yogurts grow best at 113 °F (45 °C). That’s pretty warm. That was tricky during my

Microbial Trash is Human Treasure, Part II: MudWatt Captures Bacterial Poop!

Microbial Trash is Human Treasure, Part II: MudWatt Captures Bacterial Poop!

MudWatt – the Microbial Fuel Cell STEM kid – generates electricity from bacterial poop! Yes, really! The soil under your feet hosts a clean, sustainable source of energy. Geobacter sp. and Shewanella sp., soil bacteria, “poop” electricity. You select the soil, set up the unit, download the app, and wait for the LED to begin blinking. As the number of bacteria increase, the LED blinks faster. The app records and graphs your MudWatt energy, predicts and graphs bacterial populations, and unlocks cool facts and a graphic novel to teach what’s going on. Capture the Waste! When any organisms breaks down food, it releases the energy stored in that food in the form of electrons. With most organisms, from mammals to microbes, the electron “waste” binds to oxygen, iron, or sulfur inside the cell(s) of the organism to conduct other processes. Electrogenic bacteria give off their electrons into the soil around them. An MFC captures those lost electrons using electrodes and wire to complete a circuit and generates electrical current. The energy harnessed can then light up a LED, run a clock, thermometer, or any of a number of other things. Electrogenic bacteria can be found naturally in soils all over

Microbial “Trash” is Human Treasure

Microbial “Trash” is Human Treasure

We humans have been treasuring and using microbial “trash” for tens of thousands of years. We eat and nurture microbes for their waste products – yes, you eat microbial poop. Metabolic by-products or “waste” would be more appropriate to say in a classroom/polite company, but really – it’s just “poop”. Yogurt, sauerkraut, buttermilk, kefir, bread, beer, wine, cheese, even chocolate, and coffee – are all tasty to us because microbes have eaten the sugars in milk or some plant part. With the exception of corn, whatever you eat goes into your mouth in one form and comes out the other end in a totally different form. Same with microbes. Bacterial Poop: Sugars to Lactic Acid Bacteria like Lactobacillus sp. eat lactose milk sugars and poop out lactic acid. That’s why unflavored, unsugared yogurt is tangy and slightly sour. Same thing with the buttermilk I’ve been culturing recently. YUMMY. Other Lactobacillus sp. eat plant fiber sugars and poop out lactic acid to make sauerkraut and kimchee. Check out a yogurt experiment my girls and I did a while ago. Yes, the girls roll their eyes when I say that they are eating microbial “trash”. Fungal Farts: Sugars to alcohol and carbon

Foldscope: How Can a Functional Microscope be Made Out of Paper?

Foldscope: How Can a Functional Microscope be Made Out of Paper?

So I keep babbling about Foldscopes because – THEY ARE REALLY COOL! These are out of a Stanford lab developed with funds from the Gates Foundation to help defeat Malaria. As a scientist and mom, there are a trillion things to do with these things. Time and time again, when I talk about these scopes to people I get the same shocked look and question – “How can a PAPER microscope work?” Followed usually by a question on where they can get one for their kid, classroom, science outreach, own backpack/purse. Here’s our experience with the basic Foldscope. Keep in mind, that if you support one of the kits, you get additional accessories. We received the paper scope, lenses, magnetic clips (for cell phone photography), and double stick tape, which is a perfect start. As a certified microbial geek, I had slides and cover slips around the house. Assembly Party We invited a neighborhood friend over for our first “assembly” party. Which was lots of fun! First the girls popped out the scope parts. Watching the assembly video helped us put our scopes together. Differences between Foldscope and Compound Scopes Unlike traditional compound scopes where the lens is in one