{"id":{"repo_id":"western-cape","oai_identifier":"oai:uwcscholar.uwc.ac.za:10566/20562"},"canonical_url":"https://search.dev.ndltd.org/etd/western-cape/oai:uwcscholar.uwc.ac.za:10566/20562","repository":{"repo_id":"western-cape","name":"University of the Western Cape","base_url":"https://uwcscholar.uwc.ac.za:8443/server/oai/request"},"display":{"title":"Screening for novel cold-adapted nitrile hydratases in Antarctic metagenornic libraries","abstract":"Nitrile hydratases (NHase) catalyse the hydrolysis of nitriles to their corresponding amides, the first step in the nitrile degradation pathway. The second step is the conversion of the amide to a carboxylic acid, catalysed by an amidase. The NHases published to date have been isolated from mesophilic and thermophilic bacteria. The aim of this study was to identify a novel cold-adapted NHase from psychrophilic and psychrotrophic bacteria. The identification of a cold-adapted NHase is of interest for its potential use in chemical and pharmaceutical production. Enzymes isolated from psychrophilic bacteria typically have a high specific activ ity and low thermal stabi lity to cope with the inhibition of chemical reactions caused by low temperatures. However, culture based screening for these activities tend to reisolate already characterised isolates amiable to culturing. To access the majority of the bacterial biodiversity that the uncultured bacteria represent, the metagenomic approach was used to screen for nitrile degrading activity. Metage-nomic libraries constructed from soil taken from the McMurdo Dry Valleys in Antarctica were used for both functional and sequence based screens of NHases. Functional screens that were trialled were based on pH change and oligotrophic selective growth.","abstract_html":"Nitrile hydratases (NHase) catalyse the hydrolysis of nitriles to their corresponding amides, the first step in the nitrile degradation pathway. The second step is the conversion of the amide to a carboxylic acid, catalysed by an amidase. The NHases published to date have been isolated from mesophilic and thermophilic bacteria. The aim of this study was to identify a novel cold-adapted NHase from psychrophilic and psychrotrophic bacteria. The identification of a cold-adapted NHase is of interest for its potential use in chemical and pharmaceutical production. Enzymes isolated from psychrophilic bacteria typically have a high specific activ ity and low thermal stabi lity to cope with the inhibition of chemical reactions caused by low temperatures. However, culture based screening for these activities tend to reisolate already characterised isolates amiable to culturing. To access the majority of the bacterial biodiversity that the uncultured bacteria represent, the metagenomic approach was used to screen for nitrile degrading activity. Metage-nomic libraries constructed from soil taken from the McMurdo Dry Valleys in Antarctica were used for both functional and sequence based screens of NHases. Functional screens that were trialled were based on pH change and oligotrophic selective growth.","abstract_has_math":false,"creators":["Williams, Wesley Trevor"],"institution":"University of the Western Cape","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Cowan Don"],"committee_chairs":[],"committee_members":[],"year":2024,"date_issued":"2024","date_published":"2024","updated_at":"2026-07-24T06:00:44Z","subjects":["Metagenomics","Antarctic dry valley","Nitrile hydratase","Psychrotrophic","Rhodococcus erythropolis"],"languages":[],"rights":[],"rights_urls":["https://uwcscholar.uwc.ac.za/bitstreams/c7457511-ed92-43f8-8f07-e507782aabaf/download"],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Cowan Don"]},{"key":"dc:creator","label":"Author","values":["Williams, Wesley Trevor"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2024"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of the Western Cape"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://hdl.handle.net/10566/20562"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Metagenomics","Antarctic dry valley","Nitrile hydratase","Psychrotrophic","Rhodococcus erythropolis"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["https://uwcscholar.uwc.ac.za/bitstreams/c7457511-ed92-43f8-8f07-e507782aabaf/download"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://uwcscholar.uwc.ac.za/bitstreams/9b6f295a-f38d-4ec4-91b7-53fec90eff41/download"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Nitrile hydratases (NHase) catalyse the hydrolysis of nitriles to their corresponding amides, the first step in the nitrile degradation pathway. The second step is the conversion of the amide to a carboxylic acid, catalysed by an amidase. The NHases published to date have been isolated from mesophilic and thermophilic bacteria. The aim of this study was to identify a novel cold-adapted NHase from psychrophilic and psychrotrophic bacteria. The identification of a cold-adapted NHase is of interest for its potential use in chemical and pharmaceutical production. Enzymes isolated from psychrophilic bacteria typically have a high specific activ ity and low thermal stabi lity to cope with the inhibition of chemical reactions caused by low temperatures. However, culture based screening for these activities tend to reisolate already characterised isolates amiable to culturing. To access the majority of the bacterial biodiversity that the uncultured bacteria represent, the metagenomic approach was used to screen for nitrile degrading activity. Metage-nomic libraries constructed from soil taken from the McMurdo Dry Valleys in Antarctica were used for both functional and sequence based screens of NHases. Functional screens that were trialled were based on pH change and oligotrophic selective growth."]},{"key":"dc:format.checksum.md5","label":"Dc Format Checksum Md5","values":["f22e2d802563eaf8d016a018cb8d08ce","bb9bdc0b3349e4284e09149f943790b4","4035e954950475e7b229c72283905d5c"]},{"key":"dc:title","label":"Title","values":["Screening for novel cold-adapted nitrile hydratases in Antarctic metagenornic libraries"]}]}],"canonical_facts":{"dc:contributor.advisor":["Cowan Don"],"dc:creator":["Williams, Wesley Trevor"],"dc:date.issued":["2024"],"dc:description.abstract":["Nitrile hydratases (NHase) catalyse the hydrolysis of nitriles to their corresponding amides, the first step in the nitrile degradation pathway. The second step is the conversion of the amide to a carboxylic acid, catalysed by an amidase. The NHases published to date have been isolated from mesophilic and thermophilic bacteria. The aim of this study was to identify a novel cold-adapted NHase from psychrophilic and psychrotrophic bacteria. The identification of a cold-adapted NHase is of interest for its potential use in chemical and pharmaceutical production. Enzymes isolated from psychrophilic bacteria typically have a high specific activ ity and low thermal stabi lity to cope with the inhibition of chemical reactions caused by low temperatures. However, culture based screening for these activities tend to reisolate already characterised isolates amiable to culturing. To access the majority of the bacterial biodiversity that the uncultured bacteria represent, the metagenomic approach was used to screen for nitrile degrading activity. Metage-nomic libraries constructed from soil taken from the McMurdo Dry Valleys in Antarctica were used for both functional and sequence based screens of NHases. Functional screens that were trialled were based on pH change and oligotrophic selective growth."],"dc:format.checksum.md5":["f22e2d802563eaf8d016a018cb8d08ce","bb9bdc0b3349e4284e09149f943790b4","4035e954950475e7b229c72283905d5c"],"dc:identifier.uri":["https://uwcscholar.uwc.ac.za/bitstreams/9b6f295a-f38d-4ec4-91b7-53fec90eff41/download"],"dc:publisher.institution":["University of the Western Cape"],"dc:relation.isreferencedby":["https://hdl.handle.net/10566/20562"],"dc:rights":["https://uwcscholar.uwc.ac.za/bitstreams/c7457511-ed92-43f8-8f07-e507782aabaf/download"],"dc:subject":["Metagenomics","Antarctic dry valley","Nitrile hydratase","Psychrotrophic","Rhodococcus erythropolis"],"dc:title":["Screening for novel cold-adapted nitrile hydratases in Antarctic metagenornic libraries"],"dc:type":["Thesis"]},"updated_at":"2026-07-24T06:00:44Z"}