Returning Home-R&D of Animal Antibiotics Updated in July 2018

Collaboration with Merck Upon Return to Japan

In January 1973, right after Omura returned home from Wesleyan University, he started to prepare for the joint research with Merck. At that time, Japan was still a poor country and the university laboratory was suffering from lack of research funds and Omura was very concerned.

By going into such a collaborative agreement, Omura thought of continuing his research through funds provided by Merck. The research theme was to find useful substances from chemicals which microorganisms produce. The discovered chemicals are sent to Merck, and Merck would formulate medicine from it

Omura’s laboratory decided to collect soil samples from every corner of Japan. Omura always carried a small plastic bag and a spoon to scoop up some soil whenever he had time. He would take that soil back to the laboratory. One gram of soil, carry more than 100 million microorganisms. The team would culture each microorganism, classify it, and examine what kind of substance it is producing.

Omura’s lab members would go through many references from around the world, and whenever they found microbes or chemicals that were still unknown, they would send them to Merck by airmail. Merck would investigate whether it could be used to produce medicine. Merck and Omura’s laboratory started the collaboration successfully.

A Unique Agreement: The First of Its Kind

Omura’s wife Fumiko, who accompanied him to the U.S. had learnt English at a night-class of a local elementary school and in six months, she mastered daily conversation. Her bright personality also helped her communicative skills. She did not hesitate in whatever she wanted to do and her straightforward personality was welcomed by American people. She had become a popular figure on campus. Research staff and administrative personnel at Professor Tishler’s lab socialized like a big family. Satoshi and Fumiko often invited them to their house and hosted parties. Fumiko's caring hospitality was always appreciated by everyone.

One time, Fumiko was doing something intently in one of the chemistry classrooms long after activity hours had ended. When Omura peeked in, Fumiko was teaching how to use a Japanese abacus or soroban to Wesleyan students and staff. She distributed the soroban to all the participants. They had been specially ordered from Japan. This sight amused Omura very much. One time, Fumiko competed with a computer on her soroban. For the four arithmetic operations (adding, subtracting, multiplying and dividing), Fumiko had beaten the machine. She had proudly recounted this incident to Omura when he reached home. Omura always enjoyed hearing Fumiko’s stories.

Conquering the World with Antibiotics for Animals

In order to efficiently discover microbial substances, Omura’s laboratory formed several teams. When someone brought a spoonful of soil sample to the laboratory, one team would culture the microorganism in the soil. Another team would take out the microorganism. Yet another team would investigate the usefulness of the substance. The whole research proceeded efficiently.

Conducting research in such teamwork seemed to suit Japanese laboratory members. Omura demonstrated great leadership in putting these different teams together.

Merck immediately worked on animal experiments for useful substances sent in by Omura’s Laboratory. In the beginning, they performed various experiments with rats and mice, and effective substances were extensively used for experiments on cattle and pigs.

At Merck, William Campbell was the leader of the project, in charge of checking and screening which microbial substances were effective in animal experiments. In one case, cow’s skin was bitten by mites. When the mites spread through the cow’s body, the cow lost weight and weakened. Livestock breeders were suffering from these symptoms among their cattle when the mites spread widely in the ranch.

However, animal antibiotics made from substances sent in from Omura’s laboratory proved to work well on these mites, and it was possible to get rid of them within a short period of time.

This antibiotic would later be used all over the world. Merck also produced many other animal antibiotics sold everywhere around the world today. For more than 20 years, Merck had been the top runner in the sales of animal antibiotics. With cooperation from Merck, microorganisms discovered by Omura and his team led to the development of such antibiotics which were reputed worldwide.


Omura collecting soil sample with a spoon Photo courtesy of Kitasato Institute
Omura collecting soil sample with a spoon Photo courtesy of Kitasato Institute
Cultivating microorganisms in soil and classifying target microorganisms
Cultivating microorganisms in soil and classifying target microorganisms Photo courtesy of Kitasato Institute
After a few mites bite the cattle
After a few mites bite the cattle, they can spread through the whole body and can weaken the animal
Mites were successfully removed with antibiotics jointly developed by Omura’s laboratory and Merck
Mites were successfully removed with antibiotics jointly developed by Omura’s laboratory and Merck Photo courtesy of Kitasato Institute