In a remote Greenland fjord, a few miles from the Kangilinnguit Naval Base and just beneath the frigid water’s surface, lurks the secret to a better laundry detergent. At least that’s what Jan Kjølhede Vester, a graduate student at the University of Copenhagen, is banking on. Over the last few years, he’s been studying the bizarre columns of rock that rise like fingers reaching out from the seafloor, examining native microbes for signs of unusual – and potentially useful – metabolic activities.
The columns are made of ikaite, an unusual mineral that precipitates when ion-rich spring water from Greenland mixes with seawater. This type of reaction happens in oceans around the world, forming ordered, traditional calcium carbonate, but phosphate molecules in this spring water prevent formation of the orthodox stoichiometry. Instead, the carbonate forms around water molecules, and a metastable mineral found nearly nowhere else in the world is created.
Vester is looking for extremozymes: enzymes that perform their biochemical magic in extreme physical and chemical conditions. And the ikaite rock columns of the Ikka Fjord are most certainly extreme environments, with an alkaline pH and water temperatures hovering around 6 C. Mining extremophiles’ enzymes for useful molecular machines is a little like playing the lottery: your chances of striking it rich aren’t great, but the payoff could be immense. Taq polymerase – the enzyme that allows for genetic amplification and the sort of molecular magic that enables the entire CSI franchise – was first discovered in a Yellowstone hot spring. Taq has been the field’s most widely used product, but other extremozymes have proven useful when brought to bear on a range of industrial processes.
With this in mind, scuba divers collected rock samples in the Ikka fjord that proved to be veritable zoos, with lawns of cyanobacteria and algae coating the surface and unknown microbes feasting on organic matter in the alkaline column interiors. As Vester describes it, “the divers would go into the water and we would have radio contact with them while they performed the actions we requested – sawing off columns, collecting sediment samples, sea water, or drilling holes and inserting a hose, enabling us to collect the alkaline water from inside the columns.”
In order to probe the organisms for new, useful functions, Vester performed a little genetic cutting and pasting. He extracted the genetic material, chopped it up with enzymes, and put each fragment into a ring of DNA. These rings were inserted it into E. coli, which served as the molecular fabrication facility and produced the enzymes encoded in each fragment at high levels.
Each modified E. coli was put through a battery of tests to see how its enzymatic arsenal performed. Vester tested enzymes like phosphatases (useful in molecular biology), β-galactosidases (produce lactose-free dairy products), proteases (break down proteins in stains), and amylases (decompose starches). Ultimately, he will incorporate assays for biofuel-relevant molecules like cellulases.
Enzymes adapted to cold, alkaline conditions like those found in ikaite offer particular advantages. “In general,” Vester notes, “cold active enzymes have higher maximum reaction rates than their mesophilic counterparts.” Specific industries could benefit as well. Detergent creates alkaline conditions, so high-pH proteases or amylases could be worth millions. Keeping temperatures low during lactose-free milk production would preserve flavor compounds and discourages spoilage.
Soon, perhaps, when your favorite shirt emerges from the washing machine unscathed after a dinner party mishap, you’ll have the ikaite columns of Greenland to thank.
