The Membrane-Bound Transcriptional Regulator CadC Is Activated by Proteolytic Cleavage in Response to Acid Stress▿

Proteolytic processes often participate in signal transduction across bacterial membranes. In Salmonella enterica serovar Typhimurium, the transcriptional regulator CadC activates genes of lysine decarboxylase system in response to external acidification and exogenous lysine. However, the signaling mechanism of CadC activation remains unexplored. We report here that CadC is located on the inner membrane under normal growth conditions but rapidly cleaved under acid stress conditions, leading to the induction of target gene transcription. As full-length CadC is degraded, the N-terminal fragment containing the DNA-binding domain accumulates in the inner membrane. Moreover, we show that C-terminal truncations of CadC abolish its degradation, resulting in complete loss of activator function. Together, these observations suggest that site-specific proteolysis at the periplasmic domain of CadC generates a biologically active form of N-terminal DNA-binding domain to promote target gene activation

Effect of Compatibilizer on Morphology, Thermal, and Rheological Properties of Polypropylene/Functionalized Multi-Walled Carbon Nanotubes Composite

Multi-walled carbon nanotubes (MWCNTs) filled polypropylene (PP) composites were prepared by a corotating intermeshing twin screw extruder. To improve the dispersion of MWCNTs, the surface of MWCNT was modified with 1,10-diaminodecane, and maleic anhydride grafted polypropylene (MA-g-PP) was used as a compatibilizer. Micrographs of well dispersed functionalized MWCNTs (diamine-MWCNT) were observed due to the reaction between MA-g-PP and diamine-MWCNT in PP/ MA-g-PP/diamine-MWCNTs composites. The different behaviors in crystallization and melting temperatures of PP/ MA-g-PP/diamine-MWCNTs composite were observed compared to PP and PP/neat-MWCNT. Especially, the decomposition temperature of the composite was increased by 50??C compared to PP. PP/MA-g-PP/diamine-MWCNTs composite snowed the highest complex viscosity.close161

CadC Has a Global Translational Effect during Acid Adaptation in Salmonella enterica Serovar Typhimurium▿

In Salmonella enterica serovar Typhimurium, the membrane-localized CadC is a transcriptional activator of the cadBA operon, which contributes to the acid tolerance response. Unlike in Escherichia coli, in which transcription of cadC is constitutive, in S. enterica serovar Typhimurium cadC expression is induced by low pH and lysine. Inactivation of cadC suppresses the acid-sensitive phenotype of a cadA mutation, suggesting the existence of other CadC-dependent genes in addition to the cadBA operon. Using a proteomic approach, we identified 8 of the putative CadC-induced proteins and 15 of the putative CadC-repressed proteins. The former include porin proteins OmpC and OmpF. The latter include proteins involved in glycolysis, energy production, and stress tolerance. To better understand the altered levels of OmpC and OmpF, we compared expression of ompR in S. enterica serovar Typhimurium wild-type and cadC mutant strains and determined that CadC exerted a negative influence on ompR transcription. Taken together, our findings strongly suggest that CadC may be a global regulator involved in the OmpR regulatory system during acid adaptation

Asian Plantain (Plantago asiatica) Essential Oils Suppress 3- Hydroxy-3-Methylglutaryl-Co-Enzyme A Reductase Ex- pression

Asian plantain (Plantago asiatica) essential oil (PAEO) contains multiple bioactive compounds, but its potential effects on lipid metabolism have not been examined. PAEO was found to be mostly composed of oxygenated monoterpenes, with linalool as the major component (82·5 %, w/w), measured using GC -MS. Incubation of 0 -200 mg PAEO/ml with HepG2 cells for 24 h resulted in no significant toxicity. Incubation with 0·2 mg PAEO/ml altered the expression of LDL receptor (þ 83 %; P,0·05) and 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase (2 37 %; P, 0·05), as assessed using RT-PCR. LDL oxidation was markedly inhibited by PAEO treatment due to the prevalence of linalool compounds in PAEO. Oral administration of PAEO for 3 weeks in C57BL/6 mice significantly reduced plasma total cholesterol and TAG concentrations by 29 and 46 %, respectively. The mRNA (þ58 %; P, 0·05), but not protein, levels of the LDL receptor were significantly higher, whereas both mRNA and protein levels of HMG-CoA reductase were significantly lower (246 and 211 %, respectively; P,0·05) in the liver of PAEO-fed than of control mice. The mRNA levels of CYP7A1 were marginally reduced in HepG2 cells, but not in mouse liver after PAEO treatment. Thus, PAEO may have hypocholesterolaemic effects by altering the expression of HMG-CoA reductase. Reduced TAG and oxidised LDL may provide additional cardiovascular protective benefits. Plantago asiatica: Essential oils: Cholesterol: 3-Hydroxy-3-methyl-glutaryl-co-enzyme A reductase: Low-density lipoprotein-receptor: Triacylglycerols CHD is a major cause of death in developed societies 1 . Elevated LDL-cholesterol and TAG levels are both independent risk factors for CHD 2 -4 . In addition, the presence of oxidised LDL accelerates atherogenesis 5

