40 research outputs found
Defective Mitochondrial tRNA Taurine Modification Activates Global Proteostress and Leads to Mitochondrial Disease
No full textSummary: A subset of mitochondrial tRNAs (mt-tRNAs) contains taurine-derived modifications at 34U of the anticodon. Loss of taurine modification has been linked to the development of mitochondrial diseases, but the molecular mechanism is still unclear. Here, we showed that taurine modification is catalyzed by mitochondrial optimization 1 (Mto1) in mammals. Mto1 deficiency severely impaired mitochondrial translation and respiratory activity. Moreover, Mto1-deficient cells exhibited abnormal mitochondrial morphology owing to aberrant trafficking of nuclear DNA-encoded mitochondrial proteins, including Opa1. The mistargeted proteins were aggregated and misfolded in the cytoplasm, which induced cytotoxic unfolded protein response. Importantly, application of chemical chaperones successfully suppressed cytotoxicity by reducing protein misfolding and increasing functional mitochondrial proteins in Mto1-deficient cells and mice. Thus, our results demonstrate the essential role of taurine modification in mitochondrial translation and reveal an intrinsic protein homeostasis network between the mitochondria and cytosol, which has therapeutic potential for mitochondrial diseases. : Taurine modification of mitochondrial tRNA is associated with mitochondrial disease. Fakruddin et al. find that taurine modification is indispensable for mitochondrial protein translation. The authors also find that deficiency of taurine modification impairs a mitochondrial-cytosolic proteostatic network through an Opa1-dependent mechanism and demonstrate the therapeutic potential of chemical chaperones. Keywords: tRNA, modification, taurine, mitochondria, Opa
Protein Profiling of Bacillus thuringiensis Isolated from Agro-forest Soil in Bangladesh
No full textBacillus thuringiensis (Bt) is a soil bacterium possessing insecticidal characteristics. The aim of the present study was to isolate and characterize Bt strains from the local agro forest soil in Bangladesh. Bt was isolated from 53 soil samples from diverse agro forest fields, and was subjected to further morphological and biochemical characterization. 47 isolates were presumptively confirmed as Bt. All the isolates showed parasporal crystal structure. All of them were resistant to 7% NaCl and 0.001% lysozyme and were motile, haemolytic, lecithinase producer, proteolytic and were unable to survive at 50?C. All of them were able to ferment glucose, maltose and trehalose but did not ferment arabinose, mannitol, sorbitol, xylose, lactose or rhamnose. All the isolates were sensitive to Chloramphenicol, Doxycycline, and Imipenum, whereas they were resistant to Penicillin G and Ampicillin. A study of virulence was also performed whereby 30 isolates were found to exhibit virulence properties. Surface protein analysis by 12% SDS-polyacrylamide gel electrophoresis (PAGE) revealed similar banding patterns as compared to reference strains of Bt (B. thuringiensis subsp. kurstaki HD-73, B. thuringiensis subsp. sotto and B. thuringiensis subsp. japonensis) which further confirmed the identity of the isolates as Bt. In toxin protein analysis by 7.5% SDS-PAGE, molecular weight of the dominant protein band was found to be 140-130 kDathis protein was assumed to be Cry 1 protein. The second most dominant protein with a molecular weight of 70-65 kDa resembled Cry 2 protein, and the third most abundant protein (75 kDa) mimicked the Cry 3 protein. Thus the Bt isolates were shown to produce different classes of Cry proteins, which may confer commercial applications in agriculture. Growth optimization and formulation conditioning research may lead the isolates to be identified as potential strains for bio-insecticide production for use in Bangladesh and beyond
Nucleic acid amplification: Alternative methods of polymerase chain reaction
No full textNucleic acid amplification is a valuable molecular tool not only in basic research but also in application oriented fields, such as clinical medicine development, infectious diseases diagnosis, gene cloning and industrial quality control. A comperehensive review of the literature on the principles, applications, challenges and prospects of different alternative methods of polymerase chain reaction (PCR) was performed. PCR was the first nucleic acid amplification method. With the advancement of research, a no of alternative nucleic acid amplification methods has been developed such as loop mediated isothermal amplification, nucleic acid sequence based amplification, strand displacement amplification, multiple displacement amplification. Most of the alternative methods are isothermal obviating the need for thermal cyclers. Though principles of most of the alternate methods are relatively complex than that of PCR, they offer better applicability and sensitivity in cases where PCR has limitations. Most of the alternate methods still have to prove themselves through extensive validation studies and are not available in commercial form; they pose the potentiality to be used as replacements of PCR. Continuous research is going on in different parts of the world to make these methods viable technically and economically
Hematopoietic stem and progenitor cells integrate microbial signals to promote post‐inflammation gut tissue repair
No full textBone marrow (BM)-resident hematopoietic stem and progenitor cells (HSPCs) are often activated following bacterial insults to replenish the host hemato-immune system, but how they integrate the associated tissue damage signals to initiate distal tissue repair is largely unknown. Here, we show that acute gut inflammation expands HSPCs in the BM and directs them to inflamed mesenteric lymph nodes through GM-CSFR activation for further expansion and potential differentiation into Ly6C(+)/G(+) myeloid cells specialized in gut tissue repair. We identified this process to be mediated by Bacteroides, a commensal gram-negative bacteria that activates innate immune signaling. These findings establish cross-organ communication between the BM and distant inflamed sites, whereby a certain subset of multipotent progenitors is specified to respond to imminent hematopoietic demands and to alleviate inflammatory symptoms.
