John Hempel
University of Pittsburgh
52 Papers
951 Citations
John Hempel is an academic researcher from University of Pittsburgh. The author has contributed to research in topics: Aldehyde dehydrogenase & Dehydrogenase. The author has an hindex of 25, co-authored 52 publications.
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Papers
The first structure of an aldehyde dehydrogenase reveals novel interactions between NAD and the Rossmann fold.
Zhi-Jie Liu,Yuh-Ju Sun,John Rose,Yong-Je Chung,Chwan-Deng Hsiao,Wen-Rui Chang,Ingrid Kuo,John Perozich,Ronald Lindahl,John Hempel,Bi-Cheng Wang +10 more
TL;DR: Sequence comparisons of the class 3 ALDH with other ALDHs indicate a similar polypeptide fold, novel NAD-binding mode and catalytic site for this family, and a mechanism for enzymatic specificity and activity is postulated.
318
Aldehyde dehydrogenases: Widespread structural and functional diversity within a shared framework
TL;DR: Sequences of 16 NAD and/or NADP‐linked aldehyde oxidoreductases are aligned, including representative examples of all alde Hyde dehydrogenase forms with wide substrate preferences as well as additional types with distinct specificities for certain metabolic aldehydes.
179
Characterization of an alarm pheromone secreted by amphibian tadpoles that induces behavioral inhibition and suppression of the neuroendocrine stress axis.
Michael E. Fraker,Fang Hu,Vindhya Cuddapah,S. Andy McCollum,Rick A. Relyea,John Hempel,Robert J. Denver +6 more
TL;DR: It is shown that an alarm pheromone is produced by ranid tadpole skin cells, is released into the medium via an active secretory process upon predator attack, and signals predator presence to conspecifics, and a neuroendocrine mechanism is provided by which the behavioral inhibition caused by exposure to the alarms is maintained until the threat subsides.
172
Class III human liver alcohol dehydrogenase: a novel structural type equidistantly related to the class I and class II enzymes.
TL;DR: Drawings are made that the three classes of alcohol dehydrogenase reflect stages in the development of separate enzymes with distinct functional roles, and the similarity in the number of exchanges relative to that of the enzymes of the other two classes supports this conclusion.
131
Roles of conserved residues in the arginase family
TL;DR: A sequence alignment of 31 members of this family of arginases allowed the assignment of possible functional or structural roles to 32 conserved residues and conservative substitutions, and evolutionary relationships within this family were suggested.
95