A mutant of Escherichia coli lacking leucyl,phenylalanyl-tRNA:protein leucyltransferase, EC 2.3.2.6) exhibited several abnormal growth characteristics relative to the wild type or a revertant when grown with glycerol as a carbon source. All three strains were auxotrophic for proline. The mutant required higher levels of this amino acid than did the other strains to attain a normal growth yield ...

in this study, the effect of drought and different concentrations of silicon was examined on seed yield, essential oil percentage and physio-chemicals properties in fennel plant. the experimental design was a split plot with three irrigation regimes: irrigation at 100, 70 and 40 percent of fc comprising the main treatments, and five levels of silicon foliar sprays (0, 2.5, 5, 7.5 and 10 mm) as ...

An understanding of the mechanisms that determine plant response to reduced water availability is essential to improve water-use efficiency (WUE) of stone fruit crops. The physiological, biochemical and molecular drought responses of four Prunus rootstocks (GF 677, Cadaman, ROOTPAC 20 and ROOTPAC(®) R) budded with 'Catherina' peach cultivar were studied. Trees were grown in 15-l containers and ...

The effect of drought stress at supraoptimal temperature on free proline and polyamine levels was compared in wild type and transgenic soybean (Glycine max cv. Ibis) plants having increased proline levels. Since glutamate and arginine are precursors of both proline and polyamines, it was assumed that the genetic manipulation of proline levels would also affect the polyamine levels. The proline ...

G protein-coupled receptors (GPCRs) contain a number of conserved proline residues in their transmembrane helices, and it is generally assumed these play important functional and/or structural roles. Here we use unnatural amino acid mutagenesis, employing α-hydroxy acids and proline analogues, to examine the functional roles of five proline residues in the transmembrane helices of the D2 dopami...

Clinical observations indicate that in chronic obstructive pulmonary disease patients, the long-acting muscarinic antagonist tiotropium delays decline in airway function, suggesting that cholinergic mechanisms contribute to long-term structural changes. Human lung fibroblasts express muscarinic receptors and the present study aimed to explore their role in controlling collagen synthesis. MRC-5,...

Excised leaves were incubated at various water contents to determine the effect of water status on amino acid composition. Considerable proteolysis took place during incubation with a resultant increase in each amino acid in the non-protein fraction. However, serine, proline, gamma-aminobutyric acid and methyleysteine sulfoxide were the only amino acids in which there was an accumulation (i.e.,...

While intracellular proline accumulation in response to various stress conditions has been investigated in great detail, the biochemistry and physiological relevance of proline degradation in plants is much less understood. Moreover, the second and last step in proline catabolism, the oxidation of δ(1)-pyrroline-5-carboxylic acid (P5C) to glutamate, is shared with arginine catabolism. Little in...

Treatment of rats with the beta-agonist isoproterenol causes a dramatic increase in a series of proteins rich in proline (proline-rich proteins) in the parotid glands (Muenzer, J., Bildstein, C., Gleason, M., and Carlson, D. M. (1979) J. Biol. Chem. 254, 5623, 5629). These proteins which contain about 43% proline, comprise more than 50% of the total soluble protein of glands of rats treated wit...