The regulation of the ntdABC operon. The operon is activated by ntdR (NTD biosynthesis operon regulator) and neotrehalosadiamine. The operon is inhibited by glcP (Glucose/mannose transporter). NtdR is required for the proper function of crp in transcription of the operon and ntdR cannot bind to the promoter without neotrehalosadiamine. GlcP controls the amount of glucose that is present inside the cell (acts as a glucose sensor), therefore, it indirectly inhibits ntdR function. There are three products from this operon: ntdA (3-oxo-glucose-6-phosphate:glutamate aminotransferase), ntdB (Kanosamine-6-phosphate phosphatase) and ntdC (Glucose-6-phosphate 3-dehydrogenase). These products are all enzymes used in the biosynthesis of neotrehalosadiamine from glucose. NtdC is used to turn D-glucose-6-phosphate (imported into the cell by ptsG: PTS system glucose-specific EIICBA component) to 3-dehydro-D-glucose-6-phosphate. NtdA is used to turn 3-dehydro-D-glucose-6-phosphate to D-kanosamine-6-phosphate. NtdB is used to turn D-kanosamine-6-phosphate to kanosamine. The process of kanosamine to neotrehalosadiamine is unknown.

Neotrehalosadiamine biosynthesis: ntdA, ntdB, ntdC References