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Life on Earth is intimately connected to the natural cycles of light and dark that make up a 24-hour day. For plants, animals, and even bacteria, these circadian rhythms control many biological functions. Humans can overrule their body clocks, but at a price: People whose circadian rhythms are regularly disrupted-by frequent jet lag or shift work, for example-are more vulnerable to diabetes, obesity, cardiovascular disease, and cancer. There are various theories to explain these associations, and researchers now have a new player to consider: the bacteria that live in the digestive tract. According to a study in mice and a small group of human volunteers, the internal clocks of these gut microbes sync up with the clocks of their hosts. When our circadian rhythms get out of whack, so do those of our bacteria.

Men shed more bacteria into their surroundings than women do, studies have shown. Now scientists have found that men and women have different effects on the variety of bacteria inside a home, too. The variation comes down to skin biology and "perhaps to body size and hygiene practices," note researchers who sequenced the genes in dust that had settled on the tops of doors in 1,200 homes across the U.S. Dogs apparently alter indoor bacteria more extensively than humans or cats. The bacterial signatures of each of these living beings are unique enough that by simply testing dust in a home, investigators can accurately predict if more women or men live there and if dogs or cats do as well.

Biologists at the Massachusetts Institute of Technology have created a genetically modified version of a common bacteria found in the gut that can sense the environment there and fight disease. And when this designer bacteria works, the proof is in the poop - glowing poop. (In this case, mouse poop.)

Deadly bacteria are spreading through the oceans as waters warm up, and are increasing infection risks, according to a new study. Multiple species of rod-shaped Vibrio bacteria live in the world's oceans, and their populations rise and fall based on many different variables, changing the likelihood of making people sick.

This interrupted case study introduces the topic of bacterial sporulation and cannibalism in Bacillus subtilis. The storyline follows Susan and her lab mates who are presenting research at a lab meeting when Susan falls asleep and dreams they are stranded on a deserted island. She makes connections between their fight for survival in the dream and the survival mechanisms of the bacteria they study in the lab. The benefits of sporulation under conditions of sustained stress are fairly obvious, but Susan's dream is used to examine the idea that sporulation may not always be beneficial and that bacteria would not want to commit to entering such a state in response to temporary stresses. Through the analysis of actual data from the scientific literature, students uncover a mechanism by which B. subtilis delays its commitment to sporulation by killing members of its own species to release nutrients (i.e., cannibalism). Originally developed for a general undergraduate microbiology course when discussing the structure and growth of prokaryotic cells, the case could also be used in an introductory biology course that emphasizes bacteria and data literacy.

Bonnie Bassler discovered that bacteria "talk" to each other, using a chemical language that lets them coordinate defense and mount attacks. The find has stunning implications for medicine, industry -- and our understanding of ourselves. Bonnie Bassler studies how bacteria can communicate with one another, through chemical signals, to act as a unit. Her work could pave the way for new, more potent medicine.

UCLA researchers now have the first evidence that bacteria ingested in food can affect brain function in humans. In an early proof-of-concept study of healthy women, they found that women who regularly consumed beneficial bacteria known as probiotics through yogurt showed altered brain function, both while in a resting state and in response to an emotion-recognition task.

"We risk being in a post-antibiotic world," said Thomas Frieden, director of the U.S. Centers for Disease Control and Prevention, referring to the urinary tract infection of a 49-year-old Pennsylvania woman who had not traveled within the prior five months. Frieden, speaking at a National Press Club luncheon in Washington, D.C., said the bacteria was resistant to colistin, an antibiotic that is reserved for use against "nightmare bacteria."

Using bacteriophages to deliver a specific CRISPR/Cas system into antibiotic-resistant bacteria can sensitize the microbes to the drugs, according to a study published this week (May 18) in PNAS.

In a creative stroke inspired by Hollywood wizardry, scientists from Harvard Medical School and Technion-Israel Institute of Technology have designed a simple way to observe how bacteria move as they become impervious to drugs. The experiments, described in the Sept. 9 issue of Science, are thought to provide the first large-scale glimpse of the maneuvers of bacteria as they encounter increasingly higher doses of antibiotics and adapt to survive - and thrive - in them.

Engineers at MIT and the University of California at San Diego (UCSD) have devised a new way to detect cancer that has spread to the liver, by enlisting help from probiotics - beneficial bacteria similar to those found in yogurt.

informative site on wide array of topics about bacteria including articles and case studies

Your mother's DNA may have determined your eye color, but some traits that you thought came from her may instead have come from the DNA of bacteria she passed on to you soon after birth, a new study finds. The study found that a mother mouse can pass along to her offspring a susceptibility to intestinal disorders, such as inflammatory bowel disease, by way of a gut-residing bacterium called Sutterella, the researchers reported in the journal Nature on Feb. 16.

4:34 video Right now, you are inhabited by trillions of microorganisms. Many of these bacteria are harmless (or even helpful!), but there are a few strains of 'super bacteria' that are pretty nasty -- and they're growing resistant to our antibiotics. Why is this happening? Kevin Wu details the evolution of this problem that presents a big challenge for the future of medicine.

Want to know how much bacteria we host within our body and how many we encounter on a daily basis well check out this clip from Life On Us where we will see the different types of bacteria that inhabit us like Demodex Folliculorum which is a face mite...

Most colon cancers may be caused by infections with bacteria that are normally found in cows. For decades we have known that Streptococcus gallolyticus gallolyticus (SGG) is sometimes found in colon tumours, but now the microbes have been found to directly cause tumour growth in mice.

This case study centers on symbiotic relationships between insects and bacteria using Drosophila melanogaster, the common fruit fly, and the recently discovered bacterial species Sodalis praecaptivus. Until recently, the only known Sodalis species of bacteria were symbiotically associated with several different species of insects. However, free-living non-symbiont Sodalis species are being tested in several different insect species to determine if they can transition into symbiotic relationships. A pre-class assignment (see Supplemental Materials) directs students to read an open access research journal article providing a comprehensive review of S. praecaptivus and describing an experimental weevil model that parallels that of the fruit fly. A PowerPoint presentation shown in class (see Supplemental Materials) provides further background before students work in small groups to complete the case study focusing on results from D. melanogaster and S. praecaptivus model experiments.  Although developed for a genetics course, this interrupted case is appropriate for an upper-level biology course. It can be completed within a 75-minute class meeting, or adapted for shorter time periods.

We are under attack - by germs. Drug-resistant bacteria are invading organisms, and hospitals are their favorite breeding ground. Scientists are studying the genetics of bacteria and trying to find

Scientists have confirmed that the pathogen that causes Lyme Disease -- unlike any other known organism -- can exist without iron, a metal that all other life needs to make proteins and enzymes. Instead of iron, the bacteria substitute manganese to make an essential enzyme, thus eluding immune system defenses that protect the body by starving pathogens of iron.

Department of Defense researchers disclosed Thursday in a report placed online by the journal Antimicrobial Agents and Chemotherapy that a 49-year-old woman who sought medical care at a military-associated clinic in Pennsylvania last month, with what seemed to be a urinary tract infection, was carrying a strain of E. coli resistant to a wide range of drugs. That turned out to be because the organism carried 15 different genes conferring antibiotic resistance, clustered on two "mobile elements" that can move easily among bacteria. One element included the new, dreaded gene mcr-1.