A vampire-like bacteria that leeches¹ onto（对……纠缠不休） specific other bacteria -- including certain human pathogens -- has the potential to serve as a living antibiotic² for a range of infectious diseases, a new study indicates. The bacterium³, Micavibrio aeruginosavorus, was discovered to inhabit wastewater nearly 30 years ago, but has not been extensively studied because it is difficult to culture and investigate using traditional microbiology techniques. However, biologists in the University of Virginia's College of Arts & Sciences, Martin Wu and graduate student Zhang Wang, have decoded⁵ its genome and are learning "how it makes its living," Wu said.

The bacterium "makes its living" by seeking out prey⁶ -- certain other bacteria -- and then attaching itself to its victim's cell wall and essentially⁷ sucking out nutrients⁸. Unlike most other bacteria, which draw nutrients from their surroundings, M. aeruginosavorus can survive and propagate（繁殖） only by drawing its nutrition from specific prey bacteria. This kills the prey -- making it a potentially powerful agent for destroying pathogens.

One bacterium it targets is Pseudomonas aeruginosavorus, which is a chief cause of serious lung infections in cystic fibrosis（囊胞性纤维症） patients.

"Pathologists may eventually be able to use this bacterium to fight fire with fire, so to speak, as a bacterium that will aggressively hunt for and attack certain other bacteria that are extremely harmful to humans," Wu said.

His study, detailing the DNA⁹ sequence of M. aeruginosavorus, is published online in the journal BMC Genomics. It provides new insights to the predatory lifestyle of the bacterium and a better understanding of the evolution of bacterial¹⁰ predation in general.

"We used cutting-edge genomic technology in our lab to decode⁴ this bacterium's genome," Wu said. "We are particularly interested in the molecular¹² mechanisms¹³ that allow it to hunt for and attack prey. This kind of investigation¹⁴ would have been extremely difficult and expensive to do only a few years ago."

He noted¹⁵ that overuse of traditional antibiotics¹⁶, which work by either inhibiting¹⁷ bacteria propagation or interfering¹⁸ with cell wall formation, are creating so-called "super bugs¹⁹" that have developed resistances to treatment strategies. He suggests that new approaches are needed for attacking pathogens without building up their resistance.

Additionally, because M. aeruginosavorus is so selective a feeder, it is harmless to the thousands of beneficial bacteria that dwell in the general environment and in the human body.

"It is possible that a living antibiotic such as M. aeruginosavorus -- because it so specifically targets certain pathogens -- could potentially reduce our dependence²⁰ on traditional antibiotics and help mitigate²¹ the drug-resistance problem we are now facing," Wu said.

Another benefit of the bacterium is its ability to swim through viscous²²（粘性的） fluids, such as mucus. P. aeruginosavorus, the bacterium that colonizes²³ the lungs of cystic fibrosis patients, creates a glue-like biofilm, enhancing its resistance to traditional antibiotics. Wu noted that the living cells of M. aeruginosavorus can swim through mucus（黏液） and biofilm and attack P. aeruginosavorus.

M. aeruginosavorus also might have industrial uses, such as reducing bacteria that form biofilms in piping, and for medical devices, such as implants²⁴ that are susceptible²⁵ to the formation of biofilms.

Wu said M. aeruginosavorus requires further study for a more thorough understanding of its gene¹¹ functions. He said genetic²⁶ engineering would be required to tailor the predatory attributes of the bacterium to specific uses in the treatment of disease.

"We have a map now to work with, and we will see where it leads," he said.

Wu and Wang's co-author is Daniel E. Kadouri, a researcher at the New Jersey²⁷ Dental School. Kadouri is interested in M. aeruginosavorus as an agent for fighting oral biofilms, such as plaque²⁸（血小板） .