AbuO, a TolC-like outer membrane protein of Acinetobacter baumannii, is involved in antimicrobial and oxidative stress resistance.

Srinivasan, Vijaya Bharathi and Vaidyanathan, Vasanth and Rajamohan, Govindan (2015) AbuO, a TolC-like outer membrane protein of Acinetobacter baumannii, is involved in antimicrobial and oxidative stress resistance. Antimicrobial agents and chemotherapy, 59 (2). pp. 1236-45. ISSN 1098-6596

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Official URL: http://aac.asm.org/content/59/2/1236.abstract

Abstract

Although Acinetobacter baumannii is well accepted as a nosocomial pathogen, only a few of the outer membrane proteins (OMPs) have been functionally characterized. In this study, we demonstrate the biological functions of AbuO, a homolog of TolC from Escherichia coli. Inactivation of abuO led to increased sensitivity to high osmolarity and oxidative stress challenge. The ΔabuO mutant displayed increased susceptibility to antibiotics, such as amikacin, carbenicillin, ceftriaxone, meropenem, streptomycin, and tigecycline, and hospital-based disinfectants, such as benzalkonium chloride and chlorhexidine. The reverse transcription (RT)-PCR analysis indicated increased expression of efflux pumps (resistance nodulation cell division [RND] efflux pump acrD, 8-fold; SMR-type emrE homolog, 12-fold; and major facilitator superfamily [MFS]-type ampG homolog, 2.7-fold) and two-component response regulators (baeR, 4.67-fold; ompR, 10.43-fold) in the ΔabuO mutant together with downregulation of rstA (4.22-fold) and the pilin chaperone (9-fold). The isogenic mutant displayed lower virulence in a nematode model (P<0.01). Experimental evidence for the binding of MerR-type transcriptional regulator SoxR to radiolabeled abuO promoter suggests regulation of abuO by SoxR in A. baumannii.

Item Type: Article
Additional Information: Copyright © 2015, American Society for Microbiology. All Rights Reserved.
Uncontrolled Keywords: Antimicrobial agents,Outer membrane proteins
Subjects: Q Science > QR Microbiology
Depositing User: Dr. K.P.S.Sengar
Date Deposited: 08 Jul 2015 07:14
Last Modified: 08 Jul 2015 07:14
URI: http://crdd.osdd.net/open/id/eprint/1669

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