Low-shear modeled microgravity affects metabolic networks of Escherichia coli O157:H7 EDL933: Further insights into space-microbiology consequences.

0557227 - BC 2023 RIV NL eng J - Journal Article
Kim, H.W. - Park, B.H. - Park, Hongjae - Baek, B.C. - Choi, I.G. - Rhee, M.S.
Low-shear modeled microgravity affects metabolic networks of Escherichia coli O157:H7 EDL933: Further insights into space-microbiology consequences.
Food Research International. Roč. 154, Apr (2022), č. článku 111013. ISSN 0963-9969. E-ISSN 1873-7145
Institutional support: RVO:60077344
Keywords : gene-expression * simulated microgravity * biofilm formation * stress-response * atcc 43889 * alters * virulence * growth * identification * typhimurium
OECD category: Microbiology
Impact factor: 8.1, year: 2022
Method of publishing: Limited access
https://doi.org/10.1016/j.foodres.2022.111013

Escherichia coli O157:H7 EDL933 exposed to low-shear modeled microgravity (LSMMG) and normal gravity (NG) was used for a transcriptomic analysis. The modified Gompertz model (R-2 = 0.81-0.99) showed an increased growth rate of E. coli O157:H7 under LSMMG. The mechanism of this active growth was associated with highly upregulated genes in nutrient and energy metabolism, including the TCA cycle, glycolysis, and pyruvate metabolism. Green fluorescent protein-labeled E. coli O157:H7 also formed significantly thick biofilms (fluorescent unit: NG, 1,263., LSMMG, 1,533., P = 0.0473) under LSMMG, whereas bacterial mobility decreased slightly (P = 0.0310). The transcriptomic analysis revealed that genes encoding glycogen biosynthesis (glgCAP operon) were upregulated (1.40 to 1.82 of log fold change [FC]) due to the downregulation of csrA (2.17 of log FC), which is the global regulator of biofilm formation of E. coli. We also identified 52 genes in E. coli O157:H7 EDL933 that were involved in the secretion pathway, 32 of which showed >= 2-fold significant changes in transcription levels after cultivation under LSMMG. Notably, all downregulated genes belonged to the type III and VI secretion systems, indicating that host cell contact secretion was dysregulated in the LSMMG cultures compared to the NG cultures. LSMMG also stimulates the pathogenicity of E. coli O157:H7 via transcriptional upregulation of Shiga toxin 1 (1.36 to 2.81 log FC) and toxin HokB (6.1 log FC). Our results suggest LSMMG affects bacterial growth, biofilm formation, and E. coli O157:H7 pathogenicity at some transcriptional levels, which indicates the importance of understanding biological consequences.
Permanent Link: https://hdl.handle.net/11104/0340788