Discovery of novel 3'-phosphoadenosine-5'-phosphosulfate (PAPS) reductase from methanarcheon Methanocaldococcus jannaschii.

dc.contributor.advisorKim, Sung-Kun, 1968-
dc.contributor.authorCho, Myung Kook.
dc.contributor.departmentChemistry and Biochemistry.en_US
dc.contributor.schoolsBaylor University. Dept. of Chemistry and Biochemistry.en_US
dc.date.accessioned2013-09-24T14:10:23Z
dc.date.accessioned2017-04-07T19:34:58Z
dc.date.available2013-09-24T14:10:23Z
dc.date.available2017-04-07T19:34:58Z
dc.date.copyright2013-08
dc.date.issued2013-09-24
dc.description.abstractThis study explores the potential assimilatory sulfate reduction pathway in methanarcheon by investigating the gene product of the open reading frame Mj0066. We expressed and purified the gene product of Mj0066 of Methanocaldococcus jannaschii to explore its substrate specificity and the reaction kinetics. Kinetic studies revealed the wild-type enzyme specifically reduced PAPS with E. coli thioredoxin supplied as the electron donor. The Kᵐ, V_max, and k_cat/Kᵐ value was 15.9 μM, 0.09429 μMmg⁻¹min⁻¹, and 5571 M⁻¹1s⁻¹, respectively, at pH 8.0 and 30°C. Therefore, the gene product of Mj0066 was identified as a novel 5’-phosphoadenosine-phosphosulfate reductase. Furthermore, site directed mutagenesis of individual cysteines and redox titration were performed in order to investigate the catalytic mechanism. The combined studies show Cys337 plays a role in substrate binding while Cys19 and Cys22 are involved in electron transfer. Taken together, PAPS-reductase activity advocates the presence of a PAPS-utilizing assimilatory sulfate reduction pathway M. jannaschii.en_US
dc.description.degreeM.S.en_US
dc.identifier.urihttp://hdl.handle.net/2104/8817
dc.language.isoen_USen_US
dc.publisheren
dc.rightsBaylor University theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. Contact librarywebmaster@baylor.edu for inquiries about permission.en_US
dc.rights.accessrightsWorldwide accessen_US
dc.titleDiscovery of novel 3'-phosphoadenosine-5'-phosphosulfate (PAPS) reductase from methanarcheon Methanocaldococcus jannaschii.en_US
dc.typeThesisen_US

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