Effects of troponin I phosphorylation on conformational exchange in the regulatory domain of cardiac troponin C.

Conformational exchange has been demonstrated within the regulatory domain of calcium-saturated cardiac troponin C when bound to the NH2-terminal domain of cardiac troponin I-(1-80), and cardiac troponin I-(1-80)DD, having serine residues 23 and 24 mutated to aspartate to mimic the phosphorylated form of the protein. Binding of cardiac troponin I-(1-80) decreases conformational exchange for residues 29, 32, and 34. Comparison of average transverse cross correlation rates show that both the NH2- and COOH-terminal domains of cardiac troponin C tumble with similar correlation times when bound to cardiac troponin I-(1-80). In contrast, the NH2- and COOH-terminal domains in free cardiac troponin C and cardiac troponin C bound cardiac troponin I-(1-80)DD tumble independently. These results suggest that the nonphosphorylated cardiac specific NH2 terminus of cardiac troponin I interacts with the NH2-terminal domain of cardiac troponin C.     

Trilobites Plicatolina lucida Lazarenko from the Upper Cambrian of the Kharaulakh Mountains (Northeastern Siberian Platform)

A collection of trilobites of the genus Plicatolina Shaw, 1951 from the upper Ogon’or Formation, Cambrian Section, Chekurovka Anticline (northeastern Siberian Platform, Kharaulakh Mountains), is studied. It is shown that all specimens of this collection belong to the same species, Plicatolina lucida Lazarenko, 1966, but represent different age stages. It is also shown that species of the genus Plicatolina (P. quadrata Pokrovskaya, 1966 and P. yakutica Pokrovskaya, 1966) described from the Upper Cambrian of the Siberian Platform are probably synonyms of P. lucida.     

Bacterial conversion of glycerol to beta-hydroxypropionaldehyde

beta-hydroxypropionaldehyde (3-HPA) can be oxidized to acrylic acid, an industrially important chemical used in the manufacture of synthetic plastics and other polymers. Of 19 genera and 55 strains tested, 3 Klebsiella and 2 Enterobacter strains produced 3-HPA. The most efficient strain was Klebsiella pneumoniae NRRL B-4011. Under optimum conditions (28 degrees C; 40 g of semicarbazide hydrochloride per liter, 70 g of glycerol per liter; and pH 6.0), 3.1 g of B-4011 cells per liter accumulated 22 g of 3-HPA per liter at a specific rate of 0.83 g/g per h; however, 14.5 g of cells per liter accumulated 46 g of 3-HPA per liter at a specific rate of 0.41 g/g per h.     

Hatchery selection promotes boldness in newly hatched brown trout (Salmo trutta): implications for dominance

By using newly hatched (approximately 2 weeks old) brown trout(Salmo trutta) from six families of wild and six families ofsea-ranched origin (seventh generation), we tested the hypothesesthat (1) the hatchery environment selects for increased boldness,and (2) boldness predicts dominance status. Sea-ranched troutspend their first 2 years in the hatchery before being releasedinto the wild at the onset of seaward migration. Trout werepresented with a novel object (tack) and with food (brine shrimp),and their responses were measured and scored in terms of boldness.Siblings with increasing difference in boldness were then pairedin dyadic contests. Fish of sea-ranged origin were on averagebolder than were fish of wild origin, and bolder individualswere more likely to become dominant regardless of origin. Boldnesswas not related to RNA levels, indicating that bold behaviorwas not a consequence of higher metabolism or growth rate. Neitherwas size a predictor of bold behavior or the outcome of dyadiccontests. These results are consistent with studies on olderlife stages showing increased boldness toward predators in hatchery-selectedfish, which suggests that behavioral consequences of hatcheryselection are manifested very early in life. The concordancebetween boldness and dominance may suggest that these behaviorsare linked in a risk prone-aggressive phenotype, which may bepromoted by hatchery selection. However, we also found significantvariation in behavioral and growth-related traits among families,suggesting that heritable variation has not been exhausted bysea-ranching procedures.     

Development of sporeless/low sporing strains of Pleurotus through mutation

Summary The sporophores of Pleurotus are gymnocarpous and continuously release spores in the atmosphere causing respiratory allergies like hay fever and farmer’s lung disease among workers. The allergy is caused by the antigens present on the walls of the spores. Apart from this, during commercial production, these spores settle on the fruit bodies, germinate and form a velvety film which gives an unpleasant appearance to the mushrooms. The spores emitted may include new genotypes likely to attack wood or trees. Spore allergy is one of the most important limiting factors for the large scale cultivation of this species. Different approaches are being adopted at IIHR for the production of commercial sporeless/low-sporing strains of Pleurotus to alleviate the spore allergy problem. Attempts were made during the present investigation to produce sporeless or low-sporing mutants through u.v. mutation. Mutation of the mycelium did not yield the desired results. Mutation of the spores of Pleurotus sajor-caju yielded an extremely low-sporing mutant after 75 min exposure. The character has been found to be stable for more than 10 generations of subculturing.     

Pycnogenol® and vitamin E inhibit ethanol‐induced apoptosis in rat cerebellar granule cells

Pycnogenol® (PYC), a patented combination of bioflavonoids extracted from the bark of French maritime pine (Pinus maritima), scavenges free radicals and promotes cellular health. The protective capacity of PYC against ethanol toxicity of neurons has not previously been explored. The present study demonstrates that in postnatal day 9 (P9) rat cerebellar granule cells the antioxidants vitamin E (VE) and PYC (1) dose dependently block cell death following 400, 800, and 1600 mg/dL ethanol exposure (2) inhibit the ethanol‐induced activation of caspase‐3 in the same model system; and (3) reduce neuronal membrane disruption as assayed by phosphatidylserine translocation to the cell surface. These results suggest that both PYC and VE have the potential to act as therapeutic agents, antagonizing the induction of neuronal cell death by ethanol exposure. © 2004 Wiley Periodicals, Inc. J Neurobiol 59: 261–271, 2004