Predatory Bacteria Found in Spanish Study of Cystic Fibrosis Lung Micro-organisms

Scientists have known for some time that cystic fibrosis patients have a variety of bacteria in their lungs.

Researchers in Madrid have discovered two unusual predatory bacteria in a study investigating lung micro-organisms.

Their study, “Individual Patterns of Complexity in Cystic Fibrosis Lung Microbiota, Including Predator Bacteria, over a 1-Year Period,” was published in mBio, the American Society for Microbiology’s online open-access journal.

The team analyzed the bacterial makeup of 56 sputum samples provided by 15 CF patients. They found 156 types of bacteria, including Burkholderia, Pandorea, Pseudomonas aeruginosa and Staphylococcus aureus.

Remarkably, the team discovered two types of predatory bacteria that have never been reported in CF.

One was Vampirovibrio, a bacterium that destroys cells by sucking out what’s inside. The other was  Bdellovibrio, which enters cells to feed on their proteins.

Scientists have dubbed such bacteria predators because they feed on other cells.

The researchers found Vampirovibrio in 17 samples from 12 patients. The team collected the samples three to four times over a year.

Bdellovibrio was less common, being detected in six samples from three patients. The two types of bacteria were found together in only one patient.

The findings surprised the team. They hypothesized that in the early stages of CF, the predators might help prevent colonization by bacteria like P. aeruginosa, which is typically associated with the disease.

Predator bacteria “are ubiquitous and usually found in environmental aquatic ecosystems,” Rosa del Campo, senior author of the study, said in a press release. “In humans, a recent study has found them in the intestinal microbiota of healthy individuals and in patients with cystic fibrosis.”

The results suggested that the lung microbiota in CF is more complex than previously thought and could be used as a pathway to treatments.

“Our study suggests that predatory bacteria could be used as a therapeutic strategy to reduce the bacterial load of the lungs of these patients,” del Campo said.

The team plans to cultivate the predator bacteria in a lab to understand how they survive in the lungs and how they interact with the bacteria they prey on. The next step would be to use the predator-prey dynamics to try to control the lung microbiota in CF.