The PR1 family of pathogenesis-related proteins from tobacco (Nicotiana tabacum L.) leaves is induced by a variety of pathogenic and chemical agents and is associated with resistance to tobacco mosaic virus. The majority of the PR1 proteins did not copurify with mesophyll protoplasts (the major cell type of the leaf) isolated from tobacco mosaic virus-infected N. tabacum cv. Xanthi-nc leaves. H...

In order to understand the response of tobacco to salt stress, antioxidant enzyme activities, plant biomass and ion content were analyzed in two oriental tobacco genotypes (Basma 31 and SPT 406). Tobacco plants were exposed to 0, 50, 100, 150 and 200 mM NaCl for 12 days. The fresh and dry weight as well as shoot and root length of Basma 31 were greater than those of SPT 406 under increasing sal...

The microbiological composition of tobacco products was studied using culture and chemical analysis (of tobacco leaves) or chemical analysis only (tobacco and tobacco smoke). The chemical analyses utilized gas chromatography-tandem mass spectrometry for determining 3-hydroxy fatty acids, muramic acid, and ergosterol as markers of respectively lipopolysaccharide (LPS), peptidoglycan, and fungal ...

The radioactivity in tobacco leaves collected from 15 different regions of Greece and before cigarette production was studied in order to find out any association between the root uptake of radionuclides from soil ground by the tobacco plants and the effective dose induced to smokers from cigarette tobacco due to the naturally occurring primordial radionuclides , such as 226Ra and 210Pb of the ...

Resistance to virus infections in higher vertebrates is mediated in part through catalysis of RNA decay by the, interferon-regulated 2-5A system. A functional 2-5A system requires two enzymes, a 2-5A synthetase that produces 5'-phosphorylated, 2',5'-linked oligoadenylates (2-5A) in response to double-stranded RNA, and the 2-5A-dependent RNase L. We have coexpressed these human enzymes in transg...

In pathogen-infected or wounded tobacco plants, the activation of wound-induced protein kinase (WIPK), a tobacco mitogen-activated protein kinase, has been implicated in the defense response. However, no endogenous signal responsible for the activation has been identified. A WIPK-activating substance was isolated from tobacco leaves and identified as (11E,13E)-labda-11,13-diene-8alpha,15-diol, ...

Tobacco glycoprotein (TGP)' is a brown, iron-containing substance of mol wt ca. 18,000 isolated from saline extracts of flue cured tobacco leaves by ammonium sulfate fractionation, chromatography on Sephadex G-25, and continuous flow, preparative electrophoresis on alkaline polyacrylamide gel. 12 of 31 volunteers (6/15 smokers and 6/16 nonsmokers) exhibited immediate cutaneous hypersensitivity ...

Photoacclimation was studied in tobacco leaves (Nicotiana tabacum cv Xanthi) infected with two strains of tobacco mosaic virus (TMV) and grown under different light and nitrogen nutrition regimes. Photosynthetic acclimation measured by the quantum yield and the maximum rate in saturating light of CO2-saturated photosynthesis was impaired to a greater extent in tobacco leaves infected with TMV s...

Flue-curing is a post harvest conditioning process which strongly affects the tobacco leaf chemistry, and consequently the chemical properties of tobacco smoke. Several studies identified the major changes in tobacco chemistry occurring during flue-curing. It is not known how flue-curing contributes to changes in bioactivity of cigarette smoke condensate (CSC). In this study, tobacco leaves col...