Australasian Science: Australia's authority on science since 1938

A New Silver Species of Staphylococcus

A Northern Territory-based research project has uncovered two new species of staphylococcus. One of the two has been officially registered as Staphylococcus argenteus, or more commonly “silver staph”.

A/Prof Steven Tong of the Menzies School of Health Research says that both species, S. argenteus and S. schweitzeri, may not be distinguished in the laboratory from golden staph (S. aureus) using standard laboratory techniques.

“The discovery is important because it deepens our understanding of the whole group of Staphylococci, which are a major cause of human disease,” Tong said.

The research group has spent the past 10 years looking into the genetic sequences of golden staph recovered from Northern Territory communities. Some strains looked different with regards to their DNA sequence, leading to further investigations.

“We came across some unusual results while investigating the genetic sequences of golden staph from the NT and across the world,” Tong said. “Further investigations showed us we were dealing with three entirely separate species. These weren’t just different makes of cars, but different types of vehicles.

“More recent studies have shown that silver staph causes less severe disease. However, the silver staph has demonstrated an ability to become resistant to penicillin-like antibiotics, just like golden staph, which has become methicillin-resistant Staphylococcus aureus (MRSA). In fact, these different species can swap genes with each other – a bit like bacteria having sex.

“It is likely that infections due to the different species can be treated differently,” Tong said. “Additionally, the scientific community can now look at what sets S. aureus apart from the other two species and understand why it is better able to cause disease.”