Biology Reference
In-Depth Information
1. OVERVIEW
In 1913, McFadyean and Stockman isolated a
Vibrio
-like organism
from aborted ovine foetuses. After the creation of the genus
Campylobacter
in 1963 (
Butzler, 2004; Skirrow, 2006
),
V´ron and Chateline (1973)
reported four species within the genus
Campylobacter
:
C. fetus
,
C. coli
,
C. jejuni
and
C. sputorum
. Currently, the
Campylobacteraceae
family comprises
at least 15 species of
Campylobacter
(
Debruine, Gevers, & Vandamme, 2008
)
being found in a range of niches, from free-living environmental organisms
to commensals or parasites in humans and domestic animals.
Campylobacter
has been recognised as one of the main causes of bacterial
gastroenteritis in the developed world (
Friedman, Neimann, Wegener, &
Tauxe, 2000; Scallan et al., 2011; Simonsen et al., 2011
). It is estimated that
9.4 million episodes of foodborne illness arise every year in the United
States; 9% of those cases and 15% of the related hospitalisations are caused
by
Campylobacter
species (
Scallan et al., 2011
).
C. jejuni
is a commensal in the lower intestine of chickens but a pathogen
in humans. Contamination of poultry products during processing constitutes
an important route of transmission (
Friedman et al., 2000
).
C. jejuni
infection produces an inflammatory response (
Bakhiet et al., 2004; Jacobs
et al., 1998; Koga et al., 2005; Zheng, Meng, Zhao, Singh, & Song,
2008
) associated with pathological symptoms. Even though the majority
of the symptoms related to
Campylobacteriosis
are self-limited and infection
is generally restricted to the intestine, invasion of other tissues, mainly in
immunocompromised and elderly patients, leads to significant morbidity
and mortality (
Allos, 2001; Wassenaar &Blaser, 1999
). Moreover, the devel-
opment of autoimmune diseases such as Guillain-Barr
´
syndrome andMiller
Fisher syndrome, that mainly occur as sequelae of gastrointestinal infection
(
Fisher, 1956; Tam et al., 2007
), has been closely related to a preceding
infection by
C. jejuni
.
During infection and pathogenesis,
C. jejuni
is exposed to nitric oxide
(NO) and a range of other reactive nitrogen species (RNS) (see
Sections 2
and 4.3
). The ability of the bacterium to detoxify these compounds has been
mainly associated with the expression of two haemoglobins (Cgb and Ctb) in
response to nitrosative stress.
The most recent bioinformatics survey of sequences such as globins in
over 2200 bacterial genomes has provided a complete inventory of globins
present in this kingdom (
Vinogradov, Tinajero-Trejo, Poole, &Hoogewijs,
2013
). This study revealed genes encoding globins in half of the bacterial
