Abstract
There is an ongoing debate about the clinical significance of
Sphingomonas paucimobilis
as a virulent bacterial pathogen. In the present study, we investigated the presence of different virulence factors and genes in
Sphingomonas
bacteria. We utilized phylogenetic, comparative genomics and bioinformatics analysis to investigate the potentiality of
Sphingomonas
bacteria as virulent pathogenic bacteria. The 16S ribosomal RNA gene (16S rDNA) phylogenetic tree showed that the closest bacterial taxon to
Sphingomonas
is
Brucella
with a bootstrap value of 87 followed by
Helicobacter
,
Campylobacter
,
Pseudomonas
, and then
Legionella. Sphingomonas
shared no virulence factors with
Helicobacter
or
Campylobacter
, despite their close phylogenic relationship. In spite of the phylogenetic divergence between
Sphingomonas
and
Pseudomonas
, they shared many major virulence factors, such as adherence, antiphagocytosis, iron uptake, proteases, and quorum sensing. In conclusion,
Sphingomonas
spp. contains several major virulence factors resembling
Pseudomonas
sp.,
Legionella
sp.,
Brucella
sp., and
Bordetella
sp. virulence factors. Similarity of virulence factors did not match phylogenetic relationships. These findings suggest horizontal gene transfer of virulence factors rather than sharing a common pathogenic ancestor.
Sphingomonas
spp. is potential virulent bacterial pathogen.