Purification, Characterization, and Active Site Studies of 2-(2'-Hydroxyphenyl) Benzenesulfinate Desulfinase (DSZB) from Nocardia Asteroides Sp. Strain A3H1
| dc.contributor.advisor | Watkins, Linette M. | |
| dc.contributor.author | Vaz, Jerusha C. | |
| dc.contributor.committeeMember | Lewis, L. Kevin | |
| dc.contributor.committeeMember | Booth, Rachell E. | |
| dc.date.accessioned | 2018-02-19T22:26:22Z | |
| dc.date.available | 2018-02-19T22:26:22Z | |
| dc.date.issued | 2009-12 | |
| dc.description.abstract | Dibenzophene (DBT) and its complex heterocyclic derivatives comprise most of the sulfur that contaminates fossil fuels. The 2-(2´-hydroxyphenyl) benzenesulfinate desulfinase (DszB) enzyme metabolize sulfur from DBT compounds. DszB, one of the four enzymes of the desulfurizing pathway, catalyzes the carbon-sulfur bond cleavage in the last, and rate limiting step. The wildtype A3H1-DszB and the recombinant A3H1- R84Q-Y24Fand A3H1-R84Q-C27S DszBs from Nocarida asteroides sp. strain A3H1 were purified and characterized. The A3H1-R84Q-C27S- DszB was inactive. The temperature and pH optima for wildtype and A3H1-R84Q-Y24F DszBs were 35 ˚C and 8.5, respectively; the Km and kcat were 3.15 ± 0.74 µM and 1.24 ± 0.054 min-1, and 51.25 ± 0.96 µM and 4.33 ± 0.67 min-1, respectively. Overall, the A3H1-DszB showed a slower turnover rate and a moderately lower specificity for substrate when compared to the other DszB homologs referenced in this study. The mutant A3H1-R84Q-Y24F-DszB revealed that the enzyme was more susceptible to inhibition than the wildtype. Both DszBs were inhibited by 2,2-biphenol. Significant inhibition by a mixture of HBP and sulfite was observed in both enzymes. | en_US |
| dc.description.department | Chemistry and Biochemistry | |
| dc.format | Text | |
| dc.format.extent | 79 pages | |
| dc.format.medium | 1 file (.pdf) | |
| dc.identifier.citation | Vaz, J. C. (2009). <i>Purification, characterization, and active site studies of 2-(2'-hydroxyphenyl) benzenesulfinate desulfinase (DSZB) from Nocardia asteroides sp strain A3H1</i> (Unpublished thesis). Texas State University-San Marcos, San Marcos, Texas. | |
| dc.identifier.uri | https://hdl.handle.net/10877/6979 | |
| dc.language.iso | en | |
| dc.subject | DszB | en_US |
| dc.subject | HPBS desulfinase | en_US |
| dc.subject | Nocarida asteroides | en_US |
| dc.subject | A3H1 | en_US |
| dc.subject | DszB mechanism | en_US |
| dc.title | Purification, Characterization, and Active Site Studies of 2-(2'-Hydroxyphenyl) Benzenesulfinate Desulfinase (DSZB) from Nocardia Asteroides Sp. Strain A3H1 | en_US |
| dc.type | Thesis | |
| thesis.degree.department | Chemistry and Biochemistry | |
| thesis.degree.grantor | Texas State University-San Marcos | |
| thesis.degree.level | Masters | |
| thesis.degree.name | Master of Science |