Iyamu, E and Ekhaise, F. O
Abstract
Purpose: Molecular phylogenetic analyses have proven beneficial in overcoming some limitations of traditional phenotypic procedures for the detection and characterisation of bacterial isolates. This study aimed to identify bacterial isolates from hydrogel (soft) contact lenses worn by selected students of the University of Benin, Nigeria, using 16S rRNA gene analysis.
Methods: Eleven bacterial isolates from worn hydrogel lenses, which remained unidentified using traditional phenotypic techniques, were transferred to the molecular biology section of the Labour Medical and Research Laboratory for possible identification by phylogenetic analysis, to encompass a full range of bacteria considered as normal flora of the eyes. Bacterial genomic DNA was extracted with the ZymoBIOMICS DNA Mini Kit (Zymo Research Corp., Irvin, CA, USA), amplified with polymerase chain reaction (PCR), and the amplicons were sequenced with the ABI3500xL Genetic Analyser (Applied Biosystems, Foster City, CA, USA). The nucleotide sequences were assembled and deposited in the GenBank database for alignment with the prototype strains.
Results: The bacterial isolates identified were Burkholderiacenocepacia GIMC 4560: BCN122, Cupriavidus pauculus KPS 201, and Comamonas testosteroni M.pstv. 4.2, Acinetobacter calcoaceticus NBRC 13006, Achromobacter denitrificans SW2, Bacillus cereus FORC_048, Staphylococcus saprophyticus Marseille-P541, Burkholderia cenocepacia GIMC 4560: Bcn122, Acinetobacter calcoaceticus 7.3, and Comamonas sp. 6.1 and Acinetobacter sp. pp2a.
Conclusion: The 16S rRNA gene sequence analysis identified 82% of the isolates at the strain level and 18% at the genus level.
Keywords: 16S rRNA gene sequence, contact lens bacterial isolates, hydrogel contact lenses, phenotypic methods, phylogenetic analysis, polymerase chain reaction.