Xiaoting Hua1,2, Robert A Moran3, Qingye Xu1,2, Jintao He1,2, Youhong Fang4, Linghong Zhang1,2, Willem van Schaik3, Yunsong Yu1,2. 1. Department of Infectious Diseases, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, China. 2. Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou, China. 3. Institute of Microbiology and Infection, College of Medical and Dental Sciences, The University of Birmingham, Birmingham B15 2TT, UK. 4. Department of Gastroenterology, The Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, 3333 Bin Sheng Road, Hangzhou 310052, Zhejiang Province, China.
Abstract
OBJECTIVES: To reconstruct the evolutionary history of the clinical Acinetobacter baumannii XH1056, which lacks the Oxford scheme allele gdhB. METHODS: Susceptibility testing was performed using broth microdilution and agar dilution. The whole-genome sequence of XH1056 was determined using the Illumina and Oxford Nanopore platforms. MLST was performed using the Pasteur scheme and the Oxford scheme. Antibiotic resistance genes were identified using ABRicate. RESULTS: XH1056 was resistant to all antibiotics tested, apart from colistin, tigecycline and eravacycline. MLST using the Pasteur scheme assigned XH1056 to ST256. However, XH1056 could not be typed with the Oxford MLST scheme as gdhB is not present. Comparative analyses revealed that XH1056 contains a 52 933 bp region acquired from a global clone 2 (GC2) isolate, but is otherwise closely related to the ST23 A. baumannii XH858. The acquired region in XH1056 also contains a 34 932 bp resistance island that resembles AbGRI3 and contains the armA, msrE-mphE, sul1, blaPER-1, aadA1, cmlA1, aadA2, blaCARB-2 and ere(B) resistance genes. Comparison of the XH1056 chromosome to that of GC2 isolate XH859 revealed that the island in XH1056 is in the same chromosomal region as that in XH859. As this island is not in the standard AbGRI3 position, it was named AbGRI5. CONCLUSIONS: XH1056 is a hybrid isolate generated by the acquisition of a chromosomal segment from a GC2 isolate that contains a resistance island in a new location-AbGRI5. As well as generating ST256, it appears likely that a single recombination event is also responsible for the acquisition of AbGRI5 and its associated antibiotic resistance genes.
OBJECTIVES: To reconstruct the evolutionary history of the clinical Acinetobacter baumanniiXH1056, which lacks the Oxford scheme allele gdhB. METHODS: Susceptibility testing was performed using broth microdilution and agar dilution. The whole-genome sequence of XH1056 was determined using the Illumina and Oxford Nanopore platforms. MLST was performed using the Pasteur scheme and the Oxford scheme. Antibiotic resistance genes were identified using ABRicate. RESULTS:XH1056 was resistant to all antibiotics tested, apart from colistin, tigecycline and eravacycline. MLST using the Pasteur scheme assigned XH1056 to ST256. However, XH1056 could not be typed with the Oxford MLST scheme as gdhB is not present. Comparative analyses revealed that XH1056 contains a 52 933 bp region acquired from a global clone 2 (GC2) isolate, but is otherwise closely related to the ST23 A. baumannii XH858. The acquired region in XH1056 also contains a 34 932 bp resistance island that resembles AbGRI3 and contains the armA, msrE-mphE, sul1, blaPER-1, aadA1, cmlA1, aadA2, blaCARB-2 and ere(B) resistance genes. Comparison of the XH1056 chromosome to that of GC2 isolate XH859 revealed that the island in XH1056 is in the same chromosomal region as that in XH859. As this island is not in the standard AbGRI3 position, it was named AbGRI5. CONCLUSIONS:XH1056 is a hybrid isolate generated by the acquisition of a chromosomal segment from a GC2 isolate that contains a resistance island in a new location-AbGRI5. As well as generating ST256, it appears likely that a single recombination event is also responsible for the acquisition of AbGRI5 and its associated antibiotic resistance genes.
Authors: Samira M Hamed; Amira F A Hussein; Mohamed H Al-Agamy; Hesham H Radwan; Mai M Zafer Journal: Front Microbiol Date: 2022-07-22 Impact factor: 6.064
Authors: Valeria Mateo-Estrada; José Luis Fernández-Vázquez; Julia Moreno-Manjón; Ismael L Hernández-González; Eduardo Rodríguez-Noriega; Rayo Morfín-Otero; María Dolores Alcántar-Curiel; Santiago Castillo-Ramírez Journal: mSystems Date: 2021-07-20 Impact factor: 6.496