Structural Characterization of the Lactobacillus Plantarum FlmC Protein Involved in Biofilm Formation

October 11, 2018

Title

Structural Characterization of the Lactobacillus Plantarum FlmC Protein Involved in Biofilm Formation

Author

Gianluca D’Abrosca, Antonella Paladino, Emilio Cuoco, Rosangela Marasco, Severina Pacifico, Simona Piccolella, Valeria Vastano, Margherita Sacco, Carla Isernia, Lidia Muscariello, Gaetano Malgieri

Year

2018

Journal

Molecules

Abstract

Lactobacillus plantarum is one of the most predominant species in the human gut microbiota of healthy individuals. We have previously characterized some probiotic features of L. plantarum LM3, as the high resistance to different stress, the binding ability toward some extracellular matrix proteins and plasminogen and the immunomodulatory role of the surface expressed adhesin EnoA1. We have also identified the flmA, flmB and flmC genes, coding for putative proteins named FlmA, FlmB and FlmC, whose null mutations partially impaired biofilm development; the L. plantarum LM3–6 strain, carrying a deletion in flmC, showed a high rate of autolysis, supporting the hypothesis that FlmC might be involved in cell wall integrity. Here, we report the in-silico characterization of ΔTM-FlmC, a portion of the FlmC protein. The protein has been also expressed, purified and characterized by means of CD spectroscopy, ICP-mass and UHPLC-HRMS. The obtained experimental data validated the predicted model unveiling also the presence of a bound lipid molecule and of a Mg(II) ion. Overall, we provide strong evidences that ΔTM-FlmC belongs to the LytR-CpsA-Psr (LCP) family of domains and is involved in cell envelope biogenesis.

Instrument

J-815

Keywords

Circular dichroism, Secondary structure, Protein folding, Thermal stability, Biochemistry