Navigation Links
Bacteria have their own immune system protecting against outside DNA

Bacteria like Salmonella have a complicated immune system that helps them recognize and isolate foreign DNA trying to invade their cell membrane, according to a University of Washington-led study in the June 8 issue of Science Express. The research, which also included scientists at the Sidney Kimmel Cancer Center in San Diego, could have major implications for understanding the evolution of disease-causing bacteria. The findings may also impact the biotech industry, where bacteria are used to produce recombinant human proteins for medical treatments and research.

A group of researchers led by Dr. Ferric Fang, professor of laboratory medicine and microbiology at the UW School of Medicine, were interested in learning how bacteria respond to genetic information coming from outside sources. Just as immune cells recognize and attack foreign invaders in the human body to protect against harmful infections, single-cell organisms have a protein called H-NS that recognizes foreign DNA and prevents it from becoming active, the researchers discovered.

But bacteria can also benefit from foreign DNA. When Salmonella is infecting an animal or person, for instance, many proteins the bacteria need to cause disease are encoded by DNA acquired from other bacteria. The researchers found that when the bacteria is infecting a host, other molecules can compete with the H-NS protein, allowing the disease-causing genes to be expressed. When the bacteria are in the environment, H-NS turns these genes off to avoid detrimental consequences if all the disease-causing genes were to be expressed at once.

These findings give scientists new insight into how bacteria can protect themselves from an invasion by foreign DNA, yet still take in genetic information from diverse sources that makes them more virulent.

"By harnessing foreign DNA, bacteria that cause typhoid, dysentery, cholera and plague have evolved from harmless organisms into feared pathogens," explained Dr. William Navarre, a senior fellow at the UW and primary author of the study. "This research gives us an explanation of how pathogenic bacteria have evolved over millions of years."

The researchers also learned that the H-NS protein is able to recognize foreign DNA on the basis of its increased content of adenine and thymine, the building blocks of DNA.

"It has been a great mystery why disease-causing genes of bacteria usually contain more adenine and thymine," said Michael McClelland, professor and director of the Molecular Biology Program at the Kimmel Cancer Center. "Now we know this is because such sequences are easier to recruit and regulate than other DNA."

This research could also have major implications for the biotech industry, which uses bacteria for the production of recombinant proteins for medicine and research. These proteins, such as insulin or human growth hormone, are created when a piece of human DNA corresponding to that protein is introduced into bacteria. The bacteria then reproduce many times over, creating more of the protein each time they reproduce. The proteins are purified out from the bacteria, leaving behind only the useful protein. However, in that process, the yield of some human proteins produced in bacteria can be low. The new research indicates that the H-NS "immune system" may be responsible for interfering with the expression of human genes in bacteria.

"Having a better understanding of this system could help the biotech industry make recombinant proteins more efficiently," said Fang. "More foreign protein can be produced in bacteria that don't have the H-NS molecule."


'"/>

Source:University of Washington


Related biology news :

1. Bacteria collection sheds light on urinary tract infections
2. Solution to Pollution: New Bacteria Eats Toxic Waste
3. The Bacterias guide to survival
4. UF Researchers Map Bacterial Proteins That Cause Tooth Loss
5. Bacterial genome sheds light on synthesizing cancer-fighting compounds
6. Where Bacteria Get Their Genes
7. Bacteria feed on smelly breath (and feet)
8. New insight into autoimmune disease: Bacterial infections promote recognition of self-glycolipids
9. Bacteria use hosts immune response to their competitive advantage
10. Say what? Bacterial conversation stoppers
11. Bacteria are key to green plastics, drugs
Post Your Comments:
*Name:
*Comment:
*Email:


(Date:12/15/2016)... , Dec. 14, 2016 "Increase in mobile ... market" The mobile biometrics market is expected to grow ... billion by 2022, at a CAGR of 29.3% between ... such as the growing demand for smart devices, government ... "Software component is expected to grow at ...
(Date:12/7/2016)... 2016 According to a new market research report "Emotion ... Expression, Voice Recognition), Service, Application Area, End User, And Region - Global Forecast ... USD 6.72 Billion in 2016 to USD 36.07 Billion by 2021, at a ... Reading ... MarketsandMarkets Logo ...
(Date:12/6/2016)... , Dec. 6, 2016  Zimmer Biomet Holdings, Inc. ... has priced an offering of €500.0 million principal amount of ... principal amount of its 2.425% senior unsecured notes due 2026. ... to occur on December 13, 2016, subject to the satisfaction of ... annual basis. The Company intends ...
Breaking Biology News(10 mins):
(Date:1/18/2017)... ... 18, 2017 , ... uBiome, the leading microbial genomics company, ... Editor, Dr. Elisabeth Bik, in the December 2016 issue of the Dutch Journal ... October 2016 from her previous position at Stanford University School of Medicine and ...
(Date:1/18/2017)... Texas , Jan. 18, 2017  Caris ... and the Lustgarten Foundation, the largest private funder ... a clinical trial evaluating the impact of immunotherapy ... providing clinical trial enrollment services to identify potential ... facilitate communication between treating physicians and study investigators. ...
(Date:1/17/2017)... ... 17, 2017 , ... MS Technologies™ and Bayer have received ... Performance System will combine industry-leading genetics with a double herbicide-tolerant trait that will ... Bean herbicide. The Balance™ GT Soybean Performance System will benefit soybean growers by ...
(Date:1/17/2017)... WARSAW, Ind. , Jan. 17, 2017  Zimmer ... its fourth quarter and full-year 2016 sales and earnings ... on Tuesday, January 31, 2017, at 8 a.m. Eastern ... results will be made available at 7:30 a.m. Eastern ... The live audio webcast can be accessed via Zimmer ...
Breaking Biology Technology: