Production of nitrile hydrolysing biocatalysts from Rhodococcus rhodochrous

Simple item page
dc.contributor.authorSoobben, Marushka
dc.date.accessioned2021-04-24T12:05:30Z
dc.date.available2021-04-24T12:05:30Z
dc.date.issued2020
dc.descriptionA dissertation Submitted in fulfilment of the requirements for the degree Master of Science in Molecular and Cell Biology in the Faculty of Science, University of the Witwatersrand, Johannesburg, 2020en_ZA
dc.description.abstractBiocatalysis plays an important role in initiating environmentally-friendly processes during chemical synthesis. This involves the utilisation of enzymes from various biological systems during the synthesis of chemicals. The use of biocatalysts provides a sustainable alternative to metal catalysts when manufacturing pharmaceuticals and chemicals. Members of the genus Rhodococcus have been found to host many enzymes that can be utilised in biocatalysis due to their highly diverse physiological and metabolic functions. Rhodococcus rhodochrousis able to code for both a nitrilase and a nitrile hydratase which are necessary for the bioconversion of nitriles to carboxylic acids. Here, dimethylformamide successfully induced nitrilases from R. rhodochrous A29, A99 and ATCC BAA-870. These strains were cultured using a benchtop bioreactor. Benzonitrile was used as a substrate for an activity assay where benzoic acid was successfully produced. This was shown by using TLC, FT-IR and NMR spectroscopy. Next, Escherichia coliBL21 (DE3) containing two plasmids encoding a cobalt nitrile hydratase from R. rhodochrous ATCC BAA-870 was cultured in a bioreactor and induced with IPTG. Protein quantification showed an increase in total cellular proteins after induction. Benzamide was successfully produced by using benzonitrile as the substrate during an activity assay indicating successful heterologous expression of a nitrile hydratase. In addition, 100% conversion rate was observed with a minimum of 32 U of enzyme activity for both enzymes. In future, the process whereby these enzymes are produced should be optimised and various substrates should be tested to determine the substrate specificity of nitrile hydrolysing enzymes from these strainsen_ZA
dc.description.librarianCK2021en_ZA
dc.facultyFaculty of Scienceen_ZA
dc.identifier.urihttps://hdl.handle.net/10539/30980
dc.language.isoenen_ZA
dc.schoolSchool of Molecular and Cell Biologyen_ZA
dc.titleProduction of nitrile hydrolysing biocatalysts from Rhodococcus rhodochrousen_ZA
dc.typeThesisen_ZA
Files
Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
SOOBBEN_1129969_MSc Dissertation FInal Submission.pdf
Size:
2.06 MB
Format:
Adobe Portable Document Format
Description:
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
ETD Collection