A calcium wave mediated by gap junctions coordinates a rhythmic behavior in C. elegans

Intercellular calcium waves can be observed in adult tissues, but whether they are instructive, permissive, or even required for behavior is predominantly unknown. In the nematode Caenorhabditis elegans, a periodic calcium spike in a pacemaker cell initiates a calcium wave in the intestine. The calcium wave is followed by three muscle contractions that comprise the defecation motor program. Normal wave propagation requires the pannexin gap-junction subunit INX-16 at the interfaces of the intestinal cells. In the absence of this gap-junction subunit, calcium waves are frequently absent. The remaining waves are slow, initiate at abnormal locations, or travel in the opposite direction. Abnormal waves are associated with parallel effects in the first step of the motor program: The contractions of the overlying muscles fail to propagate beyond the pacemaker cell, are slow, initiate in abnormal locations, or are reversed. Moreover, the last two motor steps are predominantly absent. Finally, the absence of this gap-junction subunit also affects the reliability of the pacemaker cell; cycle timing is often irregular. These data demonstrate that pannexin gap junctions propagate calcium waves in the C. elegans intestine. The calcium waves instruct the motor steps and regulate the pacemaker cell's authority and reliability.     

Co-Occurrence of TDP-43 Mislocalization with Reduced Activity of an RNA Editing Enzyme, ADAR2, in Aged Mouse Motor Neurons

TDP-43 pathology in spinal motor neurons is a neuropathological hallmark of sporadic amyotrophic lateral sclerosis (ALS) and has recently been shown to be closely associated with the downregulation of an RNA editing enzyme called adenosine deaminase acting on RNA 2 (ADAR2) in the motor neurons of sporadic ALS patients. Because TDP-43 pathology is found more frequently in the brains of elderly patients, we investigated the age-related changes in the TDP-43 localization and ADAR2 activity in mouse motor neurons. We found that ADAR2 was developmentally upregulated, and its mRNA expression level was progressively decreased in the spinal cords of aged mice. Motor neurons normally exhibit nuclear ADAR2 and TDP-43 immunoreactivity, whereas fast fatigable motor neurons in aged mice demonstrated a loss of ADAR2 and abnormal TDP-43 localization. Importantly, these motor neurons expressed significant amounts of the Q/R site-unedited AMPA receptor subunit 2 (GluA2) mRNA. Because expression of unedited GluA2 has been demonstrated as a lethality-causing molecular abnormality observed in the motor neurons, these results suggest that age-related decreases in ADAR2 activity play a mechanistic role in aging and serve as one of risk factors for ALS.     

ERRgamma tethers strongly bisphenol A and 4-alpha-cumylphenol in an induced-fit manner

A receptor-binding assay and X-ray crystal structure analysis demonstrated that the endocrine disruptor bisphenol A (BPA) strongly binds to human estrogen-related receptor γ (ERRγ). BPA is well anchored to the ligand-binding pocket, forming hydrogen bonds with its two phenol-hydroxyl groups. In this study, we found that 4-α-cumylphenol lacking one of its phenol-hydroxyl groups also binds to ERRγ very strongly. The 2.0 Å crystal structure of the 4-α-cumylphenol/ERRγ complex clearly revealed that ERRγ’s Leu345-β-isopropyl plays a role in the tight binding of 4-α-cumylphenol and BPA, rotating in a back-and-forth induced-fit manner.     

Development of rapid coagulase serotyping method by PCR and microplate hybridization

We developed a novel PCR-based method for coagulase serotyping. Coagulase gene amplicons biotinylated by PCR were identified by microplate hybridization (MPH) using serotype-specific probes. The conventional serotyping method, which is strongly dependent on coagulase activity, may sometimes give a mistaken determination of the serotype, especially in cases where there is high coagulase activity. In contrast, the results of PCR-MPH are not affected by coagulase activity. Furthermore, once the isolated colonies are obtained, it only takes 3 h to perform PCR-MPH, and the interpretation of the results is entirely objective. We compared PCR-MPH with the conventional method for 90 strains of coagulase-producing Staphylococcus aureus. The same results were found for both the PCR-MPH and conventional methods, and thus, our results indicate that PCR-MPH is a rapid, objective, and reliable method for coagulase serotyping.     

Pretreatment of woody and herbaceous biomass for enzymatic saccharification using sulfuric acid-free ethanol cooking

A sulfuric acid-free ethanol cooking (SFEC) treatment was developed to achieve complete saccharification of the cellulosic component of eucalyptus and baggase flour, thereby avoiding the problems associated with the use of strong acid catalysts. Cutter-milled flours were exposed to an ethanol (EtOH)/water/acetic acid mixture in an autoclave. Enzymatic hydrolysis experiments of the pretreated samples demonstrated that almost complete conversion of the cellulosic components to glucose was achieved under optimal conditions. A large-scale trial revealed that there was little consumption of in-feed EtOH during SFEC; therefore, it is considered that most part EtOH used can be essentially recovered and reused. Field emission scanning electron microscopy showed that SFEC induced the formation of pores ranging in size from approximately 10 to several 100nm. It can be assumed that the porous surface was due to the partial removals of lignin and hemicellulose, which improved the accessibility of the enzyme onto the substrate.     

Characteristics of a rice beer (zutho) and a yeast isolated from the fermented product in Nagaland,India

Rice beer, known locally as zutho was collected in the Kohima district in Nagaland, India, and subjected to analytical and microbiological characterization. Zutho was a whitish porridge-like slurry containing 5.0% (v/v) ethanol. Volatile esters and higher alcohols, such as ethyl acetate and 3-methylbutanol, were detected in this indigenous alcoholic beverage by gas chromatography. The pH and acidity of zutho were 3.6 and 5.1, respectively. Zutho had a fruity aroma and sour taste and its unique aroma had characteristics similar to those of Japanese sake and sprouted rice sake. A fermentation yeast isolated from zutho was identified as being a strain of Saccharomyces cerevisiae and was found to be suitable as the brewing yeast for ethanol fermentation.     

Characteristics of Egyptian boza and a fermentable yeast strain isolated from the wheat bread

A sample of indigenous beer, boza was collected at Cairo, Egypt and analysed. Boza was an off-white porridge-like slurry containing 3.8% (v/v) ethanol. Volatile esters and higher alcohols such as ethyl acetate and isoamyl alcohol were detected in the boza by gas chromatography. The pH of the boza was 3.7. Organoleptically, this alcoholic beverage had an estery flavour and a sour taste. A fermentable yeast strain EG1 was isolated from the material wheat bread and identified, and was considered to resemble Candida krusei. The rice sake made with the yeast strain C. krusei EG1 at 30 °C contained 11.7% ethanol, 74.1 mg/l ethyl acetate and its pH value was 4.2.