Purdue Biomakers




Basic Parts

Exopolyphosphatase (PPX) hydrolyzes of the terminal phosphate of a polyphosphate chain [1] The presence of PPX decreases polyphosphate accumulation, which allows PPX to maintain polyphosphate balance. [3] There are two variants of PPX proteins, PPX1 and PPX2, and we have selected one PPX2 homolog from M. phosphovorus to express in E. coli.

BBa_K1988000 : PPX2 homologue: exopolyphosphatase from M. phosphovorus

Inorganic phosphate transporters (Pit) transport metal-chelated phosphate across the cell membrane using the proton motive force. [1] We have selected three Pit gene homologs from M. phosphovorus for expression in E. coli.

BBa_K1988002 : Pit A: Inorganic P transporter from M. phosphovorus
BBa_K1988004 : Pit B: Inorganic P transporter from M. phosphovorus
BBa_K1988006 : Pit C: Inorganic P transporter from M. phosphovorus

Polyphosphate-dependent glucokinases (PPGK) catalyze the first step of glycolysis, the phosphorylation of glucose using a phosphate group from polyphosphate or ATP. We have selected two PPGK homologs from M. phosphovorus to express in E. coli, one of which is the only protein of the ten chosen that have been characterized. The characterized PPGK cannot use ATP, and is referred to as PPGK ATP-independent (ATPI). [1]

BBa_K1988008 :Polyphosphate ATP Dependent Glucokinase (PPGK)
BBa_K1988010 : Polyphosphate ATP Independent Glucokinase (PPGK ATPi)
Polyphosphate kinases (PPK) catalyze the reversible transfer of phosphate between nucleoside phosphates and polyphosphates. [1] There are three PPK subtypes: PPK1 favors polyphosphate synthesis, PAP favors polyphosphate hydrolysis, and PPK2’s affinity for hydrolysis or synthesis varies by homolog. [2] We have selected four PPK homologs from M. phosphovorus to express in E. coli: one PPK1, two PPK2s, and one similar to both a PPK2 and PAP.

BBa_K1988012 : Polyphosphate kinase from M. Phosphovorus (PPK1)
BBa_K1988014 : Polyphosphate kinase 2 Homolog A from M. phosphovorus (PPK2a)
BBa_K1988016 : Polyphosphate kinase 2 Homolog B from M. phosphovorus (PPK2b)
BBa_K1988018 : Polyphosphate kinase 2 Homolog C from M. phosphovorus (PPK2c)

Composite Parts

We added a medium-strength promoter (Anderson promoter J23160), RBS (J34803), and a his-tag (K844000) to all parts to make our composite part collection, listed below.