P63
Preliminary Results on the Whole genome-based characterization and phylogenetics of Mycobacterium africanum in Nigeria and comparison with a L5-L6 database
M R Sahal(1,2) K La(2,3) G Senelle(4) T W Panda(5) D W Taura(6) G Refrégier(1,7) C Guyeux(4) E Cambau(2,3) C Sola(1,2)
1:Université Paris-Saclay; 2:Inserm UMR 1137; 3:AP-HP, GHU Nord site Bichat, Service de mycobactériologie spécialisée et de référence, Paris, France; 4:FEMTO-ST Institute, UMR 6174 CNRS, DISC Computer Science Department, Université Bourgogne Franche-Comté (UBFC), Besançon; 5:Department of Microbiology and Parasitology, Aminu Kano Teaching Hospital Kano, Nigeria; 6:Department of Microbiology, Faculty of Science, Bayero University Kano, Nigeria; 7:Ecologie Systematique Evolution, Université Paris-Saclay, CNRS, AgroParisTech, UMR ESE, 91405, Orsay, France
Mycobacterium africanum (MAF) lineage L5 and L6 are not observed in humans others than whose originating from West Africa. The purpose of this study was to increase our knowledge on taxonomy of Mycobacterium africanum lineages. The study included 325 MTBC isolates from Nigeria out of which 13 were identified as belonging to MAF using a MIRU-24 assay, and confirmed by Hain-MTBC® line-probe assay. In addition, 12 MAF isolates from patients from Lariboisière and Saint Louis Hospitals were included. These 25 MAF isolates were sequenced using Illumina WGS technology. Computational analysis was done using the “TB-Annotator” platform that provides new sublineages (Senelle et al, unpublished results). Out of 25 isolates, 11 were confirmed as L5, 10 as L6, and 4 were reassigned to L4. Nigerian L5 isolates belong to L5.1 and 5.2 and none to 5.3. Four isolates distant by a mean of 320 SNPs (SD=95) belong to a sublineage coined by Senelle et al “L5.1.1.2.1”. This suggests that “L5.1.1.2.1” sublineage is relatively ancient. Inside L6, we found isolates from all sublineages of L6.1 and L6.2 in France but not in Nigeria. The single Nigerian L6 isolate from our sample belong to the L6.3.1 sublineage. Another interesting output of “TB-Annotator” is the fact that all L5 isolates miss 62 genes present in H37Rv, and L6 miss 64 genes. Our study shows that Nigeria presents a large diversity of MAF, and that “TB-Annotator” is a useful platform to go deeper into L5 and L6 classification.