Dihydrodipicolinate synthase from Thermotoga maritima

摘要: DHDPS (dihydrodipicolinate synthase) catalyses the branch point in lysine biosynthesis bacteria and plants is feedback inhibited by lysine. from thermophilic bacterium Thermotoga maritima shows a high level of heat chemical stability. When incubated at 90 °C or 8 M urea, enzyme showed little no loss activity, unlike Escherichia coli enzyme. The active site very similar to that E. enzyme, mesophilic temperatures two enzymes have kinetic constants. Like other forms T. tetramer solution, with sedimentation coefficient 7.2 S molar mass 133 kDa. However, residues involved interface between different subunits differ those include cysteine poised form disulfide bond. Thus increased stability is, least part, explained an number inter-subunit contacts. Unlike plant not (S)-lysine, suggesting control biosynthetic pathway evolved later bacterial lineage.