Four products from Escherichia coli pseudogenes increase hydrogen production

Pseudogenes are considered to be nonfunctional genes that lack a physiological role. By screening 3985 Escherichia coli mutants using chemochromic membranes, we found four pseudogenes involved in hydrogen metabolism. Knockouts of pseudogenes ydfW and ypdJ had a defective hydrogen phenotype on glucose and formate, respectively. Also, the knockout of pseudogene yqiG formed hydrogen from formate but not from glucose. For the yqiG mutant, 100% hydrogen recovery was obtained by the complementation of YqiG via a plasmid. The knockout of pseudogene ylcE showed hydrogen deficiency in minimal media which suggested that the role of YlcE is associated with cell growth. Hence, the products of these four pseudogenes play an important physiological role in hydrogen production in E. coli.     

Optimized retroviral transduction protocol which preserves the primitive subpopulation of human hematopoietic cells

Though both low-speed centrifugation and the use of fibronectin (Retronectin) fragments increase gene transduction efficiency, they still do not overcome the adverse effects of the presence of virus-containing medium (VCM). In this study, we improved transduction efficiency of primitive human hematopoietic cells by optimizing the conditions for preadsorbing culture dishes with retrovirus using a centrifugation protocol allowing subsequent infection to be carried out in the absence of VCM. We also demonstrate that preadsorbing tissue culture plates with retrovirus is dependent on the volume of VCM used for preadsorption and the length of centrifugation and the type of plasticware used but not on the temperature of centrifugation (4-33 degrees C). Direct exposure of CD34+ target cells to VCM depletes the primitive CD34+CD38neg subpopulation by more than 30%, whereas the optimized VCM-free infection protocol targets this population with equivalent efficiency but had no detrimental effects on CD34+CD38neg frequency. In summary, we demonstrate a high-frequency transduction protocol which preserves the therapeutically relevant primitive subpopulation of human hematopoietic cells.     

Risk Factors and Prevalence of Helicobacter pylori in Five Largest Islands of Indonesia: A Preliminary Study

The prevalence of Helicobacter pylori infection in Indonesia is still controversial and mainly investigated in the largest ethnic group, Javanese. We examined the prevalence of H. pylori infection using four different tests including culture, histology confirmed by immunohistochemistry and rapid urease test. We also analyzed risk factors associated with H. pylori infection in five largest islands in Indonesia. From January 2014–February 2015 we consecutively recruited a total of 267 patients with dyspeptic symptoms in Java, Papua, Sulawesi, Borneo and Sumatera Island. Overall, the prevalence of H. pylori infection was 22.1% (59/267). Papuan, Batak and Buginese ethnics had higher risk for H. pylori infection than Javanese, Dayak and Chinese ethnics (OR = 30.57, 6.31, 4.95; OR = 28.39, 5.81, 4.61 and OR = 23.23, 4.76, 3.77, respectively, P <0.05). The sensitivity and specificity for RUT and culture were 90.2%, 92.9% and 80.5%, 98.2%, respectively. The patients aged 50–59 years group had significantly higher H. pylori infection than 30–39 years group (OR 2.98, P = 0.05). Protestant had significantly higher H. pylori infection rate than that among Catholic (OR 4.42, P = 0.008). It was also significantly lower among peoples who used tap water as source of drinking water than from Wells/river (OR 9.67, P = 0.03). However only ethnics as become independent risk factors for H. pylori infection. Although we confirmed low prevalence of H. pylori in Javanese; predominant ethnic in Indonesia, several ethnic groups had higher risk of H. pylori infection. The age, religion and water source may implicate as a risk factor for H. pylori infection in Indonesia.     

Effect of azithromycin on enhancement of methane production from waste activated sludge

In the methane production from waste activated sludge (WAS), complex bacterial interactions in WAS have been known as a major contribution to methane production. Therefore, the influence of bacterial community changes toward methane production from WAS was investigated by an application of antibiotics as a simple means for it. In this study, azithromycin (Azm) as an antibiotic was mainly used to observe the effect on microbial changes that influence methane production from WAS. The results showed that at the end of fermentation, Azm enhanced methane production about twofold compared to control. Azm fostered the growth of acid-producing bacterial communities, which synthesized more precursors for methane formation. DGGE result showed that the hydrolysis as well as acetogenesis stage was improved by the dominant of B1, B2 and B3 strains, which are Clostridium species. In the presence of Azm, the total population of archaeal group was increased, resulting in higher methane productivity achievement.     

Exploring cultural differences in wildlife value orientations using student samples in seven nations

Biodiversity and Conservation - Understanding differences in the way people think about wildlife across countries is important as many conservation challenges transcend jurisdictions. We explored...