Identification and characterization of a carnitine transporter in Acinetobacter baumannii

  • The opportunistic pathogen Acinetobacter baumannii is able to grow on carnitine. The genes encoding the pathway for carnitine degradation to the intermediate malic acid are known but the transporter mediating carnitine uptake remained to be identified. The open reading frame HMPREF0010_01347 (aci01347) of Acinetobacter baumannii is annotated as a gene encoding a potential transporter of the betaine/choline/carnitine transporter (BCCT) family. To study the physiological function of Aci01347, the gene was deleted from A. baumannii ATCC 19606. The mutant was no longer able to grow on carnitine as sole carbon and energy source demonstrating the importance of this transporter for carnitine metabolism. Aci01347 was produced in Escherichia coli MKH13, a strain devoid of any compatible solute transporter, and the recombinant E. coli MKH13 strain was found to take up carnitine in an energy‐dependent fashion. Aci01347 also transported choline, a compound known to be accumulated under osmotic stress. Choline transport was osmolarity‐independent which is consistent with the absence of an extended C‐terminus found in osmo‐activated BCCT. We propose that the Aci01347 is the carnitine transporter mediating the first step in the growth of A. baumannii on carnitine.
Author:Jennifer Breisch, Izabela Jadwiga Waclawska-Krzeminski, Beate AverhoffORCiD
Pubmed Id:
Parent Title (English):MicrobiologyOpen
Place of publication:Malden, Mass.
Document Type:Article
Year of Completion:2018
Date of first Publication:2018/10/14
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2018/10/18
Tag:Acinetobacter baumannii; betaine/choline/carnitine transporter; carnitine metabolism; human host adaptation; human pathogen
Page Number:8
First Page:1
Last Page:8
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Institutes:Biowissenschaften / Biowissenschaften
Dewey Decimal Classification:5 Naturwissenschaften und Mathematik / 57 Biowissenschaften; Biologie / 570 Biowissenschaften; Biologie
Licence (German):License LogoCreative Commons - Namensnennung 4.0