What’s for Dinner?

3-course Contemporary Dinner Incorporating Coca Cola

The Menu

Grilled Scallop with Molecular Coca Cola Caviar Served with Mango Salad

Braised Veal Cheek with Coca Cola Barbecue Sauce Served with Mashed Potato and Assorted Vegetables

Dessert – Bread Pudding and Coca Cola Sherbet

Decorative Sushi

Kazari Maki Sushi

Japanese Guts Are Made for Sushi

Eat up. Microbes that dwell in the guts of Japanese people but not in North Americans have some of the same seaweed-digesting enzymes as the marine bacterium Zobellia galactanivorans (inset).

Americans don’t have the guts for sushi. At least that’s the implication of a new study, which finds that Japanese people harbor enzymes in their intestinal bacteria that help them digest seaweed–enzymes that North Americans lack. What’s more, Japanese may have first acquired these enzymes by eating bacteria that thrive on seaweed in the open ocean.

Mirjam Czjzek didn’t set out to compare cross-cultural eating habits. Instead, the chemist at the Station Biologique de Roscoff, on the coast of Brittany in France, was interested in what it takes to digest a piece of seaweed. Unlike in land plants, the carbohydrates that make up seaweed are spangled with molecules of sulfur, so special enzymes are needed to break them down.

To figure out exactly which enzymes are necessary, Czjzek and colleagues embarked on what she calls “treasure-hunting in the marine bacterial genome.” The researchers focused on Zobellia galactanivorans, a marine bacterium known to munch on seaweed. The hunt turned up five genes in Z. galactanivorans that seemed to code for enzymes that could break down the particular carbohydrates found in the marine algae. When the researchers transferred these genes to another bacterium forced to eat seaweed carbohydrates, they found that two genes were particularly active.

Czjzek wondered where else these genes might be lurking. So she used a computational method known as BLAST to scan vast banks of metagenomic data—the genomes of bacteria gathered from the environment—for sequences that matched up with the two Z. galactanivorans genes. That’s when the surprise came.

“They were all, except one, from marine bacteria,” Czjzek says. “The one exception … came from human gut samples.” The bacterium in question is known as Bacteroides plebeius, and it has been found only in Japanese people. Wondering whether the enzymes were unique to Japanese individuals, Czjzek’s team compared the microbial genomes of 13 Japanese people with those of 18 North Americans. Five of the Japanese subjects harbored the enzyme, but among the North Americans, “we didn’t find a single one,” says Czjzek, whose team reports its findings tomorrow in Nature.

Where would bacteria inside the human gut get ahold of a seaweed-digesting enzyme? Czjzek speculates that they could have grabbed it from bacteria that live on the seaweed. She notes, for example, that according to tax records dating back to the 8th century C.E., seaweed was used as a form of payment in Japanese society. “That shows the importance of this type of good,” Czjzek says. With nori, the seaweed used to wrap sushi or wakame, a green seaweed often served in miso soup, being consumed day after day, the bacteria in the gut would have a chance to incorporate genetic material from their marine-dwelling cousins. “Traditionally, [the Japanese] eat [seaweed] raw, not sterile,” says Czjzek. “This makes the contact possible.”

The ability to munch on a few extra carbohydrates might have given these gut bacteria a leg up over their thousands of competitors, says Czjzek. It also may help their human hosts. Because gut bacteria can squeeze energy from carbohydrates that human enzymes can’t break down, these adapted microbes might help Japanese who dine on seaweed get more nutrition from their meal than do North Americans, she says.

Scientists have thought that gut bacteria might pick up genes from other microbes, a process known as lateral gene transfer, “but there hasn’t been an example this clear before,” says Ruth Ley, a microbiologist at Cornell University. “I think it’s the first demonstration of how people’s culture has impacted the [bacteria in the] gut.”

Source: American Association for the Advancement of Science

Easy Weekend Vegetarian Grill

Ingredients

6 green onion, thinly sliced
2 cloves garlic, minced
2 tbsp olive oil
2 tbsp balsamic vinegar
1/2 cup chopped fresh basil leaves
1 large eggplant
2 large firm but ripe tomatoes
1/4 cup Italian salad dressing
8 oz spreadable spinach-feta cream cheese

Method

  1. Lightly oil grill, then preheat barbecue to medium-high.
  2. Mix oil with vinegar, green onion, garlic and basil. Set aside.
  3. Slice eggplant into 8 rounds, at least 1/2 -inch thick. Core tomatoes, then slice each horizontally into 4 thick rounds.
  4. Lightly brush both sides of eggplant and tomato rounds with dressing. Place on barbecue. Grill with lid closed until eggplant is just tender, from 3 to 4 minutes per side. Grill tomatoes until grill marks form, from 1 to 2 minutes per side. Remove and place on platter.
  5. Divide cream cheese evenly over eggplant, spooning about 1 tbsp over each hot slice. Press cheese down to flatten slightly. Cover with a slice of tomato, pressing into the cream cheese to help it stick. Transfer stacks to serving plates. Top each stack with about 2 tbsp green onion mixture and serve.

Source: Chatelaine


Today’s Comic