Proteins Associated with Adaptation of Cultured Tobacco Cells to NaCl.

Cultured tobacco cells (Nicotiana tabacum L. cv Wisconsin 38) adapted to grow in medium containing high levels of NaCl or polyethylene glycol (PEG) produce several new or enhanced polypeptide bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The intensities of some of the polypeptide bands (molecular weights of 58, 37, 35.

Adaptation of Tobacco Cells to NaCl.

Cell lines of tobacco (Nicotiana tabacum L. var Wisconsin 38) were obtained which are adapted to grow in media with varying concentrations of NaCl, up to 35 grams per liter (599 millimolar). Salt-adapted cells exhibited enhanced abilities to gain both fresh and dry weight in the presence of NaCl compared to cells which were growing in medium without NaCl (unadapted cells).

Quantitative correlations of biological activities of dactinomycin analogs and methotrexate derivatives with van der Waals volume.

The biological activities namely the ability to bind with DNA base pairs and the in vitro inhibition of human lymphoblastic leukemia cells of certain C-7- and N2-substituted dactinomycin (actinomycin D, AMD) analogs, and the growth inhibitory activity of a series of side chain substituted methotrexate (MTX) derivatives against L 1210 mouse leukemia cells in culture and their binding affinity for dihydrofolate reductase (DHFR) enzyme extracted from this system and L. casei are found to be significantly correlated with van der Waals volume of the substituents. In case of MTX derivatives, not only the side chain substituted analogs but certain ring substituted analogs, too, are shown to have their different activities dependent upon the Vw of the substituents.

Correlation of biological activities of mesoionic and benz-fused mesoionic xanthine analogs with van der Waals volume and molecular connectivity.

The adenosine cyclic 3',5'-monophosphate (c-AMP) phosphodiesterase (PDE) inhibitory activity of a series of mesoionic 1,3,4-thiadiazolopyrimidines and of a group of benz-fused mesoionic xanthine analogs are found to be significantly correlated with the van der Waals volume (VW) of the substituents or the first order valence connectivity index (1 chi V) of the molecule. From the correlating equations it is observed that the size of the substituents at certain positions, of pyrimidine ring particularly, in the molecule are determinative to the activity. Further based on these equations it may be suggested that PDE inhibition by this class of drugs involves either hydrophobic interaction or van der Waals type of interaction.

Mutagenesis of Erwinia carotovora subsp. carotovora with bacteriophage Mu d1 (Apr lac cts62): construction of his-lac gene fusions.

The bacteriophage Mu d1(Apr lac cts62 ) obtained from an Escherichia coli double lysogen carrying the defective Mu d1 phage and a Mu-P1 hybrid phage was utilized as a vector for phage mutagenesis in Erwinia carotovora subsp. carotovora. Among ampicillin-resistant transductants.

A quantitative analysis of steric and hydrophobic effects in ribonucleoside diphosphate reductase inhibition by thiosemicarbazones.

Ribonucleoside diphosphate reductase (RDR) inhibitory activity of 2-formylpyridine and 1-formylisoquinoline thiosemicarbazones is quantitatively analysed in relation to a steric parameter (van der Waals volume, VW) and the hydrophobic parameter logP. The activity is found to be significantly correlated with VW and very poorly with logP. On the basis of this, it is inferred that RDR inhibition by thiosemicarbazones is very sensitive to steric effects and is little influenced by the hydrophobic character of the molecules.

OSAR studies on 4-hydroxyquinoline-3-carboxylic acids as inhibitors of cell respiration using molecular connectivity and van der Waals volume.

The enzyme inhibition activities of 4-hydroxyquinoline-3-carboxylic acids against three isolated enzyme systems namely mitochondrial malate dehydrogenase, cytoplasmic malate dehydrogenase, and skeletal muscle lactate dehydrogenase, all involved in respiratory pathway, are found to be significantly correlated with first-order valence molecular connectivity (1 chi v) and van der Waals volume (Vw). The correlations obtained provide much simple rationale to design more active congeners and facilitate the prediction of activity of new compounds.

Solutes contributing to osmotic adjustment in cultured plant cells adapted to water stress.

