You might say that Australian microbiologist Barry Marshall and the tiny Helicobacter pylori bacteria go a long way back.
In 1984, he famously chugged a Petri dish teeming with live bacteria in the name of science. It gave him nausea and bad breath that lasted several days but proved his point - that the H. pylori was the root cause of most peptic ulcers and not stress or spicy foods, as was commonly believed at the time.
His study eventually won him and his partner, Dr Robin Warren, the Nobel Prize in 2005. Professor Marshall's fascination with Helicobacter has far from waned since.
Newly appointed as a visiting professor at the Nanyang Technological University (NTU), he now wants to learn how H. pylori reacts to traditional Chinese medicine, prevents allergies, and even serves as a marker of human ancestry.
And Singapore, with its diverse population, is fertile ground for further research on the gut-dwelling bacterium that affects nearly half of the world's population.
"You don't need to have thousands of patients to make a discovery - you just need to have a careful look at a small number of patients," said the 65-year-old in an interview with The Straits Times.
"Really, we're all very similar, so something that happens here can be extrapolated elsewhere."
His two-year term at NTU will see him involved in events at the Lee Kong Chian School of Medicine, as well as other institutes such as School of Biological Sciences and the Singapore Centre for Environmental Life Sciences Engineering.
"I know there's good chemistry here. Anything related to metabolism of bacteria is interesting to me, and I know there's expertise here."
The son of a tradesman on the mines, the young Barry grew up in Western Australia interested in all things science. It was perhaps because of his mother's nursing background, however, that he eventually gravitated towards gastroenterology, the study of the digestive system.
His famous self-experiment, which gave him gastritis, paved the way for infected patients with ulcers to be prescribed antibiotics, rather than antacids.
It also shed light on stomach cancer - one of the most common cancers both in Singapore and the wider world - which was found to be linked to H. pylori infections. An estimated three in 10 people here are infected with the bacterium, which is developing a resistance to standard Western antibiotics.
But always one to think out of the box, Prof Marshall believes he might have found a solution in TCM. Evidence from China suggests some TCM may kill off this bacterium, he said, although without hard scientific evidence, it is difficult to know what is happening.
"I believe that there is some TCM that inhibits Helicobacter, but because it's not studied carefully you can't really tell," he explained. "I saw a patient ... and he promised me he never took antibiotics but his Helicobacter went away - and he was taking TCM every day."
Prof Marshall is also interested in the genomics of the bacteria, which humans have been passing down to their children for thousands of years. Mutations that occur each time this happens mean the bacteria can be used as a marker of human history.
"It's quite an accurate way of looking at somebody's ancestry," Prof Marshall said. "For every person, by the end of your life, you've got a slightly different strain."
H. pylori has coexisted with humans for so long because it tends to stop the immune system from overreacting - that is, having allergic reactions. He hopes to harness this by using dead H. pylori in food products, which could help lower the risk of children developing allergies while not putting them at risk of harmful infections later in life.
When conditions like asthma or eczema flare up, Prof Marshall explained, it is always a challenge to find medication that controls the condition without being too strong.
He said: "If you had something that was almost like a natural therapy that decreased the chances of asthma in later life - even if it was only a 30 per cent benefit - it would probably be worth it."
