Bacterial slime helps cause serious disease

May 5, 2008

Leptospirosis is a serious but neglected emerging disease that infects humans through contaminated water. Now research published in the May issue of the journal Microbiology shows for the first time how bacteria that cause the disease survive in the environment.

Leptospirosis is a major public health problem in South East Asia and South America, with over 500,000 severe cases every year. Between 5% and 20% of these cases are fatal. Rats and other mammals carry the disease-causing pathogen Leptospira interrogans in their kidneys. When they urinate, they contaminate surface water with the bacteria, which can survive in the environment for long periods.

“This led us to see if the bacteria build a protective casing around themselves for protection,” said Professor Mathieu Picardeau from the Institut Pasteur in Paris, France. Previously, scientists believed the bacteria were ‘planktonic’, living freely in the water. But Professor Picardeau and his team have shown that L. interrogans can make biofilms, which could be one of the main factors controlling survival and disease transmission.

Many different bacteria make biofilms, which protect them against harsh conditions and make them more resistant to antibiotics. They do this by producing a slime, in which the colony can grow unharmed. “90% of the species of Leptospira we tested could form biofilms. It takes L. interrogans an average of 20 days to make a biofilm,” said Professor Picardeau.

This ability may contribute to the long-term survival of the bacteria in environmental water and even help them cause disease in humans. Biofilm formation might also play an important role in keeping the bacteria alive in the kidneys of animals such as rats without causing disease.

“This finding is a step forward in our understanding of Leptospirosis. We now need to study the mechanism of biofilm formation in both fresh water and renal tubules in animal kidneys,” said Professor Picardeau. “We hope our research will lead to the identification of new strategies to diagnose and prevent this neglected emerging disease.”

Source: Society for General Microbiology

Explore further: What is life?

Related Stories

What is life?

October 20, 2015

"Why would NASA want to study a lake in Canada?"

Human-like nose can sniff out contamination in drinking water

September 9, 2015

A bioelectronic nose that mimics the human nose can detect traces of bacteria in water by smelling it, without the need for complex equipment and testing. According to a study published in Biosensors and Bioelectronics the ...

Team identifies the off switch for biofilm formation

August 24, 2015

Bacteria are best known as free-living single cells, but in reality their lives are much more complex. To survive in harsh environments, many species of bacteria will band together and form a biofilm—a collection of cells ...

Recommended for you

A common mechanism for human and bird sound production

November 27, 2015

When birds and humans sing it sounds completely different, but now new research reported in the journal Nature Communications shows that the very same physical mechanisms are at play when a bird sings and a human speaks.

Moonlighting molecules: Finding new uses for old enzymes

November 27, 2015

A collaboration between the University of Cambridge and MedImmune, the global biologics research and development arm of AstraZeneca, has led researchers to identify a potentially significant new application for a well-known ...

Four pre-Inca tombs found in Peru's Lima

November 27, 2015

Archaeologists in Peru have found four tombs that are more than 1,000 years old in a pyramid-shaped cemetery that now sits in the middle of a residential neighborhood in Lima, experts said.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.