Metabolome and proteome changes between biofilm and planktonic phenotypes of the marine bacterium Pseudoalteromonas lipolytica TC8

Abstract

A number of bacteria adopt various lifestyles such as planktonic free-living or sessile biofilm stages. This enables their survival and development in a wide range of contrasting environments. With the aim of highlighting specific metabolic shifts between these phenotypes and to improve the overall understanding of marine bacterial adhesion, a dual metabolomics/proteomics approach was applied to planktonic and biofilm cultures of the marine bacterium Pseudoalteromonas lipolytica TC8. The liquid chromatography mass spectrometry (LC-MS) based metabolomics study indicated that membrane lipid composition was highly affected by the culture mode: phosphatidylethanolamine (PEs) derivatives were over-produced in sessile cultures while ornithine lipids (OLs) were more specifically synthesized in planktonic samples. In parallel, differences between proteomes revealed that peptidases, oxidases, transcription factors, membrane proteins and the enzymes involved in histidine biosynthesis were over-expressed in biofilms while proteins involved in heme production, nutrient assimilation, cell division and arginine/ornithine biosynthesis were specifically up-regulated in free-living cells.

Keywords:

• Pseudoalteromonas lipolytica TC8
• metabolomics
• proteomics
• biofilms
• liquid chromatography-mass spectrometry
• membrane lipids

Acknowledgements

The authors are grateful to R. Gandolfo for the kind support of the French Mediterranean Marine Competitivity Centre (Pôle Mer Méditerranée) and Dr S. Greff for the UPLC-HRMS analyses. The LC-MS experiments were conducted on the regional platform MALLABAR (Institute of Ecology and Environment – INEE of the National Center for Scientific Research – CNRS and ‘Provence-Alpes-Côte d’Azur – PACA’ regional council supports). O. B.-S. acknowledges support from the Région Midi‐Pyrénées, European funds (Fonds Européens de Développement Régional - FEDER), Toulouse Métropole, and the French Ministry of Research with the ‘Investissement d’Avenir Infrastructures Nationales en Biologie et Santé’ program (Proteomics French Infrastructure project – ProFI; Project number: ANR-10-INBS-08).