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If you want to shell a walnut, it helps to have a nutcracker. And if you want to digest seaweed, it helps to have the right enzymes. Now, a study in the journal Nature shows that Japanese people—but not North Americans—have what it takes to eat their sushi, and digest it, too. [Jan-Hendrik Hehemann et al, http://bit.ly/bqsLjS]
The scientists were studying a particular marine bacterium, which makes enzymes that break down the kind of seaweed used to wrap sushi. In searching the public databases, they discovered, to their surprise, that the enzymes was not just confined to ocean organisms. They also turned up in bacteria that live in the human gut.
Our intestines are teeming with trillions of bacteria from hundreds of different species. By sequencing the genomes of the microbial tenants from 30 volunteers, the scientists found that the Japanese harbor bugs with seaweed-eating enzymes. Not so the North Americans.
The enzymes were most likely gifts from a marine microbe, eaten along with some seaweed a long time ago. The marine microbe happened to transfer some of its enzyme genes to gut microbes. And with seaweed a staple in the Japanese diet, the genes stuck around. So it was a good bargain between man and microbe. Not a raw deal.
—Karen Hopkin
[The above text is an exact transcript of this podcast.]
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7 Comments
Add CommentI thought that the humat gut at birth is devoid of microbes. Pardon my naivete, but could the gut bacterium then be a product not of the historical diet, but the current diet of the Japanese? Did they test against any expatriated North Americans in Japan whose diet is now similar to the Japanese?
Reply | Report Abuse | Link to thisSeeing as the microbial diversity on cattle can be altered with a change in diet, I wonder if this is not also the case here.
Could this explain higher rates of stomach cancer in Japan?
Reply | Report Abuse | Link to thisDoes this article suggest, then, that all North American eaters of Sushi seaweed wrap are NOT digesting the seaweed? I have eaten the seaweed wrap and had no trouble digesting it. I have never been to Japan either.
Reply | Report Abuse | Link to thisof course it is not very necessary to have these enzymes from a man get birth. if a long time customed to special food, our body will act to the foods and produce corresponding enzymes day after day. evolution from generation to generation...
Reply | Report Abuse | Link to thisthe stomach cancer in japan has low rates, for their eating customs, nearly without butter and most foods made by soybean
Reply | Report Abuse | Link to thisI've never been to Japan, but I eat a lot of sushi. I eat rolls , sashimi, and my favorite is seaweed salad. I never seem to have any digestive distress upon eating these foods, which I do about twice a week. Can this microbe be acquired? I'd like to know how a North American can consume a great deal of seaweed and not experience digestive distress because my entire family eats a diet like this.
Reply | Report Abuse | Link to thisThe issue of gut bacteria begs the question of why is something not being doine to enchance the presence of good bacteria colonies that are already present in the body?
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