Publications by authors named "Karen J Breese"

Dicamba is a popular herbicide with rising use but is also notorious for volatility drift. Inspired by meclofenoxate, which we show to be highly herbicidal, we developed a derivative of dicamba with an ester-bond to 2-dimethylaminoethanol. It remained herbicidal but is non-volatile, entering plants intact and hydrolyzing inside leaves to dicamba and 2-dimethylaminoethanol.

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Hexosaminidases are key enzymes in glycoconjugate metabolism and occur in all kingdoms of life. Here, we have investigated the phylogeny of the GH20 glycosyl hydrolase family in nematodes and identified a β-hexosaminidase subclade present only in the Dorylaimia. We have expressed one of these, HEX-2 from , a porcine parasite, and shown that it prefers an aryl β--acetylgalactosaminide .

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Article Synopsis
  • New drugs for treating visceral leishmaniasis are urgently needed, but there haven't been many suitable candidates developed recently.
  • DNDI-6174 is a promising new compound derived from a specific chemical series that shows strong potential against various species of the parasite causing the disease.
  • Preliminary studies on DNDI-6174 indicate it has good safety and effectiveness, making it a viable option for further preclinical development.
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Article Synopsis
  • Bacteria can develop resistance to antibiotics through various mechanisms, which can be monitored by laboratory tests.
  • This study identifies a specific resistance mechanism in Group A Streptococcus that uses a gene (thfT) to acquire nutrients from the host, allowing it to bypass the antibiotic sulfamethoxazole's effects.
  • Understanding these resistance mechanisms during infections is crucial to reduce ineffective antibiotic use and limit the spread of resistance among bacteria.
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Decades of intense herbicide use has led to resistance in weeds. Without innovative weed management practices and new herbicidal modes of action, the unabated rise of herbicide resistance will undoubtedly place further stress upon food security. HMGR (3-hydroxy-3-methylglutaryl-coenzyme A reductase) is the rate limiting enzyme of the eukaryotic mevalonate pathway successfully targeted by statins to treat hypercholesterolemia in humans.

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Herbicides are vital for modern agriculture, but their utility is threatened by genetic or metabolic resistance in weeds, as well as regulatory barriers. Of the known herbicide modes of action, 7,8-dihydropterin synthase (DHPS), which is involved in folate biosynthesis, is targeted by just one commercial herbicide, asulam. A mimic of the substrate para-aminobenzoic acid, asulam is chemically similar to sulfonamide antibiotics, and although it is still in widespread use, asulam has faced regulatory scrutiny.

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The rise in herbicide resistance over recent decades threatens global agriculture and food security and so discovery of new modes of action is increasingly important. Here we reveal linezolid, an oxazolidinone antibiotic that inhibits microbial translation, is also herbicidal. To validate the herbicidal mode of action of linezolid we confirmed its micromolar inhibition is specific to chloroplast translation and did not affect photosynthesis directly.

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