Summary Vibrio cholerae is lethal to the model host Drosophila melanogaster through mechanisms not solely attributable to cholera toxin. To examine additional virulence determinants, we performed a genetic screen in V. cholerae-infected Drosophila and identified the two-component system CrbRS. CrbRS controls transcriptional activation of acetyl-CoA synthase-1 (ACS-1), and thus regulates the acetate switch, in which bacteria transition from excretion to assimilation of environmental acetate. The resultant loss of intestinal acetate leads to deactivation of host insulin signaling and lipid accumulation in enterocytes, resulting in host lethality. These metabolic effects are not observed upon infection with ΔcrbS or Δacs1 V. cholerae mutants. Additionally, uninfected flies lacking intestinal commensals, which supply short chain fatty acids (SCFA) such as acetate, also exhibit altered insulin signaling and intestinal steatosis, which is reversed upon acetate supplementation. Thus, acetate consumption by V. cholerae alters host metabolism, and dietary acetate supplementation may ameliorate some sequelae of cholera.

An outstanding tough, highly elastic, biodegradable, and thermostable hyperbranched epoxy was synthesized by a simple polycondensation reaction between a castor oil-based hyperbranched polyester polyol (HBPP) of monoglyceride of oil and bis(hydroxy methyl)propionic acid (Bis-MPA) and in situ-generated diglycidal ether of bisphenol A (DGEBA). The structure of HBPP was confirmed from FTIR, NMR, and different analytical studies. The formation of hyperbranched epoxy along with its structure was analyzed by different spectroscopic and analytical techniques. The poly(amido amine)-cured hyperbranched epoxy exhibited high tensile strength (42 MPa), extensibility (88% elongation), toughness (3144), scratch hardness (>10.0 kg), impact resistance (>100 cm), flexibility (bent up to 180°without damage), and biodegradation. The results indicate the strong influence of the amount of polyester polyol and bisphenol A on the performance of the thermosets. The study showed the superiority of the studied hyperbranched epoxy over the standard commercial bisphenol A-based epoxy (SBE) as well as the physically modified SBE with 10 wt % of HBPP. This biodegradable, elastic, and tough epoxy thermoset can be used as a sustainable advanced material.

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