Limits...
C(1) compounds as auxiliary substrate for engineered Pseudomonas putida S12.

Koopman FW, de Winde JH, Ruijssenaars HJ - Appl. Microbiol. Biotechnol. (2009)

Bottom Line: This approach resulted in a remarkably increased biomass yield on the primary substrate glucose when cultured in C-limited chemostats fed with a mixture of glucose and formaldehyde.With increasing relative formaldehyde feed concentrations, the biomass yield increased from 35% (C-mol biomass/C-mol glucose) without formaldehyde to 91% at 60% relative formaldehyde concentration.The RuMP-pathway expressing strain was also capable of growing to higher relative formaldehyde concentrations than the control strain.

View Article: PubMed Central - PubMed

Affiliation: B-Basic, Delft, The Netherlands. F.W.Koopman@tudelft.nl

ABSTRACT
The solvent-tolerant bacterium Pseudomonas putida S12 was engineered to efficiently utilize the C(1) compounds methanol and formaldehyde as auxiliary substrate. The hps and phi genes of Bacillus brevis, encoding two key steps of the ribulose monophosphate (RuMP) pathway, were introduced to construct a pathway for the metabolism of the toxic methanol oxidation intermediate formaldehyde. This approach resulted in a remarkably increased biomass yield on the primary substrate glucose when cultured in C-limited chemostats fed with a mixture of glucose and formaldehyde. With increasing relative formaldehyde feed concentrations, the biomass yield increased from 35% (C-mol biomass/C-mol glucose) without formaldehyde to 91% at 60% relative formaldehyde concentration. The RuMP-pathway expressing strain was also capable of growing to higher relative formaldehyde concentrations than the control strain. The presence of an endogenous methanol oxidizing enzyme activity in P. putida S12 allowed the replacement of formaldehyde with the less toxic methanol, resulting in an 84% (C-mol/C-mol) biomass yield. Thus, by introducing two enzymes of the RuMP pathway, co-utilization of the cheap and renewable substrate methanol was achieved, making an important contribution to the efficient use of P. putida S12 as a bioconversion platform host.

Show MeSH

Related in: MedlinePlus

C-limited chemostat cultures of P. putida S12pJNNhp(t) (triangles) and P. putida S12pJNN(t) (squares) at D = 0.03 h−1, grown on mineral salts medium with 30 mM of total carbon (60% of all carbon originates from methanol). The data presented are from a single representative experiment
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2690845&req=5

Fig4: C-limited chemostat cultures of P. putida S12pJNNhp(t) (triangles) and P. putida S12pJNN(t) (squares) at D = 0.03 h−1, grown on mineral salts medium with 30 mM of total carbon (60% of all carbon originates from methanol). The data presented are from a single representative experiment

Mentions: P. putida S12pJNNhp(t) reached steady state under these conditions, in contrast to the empty vector control strain (Fig. 4). Approximately 25% of the methanol feed was not metabolized, but no formaldehyde or formate accumulation was observed. The co-utilization of methanol resulted in a significant improvement of the biomass yield to 84% biomass-per-glucose (C-mol). After stopping the glucose feed, the culture washed out as observed in the glucose/formaldehyde experiments while culture methanol levels increased.Fig. 4


C(1) compounds as auxiliary substrate for engineered Pseudomonas putida S12.

Koopman FW, de Winde JH, Ruijssenaars HJ - Appl. Microbiol. Biotechnol. (2009)

C-limited chemostat cultures of P. putida S12pJNNhp(t) (triangles) and P. putida S12pJNN(t) (squares) at D = 0.03 h−1, grown on mineral salts medium with 30 mM of total carbon (60% of all carbon originates from methanol). The data presented are from a single representative experiment
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2690845&req=5

Fig4: C-limited chemostat cultures of P. putida S12pJNNhp(t) (triangles) and P. putida S12pJNN(t) (squares) at D = 0.03 h−1, grown on mineral salts medium with 30 mM of total carbon (60% of all carbon originates from methanol). The data presented are from a single representative experiment
Mentions: P. putida S12pJNNhp(t) reached steady state under these conditions, in contrast to the empty vector control strain (Fig. 4). Approximately 25% of the methanol feed was not metabolized, but no formaldehyde or formate accumulation was observed. The co-utilization of methanol resulted in a significant improvement of the biomass yield to 84% biomass-per-glucose (C-mol). After stopping the glucose feed, the culture washed out as observed in the glucose/formaldehyde experiments while culture methanol levels increased.Fig. 4

Bottom Line: This approach resulted in a remarkably increased biomass yield on the primary substrate glucose when cultured in C-limited chemostats fed with a mixture of glucose and formaldehyde.With increasing relative formaldehyde feed concentrations, the biomass yield increased from 35% (C-mol biomass/C-mol glucose) without formaldehyde to 91% at 60% relative formaldehyde concentration.The RuMP-pathway expressing strain was also capable of growing to higher relative formaldehyde concentrations than the control strain.

View Article: PubMed Central - PubMed

Affiliation: B-Basic, Delft, The Netherlands. F.W.Koopman@tudelft.nl

ABSTRACT
The solvent-tolerant bacterium Pseudomonas putida S12 was engineered to efficiently utilize the C(1) compounds methanol and formaldehyde as auxiliary substrate. The hps and phi genes of Bacillus brevis, encoding two key steps of the ribulose monophosphate (RuMP) pathway, were introduced to construct a pathway for the metabolism of the toxic methanol oxidation intermediate formaldehyde. This approach resulted in a remarkably increased biomass yield on the primary substrate glucose when cultured in C-limited chemostats fed with a mixture of glucose and formaldehyde. With increasing relative formaldehyde feed concentrations, the biomass yield increased from 35% (C-mol biomass/C-mol glucose) without formaldehyde to 91% at 60% relative formaldehyde concentration. The RuMP-pathway expressing strain was also capable of growing to higher relative formaldehyde concentrations than the control strain. The presence of an endogenous methanol oxidizing enzyme activity in P. putida S12 allowed the replacement of formaldehyde with the less toxic methanol, resulting in an 84% (C-mol/C-mol) biomass yield. Thus, by introducing two enzymes of the RuMP pathway, co-utilization of the cheap and renewable substrate methanol was achieved, making an important contribution to the efficient use of P. putida S12 as a bioconversion platform host.

Show MeSH
Related in: MedlinePlus