Role of Post-Translational Protein Modification in Community-Scale Processes

The Science

Although biological processes are often modulated by the direct regulation of gene expression, post-translational modifications (PTM) of expressed proteins frequently play an equally important regulatory role. PTM occurs when protein function is altered by the addition of a phosphate, acetate, or other small molecule in response to a sensed environmental cue. These alterations create rippling signal cascades, often leading to pervasive changes in cellular metabolism and functional properties. PTM-based regulation has been extensively studied in individual organisms, but the role of this regulatory mechanism at the scale of complex communities remains poorly understood. In a new study, a collaborative team of researchers at the University of California–Berkeley, and Oak Ridge National Laboratory developed a novel technique that allows PTM analysis in proteins collected from an intact microbial community (i.e., the metaproteome) using high-resolution mass spectrometry coupled to high-performance computing. The investigators examined PTM in a model biofilm community found in a highly acidic environment and were able to link this regulatory mechanism to several community-scale phenotypes that could not be explained by observed changes in gene expression. Community-level attributes associated with PTM in this study included alterations in community structure, nutrient acquisition strategies, and resistance to viral invasion.

The Impact

This finding represents a considerable advance in the application of systems biology approaches to community-level analysis. The team now is working to scale up this technique to enable investigations of more complex communities and environments.

Principal Investigator

Jillian Banfield

Co-Principal Investigator

Chongle Pan


Li, Z., Y. Wang, Q. Yao, N. B. Justice, T.-H. Ahn, D. Xu, R. L. Hettich, J. F. Banfield, and C. Pan. 2014. “Diverse and Divergent Protein Post Translational Modifications in Two Growth Stages of a Natural Microbial Community,” Nature Communications 5, 4405. DOI: 10.1038/ncomms5405.