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The Hawaiian Bobtail squid has a remarkable symbiotic relationship with a species of marine bacteria that can produce light by a controlled chemical reaction. Also featured on the HHMI DVD, Exploring Biodiversity: The Search for New Medicines, available free from HHMI.

Human and animal disease are often caused by viruses or bacteria. Over the past two hundred or so years, vaccines have eradicated some of these diseases. Others have returned to haunt humans with new and ever-mutating strains. Communicable diseases may spread in different ways: through blood, air, feces/urine, food, or water. The World Health Organization (WHO) and the Center for Disease Control (CDC) keep constant watch over the most potentially dangerous diseases and the most likely threats to various world populations.

7:00 video: This film is the first of a two part series on the evolution of new genetic information. Here we focus on Point Mutations - the simplest natural mechanisms known to increase the genetic information of a population. Our second film of the series will focus on duplication events - natural mutations that increase the total amount of genetic information of an individual. This film was produced under the guidance of molecular biologist Dr. Nicholas Casewell. http://www.lstmed.ac.uk/about/people/... Point mutations are small, natural edits in the DNA code of an individual. These edits can be passed from parent to child. Because they are mere edits, point mutations usually do not increase the total amount of information in an individual. As new information is gained, old information is lost. Point mutations do, however, increase the total amount of information within a population. In this film you will see several examples of beneficial point mutations which have enhanced a creatures abilities or even given rise to entirely new abilities. The first two examples were directly observed in bacteria by scientists in the lab. The third is a case found in domestic dogs, the last example was discovered in several species of wild animal.

7:23 video Are we entering the post-antibiotic era? Antibiotic-resistant bacteria are on the rise, with millions of infections reported every year and thousands of deaths. How does antibiotic resistance work? How did we get here? And what can we do in the future to make sure that papercuts don't spell a death sentence?

Our bodies are home to approximately 100 trillion bacteria living inside us and on us-a vast community known as the microbiome. The Secret World Inside You explores the rapidly evolving science that is revealing the complexities of the human microbiome and reshaping our ideas about human health, offering new perspectives on common health problems including allergies, asthma, and obesity. 

2:21 video New research on mice demonstrates a way to use designer bacteria as a non-invasive test for cancer.

Behind every fart (and poop) is an army of gut bacteria undergoing some crazy (and crazy useful) biochemistry. Learn what they have in common with beer brewing, and why we'd want to know about this science anyway...

12 minute video

Dubilier is hardly alone in her plight. A heaping teaspoon of soil or a shot of ocean water may contain as many as one million bacterial species. Many of them are potential gold mines of chemicals and metabolites with medicinal, engineering, and energy applications. But when researchers have tried to culture these microbes in the lab, only a minority of cells form colonies. Clearly, nutrients, a carbon source, and time are usually not enough to coax bacteria isolated from the wild to grow in a laboratory setting. So what's the missing ingredient?

Discover natural selection as a mechanism of evolution with the Amoeba Sisters. This video also uncovers the relationship of natural selection and antibiotic resistance in bacteria.

Discover natural selection as a mechanism of evolution with the Amoeba Sisters. This video also uncovers the relationship of natural selection and antibiotic resistance in bacteria.

In recent years, Claverie and his colleagues have discovered a host of giant viruses, which are as big as bacteria but lack characteristic cellular machinery and metabolism of those microorganisms. At least one family of these viruses likely evolved from single-celled parasites after losing essential genes, although the origins of other giant viruses remain a mystery, Claverie said.

The club, which has about 20 members, is researching the culture and regrowth of methanotrophic bacteria, using a wide variety of experiments and individual projects. The students meet every Thursday with their advisor, Michael Ralph, and they also work during their own time.

GMOs are organisms that have had their DNA modified through genetic engineering. This is often done by taking a gene from one organism and putting it into another one to alter it in a desirable way. For example, when genetic engineers want to create a corn crop that is resistant to pests, they seek out the trait in Bacillus thuringiensis (Bt) soil bacteria that naturally acts as a pesticide. From there, engineers isolate the gene responsible for that trait and directly insert it into the corn's DNA. This corn is then bred with other corn until it's ready to be produced for consumption.

In 1674, Antonie van Leeuwenhoek looked at a drop of lake water through his homemade microscope and discovered an invisible world that no one knew existed. His work inspired countless microbiology researchers, including HHMI investigator Bonnie Bassler, one of the narrators of this animated feature. Leeuwenhoek was a haberdasher and city official in Delft, The Netherlands. He started making simple microscopes and using them to observe the world around him. He was the first to discover bacteria, protists, sperm cells, blood cells, rotifers, and much more. 

When an elementary school teacher calls in sick to work, she finds out that she is not the only one who will be missing school that day.  Children from her fifth grade class have also become ill and parents are calling to report the absences. The concerned principal of the school finds out the fifth grade class had a field trip to one of the local parks the day before. The case shows the areas visited by the class and provides discussion between the principal and a physician that teaches the readers about water quality and EPA standards for bacteria levels in recreational water. The case has an optional lab component that provides the theory for three methods that can be used to conduct microbial water analyses.  Procedures are included for teachers to lead a lab activity to test water to identify which location in the park caused the illness. This case study and accompanying laboratory activity are recommended for an environmental engineering course or a lower level science course.

Iona Twaddell looks at the science of the waterborne disease cholera There are an estimated 3-5 million cases of cholera, a disease caused by the bacterium Vibrio cholera, each year. It is passed on through drinking water that has been contaminated with faeces from someone infected with the bacteria. Cholera causes vomiting and diarrhoea, leading to severe dehydration.

Brain-eating amoebas (Naegleria fowleri) are found in warm freshwater pools around the world, feeding on bacteria. If someone swims in one of these pools and gets water up their nose, the amoeba heads for the brain in search of a meal. Once there, it starts to destroy tissue by ingesting cells and releasing proteins that make other cells disintegrate.

10:04 video, Don't panic! But you should really know about antibiotic-resistant bacteria, aka super bugs. They're here, and they're doing very well, thank you. SciShow explains what they are, how they're getting around our best drugs, and what science (and you) can do to help.