Otago Researchers Target Bacterial Diseases with Phage Therapy

Researchers at the University of Otago are making strides in the development of phage therapy, a promising method to combat bacterial diseases. Led by Prof Peter Fineran and Dr Robert Fagerlund, the team is focusing on bacteriophages, which are viruses that specifically target and kill bacteria. Their research aims to address bacterial infections that threaten New Zealand’s cherry orchards, a project supported by funding from the Ministry of Business, Innovation and Employment (MBIE).

New Zealand cherry growers face significant challenges from Pseudomonas bacteria, which can cause losses of between 20% and 50% in young orchards. Traditionally, growers have relied on copper sprays to manage these infections. However, this method can harm beneficial microbes and lead to increased bacterial resistance. Prof Fineran explained that the research team is creating phage cocktails—combinations of multiple phages, each designed with unique mechanisms to penetrate bacterial defenses.

“If one phage is blocked, another still gets through,” said Prof Fineran. This approach aims to create a robust treatment that reduces the risk of bacteria developing resistance. The specificity of phages allows for targeted action against harmful bacteria while sparing beneficial ones, in stark contrast to the broad-spectrum effects of antibiotics.

Advancements in Phage Research

The team’s recent investigations have identified “jumbo phages,” which construct protective protein shells within bacteria. These shells provide a secure environment for phages to replicate, rendering them impervious to bacterial enzymes. Additionally, the researchers have examined phages that modify their DNA with sugars, offering protection against CRISPR gene-editing technologies.

Prof Fineran noted that these specialized phages, which demonstrate natural resistance to bacterial defenses, could be instrumental in future treatments. Current trials in Western hospitals are exploring the use of phages to tackle persistent infections that have proven resistant to conventional therapies. Phages are also being integrated into agricultural practices, although Prof Fineran cautioned that they should not be viewed as a comprehensive solution.

“Phages are not a silver bullet,” he stated. Instead of replacing antibiotics, phage therapy is likely to serve as a complementary approach alongside existing treatments. A deeper understanding of bacterial immune systems and the various strategies phages employ to overcome these defenses remains a crucial focus of the researchers’ ongoing work.

Ultimately, the potential of phage therapy extends beyond agricultural applications. The principles underlying this research are relevant to human and animal health, offering a pathway to innovative solutions for combating bacterial infections on multiple fronts. With continued study and application, this work could significantly impact the future of disease management in both agricultural and clinical settings.