SAN FRANCISCO, Nov. 16 (Xinhua) -- Researchers of U.S. Stanford University have discovered new bacteria that were never seen before, which were described as "a dark matter of the biological world," said a study released Thursday.
The two deep lineages of bacteria found in the dolphins' toothy grin are known as phyla, which belong to a broad taxonomic rank that groups together organisms sharing a set of common characteristics due to common ancestry.
The new discovery was revealed in a paper published Thursday by Current Biology, a scientific journal that covers all areas of biology, especially molecular biology, cell biology, genetics, neurobiology, ecology and evolutionary biology.
By studying the new bacteria, which were little known to researchers in the past, scientists may develop new insights into bacterial diversity, dolphin health and the unique nature of marine mammals in general, said David Relman, professor of microbiology and immunology at the Stanford School of Medicine.
The researchers identified the bacterial lineages by reconstructing their genomes from short bits of DNA. The genome of a given cell serves as its blueprint and contains all its operating instructions, encoded in DNA.
One of the newly identified lineages was named Delphibacteria in honor of the dolphins.
The researchers studied the genes encoded in the genomes of Delphibacteria representatives, which may help them open a new window on the bacteria's lifestyle.
The study said the bacteria will express a property called denitrification that may affect dolphins' oral health and the chemical process can cause inflammation in connection with gum disease of dolphins.
"These organisms, about which we have known just a tiny bit, are basically the dark matter of the biological world," Relman said, quoted by the university's press release.
The researchers differentiated between bacteria and observed their behavior by looking broadly at their genomes.
The researchers first cut the DNA into a bunch of little bits and pieces and then the mix of DNA is sequenced, so that they could figure out how the genomes were originally assembled.
Dolphins have long been trained by the U.S. Navy to perform various marine missions, including protecting its ships and submarines and detecting submerged sea mines and underwater intruders.
