Characterisation of mcr-4.3 in a colistin-resistant Acinetobacter nosocomialis clinical isolate from Cape Town, South Africa
| dc.contributor.author | Snyman, Yolandi | en_ZA |
| dc.contributor.author | Reuter, Sandra | en_ZA |
| dc.contributor.author | Whitelaw, Andrew Christopher | en_ZA |
| dc.contributor.author | Stein, Lisa | en_ZA |
| dc.contributor.author | Maloba, Motlatji Reratilwe Bonnie | en_ZA |
| dc.contributor.author | Newton-Foot, Mae | en_ZA |
| dc.date.accessioned | 2021-08-19T10:35:18Z | |
| dc.date.available | 2021-08-19T10:35:18Z | |
| dc.date.issued | 2021 | |
| dc.description | CITATION: Snyman, Y., et al. 2021. Characterisation of mcr-4.3 in a colistin-resistant Acinetobacter nosocomialis clinical isolate from Cape Town, South Africa. Journal of Global Antimicrobial Resistance, 25:102-106, doi:10.1016/j.jgar.2021.03.002. | |
| dc.description | The original publication is available at https://www.sciencedirect.com | |
| dc.description | Publication of this article was funded by the Stellenbosch University Open Access Fund | |
| dc.description.abstract | Objectives: Colistin resistance in Acinetobacter spp. is increasing, resulting in potentially untreatable noso- comial infections. Plasmid-mediated colistin resistance is of particular concern due to its low fitness cost and potential transferability to other bacterial strains and species. This study investigated the colistin resistance mechanism in a clinical Acinetobacter nosocomialis isolate from Cape Town, South Africa. Methods: A colistin-resistant A. nosocomialis isolate was identified from a blood culture in 2017. PCR and Illumina whole-genome sequencing (WGS) were performed to identify genes and mutations conferring resistance to colistin. Plasmid sequencing was performed on an Oxford Nanopore platform. mcr function- ality was assessed by broth microdilution after cloning the mcr gene into pET-48b( + ) and expressing it in SHuffle®T7 Escherichia coli and after curing the plasmid using 62.5 mg/L acridine orange. Results: The colistin minimum inhibitory concentration (MIC) of the A. nosocomialis isolate was 16 mg/L. The mcr-4.3 gene was detected by PCR and WGS. No other previously described colistin resistance mech- anism was found by WGS. The mcr-4.3 gene was identified on a 24 024-bp RepB plasmid (pCAC13a). Functionality studies showed that recombinant mcr-4.3 did not confer colistin resistance in E. coli. How- ever, plasmid curing of pCAC13a restored colistin susceptibility in A. nosocomialis . Conclusion: We describe the first detection of a plasmid-mediated mcr-4.3 gene encoding colistin re- sistance in A. nosocomialis and the first detection of mcr-4.3 in a clinical isolate in Africa. Recombinant expression of mcr-4.3 did not confer colistin resistance in E. coli , suggesting that its functionality may be RepB plasmid-dependent or species-specific. | en_ZA |
| dc.description.uri | https://www.sciencedirect.com/science/article/pii/S2213716521000679 | |
| dc.description.version | Publisher's version | |
| dc.format.extent | 5 pages | en_ZA |
| dc.identifier.citation | Snyman, Y., et al. 2021. Characterisation of mcr-4.3 in a colistin-resistant Acinetobacter nosocomialis clinical isolate from Cape Town, South Africa. Journal of Global Antimicrobial Resistance, 25:102-106, doi:10.1016/j.jgar.2021.03.002 | |
| dc.identifier.issn | 2213-7165 (online) | |
| dc.identifier.other | doi:10.1016/j.jgar.2021.03.002 | |
| dc.identifier.uri | http://hdl.handle.net/10019.1/110889 | |
| dc.language.iso | en_ZA | en_ZA |
| dc.publisher | Elsevier | en_ZA |
| dc.rights.holder | Authors retain copyright | en_ZA |
| dc.subject | Polymyxin resistance | en_ZA |
| dc.subject | Acinetobacter | en_ZA |
| dc.subject | Nosocomial infections | en_ZA |
| dc.subject | Drug resistance | en_ZA |
| dc.subject | Colistin | en_ZA |
| dc.title | Characterisation of mcr-4.3 in a colistin-resistant Acinetobacter nosocomialis clinical isolate from Cape Town, South Africa | en_ZA |
| dc.type | Article | en_ZA |