Construction biotechnology: The promise of sustainable buildings
No full textThe construction industry is one of the thriving industries in the world. There are various modern techniques implemented and latest construction materials are used to build an eco-friendly and sustainable building. Construction Biotechnology is a new scientific and engineering discipline that has been developing exponentially during the last decade. In this biotechnology-based construction, microbially treated construction materials are used. The bio-agents used in construction biotechnologies are pure or enriched with cultures of native microorganisms or microorganisms isolated and activated from the soil. Overall process of construction is also different due to involvement of biotechnology-derived processes and technologies. Biotechnology-based construction has shown potential of cost-effectiveness which renders such construction technologies promising in the current era. Architects, engineers, and people involved with construction are suggesting these biotechnology-based construction technologies for ecofriendliness and high sustainability of these novel construction materials. As a field, biotechnology offers countless solutions to common environmental problems well beyond the construction industr
Cdk5rap1 バイカイ セイ 2 メチルチオ N6 イソペンテニル アデノシン シュウショク ワ カク ニ ユライ スル RNA シュ ニ ワ ソンザイ シナイ
No full text博士(医学）熊本大
Antimicrobial and antioxidant activities of Saccharomyces cerevisiae IFST062013, a potential probiotic
No full textAbstract
Background
Probiotic yeast has become a field of interest to scientists in recent years.
Methods
Conventional cultural method was employed to isolate and identify yeast and standard methods were used to determine different probiotic attributes, antimicrobial and antioxidant properties.
Results
This study reports potential probiotic properties of a strain of S. cerevisiae IFST 062013 isolated from fruit. The isolate is tolerant to a wide range of temperature and pH, high concentration of bile salt and NaCl, gastric juice, intestinal environment, \u3b1-amylase, trypsin and lysozyme. It can produce organic acid and showed resistance against tetracycline, ampicillin, gentamycin, penicillin, polymixin B and nalidixic acid. It can assimilate cholesterol, can produce killer toxin, vitamin B12, glutathione, siderophore and strong biofilm. It showed moderate auto-aggregation ability and cell surface hydrophobicity. The isolate can produce enzymes such as amylase, protease, lipase, cellulose, but unable to produce galactosidase. The isolate can\u2019t produce gelatinase and DNase. The isolate showed moderate anti-microbial activity against bacteria and fungi and cell lysate showed better antimicrobial activity than whole cell and culture supernatant. Again, the isolate showed better anti-bacterial activity against gram negative bacteria than gram positive. The isolate showed strong antioxidant activity, reducing power, nitric oxide and hydroxyl radical scavenging activity, significant brine shrimp cytotoxicity and acute toxicity and metal ion chelating activity. The isolate did not induce any detectable change in general health of mice upon oral toxicity testing and found to be safe in mouse model. The isolate improve lymphocyte proliferation and cytokine production in treated mice.
Conclusions
Such isolate could be potential as probiotic to be used therapeutically
Prevalence of extended-spectrum β-lactamase positive bacteria in radiologically positive urinary tract infection
No full textA 6-year retrospective study of bloodstream Salmonella infection and antibiotic susceptibility of Salmonella enterica serovar Typhi and Paratyphi in a tertiary care hospital in Dhaka, Bangladesh
No full textAbstractObjectivesBloodstream infections (BSI) are a serious cause of morbidity and mortality worldwide. Emerging antimicrobial drug resistance among bacterial pathogens causing BSI can limit therapeutic options and complicate patient management. This retrospective study was conducted to determine trends in Salmonella BSI and antibiotic susceptibility patterns over 6 years (2008–2013) in a tertiary care hospital in Dhaka, Bangladesh.MethodsA total of 3584 blood samples were collected from patients with clinically diagnosed enteric fever at Dhaka Medical College Hospital, Dhaka from January 2008 to December 2013. Isolates of Salmonella enterica serovars Typhi and Paratyphi were identified by standard microbiological and biochemical procedures.ResultsA total of 168 isolates of S. enterica serovar Typhi and 160 isolates of S. enterica serovar Paratyphi were found. The average prevalence rate of Salmonella in the blood was 9.15%. Young patients, neonates, and elderly individuals were more prone to Salmonella infection than other patients, and females were more susceptible to Salmonella septicemia than males. Among Salmonella spp. isolates, 20.92% were multidrug resistant and showed high resistance against amoxicillin, trimethoprim–sulfamethoxazole, ciprofloxacin, nalidixic acid, and chloramphenicol. Resistance rates to cefipime, cefixime, and ceftriaxone are increasing slowly. Among Salmonella spp. isolates, 57.01% showed extended-spectrum β-lactamase production capability.ConclusionSpecific antibiotic utilization strategies such as antibiotic restriction, combination therapy and usage according to standard antimicrobial susceptibility testing may help decrease or prevent the emergence of resistance and incidence of BSI
