Analysis of the molecular response of Pseudomonas putida KT2440 to the next-generation biofuel n-butanol

Publication Type

Journal contribution (peer reviewed)

Authors

Simon, O., Klebensberger, J., Mükschel, B., Klaiber, I., Graf, N., Altenbuchner, J., Huber, A., Hauer, B., and Pfannstiel, J.

Year of publication

2015

Published in

Journal of Proteomics

DOI

10.1016/j.jprot.2015.03.022

Page (from - to)

11-25

To increase the efficiency of biocatalysts a thorough understanding of the molecular response of the biocatalyst to precursors, products and environmental conditions applied in bioconversions is essential. Here we performed a comprehensive proteome and phospholipid analysis to characterize the molecular response of the potential biocatalyst Pseudomonas putida KT2440 to the next-generation biofuel n-butanol. Using complementary quantitative proteomics approaches we were able to identify and quantify 1467 proteins, corresponding to 28% of the total KT2440 proteome. 256 proteins were altered in abundance in response to n-butanol. The proteome response entailed an increased abundance of enzymes involved in n-butanol degradation including quinoprotein alcohol dehydrogenases, aldehyde dehydrogenases and enzymes of fatty acid beta oxidation. From these results we were able to construct a pathway for the metabolism of n-butanol in P. putida. The initial oxidation of n-butanol is catalyzed by at least two quinoprotein ethanol dehydrogenases (PedE and PedH). Growth of mutants lacking PedE and PedH on n-butanol was significantly impaired, but not completely inhibited, suggesting that additional alcohol dehydrogenases can at least partially complement their function in KT2440. Furthermore, phospholipid profiling revealed a significantly increased abundance of lyso-phospholipids in response to n-butanol, indicating a rearrangement of the lipid bilayer.