Scientists identify a unique combination of bacterial strains that could treat antibiotic-resistant gut infections

Good news! Perhaps a good mixture of bacteria ("commensal consortia") is more effective!

"Antibiotic-resistant bacterial infections often occur in patients with chronic inflammatory intestinal conditions, such as inflammatory bowel disease, and in patients who have taken antibiotics for a long time. Gram-negative bacteria such as Enterobacteriaceae are a common cause of these infections and have few treatment options. ... 

Fecal microbiota transplants have shown promise to curb some of these infections, but their composition varies between batches and they aren’t always successful.

Researchers ... have isolated 18 bacterial strains from stool from healthy people that could potentially be a more effective treatment. The team found that these strains suppress the growth of Enterobacteriaceae and alleviate inflammation in the guts of mice by competing with the harmful bacteria for carbohydrates and preventing them from colonizing the intestine.  ...

“Despite two decades of microbiome research, we are just beginning to understand how to define health-promoting features of the gut microbiome,”  ..."

From the abstract:

"Persistent colonization and outgrowth of potentially pathogenic organisms in the intestine can result from long-term antibiotic use or inflammatory conditions, and may perpetuate dysregulated immunity and tissue damage. Gram-negative Enterobacteriaceae gut pathobionts are particularly recalcitrant to conventional antibiotic treatment, although an emerging body of evidence suggests that manipulation of the commensal microbiota may be a practical alternative therapeutic strategy. Here we isolated and down-selected commensal bacterial consortia from stool samples from healthy humans that could strongly and specifically suppress intestinal Enterobacteriaceae. One of the elaborated consortia, comprising 18 commensal strains, effectively controlled ecological niches by regulating gluconate availability, thereby re-establishing colonization resistance and alleviating Klebsiella- and Escherichia-driven intestinal inflammation in mice. Harnessing these activities in the form of live bacterial therapies may represent a promising solution to combat the growing threat of proinflammatory, antimicrobial-resistant Enterobacteriaceae infection."

Scientists identify a unique combination of bacterial strains that could treat antibiotic-resistant gut infections | Broad Institute "The microbes control the growth of harmful bacteria in mice, promoting a healthier intestinal microbiome."

Commensal consortia decolonize Enterobacteriaceae via ecological control (open access)

Fig. 1: Elaboration of an 18-strain-consortium capable of decolonizing Klebsiella.