R. Gutknecht et al., The dihydroxyacetone kinase of Escherichia coli utilizes a phosphoprotein instead of ATP as phosphoryl donor, EMBO J, 20(10), 2001, pp. 2480-2486
The dihydroxyacetone kinase (DhaK) of Escherichia coli consists of three so
luble protein subunits, DhaK (YcgT; 39.5 kDa) and DhaL (YcgS; 22.6 kDa) are
similar to the N- and C-terminal halves of the ATP-dependent DhaK ubiquito
us in bacteria, animals and plants. The homodimeric DhaM (YcgC; 51.6 kDa) c
onsists of three domains. The N-terminal dimerization domain has the same f
old as the IIA domain (PDB code 1PDO) of the mannose transporter of the bac
terial phosphoenolpyruvate:sugar phosphotransferase system (PTS), The middl
e domain is similar to HPr and the C-terminus is similar to the N-terminal
domain of enzyme I (EI) of the PTS, DhaM is phosphorylated three times by p
hosphoenolpyruvate in an EI- and HPr-dependent reaction. DhaK and DhaL are
not phosphorylated, The IIA domain of DhaM, instead of ATP, is the phosphor
yl donor to dihydroxyacetone (Dha), Unlike the carbohydrate-specific transp
orters of the PTS, DhaK, DhaL and DhaM have no transport activity.