Gene profiling-based phenotyping for identification of cellular parameters that contribute to fitness, stress-tolerance and virulence of Listeria monocytogenes variants

Abstract

Microbial population heterogeneity allows for a differential microbial response to environmental stresses and can lead to the selection of stress resistant variants. In this study, we have used two different stress resistant variants of Listeria monocytogenes LO28 with mutations in the rpsU gene encoding ribosomal protein S21, to elucidate features that can contribute to fitness, stress-tolerance and host interaction using a comparative gene profiling and phenotyping approach. Transcriptome analysis showed that 116 genes were upregulated and 114 genes were downregulated in both rpsU variants. Upregulated genes included a major contribution of SigB-controlled genes such as intracellular acid resistance-associated glutamate decarboxylase (GAD) (gad3), genes involved in compatible solute uptake (opuC), glycerol metabolism (glpF, glpK, glpD), and virulence (inlA, inlB). Downregulated genes in the two variants involved mainly genes involved in flagella synthesis and motility. Phenotyping results of the two rpsU variants matched the gene profiling data including enhanced freezing resistance conceivably linked to compatible solute accumulation, higher glycerol utilisation rates, and better adhesion to Caco 2 cells presumably linked to higher expression of internalins. Also, bright field and electron microscopy analysis confirmed reduced flagellation of the variants. The activation of SigB-mediated stress defence offers an explanation for the multiple-stress resistant phenotype in rpsU variants.

Mechanisms underlying the virulence regulation of new Vibrio alginolyticus ncRNA Vvrr1 with a comparative proteomic analysis

“…sdhB (succinate dehydrogenase iron-sulfur subunit encoding gene) is found to be necessary for the adhesion and biofilm formation in Staphylococcus aureus [62]. glpF (glycerol uptake facilitator protein-encoding gene) participates in L. monocytogenes biofilm formation at the air-liquid interface [63] and adhesion to Caco-2 cells [64]. cysH (phosphoadenosine phosphosulfate reductase encoding gene) is related to the regulation of adhesion and biofilm formation in E. coli [65].…”

Comparative Proteomics Demonstrates Altered Metabolism Pathways in Cotrimoxazole- Resistant and Amikacin-Resistant Klebsiella pneumoniae Isolates

“…( Supplementary Figure 1B ). rpsU, also known as ribosomal protein S21 (rps21), was reported to contribute to fitness, stress-tolerance and host interaction ( Koomen et al, 2018 ). HupA (heat-unstable α, HUα) is a subunit of a heterotypic dimer, Huαβ, resulting in high growth and a lowly pleiotropic phenotype ( Abebe et al, 2017 ).…”

Cucumber Ribosomal Protein CsRPS21 Interacts With P22 Protein of Cucurbit Chlorotic Yellows Virus

“…Besides, plastid RPS21 plays role in the response to C/N balance ( Dong et al, 2020 ). In microorganisms, S21 is involved in stress resistance, growth, and motility ( Akanuma et al, 2012 ; Metselaar et al, 2015 ; Koomen et al, 2018 ). Different RPs like RPL10, RPL13, RPL18, RPL24, and RPS6 are involved in viral infections of plants ( Bureau et al, 2004 ; Rocha et al, 2008 ; Hafren et al, 2013 ; Zorzatto et al, 2015 ; Chen et al, 2016 ; Ivanov et al, 2016 ; Rajamaki et al, 2017 ; Li et al, 2018 ).…”