Rapid Identification and Quantitative
Validation of a Caffeine-Degrading Pathway in Pseudomonas sp. CES
Chi Li Yu, Ryan M. Summers, Yalan Li, Sujit Kumar Mohanty, Mani Subramanian, and R. Marshall Pope
J. Proteome Res., 2015, Vol. 14(1), 95-106
With over 400 billion cups of coffee consumed each year, the environmental burden of the by-products is becoming a serious issue. This paper looks at microorganisms that can metabolize caffeine, potentially remediating some wastes, and uses proteomics methods to elucidate the enzyme pathways.
The authors performed quantitative comparisons of proteomes from bacteria grown in the absence and presence of caffeine using stable isotope dimethyl labeling and multiplexed LC-MS/MS assay. They discovered a number of caffeine-degrading enzymes in the CES strain with highly-induced capacity for caffeine degradation. The differences in the abundance of particular proteins were confirmed by reciprocal labeling experiments, and the role of the identified proteins in caffeine degradation was verified by genetic sequencing.