Osmotic adjustment was studied in cultured cells of tomato (Lycopersicon esculentum Mill cv VFNT-Cherry) adapted to different levels of external water potential ranging from -4 bar to -28 bar. The intracellular concentrations of reducing sugars, total free amino acids, proline, malate, citrate, quaternary ammonium compounds, K(+), NO(3) (-), Na(+), and Cl(-) increased with decreasing external water potential. At any given level of adaptation, the maximum contribution to osmotic potential was from reducing sugars followed by potassium ions.

Clonal variation for tolerance to polyethylene glycol-induced water stress in cultured tomato cells.

Cell clones were isolated from a population of cultured tomato (Lycopersicon esculentum Mill cv VFNT-cherry) cells and their tolerance to polyethylene glycol (PEG)-induced water stress was measured. Considerable variation for tolerance among the clones was found. Tolerance differences between clones appeared to be spontaneous and were different from tolerance differences between adapted and unadapted cells.

QSAR studies on psychotomimetic phenylalkylamines.

Attempts have been made to correlate hyperthermic potencies in rabbits and LSD-like effect in rat of a series of phenylisopropylamines (amphetamines) with physico-chemical parameters. In case of 2,4,5-trisubstituted analogs, hyperthermic potencies are found to be well correlated parabolically with the hydrophobic parameter pi. However, for the same series, the LSD-like effect is found to be related with pi in combination of steric parameter of 4-substituent.

Growth and water relations of cultured tomato cells after adjustment to low external water potentials.

Cultured cells of tomato, Lycopersicon esculentum Mill. cv VFNT-cherry, have been selected for resistance to water stress (low water potential) imposed by the addition of polyethylene glycol to the culture medium. The ability of nonselected cells to grow in media with low water potentials changes dramatically with the age of the cells (with respect to days following inoculation) whereas there is little effect of the age of selected cells on growth over the same media water potentials.

Characteristics of cultured tomato cells after prolonged exposure to medium containing polyethylene glycol.

Cell lines of tomato (Lycopersicon esculentum Mill., cv. VFNT-Cherry) have been isolated, which are capable of growing in media containing polyethylene glycol (PEG) 6000 with water potentials as low as -15 or -22 bar.

Amebic peritonitis secondary to amebic liver abscess.

A series of 19 patients who had amebic peritonitis secondary to rupture of an amebic liver abscess is presented. This represents 2.4% of the patients treated for ALA during an 18.

Association of Formation and Release of Cyclic AMP with Glucose Depletion and Onset of Chlorophyll Synthesis in Poterioochromonas malhamensis.

Depletion of glucose from the culture medium by Poterioochromonas malhamensis results in cessation of growth and accumulation of cyclic adenosine 3':5'-monophosphate (cAMP), followed by formation of chlorophyll and an increase in extracellular cAMP. Readdition of glucose to the culture medium causes P. malhamensis to release its intracellular cAMP into the medium.

Growth characteristics of NaCl-selected and nonselected cells of Nicotiana tabacum L.

A cell line of Nicotiana tabacum L. var. Wisconsin 38 was selected (S-10 cells) which is capable of growth in medium containing 10 g liter(-1) NaCl.

Effect of nitrogen starvation on the level of adenosine 3',5'-monophosphate in Anabaena variabilis.

Low levels of adenosine 3',5'-monophosphate (cyclic AMP) were detected in the cyanobacterium Anabaena variabilis using a protein binding assay and two radioisotopic labelling methods. The basal concentration of intracellular cyclic AMP ranged from 0.27 pmol/mg protein in A.

Synthesis and processing of maize storage proteins in Xenopus laevis oocytes.

Xenopus oocytes injected with zein mRNAs efficiently synthesized maize storage proteins for prolonged periods. Under optimal conditions, zein was synthesized at 3 ng/hr and represented approximately 10% of the total protein synthesized in the oocyte. The mRNA from the normal maize inbred line directed synthesis of all the major zein components; however, products of mRNA from the opaque-2 mutant did not contain the largest zein component.

Management of thoracic amebiasis.

The thoracic complications of amebiasis frequently necessitate surgical intervention. Experience with 28 patients is presented. Involvement included the pleura in 19 patients, the lungs in 10, and the pericardium in five.