High Osmotic Stress Increases OmpK36 Expression through the Regulation of KbvR to Decrease the Antimicrobial Resistance of Klebsiella pneumoniae

Wang, Meng; Tian, Yujiao; Xu, Li; Zhang, Fusheng; Lu, Huigai; Li, Yaqian; Li, Bei

doi:10.1128/spectrum.00507-22

Cited by 4 publications

(3 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since resistance against β-lactams is acquired by the production of β-lactamases, it could be that localization of these enzymes in the membrane of A. baumannii is, to some extent, disturbed by an altered lipid composition of the inner membrane or that diffusion of the antibiotic over a disturbed inner membrane is facilitated, thereby affecting the susceptibility for antibiotics such as imipenem. It is interesting that WE/TAG production is induced during growth in the presence of a high salt concentration, and the interplay between antibiotic resistance and osmotic stress resistance has been discussed for different bacteria. ,, Especially in the food industry, where high salt concentrations are used as preservatives, the antibiotic cross-resistance induced by osmotic stress has been investigated. , Our data emphasize the role of WEs and TAGs as flexible pools/deposits for FAs or FALs over the function for water, carbon, or energy storage. While the loss of WEs and TAGs did not lead to a significant loss of viability under desiccation and starvation conditions, disturbance of WE and TAG production had an effect on antibiotic and ROS sensitivity as well as growth under salt stress.…”

Section: Discussionmentioning

confidence: 74%

“…It is interesting that WE/TAG production is induced during growth in the presence of a high salt concentration, and the interplay between antibiotic resistance and osmotic stress resistance has been discussed for different bacteria. 15,49,50 Especially in the food industry, where high salt concentrations are used as preservatives, the antibiotic crossresistance induced by osmotic stress has been investigated. 51,52 Our data emphasize the role of WEs and TAGs as flexible pools/deposits for FAs or FALs over the function for water, carbon, or energy storage.…”

Section: ■ Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Wax Ester and Triacylglycerol Production in Acinetobacter baumannii: Role in Osmostress Protection, Reactive Oxygen Species, and Antibiotic Sensitivity

Pfefferle,

Averhoff

2023

ACS Infect. Dis.

View full text Add to dashboard Cite

Wax esters (WEs) are neutral lipids that are produced by many different bacteria as potential carbon and energy storage compounds. Comparatively little is known about the role of WE in pathogenic bacteria. The opportunistic pathogen Acinetobacter baumannii is a major cause of hospital-acquired infections worldwide. Salt and desiccation resistance foster A. baumannii infections such as urinary tract infections and allow for reinfection when bacteria are taken up from dry surfaces in the hospital environment. Here we report on WE and triacylglycerol (TAG) production in A. baumannii as a response to nitrogen limitation and high salt stress. Fatty acids and fatty alcohols with chain lengths of C16 and C18 were identified as the most prominent WE constituents. We identified the terminal key enzyme of WE biosynthesis, the bifunctional wax ester synthase/acylCoA:diacylglycerol acyltransferase (WS/DGAT) encoded by the wax/dgat gene, and demonstrated that transcription of wax/dgat and production of WS/DGAT are independent of the nitrogen concentration. A Δwax/dgat mutant was impaired in growth in the presence of high salt concentration and was more sensitive to imipenem and reactive oxygen species.

show abstract

Section: Discussionmentioning

confidence: 74%

Section: ■ Discussionmentioning

confidence: 99%

Wax Ester and Triacylglycerol Production in Acinetobacter baumannii: Role in Osmostress Protection, Reactive Oxygen Species, and Antibiotic Sensitivity

Pfefferle,

Averhoff

2023

ACS Infect. Dis.

