February 2018 | Issue 34

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LKCMedicine student shifts focus from bedside to lab

​​Sean Firoz_Byline (Custom).jpgSean Firoz, Senior Executive, Communications & External Relations|

​An almost complete stranger to the lab, Gerald Ho, a former Chemistry and Physics junior college student, decided to challenge himself during the fourth year of his MBBS. Working alongside his inspirational mentor LKCMedicine Associate Professor of Human & Microbial Genetics Eric Yap, Gerald delved into the biological mysteries of bacteria's antibiotic-resistant genes for his Scholarly Project.

"I wanted to do something more hands-on and lab-based, and see if I was interested in that," said LKCMedicine Class of 2019 student Gerald. "After doing the Scholarly Project, I ended up having fun while working on it."

Gerald took a closer look at the blaOXA-23 gene in the bacteria Acinetobacter baumanii (A. baumanii). The gene in question is an antibiotic-resistant gene that resists first-line antibiotics used in hospitals, specifically carbapenems. The aim of his project? To find how many of the clinical isolates of A. baumanii carried the gene in Singapore hospitals, and whether there is a reliable way to rapidly identify the resistance status of A. baumanii using low-cost diagnostic equipment. Gerald also wanted to find out how prevalent the gene is in the environment.

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Gerald (first from the left) and his fellow colleagues​ working on bacteria in Assoc Prof Yap's lab

By collecting both clinical isolates from hospitals across Singapore and environmental ones from soil and water sources, Gerald used a real-time Polymerase Chain Reaction (PCR) machine to investigate the presence of the blaOXA-23 gene. Analysing the clinical isolates, he found that the gene was present in 57.1 per cent of multi-drug resistant (MDR) strains and in 95.6 per cent of extensively-drug resistant (XDR) ones. This is significantly higher than the prevalence in environmental isolates, which only had a 2.82 per cent prevalence, showing that people are more likely to pick up the antibiotic-resistant strain in hospitals than in the park.

"A. baumanii is commonly found in the ICU, where patients can possibly get ventilator-associated pneumonia," said Gerald.

Having established this, Gerald pushed the limits of his research, looking for a fast and cheap way to identify the gene. Assoc Prof Yap suggested that Gerald used an ultra-rapid PCR device that was built from commercially available kitchen appliances and low-cost plastics.

Gerald said, "I was trying to find the part of the gene that represents the resistance to carbapenems in the bacteria, and the ultra-rapid PCR device can perform that function at a very fast rate."

Indeed, it took Gerald just seven minutes to confirm the gene's presence. Compared with a $1,000 commercial bench-top PCR machine that takes about 20 to 30 minutes to produce a result, the homemade ultra-rapid PCR machine is portable and only costs $100, ideal for point-of-care use and use in less developed countries.

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 Gerald used a DIY PCR machine made from everyday items and home appliances (right) to study A. baumanii

​In his conclusion, Gerald reported that the blaOXA-23 gene is a reliable marker for detecting carbapenem resistance, following the prevalence of the mutated bacteria in Singapore hospitals. Based on this, clinicians may want to consider using alternative first-line antibiotics such as tetracyclines and polymyxin instead of carbapenems.

Overall, it took Gerald the entire six weeks of the module to finish his Scholarly Project, and he relished every second in the laboratory.​

"Besides getting to use the machines and find out what types of bacteria there are, I've also learnt that a good team makes integration seamless and laboratory work fun," said Gerald.

At the end of the six weeks, LKCMedicine held a Scholarly Projects Celebration on 10 January, where Gerald received the top prize for the Laboratory & Translational Research Category.

Pleasantly surprised, Gerald said, "This showed me how much I can achieve if I put my mind to it even without having prior knowledge, and how far I can push myself while having fun at the same time."