TY - JOUR

T1 - LptD depletion disrupts morphological homeostasis and upregulates carbohydrate metabolism in Escherichia coli

AU - Frisinger, Frida Svanberg

AU - Jana, Bimal

AU - Ortiz-Marquez, Juan C.

AU - Van Opijnen, Tim

AU - Donadio, Stefano

AU - Guardabassi, Luca

N1 - Publisher Copyright: © 2023 The Author(s).

PY - 2023

Y1 - 2023

N2 - In a previous in silico study, we identified an essential outer membrane protein (LptD) as an attracti v e target for development of nov el antibiotics. Her e , w e c har acterized the effects of LptD depletion on Esc heric hia coli physiolo gy and morpholo gy. An E. coli CRISPR interference (CRISPRi) strain was constructed to allow control of lptD expression. Induction of the CRISPRi system led to ∼440-fold reduction of gene expression. Dose-dependent growth inhibition was observed, where strong knockdown effectively inhibited initial growth but partial knockdown exhibited maximum overall killing after 24 h. LptD depletion led to morphological changes where cells exhibited long, filamentous cell shapes and cytoplasmic accumulation of lipopolysacc haride (LPS). Tr anscriptional profiling by RN A-Seq show ed that LptD knoc kdown led to upre gulation of carbohydr ate meta bolism, especiall y in the colanic acid biosynthesis pathw ay. This pathw ay w as further ov er expr essed in the pr esence of sub lethal concentrations of colistin, an antibiotic targeting LPS, indicating a specific transcriptional response to this synergistic envelope damage. Additionally, exposure to colistin during LptD de pletion r esulted in downr egulation of pathw ays r elated to motility and c hemotaxis, tw o important virulence tr aits. Altogether, these results show that LptD depletion (i) affects E. coli survi v al, (ii) upr e gulates carbohydr ate metabolism, and (iii) synergizes with the antimicrobial activity of colistin.

AB - In a previous in silico study, we identified an essential outer membrane protein (LptD) as an attracti v e target for development of nov el antibiotics. Her e , w e c har acterized the effects of LptD depletion on Esc heric hia coli physiolo gy and morpholo gy. An E. coli CRISPR interference (CRISPRi) strain was constructed to allow control of lptD expression. Induction of the CRISPRi system led to ∼440-fold reduction of gene expression. Dose-dependent growth inhibition was observed, where strong knockdown effectively inhibited initial growth but partial knockdown exhibited maximum overall killing after 24 h. LptD depletion led to morphological changes where cells exhibited long, filamentous cell shapes and cytoplasmic accumulation of lipopolysacc haride (LPS). Tr anscriptional profiling by RN A-Seq show ed that LptD knoc kdown led to upre gulation of carbohydr ate meta bolism, especiall y in the colanic acid biosynthesis pathw ay. This pathw ay w as further ov er expr essed in the pr esence of sub lethal concentrations of colistin, an antibiotic targeting LPS, indicating a specific transcriptional response to this synergistic envelope damage. Additionally, exposure to colistin during LptD de pletion r esulted in downr egulation of pathw ays r elated to motility and c hemotaxis, tw o important virulence tr aits. Altogether, these results show that LptD depletion (i) affects E. coli survi v al, (ii) upr e gulates carbohydr ate metabolism, and (iii) synergizes with the antimicrobial activity of colistin.

KW - carbohydrate metabolism

KW - colanic acid

KW - colistin

KW - Escherichia coli

KW - LptD

U2 - 10.1093/femsmc/xtad013

DO - 10.1093/femsmc/xtad013

M3 - Journal article

C2 - 37701421

AN - SCOPUS:85177495753

VL - 4

JO - FEMS Microbes

JF - FEMS Microbes

SN - 2633-6685

M1 - xtad013

ER -