Microbiomes

Spring 2018

Do microbes dream of circadian sleep?

Anticipation is sweet. In anticipation of the blooming light, plants unfurl their leaves. For many marine creatures, rising to the sea surface as the moon rises is the anticipatory signal that food is available. In our gut, too, microbes anticipate dinnertime because microorganisms have internal clocks that sound the dinner bell.

“And here’s where it gets interesting,” says Hans Van Dongen, a professor of psychology at Washington State University Spokane and internationally known sleep expert.

“The biological clock those organisms have and the brain-based clock that humans have are not necessarily in sync. You notice this when you travel to another time zone. … » More …

Winter 2017

A mother’s microbial gift

Old assumptions about human breast milk are giving way to new thinking about microbes in milk and their role in children’s health and our immune systems.

It happened again, most recently at a conference in Prague. After she gave her talk, a scientist came up to Shelley McGuire, a pioneer exploring the microbial communities found in human breast milk, and told her, You don’t know how to take a sample. Your samples must have been contaminated. Human milk is sterile.

McGuire, a professor of human nutrition at Washington State University, knows differently: She’s seen the microbes with her own eyes. But she understands … » More …

Winter 2017

The microbe whisperers

Tarah Sullivan is fiercely insistent that we are all interconnected. The Washington State University soil microbiologist and ecologist says that understanding those connections is key to a healthy future.

“I know it sounds a little hokey,” the mother of two daughters apologizes without backing down: “Microorganisms connect everything everyday in every way. We absolutely could not survive on the planet without active and healthy microbiomes, in humans and in the environment.”

Sullivan’s work focuses on how microbial communities in soil impact heavy metal biogeochemistry. Many metals are important micronutrients for both plants and animals—but too much of a good thing can make plants sick. … » More …

Winter 2017

What’s that bacteria? Check the 16S

There are millions of microorganisms in a drop of pond water—but who are they? There are bacteria, protozoa, hydras, arthropods—all manner of critters are in that drop of water. Dividing them up by genera and species, though, is tricky because many bacteria look similar. That makes identifying the members of a microbial community difficult.

A new way of identifying microbes is with the tools of the genomicist. Just as we can sequence the genome of a single organism, so too can we now sequence a drop of pond water, kefir, milk, or fecal material to see who lives there.

Researchers look at a particular gene, … » More …

Winter 2017

The secrets in a tick’s gut

It may be possible to use good bacteria to control bad bacteria and, in the process, reduce the use of chemicals currently employed for such control. Just look in a tick’s gut.

Kelly Brayton, a WSU veterinary microbiologist, and her colleagues study the pathogens in ticks that cause disease in livestock and humans. The pathogens infest ticks’ guts and salivary glands and, along with other non-pathogenic organisms, comprise the tiny arachnid’s microbiome.

They’ve recently been studying something fascinating: If a tick is infected by a non-disease causing strain of the bacteria Anaplasma marginale, its bite won’t transmit anaplasmosis to its human victim. This “exclusion process,” … » More …