G C A T T A C G G C A T genes Article Unintentional Genomic Changes Endow Cupriavidus metallidurans with an Augmented Heavy-Metal Resistance Felipe A. Millacura 1, Paul J. Janssen 2, Pieter Monsieurs 2, Ann Janssen 2, Ann Provoost 2, Rob Van Houdt 2 and Luis A. Rojas 3,* 1 School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JQ, UK;
[email protected] 2 Interdisciplinary Biosciences, Belgian Nuclear Research Centre, SCK•CEN, 2400 Mol, Belgium;
[email protected] (P.J.J.);
[email protected] (P.M.);
[email protected] (A.J);
[email protected] (A.P.);
[email protected] (R.V.H.) 3 Chemistry Department, Faculty of Sciences, Universidad Católica del Norte, UCN, Antofagasta 1240000, Chile * Correspondence:
[email protected]; Tel.: +56-55-235-5629 Received: 6 October 2018; Accepted: 8 November 2018; Published: 13 November 2018 Abstract: For the past three decades, Cupriavidus metallidurans has been one of the major model organisms for bacterial tolerance to heavy metals. Its type strain CH34 contains at least 24 gene clusters distributed over four replicons, allowing for intricate and multilayered metal responses. To gain organic mercury resistance in CH34, broad-spectrum mer genes were introduced in a previous work via conjugation of the IncP-1β plasmid pTP6. However, we recently noted that this CH34-derived strain, MSR33, unexpectedly showed an increased resistance to other metals (i.e., Co2+, Ni2+, and Cd2+). To thoroughly investigate this phenomenon, we resequenced the entire genome of MSR33 and compared its DNA sequence and basal gene expression profile to those of its parental strain CH34.