Publications by authors named "W E Karsten"

Dihydrodipicolinate synthase (DHDPS) catalyzes the first committed step in the lysine-biosynthetic pathway converting pyruvate and L-aspartate-β-semialdehyde to dihydrodipicolinate. Kinetic studies indicate that the pyruvate analog (S)-2-bromopropionate inactivates the enzyme in a pseudo-first-order process. An initial velocity pattern indicates that (S)-2-bromopropionate is a competitive inhibitor versus pyruvate, with an inhibition constant of about 8 mM.

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Dihydrodipicolinate synthase (DHDPS) catalyzes the first step in the biosynthetic pathway for production of l-lysine in bacteria and plants. The enzyme has received interest as a potential drug target owing to the absence of the enzyme in mammals. The DHDPS reaction is the rate limiting step in lysine biosynthesis and involves the condensation of l-aspartate-β-semialdehyde and pyruvate to form 2, 3-dihydrodipicolinate.

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Dihydrodipicolinate synthase (DHDPS) catalyzes the first step in the pathway for the biosynthesis of L-lysine in most bacteria and plants. The substrates for the enzyme are pyruvate and L-aspartate-β-semialdehyde (ASA). The product of the reaction was originally proposed to be 2,3-dihydrodipicolinate (DHDP), but has now generally been assumed to be (4S)-4-hydroxy-2,3,4,5-tetrahydro-(2S)-dipicolinate (HTPA).

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The enzyme dihydrodipicolinate reductase (DHDPR) is a component of the lysine biosynthetic pathway in bacteria and higher plants. DHDPR catalyzes the NAD(P)H dependent reduction of 2,3-dihydrodipicolinate to the cyclic imine L-2,3,4,5,-tetrahydropicolinic acid. The dapB gene that encodes dihydrodipicolinate reductase has previously been cloned, but the expression of the enzyme is low and the purification is time consuming.

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Purpose: The aim of this study was to evaluate the possibility of using the zygomatic buttress as an intraoral bone harvesting donor site and determine the safety of this harvesting procedure for later optimal positioning of dental implants in accordance with prosthodontic and functional principles.

Material And Methods: A consecutive retrospective study was conducted on patients who had been treated at the Department of Oral and Maxillofacial Surgery of Ulm military and academic hospital, over a 3-year period (January 2008 to December 2010). Medical history, smoking status, area of surgery, and complications were recorded.

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