Without This Gut Bacteria, Digestion of Sushi and Seaweed is Impossible: New Study

Gut bacteria inside the human body are capable of digesting food nutrients, notably from sushi and seaweed.

However, this is not always the case for our gut microbes as a new study discovered that the bacteria in the human gut microbiome was once not capable of digesting all sea-based food.

Lateral Gene Transfer

Researchers discovered the gut bacteria in humans capable of digesting sushi and seaweed were once found only from ocean bacteria, as per a new study published in Cell Host & Microbe on Wednesday, March 2.

The study explored the journey of seaweed-digesting marine bacteria to the human gut.

Researchers from the University of Michigan in Ann Arbor, Michigan, have identified several historical events that allowed the marine bacteria called Bacteroidetes, once found only in the sea, to be genetically transferred into the human gut microbiome in a process called lateral gene transfer.

Following the lateral gene transfer, the study revealed that human gut bacteria were able to acquire a genetic transformation from Bacteroidetes through unspecified separate occurrences in history that allowed our gut bacteria to digest complex carbohydrates found in sushi and seaweed.

Genes for Complex Carbohydrate

The ocean bacteria Bacteroidetes are said to possess genes that allow to process of complex carbohydrates.

It is through the lateral gene transfer that allowed the genes are integrated into the microbes living in the human gastrointestinal tract.

In the new study, it was confirmed the human gut was once unable to digest all kinds of ocean-based food. It was only until the said process that allowed our gut bacteria to digest ocean food like sushi and seaweed that contain complex carbohydrates, as per Phys.org.

Bacteroidetes reportedly possess a gene that can break down and digest the complex carbohydrate called porphyran, which is found in some sea-based food like sushi and seaweed.

The gut bacteria of humans eventually incorporated these genes from the ocean bacteria.

In the gastrointestinal tract, the so-called bacteria Firmicutes, which are prevalent in the human gut, were able to acquire the sushi and seaweed-digesting genes from the ocean bacteria, as per Phys.org.

However, humans most likely acquired the bacteria when eating marine food that started in ancient times.

Without the Bacteroidetes and Firmicutes microbes, it would be impossible for humans to digest sushi and seaweed, which are popular delicacies in East Asia, especially in Japan.

With this, the study highlights the dynamic interconnection between marine food consumption and humans.

Human Gut Microbiome

According to the United States National Institutes of Health (NIH), trillions of microorganisms live inside the human body, including in the human gut microbiome or the gastrointestinal tract.

Microorganisms in the form of bacteria in the gut acts as catalysts for breaking down the nutrients from the food we eat.

The NIH stated that human gut bacteria are not only capable of processes related to food breakdown of carbohydrates, lipids, and proteins so the human body can absorb them, but the microbes are also responsible for influencing the overall health.

Moreover, previous research about the human gut bacteria has shown these microorganisms have a profound impact on human emotions, even on cognitive functions, such as the formation and retainment of memories, as per Alzheimer's Research UK.