Tan said he didn't know whether Radtke had personally invested in bitcoin, but said First Meta's exposure to bitcoin is not significant.
Bitcoin is a digital currency that, unlike conventional money, is bought and sold on a peer-to-peer network independent of central control. Its value soared last year, and the total worth of bitcoins is now about $7 billion.
The digital currency is under scrutiny after Tokyo-based Mt. Gox, once the world's dominant bitcoin exchange, filed for bankruptcy in Japan last week, blaming hackers for the loss of 850,000 bitcoins - worth more than $550 million at today's rates. Flexcoin, a Canada-based bitcoin bank, also shut this week, saying it lost $600,000 worth of the online currency to hacker theft.
Radtke, who moved to Singapore in early 2012, previously worked at another start-up in Santa Monica, California.
(Read more: Why Mt.Gox collapse could ultimately help bitcoin)
Plug and Play's Scott Robinson, who focuses on Silicon Valley bitcoin start-ups, said Radtke's years of experience in video game virtual currencies made her an instant expert and an asset to the relatively young, predominantly male, bitcoin community.
Robinson said he had gone to bitcoin conferences with Radtke and that she had planned to visit Plug and Play's headquarters in California next month to mentor other bitcoin entrepreneurs.
"She was a go-getter, she always worked very hard ... she stuck out as one of the only women representing bitcoin."
Before heading up First Meta, Radtke had business development roles at tech start-ups Xfire and Geodelic Systems, according to information on her LinkedIn profile.