Growth yields obtained after growing C. necator JMP134 and some of its derivatives on different 2,4,6-TCP concentrations: C. necator JMP134 (X), JMP134 tcpR (▪), JMP134 tcpR (pPRTCP) (□), JMP134 tcpC (▴), JMP134 tcpC (pS7C) constitutively expressing tcpC (▵) JMP134 tcpD (•), and JMP134 tcpD (pS7D) constitutively expressing the tcpD gene (○). Values shown are means of three or four independent experiments, with standard deviations of less than 5%. An OD600 of 1.0 corresponds to about 5 × 108 CFU per ml.