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This work describe the synthesis of a series of Europium ion (Eu2+) activated calcium chlorophosphate Ca2−XPO4Cl:xEu2+, x= 0.01, 0.015, 0.02, 0.05 and 0.10) phosphors annealed at various temperature. This phosphor is synthesized by wet chemical synthesis. This synthesis method is more efficient than conventional solid state synthesis. The formation of crystalline structure of Ca2PO4Cl of the synthesized phosphor is confirmed by X-ray diffraction analysis. The photoluminescence characterization is carried out and optimal Eu2+concentration is determined as 2 mol.%. The excitation spectra of Ca2PO4Cl:Eu2+phosphor shows prominent excitation band around 380 nm. Upon excitation at 385 nm, the phosphor emits light in the range 400 nm to 520 nm peaking at 452 nm. The Commission Internationale de I'Eclairage (CIE) chromaticity coordinates of the phosphor are calculated to be Cx= 0.154 and Cy= 0.022. The PL emission of the prepared phosphor is more intense than commercial BaMgAl10O17:Eu2+BAM phosphor. This phosphor may be a candidate for the application in solid state lighting as blue emitting component.

The enzyme families of protein disulphide isomerases (PDI) and cyclophilins catalyse the isomerisation of disulphide bonds and the rotation of Xaa-Pro peptide bonds in nascent proteins, respectively, making them excellent candidates for regulating the deposition of storage proteins in wheat. This study aimed to isolate and characterise clones encoding cyclophilins and PDIs from a wheat endosperm cDNA library. A number of cDNA clones were isolated, of which three different cDNAs each of PDI and cyclophilin were selected for complete sequencing. The three PDI cDNAs encoded putative protein products of 513 or 516 amino acids, all exhibiting conserved sequences for the N-terminal signal peptide, the two thioredoxin-like domains at the catalytic sites and the C-terminal ER retention signal. The three cyclophilin cDNAs exhibited 68–87% identity to other reported cyclophilins and encoded putative protein products of 171 amino acids containing the conserved tryptophan residue and a 7 amino acid sequence unique to certain plant cyclophilins. The sequence variations within and outside the coding regions of all the cDNAs suggest that both enzymes are encoded by multiple genes. This information will allow further investigations into the roles of these enzymes in storage protein deposition in the developing endosperm and thus in wheat quality.

The waxy proteins from a number of genetic backgrounds of wheat and its progenitors were analyzed by SDS-PAGE. The deduced amino acid sequences of the waxy proteins of three diploid progenitor species indicated several key amino acid substitutions, which could explain the differences observed in the electrophoretic mobilities of the wheat waxy proteins. A slight difference observed in the apparent molecular weight of the WX-A1 protein of diploid and polyploid wheat was explained by amino acid substitutions or variations in predicted protein structures. Further, twelve different partial genomic clones, representing the individual waxyloci of the various diploid, tetraploid and hexaploid wheats, were isolated and compared. The results indicated significant variations in intron 4 and led to identification of sequences unique to the individual waxygenes and genomes of wheat and its proposed progenitors. The sequence variations observed have a great potential for development as molecular markers for identification of specific waxyloci and study of the various waxy mutants of wheat.

The increase in uterine oxytocin receptor concentrations over the late luteal phase of the oestrous cycle in sheep is thought to play an important role in the regulation of the duration of the cycle by facilitating the effect of oxytocin on uterine prostaglandin release. Experiments indicated that oxytocin receptor mRNA expression in the endometrium was high at oestrus compared with at days 2, 7 and 12 of the oestrous cycle. The amount of oxytocin receptor mRNA expression in the pituitary gland did not show any significant differences during the oestrous cycle. Oxytocin receptor cDNA was obtained and characterized from ovine uterine endometrium on day 15 of the oestrous cycle, using RT-PCR techniques, to study the mechanisms underlying the resolution of oxytocin receptor expression. The cDNA sequence for the oxytocin receptor gene in sheep was found to be similar to that described previously, except for a difference of seven nucleotides. These nucleotide differences resulted in changes in four of the deduced amino acids in the oxytocin receptor sequence. The heterogeneity of the different sized oxytocin receptor transcripts in sheep is due, at least in part, to the alternative use of polyadenylation sites. Northern hybridization confirmed that the oxytocin receptor gene is expressed in ovine corpus luteum. The investigations on oxytocin receptor gene expression indicate that the patten of oxytocin receptor gene expression in sheep is not only tissue-specific, but also highly function-related. Evidence was obtained of mRNA editing in both the coding and the 3'-untranslated (3'UTR) regions of oxytocin receptor gene transcripts in ovine endometrium; this was the first demonstration of this phenomenon for oxytocin receptor mRNA. The present results indicate that the observed differences in oxytocin receptor mRNA sequences for the different oxytocin receptor populations in endometrium are due to mRNA editing. mRNA editing of oxytocin receptor transcripts may be reflected in changes in the amino acid composition of the carboxyl terminus of the receptor, which would explain the differences in the observed responses to an oxytocin challenge.

The xylanase gene of Cellulomonas sp. NCIM 2353 was cloned in pUC 18 and selected by growth on xylan as the sole carbon source. The functional clone harboured the recombinant plasmid with an insert of 1.42 kbp, as determined by restriction mapping and Southern hydridization. The clone secreted a xylanase of 45 000 mol. wt. as determined by Western blot analysis using specific antixylanase antibodies. The DNA insert carried the full structural gene along with its promoter and possibly regulatory sequences, since xylanase activity in the clone Cs11 was inducible by xylan.

The emphasis of the present work was mainly to develop process conditions for a better yield and purity of m-cresol which is used as a starting material for the production of menthol. Experiments were conducted to isolate m-cresol by a sulfonation-desulfonation method. The various parameters studied included reaction temperature, weight ratio of cresols to sulfuric acid, and reaction time. The best conditions were reaction temperature 80°C, reaction time 5 h, and w/w ratio of cresols to sulfuric acid of 1:1. Under these conditions the conversion of m-cresol to m-cresol sulfonate was 96.5%. After desulfonation the overall recovery of the product m-cresol, based on the amount of m-cresol in the initial crude mixture, was 63%. The purity of the final product was more than 80%. The effects of various impurities (o-, p-cresols, and phenols) are discussed.

The copper-sensitive/temperature-sensitive phenotype of the Escherichia coli cutE mutant has been complemented by cloning wild-type genomic DNA into the plasmid vector pACYC184 and selecting transformants on medium containing 4 mM copper sulfate and chloramphenicol. One of these complementing clones, designated pCUT1, contained a 5.6-kb BamHI fragment. This recombinant plasmid transformed cutE, allowing wild-type growth of transformants on medium containing copper sulfate. Complementation of copper sensitivity was assessed by comparing both cell survival at increased copper levels and the results of 64Cu accumulation assays. An EcoRI subclone, 2.3 kb in size, was also shown to complement cutE when cloned in both medium- and high-copy-number vectors and was completely sequenced. This clone was mapped on the E. coli physical map at 705.70 to 707.80 kb. A series of subclones was constructed from pCUT1 and used to show that the large open reading frame of the translated sequence was essential for complementation. This open reading frame has a potential upstream promoter region, ribosome-binding site, and transcriptional terminator and encodes a putative protein of 512 amino acids that contains a region showing some homology to a putative copper-binding site.