Author/Authors :
Vijayakumar, Saranya Christian Medical College, Vellore, India , Wattal, Chand Sir Ganga Ram Hospital, New Delhi, India , J.K, Oberoi Sir Ganga Ram Hospital, New Delhi, India , Bhattacharya, Sanjay Tata Medical Center, Kolkata, India , Vasudevan, Karthick Christian Medical College, Vellore, India , Anandan, Shalini Christian Medical College, Vellore, India , Walia, Kamini Indian Council of Medical Research, New Delhi, India , Veeraraghavan, Balaji Christian Medical College, Vellore, India
Abstract :
Carbapenem resistance in Acinetobacter baumannii is due to bla OXA-23, which is endemic in India. Recently, the sporadic presence of bla OXA-58 as well as the occurrence of dual carbapenemases were observed. The mobility as well as the dissemination of these resistance genes were mainly mediated by various mobile genetic elements. The present study was aimed at characterizing the genetic arrangement of bla OXA-23, bla NDM-1 and bla OXA-58 identified in two complete genomes of carbapenem-resistant A. baumannii (CRAB). Complete genomes obtained using a hybrid-assembly approach revealed the accurate arrangement of Tn2006 with bla OXA-23, ISAba125 with bla NDM and ISAba3 with bla OXA-58. In addition, the association of IntI1 integrase with the bla CARB-2 gene and several virulence factors required for type-IV pili assembly, motility and biofilm formation have been identified. The current study provided deeper insight into the complete characterization of insertion sequences and transposons associated with the carbapenem-resistant genes using short reads of IonTorrent PGM and long reads of MinIon in A. baumannii .
