Complete Genome Arrangement Revealed the Emergence of a Poultry Origin Superbug Citrobacter portucalensis Strain NR-12.
J Glob Antimicrob Resist. 2019 Jun 08;:
Authors: Hasan S, Sultana M, Hossain MA
OBJECTIVES: Citrobacter spp. are part of normal human and animal intestinal flora. Citrobacter portucalensis is closely related to C. freundii which is an emerging opportunistic nosocomial pathogen. The aim of the study was to retrieve colistin resistant Citrobacter spp. from poultry of Bangladesh.
METHODS: C. portucalensis strain NR-12 was isolated from poultry droppings and subjected to antibiotic susceptibility test. Complete genome analysis of NR-12 was done followed by bioinformatics. To our knowledge, this is one of first reports of its kind of complete genome sequence of MDR C. portucalensis isolated from veterinary samples.
RESULTS: C. portucalensis strain NR-12 showed resistance to polymyxin, sulfonamide, tetracycline, fluoroquinolone and macrolide. Its complete genome revealed 13 acquired antimicrobial resistance gene markers (AMRs) conferring resistance to 8 different antibiotic groups, such as dfrA12 (trimethoprim); sul1 and sul2 (sulfonamide), mph (A) (macrolide); tet (A) (tetracycline); qnrS1 and qnrB13 (fluoroquinolone), blaCMY-39 (extended-spectrum β-lactamase (ESBL)), a blaTEM-176 (non-ESBL) and aadA2, aph (3')-Ia, aph (3'')-Ib, aph (3')-Ic, aph (3')-Id, strA, strB) (aminoglycoside). The genome possessed a class 1 integron (IntI1) gene cassette harboring 4 different antibiotic resistance genes (dfrA12, aadA2, sul1, mph (A)). The organization of class 1 integron (IntI1) carrying MDR determinants in C. portucalensis strain NR-12 is also first reported here. Colistin resistant genes such as mgrB, phoP, phoQ, pmrA, pmrB, eptB and arnB were also present within NR-12.
CONCLUSION: C. portucalensis NR-12 was resistant to 7 different antibiotics from 5 antimicrobial groups. Understanding of its resistant mechanism is necessary to implicate control strategy.
PMID: 31185330 [PubMed - as supplied by publisher]