Rapid characterization of microbial biodegradation pathways by FT-IR spectroscopy.
Fourier transform-infrared (FT-IR) spectroscopy has become an important tool for rapid analysis of complex biological samples. The infrared absorbance spectrum could be regarded as a "fingerprint" which is characteristic of biochemical substances. In this study, Pseudomonas putida NCIMB 9869 was grown with either 3,5-xylenol or m-cresol as the sole carbon source, each inducing different metabolic pathways for m-cresol biotransformation. FT-IR spectroscopy was capable of differentiating both induced cultures of P. putida NCIMB 9869 as well as the resulting biotransformation product mixtures. FT-IR spectral analysis indicated that carboxylic acids were key chemicals responsible for distinguishing the products of the two catabolic pathways. Gas chromatography-mass spectrometry (GC-MS) was performed to validate the FT-IR analysis, indicating that two carboxylic acids, 3-hydroxybenzoic acid and 2,5-dihydroxybenzoic acid, were present as m-cresol biotransformation products from 3,5-xylenol-grown cells, but were absent in m-cresol-grown cells. The ability to use FT-IR to rapidly distinguish between biotransformation product mixtures as well as differentially induced bacterial strains suggests this approach might be a valuable tool for screening large biotransformation assays for novel products and metabolic mutants.
Huang
Wei E
WE
Molecular Microbial Ecology Laboratory, CEH-Oxford, Mansfield Road, Oxford, OX1 3SR, UK. whu@ceh.ac.uk
Hopper
David
D
Goodacre
Royston
R
Beckmann
Manfred
M
Singer
Andrew
A
Draper
John
J
D003408:Cresols / Q000378:metabolism*; D008401:Gas Chromatography-Mass Spectrometry; D025341:Principal Component Analysis; D016958:Pseudomonas putida / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*; D014992:Xylenes / Q000378:metabolism*
D003408:Cresols; D014992:Xylenes; C042041:3-cresol; C016834:3,5-xylenol