WASHINGTON, DC – September 29, 2014 -- Plants have a symbiotic relationship with certain bacteria. These ‘commensal’ bacteria help the pants extract nutrients and defend against invaders – an important step in preventing pathogens from contaminating fruits and vegetables. Now, scientists have discovered that plants may package their commensal bacteria inside of seeds; thus ensuring that sprouting plants are colonized from the beginning. The researchers, from the University of Notre Dame, presented their findings today at the 5th ASM Conference on Beneficial Microbes.
WASHINGTON, DC – September 29, 2014 – Bacteria that metabolize ammonia, a major component of sweat, may improve skin health and some day could be used for the treatment of skin disorders, such as acne or chronic wounds. In a study conducted by AOBiome LLC, human volunteers using the bacteria reported better skin condition and appearance compared with a placebo control group. The researchers presented the study results at the 5th ASM Conference on Beneficial Microbes in Washington, DC.
WASHINGTON, DC – September 22, 2014 – Influenza infection can enhance the ability of the bacterium Streptococcus pneumoniae to cause ear and throat infections, according to research published ahead of print in the journal Infection and Immunity.
Critically Ill ICU Patients Lose Almost All of Their Gut Microbes—And The Ones Left Aren’t The Good Guys
WASHINGTON, DC—September 23, 2014—Researchers at the University of Chicago have shown that after a long stay in the Intensive Care Unit (ICU) only a handful of pathogenic microbe species remain behind in patients’ intestines. The team tested these remaining pathogens and discovered that some can become deadly when provoked by conditions that mimic the body’s stress response to illness.
WASHINGTON, DC –September 16, 2014 – The specific composition of bacterial species in a person’s gut may protect against or increase susceptibility to Campylobacter, the most common cause of human bacterial intestinal inflammation, according research published this week in mBio®, the online open-access journal of the American Society for Microbiology. The study also found that Campylobacter infection can yield lasting changes to one’s gut bacteria composition.
“It has been known for a long time that the microbiota, or microorganisms in the gut, can protect a person from colonization by organisms that cause intestinal tract disease. However, very little is known about how human gut microbiota influences susceptibility to these organisms, and to Campylobacter in particular,” said senior study author Hilpi Rautelin, MD, PhD, professor of clinical bacteriology at Uppsala University and Uppsala University Hospital in Sweden. “We wanted to see if the composition of the human gut microbiota plays a role in susceptibility to Campylobacter infection.”
Rautelin and colleagues followed 24 workers at three poultry slaughterhouses in Sweden. In 2010, they collected fecal samples from the workers once a month from June to September, during the summer peak of Campylobacter-positive chicken flocks, and again the following February. Fecal samples were cultured for Campylobacter and analyzed by sequencing for all bacteria. While all participants tested negative for Campylobacter at the beginning of the study, seven participants became culture positive for the organism during the study. Only one of the Campylobacter-positive participants experienced symptoms of illness.
Those who became Campylobacter-positive had a significantly higher abundance of Bacteroides and Escherichia organisms than those who remained culture negative, suggesting that these bacterial species likely play an important role in colonization resistance. This group also had a significantly higher abundance of Phascolarctobacterium and Streptococcus species than those in the Campylobacter-negative group, which had an overrepresentation of Clostridiales, unclassified Lachnospiraceae, and Anaerovorax species.
“Elevated proportions of Bacteroides and Escherichia species in the gut microbiota may predispose humans to Campylobacter infection,” Rautelin said. “These particular species have been shown to have an important role for susceptibility to gut pathogens and Campylobacter in particular in some mouse model studies.”
Following the individuals’ fecal microbiota compositions over time, the researchers observed that the Campylobacter-negative individuals had small differences but those who tested positive for Campylobacter showed significant changes by the February sample. Researchers do not yet know the implications of these changes, Rautelin said.
Whether microbiota composition alone or together with an individual’s immune status also plays a significant role in the eradication of Campylobacter from the intestines remains to be studied, she said.
The study was supported by the Swedish Research Council, the Swedish Research Council FORMAS, and the Söderbergs Foundation.
The article can be found online at http://bit.ly/asmtip0914e.
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mBio® is an open access online journal published by the American Society for Microbiology to make microbiology research broadly accessible. The focus of the journal is on rapid publication of cutting-edge research spanning the entire spectrum of microbiology and related fields. It can be found online at http://mbio.asm.org.
The American Society for Microbiology is the largest single life science society, composed of over 39,000 scientists and health professionals. ASM's mission is to advance the microbiological sciences as a vehicle for understanding life processes and to apply and communicate this knowledge for the improvement of health and environmental and economic well-being worldwide.