A paper in Sexually Transmitted Infections details a cheap way to kill off gonorrhea in the mouth - alcohol-containing mouthwash. 

Gonorrhea is caused by bacteria and  curb the growth of the bacteria responsible.  Gonorrhea of the mouth has become more common among primarily gay men as fear of AIDS has declined. That disease is quite treatable today and so fear of it has declined, meaning a decline in condom use.

Gonorrhea is also treatable, with antibiotics, but those heighten the risk of the emergence of antibiotic resistant strains of Neisseria gonnorheae, the bacteria responsible for the infection, so concern is high.

If gay men won't use condoms, maybe they'll use mouthwash
A new paper links specific types of intestinal bacteria in the development of colorectal cancer - in animal models, at least. Finding it in humans is another matter.

But if such a link is ever found, and currently these findings are only exploited by people selling something, it could lead to dietary-based therapeutic interventions which may be able to modify the composition of the gut microbiome and reduce colorectal cancer risk.
Thanks to savvy marketing by food corporations who are looking for health halos to put over their food, consumer demand for food products formulated without synthetic additives has increased.

There is a big drawback, demonstrated by Chipotle and others who are hoping to make themselves look healthier when selling junk food - it still has to be safe to eat. Additives, synthetic or not, are needed for food safety reasons, so food product developers are faced with the challenge of developing more "natural" additives that can produce comparable in safety results with synthetic versions. 

Pigs are a main livestock species for food production worldwide and is also widely used as an animal model in biomedical research. Today we know that the many types of bacteria that inhabit the gut are important for health and disease. Knowledge of the genes of these bacteria and their function therefore constitutes the first step towards a more comprehensive understanding of how bacteria in the gut affect health and disease.

An international consortium of researchers from INRA (France), University of Copenhagen and SEGES (Denmark), BGI-Shenzhen (China) and NIFES (Norway) has now established the first catalog of bacterial genes in the gut of pigs. This achievement is published in the latest issue of Nature Microbiology.

Researchers have found an association between migraines and microbes that reduce nitrates. Analyzing data from the American Gut Project, they found that migraine sufferers harbored significantly more microbes in their mouths and guts with the ability to modify nitrates compared to people who do not get migraine headaches. 
The bacterium that causes citrus greening disease, Candidatus Liberibacter asiaticus (CLas), is not only decimating citrus orchards, it also does a number in the guts of the insect that transmits it.

Citrus greening disease, also called Huanglongbing, has taken a terrible toll on Florida's $9 billion citrus industry and infected trees have already been detected in California. It is vector-borne, which means it is spread by insects, namely the Asian citrus psyllid. 
Nestle, the world's largest food company, has decided to embrace optimizing our microbiome, which consists of trillions of bacteria living in the digestive system and which has been linked to depression, multiple sclerosis, autism - you name it, and someone is claiming their product will fix it.

 Microsporidia are typically found in the intestinal tracts of animals and humans, which are made up of millions of cells, which is why studying their mode of reproduction has been so difficult. Yet it's important. Microsporidia cause diarrhea, an illness called microsporidiosis, and even death in immune-compromised individuals.

In spite of those known widespread medical problems, scientists were uncertain about how these single-celled fungi reproduced in human or animal cells. In a study that employed transparent roundworms, biologists at the University of California San Diego succeeded in directly observing how these microorganisms replicate and spread. And what they saw surprised them.

Bacteria transfer to candy that has fallen on the floor no matter how fast you pick it up.  

Rutgers researchers have disproven the widely accepted notion that it's OK to scoop up food and eat it within a "safe" five-second window. Donald Schaffner, professor and extension specialist in food science, found that moisture, type of surface and contact time all contribute to cross-contamination. In some instances, the transfer begins in less than one second. Their findings appear online in the American Society for Microbiology's journal, Applied and Environmental Microbiology.

You recently saw how a build-up of microbes in bagpipes recently doomed a Scottish man. That could apply to all wind instruments, and a U.S. Food and Drug Administration microbiologist warns that several species of bacteria found in smokeless tobacco products have been associated with opportunistic infections.

Obviously that doesn't mean they caused them but associations are important in making health policy, and alternatives to cigarette smoking, in the interests of harm reduction and smoking cessation, are controversial, with the U.S. government being squarely against them, a legacy of the 'quit or die' mentality that has keep cigarette smoking as (not very) popular that it is.