Fibrillary glomerulonephritis combined with chronic inflammatory demyelinating polyneuropathy

AbstractA 58-yr-old man presented with leg edema and subacute weakness of his bilateral lower extremities. Urinary and serum immunoelectrophoresis revealed the presence of lambda-type Bence Jones proteins. He was ultimately diagnosed with monoclonal gammopathy of undetermined significance (MGUS). A renal biopsy specimen showed fibrillary glomerulonephritis (FGN), which was randomly arranged as 12–20m nonbranching fibrils in the basement membranes. Immunofluorescence studies were negative for immunoglobulin (Ig)G, IgM, IgA, C3, and kappa light chains in the capillary walls and mesangial areas. A Congo red stain for amyloid was negative. Electromyography and nerve conduction velocity examinations results were compatible with the presence of demyelinating polyneuropathy. This case showed a rare combination of FGN, without Ig deposition, and MGUS combined with chronic inflammatory demyelinating polyneuropathy (CIDP)

Draft genome sequence of Staphylococcus saprophyticus subsp. saprophyticus M1-1, isolated from the gills of a Korean rockfish, sebastes schlegeli hilgendorf, after high hydrostatic pressure processing

A bacterium designated M1-1 was isolated from the gills of a Korean rockfish, Sebastes schlegeli Hilgendorf, after high hydrostatic pressure processing. Studies of 16S rRNA phylogeny and comparative genomics demonstrated that the isolate belongs to Staphylococcus saprophyticus subsp. saprophyticus. Here, we report the draft genome sequence of S. saprophyticus subsp. saprophyticus M1-1 (KACC 16562).

The Prevalence and Clinical Features of Non-responsive Gastroesophageal Reflux Disease to Practical Proton Pump Inhibitor Dose in Korea: A Multicenter Study

Background : /Aims: In Korea, there are no available multicenter data concerning the prevalence of or diagnostic approaches for non-responsive gastroesophageal reflux disease (GERD) which does not respond to practical dose of proton pump inhibitor (PPI) in Korea. The purpose of this study is to evaluate the prevalence and the symptom pattern of non-responsive GERD. Methods : : A total of 12 hospitals who were members of a Korean GERD research group joined this study. We used the composite score (CS) as a reflux symptom scale which is a standardized questionnaire based on the frequency and severity of typical symptoms of GERD. We defined "non-responsive GERD" as follows: a subject with the erosive reflux disease (ERD) whose CS was not decreased by at least 50% after standard-dose PPIs for 8 weeks or a subject with non-erosive reflux disease (NERD) whose CS was not decreased by at least 50% after half-dose PPIs for 4 weeks. Results : : A total of 234 subjects were analyzed. Among them, 87 and 147 were confirmed to have ERD and NERD, respectively. The prevalence of non-responsive GERD was 26.9% (63/234). The rates of non-responsive GERD were not different between the ERD and NERD groups (25.3% vs. 27.9%, respectively, p=0.664). There were no differences between the non-responsive GERD and responsive GERD groups for sex (p=0.659), age (p=0.134), or BMI (p=0.209). However, the initial CS for epigastric pain and fullness were higher in the non-responsive GERD group (p=0.044, p=0.014, respectively). Conclusion : s: In conclusion, this multicenter Korean study showed that the rate of non-responsive GERD was substantially high up to 26%. In addition, the patients with the non-responsive GERD frequently showed dyspeptic symptoms such as epigastric pain and fullness. (Korean J Gastroenterol 2016;68:16-22