Biochemical and biophysical studies on SilE from the sil silver resistance locus
Metal ions such as silver (Ag+), mercury (Hg2+), zinc (Zn2+) and copper (Cu+/Cu2+) have a long history of antimicrobial usage and some, such as Cu+/Cu2+, Ag+ and Zn2+ compounds are still used as antimicrobials. Prior to the introduction of antibiotics, Ag+ was arguably the most important antimicrobi...
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| Format: | Thesis (University of Nottingham only) |
| Language: | English |
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2017
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| Online Access: | https://eprints.nottingham.ac.uk/39567/ |
| _version_ | 1848795866248249344 |
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| author | Asiani, Karishma |
| author_facet | Asiani, Karishma |
| author_sort | Asiani, Karishma |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Metal ions such as silver (Ag+), mercury (Hg2+), zinc (Zn2+) and copper (Cu+/Cu2+) have a long history of antimicrobial usage and some, such as Cu+/Cu2+, Ag+ and Zn2+ compounds are still used as antimicrobials. Prior to the introduction of antibiotics, Ag+ was arguably the most important antimicrobial and with the rapid emergence of antibiotic resistance, interest in Ag+ and its compounds as alternative antimicrobials have recently been revived. However, resistance to Ag+-based compounds has been emerging, with initial reports of carriage of silver resistance on a Salmonella enetrica serovar Typhimurium multi-resistance plasmid pMG101 isolated from burns patients in 1975. The proposed model for the mechanism of Ag+ resistance encoded by the sil genes from pMG101 involves export of Ag+ ions via an ATPase (SilP), an RND family effluxer (SilCFBA) and a periplasmic chaperone of Ag+ (SilE).
SilE is a periplasmic protein predicted to be intrinsically disordered until it binds Ag+ ions. This hypothesis was tested using structural and biophysical studies which showed that SilE is an intrinsically disordered and unstructured protein in its free apo-form, but folds to a compact, defined structure upon optimal binding of six Ag+ ions in its holo-form. Sequence analyses and site-directed mutagenesis established the importance of histidine and methionine containing motifs for Ag+-binding, and identified a nucleation core that initiates Ag+-mediated folding of SilE. The data show that SilE is a molecular metal sponge absorbing up to a maximum of eight Ag+ ions. |
| first_indexed | 2025-11-14T19:38:53Z |
| format | Thesis (University of Nottingham only) |
| id | nottingham-39567 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T19:38:53Z |
| publishDate | 2017 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-395672025-02-28T13:38:28Z https://eprints.nottingham.ac.uk/39567/ Biochemical and biophysical studies on SilE from the sil silver resistance locus Asiani, Karishma Metal ions such as silver (Ag+), mercury (Hg2+), zinc (Zn2+) and copper (Cu+/Cu2+) have a long history of antimicrobial usage and some, such as Cu+/Cu2+, Ag+ and Zn2+ compounds are still used as antimicrobials. Prior to the introduction of antibiotics, Ag+ was arguably the most important antimicrobial and with the rapid emergence of antibiotic resistance, interest in Ag+ and its compounds as alternative antimicrobials have recently been revived. However, resistance to Ag+-based compounds has been emerging, with initial reports of carriage of silver resistance on a Salmonella enetrica serovar Typhimurium multi-resistance plasmid pMG101 isolated from burns patients in 1975. The proposed model for the mechanism of Ag+ resistance encoded by the sil genes from pMG101 involves export of Ag+ ions via an ATPase (SilP), an RND family effluxer (SilCFBA) and a periplasmic chaperone of Ag+ (SilE). SilE is a periplasmic protein predicted to be intrinsically disordered until it binds Ag+ ions. This hypothesis was tested using structural and biophysical studies which showed that SilE is an intrinsically disordered and unstructured protein in its free apo-form, but folds to a compact, defined structure upon optimal binding of six Ag+ ions in its holo-form. Sequence analyses and site-directed mutagenesis established the importance of histidine and methionine containing motifs for Ag+-binding, and identified a nucleation core that initiates Ag+-mediated folding of SilE. The data show that SilE is a molecular metal sponge absorbing up to a maximum of eight Ag+ ions. 2017-07-12 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/39567/1/Karishma%20Asiani%20Thesis%20-%20Final.pdf Asiani, Karishma (2017) Biochemical and biophysical studies on SilE from the sil silver resistance locus. PhD thesis, University of Nottingham. |
| spellingShingle | Asiani, Karishma Biochemical and biophysical studies on SilE from the sil silver resistance locus |
| title | Biochemical and biophysical studies on SilE from the sil
silver resistance locus |
| title_full | Biochemical and biophysical studies on SilE from the sil
silver resistance locus |
| title_fullStr | Biochemical and biophysical studies on SilE from the sil
silver resistance locus |
| title_full_unstemmed | Biochemical and biophysical studies on SilE from the sil
silver resistance locus |
| title_short | Biochemical and biophysical studies on SilE from the sil
silver resistance locus |
| title_sort | biochemical and biophysical studies on sile from the sil
silver resistance locus |
| url | https://eprints.nottingham.ac.uk/39567/ |