New applications of Peroxidases in Biotechnology and Nanotechnology

Abstract

Biocatalysis can offer advantages over traditional chemical synthesis, offering chemical orthogonality. The size range of biocatalysts makes them particularly suitable in nanotechnology applications, however their potential is yet to be fully explored.One of the key requirements in the development of nanotechnological devices is the need to generate nanometre-sized features on a variety of surfaces. However, current methods of nanofabrication largely rely on methods derived from the microelectronics sector, which are energetically intensive, costly and are extremely limited in the chemical complexity they can achieve. The work presented here includes development of a new wide area method of synthesising nanometre-sized features by constructive deposition of material. Biocatalytic nanolithography combines the control of polymerising biocatalyst and the precision of scanning probe microscopy. In this work horseradish peroxidase has been immobilised to probe arrays and was used for the in situ generation and deposition of aryl amine polymers. Lithography was carried out with nanometre resolution and on a wide area for the first time.Additionally, research was carried out utilising peroxidase for the synthesis of fine chemicals. Specifically, their ability to catalyse the formation of quinoid systems, which often require harsh chemical conditions to generation. Quinoid systems can be used as reactive intermediates of the syntheses of organic backbones. Horseradish peroxidase was used to catalyse the formation of o-quinone methide, o-quinone imine and o-quinone systems. Novel tandem one-pot cycloadditions with dienophiles were carried out with o-quinone methide and o-quinone imine systems to form fused ring aromatics, on a synthetically relevant scale. Tandem 'one-pot' Michael additions with aryl amines were carried out on o-quinone systems. The adducts formed with non/halogenated aryl amines had significantly different UV/Vis spectrum and could be used to assay halogenation by this difference. It was shown this detection could be coupled with a flavin dependent halogenase which currently lack a high throughput assay, in a 'one-pot' workflow.

Date of Award	1 Aug 2017
Original language	English
Awarding Institution	The University of Manchester
Supervisor	Jason Micklefield (Supervisor) & Lu Shin Wong (Supervisor)