Preparation of soluble isotopically labeled NKp30, a human natural cytotoxicity receptor, for structural studies using NMR

► Optimized gene for expression of soluble human NKp30 in Escherichia coli. ► High-level expression occurred in M9 medium with low glucose. ► Simplified 4 day protocol yielded 10 mg of well folded protein per 1 L medium. ► Pure homogenous protein also obtained in isotopically labeled forms. ► Highly soluble monomeric protein stabilized with a cysteine bridge.