View full text Add to dashboard Cite

show abstract

“…One of the reasons for the production of outer membrane proteins is osmotic stress caused by salts, sugars, pH value, and temperature, which activates the gene involved in the expression of those proteins [ 28 , 29 ]. In Klebsiella pneumoniae , for example, high osmotic stress causes the KbvR to be upregulated, which increases the expression of OmpK36 [ 30 ]. Moreover, higher levels of osmotic stress caused by NaCl impact OmpC expression increases Escherichia coli ’s kanamycin resistance [ 31 , 32 ].…”

Section: Introductionmentioning

confidence: 99%

Outer membrane protein N expressed in Gram-negative bacterial strain of Escherichia coli BL21 (DE3) Omp8 Rosetta strains under osmoregulation by salts, sugars, and pHs

Chumjan,

Sangchalee,

Somwang

et al. 2023

PLoS ONE

View full text Add to dashboard Cite

This study presented the expression of the outer membrane protein N in E. coli BL21 (DE3) Omp8 Rosetta under its growth condition and by osmoregulation. The effects of osmotic stress caused by salts, sugars, or pH values on the survival of the target Gram-negative bacterial strain of E. coli BL21 (DE3) Omp8 Rosetta and OmpN expression remain unknown. Here, tryptone yeast extract with varied salts and concentrations was initially used to generate an LB broth medium. To show how salts and concentration affect bacterial growth, the optical density at 600 nm was measured. The findings supported the hypothesis that salts and concentrations control bacterial growth. Moreover, a Western blotting study revealed that OmpN overexpression was present in all tested salts after stimulation with both glucose and fructose after being treated individually with anti-OmpN and anti-histidine tag polyclonal antibodies on transferred nitrocellulose membrane containing crude OmpN. Following the presence of the plasmid pET21b(+)/ompN-BOR into E. coli BL21 (DE3) Omp8 Rosetta, which was expressed in the recombinant OmpN protein (BOR), OmpN expression was demonstrated for all monovalent cations as well as MgCl2. All of the tested salts, except for BaCl2, NaH2PO4, and KH2PO4, showed overexpression of recombinant BOR after Isopropyl β-D-1-thiogalactopyranoside (IPTG) induction. Using CH3COONa, both with and without IPTG induction, there was very little bacterial growth and no OmpN expression. With NaCl, a pH value of 7 was suitable for bacterial development, whereas KCl required a pH value of 8. According to this research, bacterial growth in addition to salts, sugars, and pH values influences how the OmpN protein is produced.

show abstract

Harnessing regulatory networks in Actinobacteria for natural product discovery

Augustijn,

Roseboom,

Medema

et al. 2024

Journal of Industrial Microbiology and Biotechnology

View full text Add to dashboard Cite

Microbes typically live in complex habitats where they need to rapidly adapt to continuously changing growth conditions. To do so, they produce an astonishing array of natural products with diverse structures and functions. Actinobacteria stand out for their prolific production of bioactive molecules, including antibiotics, anticancer agents, antifungals, and immunosuppressants. Attention has been directed especially towards the identification of the compounds they produce and the mining of the large diversity of biosynthetic gene clusters (BGCs) in their genomes. However, the current return on investment in random screening for bioactive compounds is low, while it is hard to predict which of the millions of BGCs should be prioritized. Moreover, many of the BGCs for yet undiscovered natural products are silent or cryptic under laboratory growth conditions. To identify ways to prioritize and activate these BGCs, knowledge regarding the way their expression is controlled is crucial. Intricate regulatory networks control global gene expression in Actinobacteria, governed by a staggering number of up to 1000 transcription factors per strain. This review highlights recent advances in experimental and computational methods for characterizing and predicting transcription factor binding sites and their applications to guide natural product discovery. We propose that regulation-guided genome mining approaches will open new avenues toward eliciting the expression of BGCs, as well as prioritizing subsets of BGCs for expression using synthetic biology approaches. One-Sentence Summary This review provides insights into advances in experimental and computational methods aimed at predicting transcription factor binding sites and their applications to guide natural product discovery.

show abstract

High Osmotic Stress Increases OmpK36 Expression through the Regulation of KbvR to Decrease the Antimicrobial Resistance of Klebsiella pneumoniae

Cited by 4 publications

References 45 publications

Wax Ester and Triacylglycerol Production in Acinetobacter baumannii: Role in Osmostress Protection, Reactive Oxygen Species, and Antibiotic Sensitivity

Wax Ester and Triacylglycerol Production in Acinetobacter baumannii: Role in Osmostress Protection, Reactive Oxygen Species, and Antibiotic Sensitivity

Outer membrane protein N expressed in Gram-negative bacterial strain of Escherichia coli BL21 (DE3) Omp8 Rosetta strains under osmoregulation by salts, sugars, and pHs

Harnessing regulatory networks in Actinobacteria for natural product discovery

Contact Info

Product

Resources

About