title: A hypervariable genomic island identified in clinical and environmental Mycobacterium avium subsp. hominissuis isolates from Germany.
abstract: Mycobacterium avium subsp. hominissuis (MAH) is an opportunistic human pathogen widespread in the environment. Genomic islands (GI)s represent a part of the accessory genome of bacteria and influence virulence, drug-resistance or fitness and trigger bacterial evolution. We previously identified a novel GI in four MAH genomes. Here, we further explored this GI in a larger collection of MAH isolates from Germany (n=41), including 20 clinical and 21 environmental isolates. Based on comparative whole genome analysis, we detected this GI in 39/41 (95.1%) isolates. Although all these GIs integrated in the same insertion hotspot, there is high variability in the genetic structure of this GI: eight different types of GI have been identified, designated A-H (sized 6.2-73.3kb). These GIs were arranged as single GI (23/41, 56.1%), combination of two different GIs (14/41, 34.1%) or combination of three different GIs (2/41, 4.9%) in the insertion hotspot. Moreover, two GI types shared more than 80% sequence identity with sequences of M. canettii, responsible for Tuberculosis. A total of 253 different genes were identified in all GIs, among which the previously documented virulence-related genes mmpL10 and mce. The diversity of the GI and the sequence similarity with other mycobacteria suggests cross-species transfer, involving also highly pathogenic species. Shuffling of potential virulence genes such as mmpL10 via this GI may create new pathogens that can cause future outbreaks.
authors.affiliation: Robert Koch Institute, Berlin, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Sanchini
authors.affiliation: Robert Koch Institute, Berlin, Germany.
authors.forename: Torsten
authors.initials: T
authors.lastname: Semmler
authors.affiliation: Robert Koch Institute, Berlin, Germany.
authors.forename: Lei
authors.initials: L
authors.lastname: Mao
authors.affiliation: University of Hyderabad, Gachibowli, India.
authors.forename: Narender
authors.initials: N
authors.lastname: Kumar
authors.affiliation: Freie Universitaet Berlin, Germany.
authors.forename: Flavia
authors.initials: F
authors.lastname: Dematheis
authors.affiliation: University of Hyderabad, Gachibowli, India.
authors.forename: Kshitij
authors.initials: K
authors.lastname: Tandon
authors.affiliation: University of Hyderabad, Gachibowli, India.
authors.forename: Vidyullatha
authors.initials: V
authors.lastname: Peddireddy
authors.affiliation: University of Hyderabad, Gachibowli, India.
authors.forename: Niyaz
authors.initials: N
authors.lastname: Ahmed
authors.affiliation: Robert Koch Institute, Berlin, Germany. Electronic address: LewinA@rki.de.
authors.forename: Astrid
authors.initials: A
authors.lastname: Lewin
mesh_terms: D000328:Adult; D002648:Child; D002675:Child, Preschool; D004783:Environmental Microbiology; D022761:Gene Transfer, Horizontal; D005798:Genes, Bacterial; D014644:Genetic Variation; D016680:Genome, Bacterial; D044404:Genomic Islands; D005838:Genotype; D005858:Germany; D006801:Humans; D009162:Mycobacterium avium / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid; D014376:Tuberculosis / Q000382:microbiology*
keywords: COG; Clusters of Orthologous Groups; GI; Genomic island; MAH; MCE; MmpL; Mycobacterium avium; Mycobacterium avium subsp. hominissuis; NTM; antibiotic-resistance; genomic islands; horizontal gene transfer; mammalian cell entry; mmpL; mycobacterial membrane protein large; non-tuberculous mycobacteria