Insight in to the phylogeny of polyhydroxyalkanoate biosynthesis: horizontal gene transfer

Polyhydroxyalkanoates (PHAs) are gaining more and more importance the world over due to their structural diversity and close analogy to plastics. Their biodegradability makes them extremely desirable substitutes for synthetic plastics. PHAs are produced in organisms under certain stress conditions. Here, we investigated 253 sequenced (completely and unfinished) genomes for the diversity and phylogenetics of the PHA biosynthesis. Discrepancies in the phylogenetic trees for phaA, phaB and phaC genes of the PHA biosynthesis have led to the suggestion that horizontal gene transfer (HGT) may be a major contributor for its evolution. Twenty four organisms belonging to diverse taxa were found to be involved in HGT. Among these, Bacillus cereus ATCC 14579 and Xanthomonas axonopodis pv. citri str. 306 seem to have acquired all the three genes through HGT events and have not been characterized so far as PHA producers. This study also revealed certain potential organisms such as Streptomyces coelicolor A3(2), Staphylococcus epidermidis ATCC 12228, Brucella suis 1330, Burkholderia sp., DSMZ 9242 and Leptospira interrogans serovar lai str. 56601, which can be transformed into novel PHA producers through recombinant DNA technology.     

Effects of various concentrations of uranium tailings on certain growth and biochemical parameters in sunflower

Effects of different concentrations (25, 50, 75 and 100%) of uranium tailings conditioned with garden soil on growth and biochemical parameters in sunflower were studied. The shoot and root length, fresh and dry mass as well as leaf area and chlorophyll contents showed significant negative correlation with the applied uranium tailing concentrations. The influence on plant growth was also measured in terms of Tolerance Index (TI) and Grade of Growth Inhibition (GGI). Yellowing of leaves was recorded in all the tailing concentrations. Soluble proteins (leaf) showed significant enhancement as the concentration of uranium tailing increased indicating a breakdown of structural insoluble proteins. Survival of sunflower plants over 100 days on higher tailing concentrations (up to 75%) showed that sunflower may be helpful in revitalization of uranium mining waste.     

Genetic Diversity of Cryptosporidium spp. in Captive Reptiles

The genetic diversity of Cryptosporidium in reptiles was analyzed by PCR-restriction fragment length polymorphism and sequence analysis of the small subunit rRNA gene. A total of 123 samples were analyzed, of which 48 snake samples, 24 lizard samples, and 3 tortoise samples were positive for Cryptosporidium. Nine different types of Cryptosporidium were found, including Cryptosporidium serpentis, Cryptosporidium desert monitor genotype, Cryptosporidium muris, Cryptosporidium parvum bovine and mouse genotypes, one C. serpentis-like parasite in a lizard, two new Cryptosporidium spp. in snakes, and one new Cryptosporidium sp. in tortoises. C. serpentis and the desert monitor genotype were the most common parasites and were found in both snakes and lizards, whereas the C. muris and C. parvum parasites detected were probably the result of ingestion of infected rodents. Sequence and biologic characterizations indicated that the desert monitor genotype was Cryptosporidium saurophilum. Two host-adapted C. serpentis genotypes were found in snakes and lizards.     

An improved method for isolation of anti-viper venom antibodies from chicken egg yolk

The production of antibodies and its purification from mammalian blood has been found low yielding and laborious. Therefore, anti snake venom antibodies for therapeutic use is obtained mostly as polyvalent whole serum or partially purified polyvalent immunoglobulin. The side effects of anti snake venom (ASV) therapy are mainly serum sickness and renal failure, which may be reduced by using sufficiently pure antibodies. Therefore, we have standardized a simple method for production of purified antivenom. Here, we present the development of polyclonal antibodies against viper venom in hens and its isolation from the egg yolk of immunized birds. We have modified the reported methods of purification of immunoglobulin from egg yolk, and thus yielded 90% purity of the protein. The modified method involves only two steps, such as removal of lipids from the diluted egg yolk by a freeze-thaw cycle and centrifugation, followed by gel filtration on Biogel P-150. The advantages are that the process is very simple, and from one egg, 100+/-20 mg of pure immunoglobulin is obtained. The antibodies are present in the egg for up to 100 days after the immunization. Thus, using small amounts of venom, a large quantity of the immunoglobulin is obtained in a sufficiently pure form. The antigen binding ability of the pure antibody is found good by the Ouchterlony's double diffusion experiment.     

