Conserved eukaryotic fusogens can fuse viral envelopes to cells

Caenorhabditis elegans proteins AFF-1 and EFF-1 [C. elegans fusion family (CeFF) proteins] are essential for developmental cell-to-cell fusion and can merge insect cells. To study the structure and function of AFF-1, we constructed vesicular stomatitis virus (VSV) displaying AFF-1 on the viral envelope, substituting the native fusogen VSV glycoprotein. Electron microscopy and tomography revealed that AFF-1 formed distinct supercomplexes resembling pentameric and hexameric "flowers" on pseudoviruses. Viruses carrying AFF-1 infected mammalian cells only when CeFFs were on the target cell surface. Furthermore, we identified fusion family (FF) proteins within and beyond nematodes, and divergent members from the human parasitic nematode Trichinella spiralis and the chordate Branchiostoma floridae could also fuse mammalian cells. Thus, FF proteins are part of an ancient family of cellular fusogens that can promote fusion when expressed on a viral particle.     

Apparent digestibility coefficients for common feed ingredients in formulated diets for tropical catfish, Mystus nemurus (Cuvier & Valenciennes)

Abstract Apparent digestibility coefficients were determined for six feedstuffs, subsequent to their processing into pelleted feed for tropical freshwater catfish, Mystus nemurus (Cuvier & Valenciennes), using a reference diet and test diets composed of 70% reference diet and 30% test ingredient. It was found that most ingredients were fairly well digested except maize and chicken viscera. Digestibility coefficient for protein (P), dry matter (DM) and energy (E) were: (1) fish meal: 97·8% P,97% DM. 77·88% E: (2) soybean meal: 86% P,95·55% DM, 67·89% E: (3) rice bran: 81% P,85·81% DM, 67·93% E: (4) copra meal: 79·90% P, 86% DM, 71·89% E: (5) maize: 51·93% P, 49·0% DM, 63·40% E and (6) chicken viscera: 37% P,29% DM, 52% E. Digestibility coefficients for feedstuffs indicated that animal protein product, such as fish meal and grain by-product, such as rice bran were more digestible than starchy and fibrous feed, e.g. maize. Chicken viscera was poorly digested largely due to inefficient processing. As most feedstuffs were well digested, ingredient selection should, therefore, be based primarily on their protein content, amino acid composition and palatability.     

Identification of quantitative trait loci (QTLs) associated with maintenance of wheat (Triticum aestivum Desf.) quality characteristics under heat stress conditions

The goal of this study was to identify quantitative trait loci (QTLs) associated with the maintenance of wheat grain quality following post-anthesis heat stress in a recombinant inbred line (RIL) population. The response to heat stress was measured using the sodium dodecyl sulfate sedimentation test (SDSS), a significant predictor of bread baking quality. SDSS scores were used to identify QTLs associated with grain quality and QTLs associated with quality stability were identified based on percent change in SDSS score between the heat stress and control treatments. Four QTLs were identified, located one each on linkage groups 1B, 1D, 4A, and 7A. The 1B, 1D, and 4A QTLs were associated with grain quality; the QTL on linkage group 7A was associated with quality stability. To confirm the detected QTLs, eighty advanced lines grown at three Texas nurseries were tested for relationships between allelic polymorphism at QTL linked markers and quality traits. Quality trait stability in the advanced lines was estimated using the coefficient of variability (CV%) of quality traits between nurseries. The analysis supported the relationship of the predicted QTLs on linkage groups 1B, 1D, and 4A with quality traits. The confirmed QTLs may be used in marker assisted selection (MAS) to develop wheat lines possessing superior quality traits. In addition, identification of genetic regions associated with this trait will aid the identification of the underlying genes.     

Demographic and environmental risk factors for infection by Theileria equi in 590 horses in Israel

The prevalence of Theileria equi infection as well as the environmental and demographic risk factors for infection was studied in 590 healthy horses from 46 farms in Israel. The prevalence of T. equi DNA was assessed using a polymerase chain reaction for a segment of the Theileria 18S rRNA gene. The overall prevalence was 26.4% (156/590). There was a significant geographical variation in the prevalence of T. equi infection, ranging from 9.3% (25/270) in the central lowlands to 81.7% (49/60) in the Golan Heights. The prevalence of T. equi infection was found to be significantly associated with management types with more horses with access to pasture being positive. Breed was identified as a risk factor for T. equi infection in a univariate analysis with relatively high infection rates in the Quarter horse and local breeds (41.1% and 36.3% respectively), while ponies and Arabian horses had a relatively low prevalence (10% and 9.1%, respectively). However, since a correlation between geographic location and breed was found, it is difficult to draw definite conclusions regarding this risk factor. Age and gender were not found as risk factors for T. equi infection in this study. The environmental variables that were significantly associated with positivity were relative humidity and minimum land surface temperature at day which both showed negative correlation with T. equi prevalence. In conclusion, Israel was found to be enzootic for T. equi infection, as indicated by the high sub-clinical infection rate, which differed between geographical areas.     

Synthesis and characterization of nanocrystalline CoWO4@silk fibers with antibacterial activity under ultrasound irradiation

The present investigation reports the novel synthesis of CoWO₄ nanoparticles@silk fiber under ultrasound irradiation. The effect of temperature, power of ultrasound irradiation and sequential dipping steps in growth of the CoWO₄ particles were studied. Results show a decrease in the particles size as the temperature and power of irradiation decreased. The fibers containing CoWO₄ nanoparticles were tested for their antibacterial efficacy against E. coli and S. aureus and were found to possess significant antibacterial activity. The results show the CoWO₄ nanoparticles@silk with strongest fluorescence characteristics can be obtained in this method. The physicochemical properties of the nanoparticles were determined by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fluorescence spectroscopy.