Sulfur-oxidizing bacteria (SOB) and sulfate-reducingbacteria (SRB) inhabit oilfield productionsystems. Sulfur oxidation driven by SOB and dissimilatory sulfate reduction driven by SRB play important roles in sulfur cycle of oil reservoirs. ...
-Desulfovibrio is a Gram-negative SRB implicated in metal corrosion.30
The stainless steel metal surface of orthodontic brackets can provide
iron atoms that can combine with the sulfide ions created by the
reduction of sulfates to sulfides by SRBs, resulting in the formation of
iron sulfide.31 Produced sulfide acts on the layer of stainless steel, dissolving it into metallic ions taken up by the SRB.32
Geesey et al examined the action of SRB on stainless steel using
electron microscopy and found that the bacterial action can penetrate up
to a depth of 2 to 5 nm.33
Deng et al recently demonstrated that iron sulfide functions as an
excellent electron conductor, playing a role in microbial energy
production.34 Particularly, Desulfovibrio is said to weaken the passive metallic layer on the surface of stainless steel through the dissolution of the ions.34 These ions appear to have a effect on the metabolism of the SRB, enhancing microbiologic corrosion.32
Additionally, the prevalence of SRB in the oral cavity of orthodontic
patients is significant and has wider implications on oral health. The
higher prevalence of SRB is concerning because their metabolic
by-products such as hydrogen sulfide can cause cellular damage,
contributing to the initialisation and propagation of periodontal
disease.13 Particularly, SRB are implicated in oral malodor due to their release of volatile sulfur compounds (VSCs).35 Besides resulting in halitosis, these VSCs may contribute to the aetiology of gingivitis and periodontitis.36
Given its proven potential in causing corrosion and oral pathologic effect,25
the confirmed prevalence of SRB in orthodontic patients raises concern.
Our study found a prevalence of 20% SRB in orthodontic and 2.89% in
non-orthodontic samples examined. Most existing research on the
prevalence of SRB is confined to spheres of periodontal disease and
gastrointestinal diseases.
Zeng L, Luo G, He T, Guo Y, Qian X.J Environ Sci (China). 2016 Aug;46:214-9. doi: 10.1016/j.jes.2016.05.018. Epub 2016 Jun 20.PMID: 27521953
Sediment cores (containing sediment and overlying water)
from Baihua Reservoir (SW China) were cultured under different redox
conditions with different microbial activities, to understand the
effects of sulfate-reducingbacteria (SRB) on mercury (Hg) methylat …
Open Access
Published by De Gruyter Open AccessJanuary 4, 2019 Analysis of physiological parameters of Desulfovibrio strains from individuals with coliti Ivan Kushkevych, Dani Dordević and Peter KollárFrom the journal Open Life Sciences
Abstract: Intestinal
sulfate-reducing bacteria are often isolated from patients with
inflammatory bowel disease, including ulcerative colitis, and can be
involved in the development of gut inflammation. A comparison of the
metabolism of intestinal sulfate-reducing bacteria isolated from
individuals with colitis and healthy controls using statistical analysis
has never been studied and described before. The aim of our research
was to evaluate the parameters of dissimilatory sulfate reduction in Desulfovibrio
species that were isolated from the feces of healthy objects and
individuals with colitis. Principal component analysis indicates that
the strains that were isolated from individuals with colitis grouped in
the same cluster by biomass accumulation and sulfide production, same as
the strains isolated from healthy individuals. Sulfate and lactate
consumption measured over time showed negative correlation (Pearson
correlations, p<0.01), healthy: -0.760; colitis: -0.770; healthy: -0.828; colitis: -0.847, respectively. The calculated linear regression (R2)
was lower in biomass accumulation and hydrogen sulfide production,
0.531; 0.625 respectively. Thus, biomass accumulation and sulfide
production, together with measured kinetic parameters play an important
factor in bowel inflammation, including ulcerative colitis.
Additionally, acetate production can also synergize with H2S, while sulfate consumption and lactate oxidation likely represent minor factors in bowel disease.
The pathogenesis of ulcerative colitis (UC) is known to be significantly influenced by the gut microbiota [1]. A major risk factor for inflammatory bowel disease in
both animals and humans is indicated by increased numbers of
sulfate-reducing bacteria (SRB),and intense dissimilatory sulfate
reduction (DSR) in the gut [2, 3, 4].
While SRB are present in the normal gut microbiota, an increased
frequency of SRB may contribute to colitis development, especially in
association with hydrogen sulfide (H2S)production [5]. Another contributing factor is reduced mucosal thickness in the presence of Desulfovibrio species [6]. Interestingly, SRB have also been associated with rheumatic diseases and ankylosing spondylitis [7].
The production of hydrogen sulfide has been shown to affect the
metabolism of intestinal cells and give rise to various inflammatory
bowel diseases [8]. The presence of SRB may also be responsible for some forms of rectum cancer. The most frequently detected species of SRB are Desulfovibrio
genus in patients with bloody diarrhea, weight loss,anorexia,
epithelial hyperplasia and abscesses (both is animals and humans) [9, 10, 11].
Additionally, in the feces of both humans and animals with ulcerative
colitis, SRB are often detected with increased frequency [8, 12]. The prevalence of ulcerative colitis (UC) in Western
countries is observed at a rate of 12 per 100,000 people, mostly between
the ages of 15 and 30 years old [13]. Certainly, the location and severity of UC is influenced by medication and dosage in treatment [4, 8, 14, 15].The
final product of SRB is hydrogen sulfide, which is toxic, and in
addition to contributing to IBD development (including UC and Crohn’s
disease), it is also associated with a higher risk for neurodegenerative
illness, likely through DNA damage and mutation, enzyme inhibition and
mitochondrial respiration inhibition [16, 17, 18, 19, 20, 21]. The
novelty of our study lies in the fact that the comparison of
dissimilatory sulfate reduction (DSR), including sulfate and lactate
consumption, the production of hydrogen sulfide and acetate, as well as
growth parameters of the SRB strains isolated from healthy and
individuals with UC has never been presented before. The aim of our
research was to evaluate the parameters of growth (biomass) of Desulfovibrio
species that were isolated from the feces of individuals with colitis
and healthy controls, as well as to investigate changes in dissimilatory
sulfate reduction of these bacterial strains.
,
Dani Dordević
and
Peter KollárFrom the journal Open Life Sciences
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