Blockade of morphine-withdrawal body shakes by haloperidol

Intravenous injections of morphine sulfate in escalating doses caused narcotic dependence, and the rats showed a high rate of “wet- dog” like body shakes during withdrawal. Intraperitoneal injections of haloperidol suppressed these body shakes in a dose dependent manner.     

Evaluation of Inoculum Addition To Stimulate In Situ Bioremediation of Oily-Sludge-Contaminated Soil

A full-scale study evaluating an inoculum addition to stimulate in situ bioremediation of oily-sludge-contaminated soil was conducted at an oil refinery where the indigenous population of hydrocarbon-degrading bacteria in the soil was very low (10³ to 10⁴ CFU/g of soil). A feasibility study was conducted prior to the full-scale bioremediation study. In this feasibility study, out of six treatments, the application of a bacterial consortium and nutrients resulted in maximum biodegradation of total petroleum hydrocarbon (TPH) in 120 days. Therefore, this treatment was selected for the full-scale study. In the full-scale study, plots A and B were treated with a bacterial consortium and nutrients, which resulted in 92.0 and 89.7% removal of TPH, respectively, in 1 year, compared to 14.0% removal of TPH in the control plot C. In plot A, the alkane fraction of TPH was reduced by 94.2%, the aromatic fraction of TPH was reduced by 91.9%, and NSO (nitrogen-, sulfur-, and oxygen-containing compound) and asphaltene fractions of TPH were reduced by 85.2% in 1 year. Similarly, in plot B the degradation of alkane, aromatic, and NSO plus asphaltene fractions of TPH was 95.1, 94.8, and 63.5%, respectively, in 345 days. However, in plot C, removal of alkane (17.3%), aromatic (12.9%), and NSO plus asphaltene (5.8%) fractions was much less. The population of introduced Acinetobacter baumannii strains in plots A and B was stable even after 1 year. Physical and chemical properties of the soil at the bioremediation site improved significantly in 1 year.     

Synthesis and characterization of biologically significant 5,5′-(1,4-phenylene)bis(1-N-alkoxyphthalimido-3-aryl-2-pyrazoline) derivatives

A facile synthesis of 5,5′-(1,4-phenylene)bis(3-aryl-2-pyrazolines) 4a-g has been achieved by the cyclo-addition reaction of hydrazine hydrate with bis-substituted chalcones 3a-g, which in turn were prepared by the Clasien-Schmidt condensation of p-substituted acetophenones 1a-g with terephthaldehyde. Condensation of 4a-g with ω-bromoalkoxyphthalimides 5a-b afforded the titled compounds 6a-n, some of which exhibited significant antimalarial as well as antimicrobial activity.     

Vagal afferent responses to fatty acids of different chain length in the rat

The role of cholecystokinin (CCK) in the effect of dietary lipid on proximal gastrointestinal function and satiety is controversial. Recent work suggests that fatty acid chain length may be a determining factor. We investigated the mechanism by which long- and short-chain fatty acids activate jejunal afferent nerves in rats. Whole mesenteric afferent nerve discharge was recorded in anaesthetized male Wistar rats during luminal perfusion of saline, sodium oleate, and sodium butyrate (both 10 mM). Both fatty acids evoked characteristic afferent nerve responses, distinct from the mechanical response to saline, that were abolished in rats following chronic subdiaphragmatic vagotomy. The effect of oleate was abolished by the CCK-A receptor antagonist Devazepide (0.5 mg/kg), whereas the effect of butyrate persisted despite pretreatment with either Devazepide or a combination of the calcium channel inhibitors nifedipine (1 mg/kg) and the omega-conotoxins GVIA and SVIB (each 25 microg/kg). In summary, long- and short-chain fatty acids activate intestinal vagal afferents by different mechanisms; oleate acts via a CCK-mediated mechanism and butyrate appears to have a direct effect on afferent terminals.     

Activated PMN Exosomes: Pathogenic Entities Causing Matrix Destruction and Disease in the Lung

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