Novel Comparative Efficiency of Ozone and Gamma Sterilization on Fungal Deterioration of Archeological Painted Coffin,Saqqara Excavation,Egypt

An archeological wooden painted coffin was excavated in Tety tomb from Saqqara excavation. It belonged to the Ministry of Antiquities. This coffin was discovered in a bad state of conservation with many destroyed big and small pieces in Saqqara stores. Analyses and investigation study were performed on the ground layer of the coffin by X-ray diffraction (XRD), Energy dispersive X ray analysis (EDX) equipped with environmental scanning electron microscopy (ESEM) and Fourier transform infrared spectroscopy (FTIR). Results confirmed that the degradation factors affecting the wooden painted coffin are essentially attributed to direct effects of microbial phenomena, which have lead to many deterioration forms as: macro- and microcracks, hydrated salts, flaking, coloration, scaling and defoliation microbiological spots. Nine deteriorating fungal species were isolated from the painted and ground layers of the tested coffin. Fusarium moniliforme followed by Aspergillus flavus able to significantly solublize calcium salts as major components of the ground layer of archeological wooden coffin. Effect of ozone and Gamma sterilization on growth; lipid, tryptophan oxidation and protein, nucleic acid leakage in the most dominant toxigenic deteriorated fungal species were detected. No mycelial growth was observed at 4 ppm of ozone at all exposure times. As Gamma radiation dose increased over 250 Gy, the growth parameter gradually decreased to reach the lethal dose at 2000 Gy. The production of mycotoxins by the tested toxigenic fungi was completely disappeared under the exposure to 3 ppm and 90 min to ozone.     

Cloning,recombinant production and crystallographic structure of Proliferating Cell Nuclear Antigen from radioresistant archaeon Thermococcus gammatolerans

Thermococcus gammatolerans is a strictly anaerobic; hyperthermophilicarchaeon belongs to the order Thermococcales in the phylum Euryarchaeota. It was extracted from a hydrothermal vent from the Guaymas Basin (Gulf of California, Mexico). Different studies show that T. gammatolerans is one of the most radioresistant organisms known amongst the archaea. This makes it a unique model to study adaptations to the environment and to study DNA repair mechanisms in an organism able to tolerate harsh conditions. A key protein in these mechanisms is the Proliferation Cell Nuclear Antigen (PCNA). Its function is focused on their ability to slide along the DNA duplex and coordinating the activities of proteins mainly related to DNA edition and processing. Analysis of archaeal proteins have proven to be enormously fruitful because much of the information obtained from them can be extrapolated to eukaryotic systems, and PCNA is no exception. Here we report the cloning, recombinant expression and crystallographic structure of PCNA from T. gammatolerans (TgPCNA).     

A novel statistical analysis of cnidocysts in acontiarian sea anemones (Cnidaria, Actiniaria) using generalized linear models with gamma errors

Comparative studies on cnidocysts, involving adequate statistical treatment, are very scarce. Classical statistical tests are frequently used assuming normal frequency distributions of capsule lengths, but many distributions are non-normal in acontiarian sea anemones. A traditional choice in these situations are non-parametric tests, although they are not as powerful as parametric tests. An extension of classical methods was developed by some authors; these models, called Generalized Linear Models (GLM), can be used under certain conditions with non-normal data. In view of the properties of our data, that are positive, skewed and with constant coefficient of variation, a GLM with gamma distribution and inverse link function was chosen to analyse the cnidae of acontia from the species Haliplanella lineata, Tricnidactis errans and Anthothoe chilensis. Graphical analysis of residuals showed that these assumptions were reasonable. This method allowed us to avoid transformation of data set and controversial cases in the limit of significance level. For this task, appropriate subroutines in GLIM language were written. In all cases highly significant differences were found between the specimens considered for every species and nematocyst type (b-rhabdoids, p-rhabdoids B1b and p-rhabdoids B2a).     

Gamma carbonic anhydrase like complex interact with plant mitochondrial complex I

We report the identification by two hybrid screens of two novel similar proteins, called Arabidopsis thaliana gamma carbonic anhydrase like1 and 2 (AtCAL1 and AtCAL2), that interact specifically with putative Arabidopsis thaliana gamma Carbonic Anhydrase (AtCA) proteins in plant mitochondria. The interaction region that was located in the N-terminal 150 amino acids of mature AtCA and AtCA like proteins represents a new interaction domain. In vitro experiments indicate that these proteins are imported into mitochondria and are associated with mitochondrial complex I as AtCAs. All plant species analyzed contain both AtCA and AtCAL sequences indicating that these genes were conserved throughout plant evolution. Structural modeling of AtCAL sequences show a deviation of functionally important active site residues with respect to CAs but could form active interfaces in the interaction with AtCAs. We postulate a CA complex tightly associated to plant mitochondrial complex.     

