Publications by authors named "Kyra Geyer"

Polyketide synthases (PKSs) are molecular assembly lines that condense basic chemical building blocks for the production of structurally diverse polyketides. Many PKS biosynthetic gene clusters contain a gene encoding for a type II thioesterase (TEII). It is believed that TEIIs exert a proofreading function and restore or increase the productivity of PKSs by removing aberrant modifications on the acyl-carrier proteins (ACPs) of the PKS assembly line.

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Polyketide synthases (PKSs) use simple extender units to synthesize complex natural products. A fundamental question is how different extender units are site-specifically incorporated into the growing polyketide. Here we established phoslactomycin (Pn) PKS, which incorporates malonyl- and ethylmalonyl-CoA, as an in vitro model to study substrate specificity.

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Bacteria frequently adapt to high osmolarity surroundings through the accumulation of compatible solutes. Ectoine is a prominent member of these types of stress protectants and is produced via an evolutionarily conserved biosynthetic pathway beginning with the L-2,4-diaminobutyrate (DAB) transaminase (TA) EctB. Here, we studied EctB from the thermo-tolerant Gram-positive bacterium () and show that this tetrameric enzyme is highly tolerant to salt, pH, and temperature.

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The incorporation of different extender units generates structural diversity in polyketides. There is significant interest in engineering substrate specificity of polyketide synthases (PKSs) to change their chemical structure. Efforts to change extender unit selectivity are hindered by the lack of simple screening methods and easily available atypical extender units.

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