In recent years, naturally occurring darobactins have emerged as a promising compound class to combat infections caused by critical Gram-negative pathogens. In this study, we describe the in vivo evaluation of derivative D22, a non-natural biosynthetic darobactin analogue with significantly improved antibacterial activity. We found D22 to be active in vivo against key critical Gram-negative human pathogens, as demonstrated in murine models of thigh infection, peritonitis/sepsis, and urinary tract infection (UTI).
View Article and Find Full Text PDFUnlabelled: The continued emergence of strains that express resistance to multiple antibiotics, including the last drug for empiric monotherapy (ceftriaxone), necessitates the development of new treatment options to cure gonorrheal infections. Toward this goal, we recently reported that corallopyronin A (CorA), which targets the switch region of the β' subunit (RpoC) of bacterial DNA-dependent RNA polymerase (RNAP), has potent anti-gonococcal activity against a panel of multidrug-resistant clinical strains. Moreover, in that study, CorA could eliminate gonococcal infection of primary human epithelial cells and gonococci in a biofilm state.
View Article and Find Full Text PDFToxicological studies are a part of the drug development process and the preclinical stages, for which suitable vehicles ensuring easy and safe administration are crucial. However, poor aqueous solubility of drugs complicates vehicle screening for oral administration since non-aqueous solvents are often not tolerable. In the case of the anti-infective corallopyronin A, currently undergoing preclinical investigation for filarial nematode and bacterial infections, commonly used vehicles such as polyethylene glycol 200, aqueous solutions combined with cosolvents or solubilizers, or aqueous suspension have failed due to insufficient tolerability, solubility, or the generation of a non-homogeneous suspension.
View Article and Find Full Text PDFThe natural product chlorotonil displays high potency against multidrug-resistant Gram-positive bacteria and Plasmodium falciparum. Yet, its scaffold is characterized by low solubility and oral bioavailability, but progress was recently made to enhance these properties. Applying late-stage functionalization, we aimed to further optimize the molecule.
View Article and Find Full Text PDFMethicillin-resistant Staphylococcus aureus (MRSA) is a World Health Organization’s high priority pathogen organism, with an estimated > 100,000 deaths worldwide in 2019. Thus, there is an unmet medical need for novel and resistance-breaking anti-infectives. The natural product Co-rallopyronin A (CorA), currently in preclinical development for filariasis, is efficacious against MRSA in vitro.
View Article and Find Full Text PDFIn vivo studies in mice provide a valuable model to test novel active pharmaceutical ingredients due to their low material need and the fact that mice are frequently used as a species for early efficacy models. However, preclinical in vitro evaluations of formulation principles in mice are still lacking. The development of novel in vitro and in silico models supported the preclinical formulation evaluation for the anti-infective corallopyronin A (CorA).
View Article and Find Full Text PDFCorallopyronin A (CorA) is active against Gram-positive bacteria and targets the switch region of RNA polymerase. Because of the high frequency of mutation (FoM) leading to rifampicin resistance, we determined the CorA FoM in S. aureus using fluctuation analysis at 4 × minimum inhibitory concentration (MIC).
View Article and Find Full Text PDFDuring submerged cultivation, the edible basidiomycete (previously ) developed a fruity odor, strongly reminding of pineapple. Olfactometric analysis showed that this impression was mainly caused by the two (5/,7,9)-decatrien-2-ones. At the time of maximum concentration on the 5th day, the (5/5)-ratio was 94:6.
View Article and Find Full Text PDFDuring the cultivation of the edible mushroom on agro-industrial side streams, a pleasant flavor strongly reminiscent of pineapple was perceived. Aroma extract dilution analyses identified two flavor components with a distinct pineapple odor. On the basis of mass spectrometric data, a Wittig reaction of ()-penta-2,4-dien-1-yltriphosphonium bromide with ethyl levulinate was conducted.
View Article and Find Full Text PDF, a potent fungal sesquiterpene producer, was grown Cerrena unicolor, as a model organism in submerged culture to search for chemicals affecting sesquiterpene biosynthesis in vitro. Thirty-one sesquiterpenes and sesquiterpenoids were identified in the supernatant, among them the fruity α-ylangene as the main volatile. Additives, such as some polysaccharides or lipids, did not affect the qualitative product spectrum but strongly affected the quantitative synthesis.
View Article and Find Full Text PDFBuried explosive material, e.g., landmines, represent a severe issue for human safety all over the world.
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