NEW BRUNSWICK, NJ - It is not the easiest thing to get, and something the average person has never thought about, but scientists have found a medical value in, of all things, saliva from East Siberian brown bears.
Scientists from Rutgers, working with others in the field, have used bacterium from the wild animals to see if it inhibits harmful bacteria, according to study published online in the Proceedings of the National Academy of Science.
“We swiftly determined the spectrum of the antibiotic activity in saliva from a Siberian bear,” said Konstantin Severinov, a co-author of the study and professor of molecular biology and biochemistry at Rutgers-New Brunswick.
Researchers wanted a bear caught in the wild, Severinov said, to show diversity of bacteria depends on diet. That diversity, he said, "decreases dramatically, for example, in zoo-kept animals or urban humans compared with people from indigenous tribes."
“The bear was chosen largely because it was captured way out in the wilderness where, it was assumed, microbes typical for the species and not affected by civilization are present,” Severinov said.
Microbes in wild animals or other exotic sources are a largely unexplored area in the search for antibiotics. Researchers suspect the microbiota in wild animals may help protect them from the aggressive microbes that surround them.
Bacterium from a wild animal’s mouth was used in an oil droplet to see if it inhibits harmful bacteria, such as Staphylococcus aureus, which is a common cause of serious skin rashes and respiratory diseases, including pneumonia.
In this study, a bear was caught in the wild, a saliva sample was taken and the animal was released, according to the Rutgers officials.
Machines were used to rapidly sort several hundred thousand oil droplets with bacteria from the bear’s mouth, and the scientists found one droplet with zero Staphylococcus aureus. The beneficial strain of bacteria that killed Staphylococcus aureus produces a previously known antibiotic, called amicoumacin, according to the study.
“It is tedious to look for bacteria that produce antibiotics by testing them on Petri dishes and looking at how they inhibit the growth of harmful bacteria,” said Severinov, who is also a principal investigator at Rutgers' Waksman Institute of Microbiology.