Exponentiated Exponential Family: An Alternative to Gamma and Weibull Distributions

In this article we study some properties of a new family of distributions, namely Exponentiated Exponential distribution, discussed in Gupta , Gupta , and Gupta (1998). The Exponentiated Exponential family has two parameters (scale and shape) similar to a Weibull or a gamma family. It is observed that many properties of this new family are quite similar to those of a Weibull or a gamma family, therefore this distribution can be used as a possible alternative to a Weibull or a gamma distribution. We present two real life data sets, where it is observed that in one data set exponentiated exponential distribution has a better fit compared to Weibull or gamma distribution and in the other data set Weibull has a better fit than exponentiated exponential or gamma distribution. Some numerical experiments are performed to see how the maximum likelihood estimators and their asymptotic results work for finite sample sizes.     

Plant species diversity and ecological districts of the Sinai desert

Summary Lists of vascular plant species for each of the 12 ecological districts of Sinai were prepared. In all 78,000 observations on altogether 812 species were analyzed. The number of districts where each species occurred was also counted. Linear regressions were calculated for the log-transformed values of species/area, species/altitude and multiple regression of species on both area and altitude.The regression of species on area for the 12 ecological districts of Sinai gave the equation: log S = 1.0309+0.3 log A The value of z=0.3 is higher than 0.222—the measured overall value for the continents and higher than the values for the Sahara, California mainland, the British Isles, and the Netherlands. However, it is lower than the values for the Galápagos Archipelago and the California Islands.The number of species supported in districts characterized by fissured limestone, gravel plains, chalk, marl, sandstones, sands or fissured magmatic and metamorphic rocks is close to the regression of species on area, whereas large outcrops of smooth-faced rocks are relatively richer in total number of species as well as in stenotople species.It is suggested that the high gamma diversity of Sinai as compared with other parts of the world is primarily due to its environmental heterogeneity. Sinai being a meeting place of three phytogeographical regions and to past climatic changes. The effect of smooth-faced rock outcrops as conducive to providing refugia must also be taken into account.This work is based on a comprehensive study of the vegetation of Sinai directed by Prof. G. Orshan, with the collaboration of Dr. A. Shmida, the present author and the late Prof. N.H. Tadmor and Dr. G. Halevy.     

Limited DNA elimination from the irradiated potato parent in fusion products of albino Lycopersicon esculentum and Solanum tuberosum

Summary This paper describes the analysis of the elimination of potato DNA from potato-tomato somatic cell hybrids. The hybrids were obtained by fusion of protoplasts of a cytoplasmic albino tomato genotype with leaf mesophyll protoplasts of a potato genotype carrying the -glucuronidase (GUS) gene of Escherichia coli. The potato protoplasts were either isolated from unirradiated plants or from plants irradiated with 50 or 500 Gy of -rays. Green calli were selected as putative fusion products. The hybridity of these calli was confirmed by isoenzyme analysis. All of the green calli tested contained a potato-specific chloroplast DNA restriction fragment, and most of the calli analysed were positive for -glucuronidase activity. In 72 of the hybrid calli we determined the percentage of potato nuclear DNA using species-specific probes. All of the tested green calli contained a considerable amount of potato genomic DNA, irrespective of the dose of irradiation of the potato parent. The limited degree of potato DNA elimination and the absence of true cybrids are discussed.     

Pretreatment with heat does not affect double-strand breaks DNA rejoining in Chlamydomonas reinhardtii

We aimed to clarify if heat pretreatment could protect Chlamydomonas reinhardtii cells from gamma rays DNA damaging action. It was studied whether: (1) heat pretreatment could accelerate DNA DSB rejoining; (2) chloroplast chaperones (HSP70B, HSP90C) could be involved in protection from radiation-induced DNA DSB.It was obtained that heat pretreatment (37–42 °C) induced minor DNA DSB levels which might be insufficient as signals for DNA DSB repair induction. No correlation between chaperones overproduction and DNA DSB rejoining was shown. These are probably the first data that HSP70B and HSP90C do not protect DNA against radiation-induced damage in a plant model system.