How Black Widow's DNA Was Found in New Virus

A new study uncovers a new virus wherein aside from its own gene, and some toxic DNA found in the virus that infects the bacteria, there are also unexpectedly DNA from other animals and a gene for black widow spider venom, Live Science. reported. There are possibilities that the animals have stolen the DNA from the virus or the virus stole the foreign genetic material. Scientists say that it is actually more common that there could be an exchange happening across domains of life and future research can find it.

There are major domains of tree of life: the eukaryotes ---which includes animals, plants, and fungi; prokaryotes, which are single-celled microbes that lack nuclei and are considered as the earliest forms of life. Under prokaryotic, there are two domains. These are what we know as Bacteria, and Archaea, which are microorganisms that flourish in unkind environments such as underground petroleum and hot springs. Normally, a particular virus cannot just get in a certain domain. For example, it is unlikely that viruses that infect bacteria called bacteriophages to infect eukaryotic or cells with nuclei. Previous studies already claimed however that there are some viruses that "stole" genes of the host and use this DNA to dodge and manipulate the victim. There is also another previous study that stated that there are some bacteria that resides in humans and animals such as e.coli, which means it is still possible that the phages can still be in eukaryotic domain.

That is why it is come as a surprise that a DNA of a black widow spider to be found in a certain bacteria. The new study findings in a phage called Wolbachia, a bacterium that infects 40 percent of the species --- such as arthropods which includes crustaceans, insects, and spiders. Wolbachia are one of the most widespread bacterial infections in the planet according to Seth Bordenstein, who is the study co-author and a microbiologist at Vanderbilt University in Tennessee.

Researchers discovered that this particular phage's genomes have number of genes that are also found in eukaryotes. "This is the first time, to the best of my knowledge, that animal genes were found in bacteriophages," Bordenstein told Live Science. These genomes have combination of eukaryotes and bacteria genes. In this combination, it also includes DNA, which was previously found in a study about creation of black widow spider venom.

It is still unknown on how the phages use the genes. Possibilities such as using genes to break in animal cells or dodge the animal's immune system to infect the host. On how the DNA streamed to the phage and animals is another story. It is either the genes in the phage came from animals or that genes of the animals came from the phage.

"We should consider all possible routes of transfer," Bordenstein said.