Researchers Target Bacterial Diseases with Innovative Phage Therapy

Researchers at the University of Otago are pioneering efforts to develop phage therapy as a solution to combat bacterial diseases affecting agriculture and potentially human health. Led by Prof Peter Fineran and Dr Robert Fagerlund, the team is investigating bacteriophages—viruses that specifically target and kill bacteria. Their work is particularly focused on addressing the challenges posed by bacterial diseases in cherry orchards across New Zealand.

The project has received vital funding from the Ministry of Business, Innovation and Employment (MBIE), allowing the researchers to explore innovative treatments that could significantly reduce crop losses. In New Zealand’s cherry orchards, Pseudomonas bacteria are responsible for devastating losses, estimated between 20% and 50% in young trees. Traditionally, growers have relied on copper sprays, a method that is increasingly ineffective as bacteria develop resistance and also harms beneficial microbes.

Developing Phage Cocktails for Precision Treatment

To counteract these issues, the research team is developing phage cocktails—blends of multiple phages that use different mechanisms to infiltrate bacterial defenses. “If one phage is blocked, another still gets through,” Prof Fineran explained. This approach creates a robust treatment capable of minimizing the emergence of resistance, which is a significant concern with conventional antibiotics.

The specificity of phages means that their application can selectively target harmful bacteria while preserving beneficial species, avoiding the “carpet-bombing” effect commonly associated with antibiotics. The principles of this research extend beyond agriculture; they are applicable to human and animal pathogens as well.

Research Innovations and Future Applications

Recent findings from the team include the discovery of “jumbo phages,” which construct protein shells within bacteria, providing a protected environment where phages can replicate without interference from bacterial enzymes. Additionally, they have studied phages that modify their DNA with sugars, which shields them from CRISPR-based gene editing techniques. “Some added one sugar, others added up to three, each offering protection against different bacterial defenses,” Prof Fineran noted, indicating that these phages could enhance treatment efficacy.

Phages are already being tested in hospitals, particularly in challenging cases where traditional treatments have failed. They are also gaining traction in mainstream agricultural practices. Nevertheless, Prof Fineran cautioned that phages should not be seen as a “silver bullet.” Instead, they are expected to complement existing treatments rather than replace them.

“To achieve the desired outcomes, it is essential to select the right phages, which requires a deep understanding of bacterial immune systems and the various strategies phages use to overcome these defenses. This understanding underpins our core fundamental research,” Prof Fineran concluded. As the team continues its pioneering work, the potential for phage therapy to revolutionize the fight against bacterial infections remains promising, both in agriculture and human health.