Two of Asia’s most active investment funds are to spend close to $1bn to acquire a landmark stake in a leading US producer of natural gas.Temasek, the Singapore state investment fund, and Hopu Investment Management, a Beijing-based firm, have agreed to buy $600m of convertible preferred stock in New York-listed Chesapeake Energy.The funds have an additional 30-day option to acquire a further $500m of the stock, which they are “highly likely” to exercise alongside other investors, according to people familiar with the matter.The Asian funds believe that the price for natural gas, currently trading at about a third of the price of oil on an equivalent basis, is at a low point and that demand for the commodity will climb because of environmental reasons.The investment was disclosed by Chesapeake after the US market close on Monday as part of steps by the gas producer to raise up to $5bn over the next two years to reduce debt and attain an investment-grade rating.The convertible preferred stock carries a coupon of 5.75 per cent. The prospective $1.1bn investment would eventually translate into an equity holding in Chesapeake of about 7 per cent.Temasek acquired $500m in convertible preferred stock, with Hopu the remainder, said people familiar with the matter.Seatown, a new affiliate of Temasek, is likely to invest in a portion of the second tranche, alongside other Asian investors.Hopu was set up in 2008 by ex-Goldman Sachs dealmakers and has made a series of high-profile investments – often alongside Temasek – in Chinese banks and food producers.