The shipworm, a bivalve mollusc, can cause destruction to wooden ship hulls, wharves, and other submerged wooden structures.
“The ancient Greeks wrote about them, Christopher Columbus lost his fleet due to what he called ‘the havoc which the worm had wrought,’ and, today, shipworms cause billions of dollars of damage a year,” said Reuben Shipway, adjunct assistant professor in microbiology at UMass Amherst and research fellow at the Centre for Enzyme Innovation at the University of Portsmouth, UK.
Reuben Shipway is part of a research team investigating this incredible creature – and its important role in mangrove forest ecosystems and responsible for cycling a huge amount of carbon worldwide.
“We still don’t know how they do what they do,” commented Reuben Shipway.
Part of the problem is that the nutritious part of wood – cellulose – is encased in a thick and extremely difficult-to-digest layer of lignin. “Imagine a really thick, unbreakable eggshell,” says senior author and UMass professor of microbiology, Barry Goodell.
Certain fungi possess enzymes capable of digesting the lignin, and it has long been thought that symbiotic bacteria living in shipworms’ gills also had the enzymes.
“We thought that the bacteria were doing the work,” says Goodell, “but we now know they are not.”
Researchers are still trying to figure out what within the shipworm could be responsible for breaking down the lignin.
“I combed through the entire genomes of five different species of shipworm,” says Stefanos Stravoravdis, a graduate student in microbiology at UMass, “looking for specific protein groups which create the enzymes that we know are capable of digesting lignin. My search turned up nothing.”
This, however, is not the end of the story, and the team will be publishing more research in the near future that will help unravel the mystery of how shipworms eat wood.
“We need to understand this process” says Stravoravdis.
This new research from the University of Massachusetts Amherst is published in Frontiers in Microbiology and reveals that we still don’t know the most basic thing about them: how they eat.