The Shanghai Stock Exchange briefly suspended trading of one of Chinese property developer Shimao’s bonds on Monday, following Friday’s suspension of trading in the firm’s five other bonds due to severe declines. The trading halt came as Shimao’s unit in Shanghai defaulted on a loan after missing a payment of over $100 million last week, according to a lender’s letter obtained by Reuters on Thursday. S&P Global Ratings and Moody’s Investors Service cut the Shimao corporate family rating deeper into the junk category on Monday.  Unlike many of its Chinese peers, Shimao Group held an investment-grade credit rating, and did not breach any of the “three red lines” set by Beijing.  The group’s failure to make a loan payment heightened concerns that a liquidity crunch will spread further throughout the country’s embattled real estate industry. In the letter to investors, China Credit Trust, a company that raised trust financing on behalf of …