Abbreviations
DAVID Database for Annotation, Visualization and Integrated Discovery
EASE Expression Analysis Systematic Explorer
EPS Extra polymeric substance
FPR False positive rate
fsr Fecal Streptococci regulator
GO Gene Ontology
KEGG Kyoto Encyclopedia of Gene and Genomes
LC-MS/MS Liquid Chromatography - Tandem Mass Spectrometry
LuxS S-ribosylhomocysteinase
PBS Phosphate buffered saline
PLGS ProteinLynx Global SERVER™
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The authors would like to thank Prof. M. Radhakrishna Pillai, Director, Rajiv Gandhi Centre for Biotechnology, for providing the necessary facilities. We also acknowledge Arun Surendran and Mahesh Chandran at the Mass Spectrometry and Proteomics Core Facility for technical assistance in LC-MS/MS analysis and also members of Confocal Imaging Core Facility for assistance in imaging. KS acknowledges Kerala State Council for Science, Technology & Environment, Government of Kerala for the fellowship provided.

Authors’ contributions
KS and ST conceived and designed the experiments. KS and LN performed the experiments, KS, JJ, SG and ST analyzed the results. KS and MPR drafted the manuscript. ST critically reviewed the manuscript. All authors read and approved the final manuscript.

Funding
This work is funded by Department of Biotechnology, Ministry of Science and Technology, Govt. of India (Grant no. BT/PR15261/MED/29/994/2015). The funding body had no role in the design of the study, analysis and interpretation of data and in writing the manuscript.

Availability of data and materials
The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD010770.

Ethics approval and consent to participate
The study was approved by the Institutional Human Ethics Committee (Reference number RGCB-IEC No. IHEC/01/2013/11) of Rajiv Gandhi Centre for Biotechnology. The participants were enrolled in this study after signing the informed consent protocol form. Animal Ethics clearance is not applicable, as this study does not involve any animals.

Consent for publication
Not applicable.

Competing interests
The authors declare that they have no competing interests.