S-layer associated proteins contribute to the adhesive and immunomodulatory properties of Lactobacillus acidophilus NCFM

BMC Microbiology

article

Klotz, Courtney¹  Goh, Yong Jun²  O’Flaherty, Sarah²  Barrangou, Rodolphe¹ 

[1] Genomic Sciences Graduate Program North Carolina State University;Department of Food, Bioprocessing & Nutrition Sciences, North Carolina State University

关键词: Lactobacillus;    S-layer;    Probiotics;    Cell surface;   

DOI  :  10.1186/s12866-020-01908-2

学科分类：放射科、核医学、医学影像

来源: BioMed Central

【 摘 要 】

Surface layers (S-layers) are two-dimensional crystalline arrays of repeating proteinaceous subunits that form the outermost layer of many bacterial cell envelopes. Within the Lactobacillus genus, S-layer presence is frequently associated with probiotic-relevant properties such as improved adherence to host epithelial cells and modulation of the immune response. However, recent studies have demonstrated that certain S-layer functions may be supplemented by a novel subset of proteins embedded within its lattice, termed S-layer associated proteins (SLAPs). In the following study, four Lactobacillus acidophilus NCFM SLAPs (LBA0046, LBA0864, LBA1426, and LBA1539) were selected for in silico and phenotypic assessment. Despite lacking any sequence similarity or catalytic domains that may indicate function, the genes encoding the four proteins of interest were shown to be unique to S-layer-forming, host-adapted lactobacilli species. Likewise, their corresponding deletion mutants exhibited broad, host-relevant phenotypes including decreased inflammatory profiles and reduced adherence to Caco-2 intestinal cells, extracellular matrices, and mucin in vitro. Overall, the data presented in this study collectively links several previously uncharacterized extracellular proteins to roles in the underlying host adaptive mechanisms of L. acidophilus.

【 授权许可】

CC BY|CC0