Citrobacter rodentium of mice and man
The major classes of enterobacteria harbour a conserved core genomic structure, common to both commensal and pathogenic strains, that’s presumably optimized to a life style involving colonization of the host intestine and transmission via the environment. In pathogenic bacteria this core genome framework is decorated with novel genetic islands that are often related to adaptive phenotypes like virulence. This classical genome organization is well illustrated by a gaggle of extracellular enteric pathogens, which incorporates enteropathogenic Escherichia coli (EPEC), enterohaemorrhagic E. coli (EHEC) and Citrobacter rodentium, all of which use attaching and effacing (A/E) lesion formation as a serious mechanism of tissue targeting and infection. [1]
Cadmium Accumulation by a Citrobacter sp.
Cadmium accumulation by a Citrobacter sp. growing within the presence of the metal occurred as a pointy peak during the mid-exponential phase of growth, but cultures showed considerable inhibition of growth compared to cadmium-free controls. This problem was overcome by pregrowing the cells in cadmium-free medium and subsequently exposing them to the metal within the resting state, under which conditions higher concentrations of cadmium were tolerated and metal uptake was enhanced. This ability was retained when the cells were immobilized then challenged with a flow containing Cd2+; 65% of the metal presented was faraway from solution. The influence on uptake of the composition of the exposure buffer and of varied cell treatments were investigated and therefore the results are discussed with reference to the anticipated speciation of the cadmium presented to the cells and also with reference to the probable mechanism of metal uptake. this is often thought to occur through the activity of a cell-bound phosphatase, induced during pre-growth by the supply of glycerol 2-phosphate as sole phosphorus source. Continued enzyme function in resting cells would then precipitate the metal as cell-bound cadmium phosphate. [2]
Decolorization of triphenylmethane and azo dyes by Citrobacter sp.
A Citrobacter sp., isolated from soil at an effluent treatment plant of a textile and dyeing industry, decolorized several recalcitrant dyes except bromphenol blue . quite 90% of gentian violet and Methyl Red at 100 μM were reduced within 1 h. crystal violet , Malachite Green and Brilliant Green lost over 80% of their colors within the same condition, but the share decolorization of Basic Fuchsin and azo dye were but the others, 66 and 26%, respectively. Decolorization of azo dye was mainly thanks to adsorption to cells. Color removal was optimal at pH 7–9 and 35–40 °C. Decolorization of dyes was also observed with extracellular culture filtrate, indicating the colour removal by enzymatic biodegradation. [3]
Citrobacter freundii fitness during bloodstream infection
Sepsis resulting from microbial colonization of the bloodstream may be a serious health concern related to high mortality rates. the target of this study was to define the physiologic requirements of Citrobacter freundii within the bloodstream as a model for bacteremia caused by opportunistic Gram-negative pathogens. A genetic screen during a murine host identified 177 genes that contributed significantly to fitness, the bulk of which were broadly classified as having metabolic or cellular maintenance functions. Among the pathways examined, the Tat protein secretion system conferred the only largest fitness contribution during competition infections and a putative Tat-secreted protein, SufI, was also identified as a fitness factor. [4]
Bonny Light Crude Oil Degradative Potental of Species of Citrobacter
Of the various hydrocarbonoclastic bacteria isolated from petroleum polluted IKO River estuarine and freshwater ecosystems, the bacterial isolate, ESW1 and FSW2 identified as Citrobacter amalonaticus strain – FSW2 and Citrobacter amalonaticus strain – ESW1.These efficiently degrade Bonny light petroleum sample recording 82.1 and 69.2% degradation respectively after 28 days of incubation. Biodegradability of the components of Bonny light petroleum decided by gas chromatographic analysis. The chromatographic analysis after 28 days of incubation at 28°C also revealed that in the degradation of Bonny light petroleum , there was a decrease of the entire hydrocarbon content (THC) from 10,906.9 mg L⁻¹ to 1,947.4 mg L⁻¹ and three ,357.9 mg L⁻¹ respectively by FSW2 and ESW1. These results suggest that Citrobacter amalonaticus may be a good candidate for microbial seeding of Bonny light petroleum polluted aquatic ecosystem. [5]
Reference
[1] Mundy, R., MacDonald, T.T., Dougan, G., Frankel, G. and Wiles, S., 2005. Citrobacter rodentium of mice and man. Cellular microbiology, 7(12), (Web Link)
[2] Macaskie, L.E. and Dean, A.C.R., 1984. Cadmium accumulation by a Citrobacter sp. Microbiology, 130(1), (Web Link)
[3] An, S.Y., Min, S.K., Cha, I.H., Choi, Y.L., Cho, Y.S., Kim, C.H. and Lee, Y.C., 2002. Decolorization of triphenylmethane and azo dyes by Citrobacter sp. Biotechnology letters, 24(12), (Web Link)
[4] Citrobacter freundii fitness during bloodstream infection
Mark T. Anderson, Lindsay A. Mitchell, Lili Zhao & Harry L. T. Mobley
Scientific Reports volume 8, (Web Link)
[5] Nkanang, A., Antai, S. and Asitok, A. (2017) “Bonny Light Crude Oil Degradative Potental of Species of Citrobacter”, Microbiology Research Journal International, 21(4), (Web Link)