1. Leishmania donovani promastigotes labelled for 2 h with 32p, incorporated radioactivity into at least 21 different proteins, as determined by SDS/polyacrylamide-gel electrophoresis. Pulse-chase studies with 32P, demonstrated that the labelled proteins were in a dynamic state: some radiolabelled proteins rapidly disappeared and others appeared after the chase. The possibility of an ectokinase...

As a first step in determining the molecular mechanism of membrane fusion stimulated by GTP in rough endoplasmic reticulum (RER), we have looked for GTP-binding proteins. Rough microsomes from rat liver were treated for the release of ribosomes, and the membrane proteins were separated by SDS/polyacrylamide-gel electrophoresis. The polypeptides were then blotted on to nitrocellulose sheets and ...

In a previous paper' the authors described their experience of the 32P uptake test in the diagnosis of intraocular malignancies and discussed some of the factors affecting the uptake. The 32p test is based on the differential accumulation of radioactive phosphorus between neoplastic and non-neoplastic tissue following an intravenous injection of the isotope. Counts are recorded from a site on t...

Dolichyl [beta-32P]pyrophosphate ([beta-32P]Dol-P-P) has been prepared chemically to study Dol-P-P phosphatase in calf brain. Calf brain microsomes catalyze the enzymatic release of 32Pi from exogenous [beta-32P]Dol-P-P by a bacitracin-sensitive reaction. [32P]Pyrophosphate was not detected with the water-soluble product even when 1 mM sodium pyrophosphate was added to impede pyrophosphatase ac...

Summtiizary. Primary roots of solution--grown, 5-day-old or 6-day-old seedlings of corn (Zea mays L.) 10 to 14 cm in length were used to study radial salt trtansport. Measurements were made of the volume of root pressure exudation, salt concentration of the exudate, and rate of salt movement into the xylem exudate. The 32p uptake, 09 consumption, and dehydrogenase activity of the root cortex an...

In this study, we have used photoaffinity labeling by [32P]azido-GTP as well as [32P]ADP-ribosylation by pertussis toxin (PT) and cholera toxin (CT) to identify GTP-binding proteins associated with mouse T-lymphoma plasma membranes. Our results indicate that GP85 (CD44) can be photoaffinity labeled by [32P] azido-GTP and [32P]ADP-ribosylated by both PT and CT. Using purified GP85 (CD44) obtaine...

We have previously described a 32P assay for the detection and quantitation of aromatic carcinogen:DNA adducts (R. C. Gupta et al., Carcinogenesis (Lond.), 3: 1081-1092, 1982). The method entails enzymatic digestion of DNA to deoxynucleoside 3'-monophosphates which are then converted to deoxynucleoside 3',5'-[5'-32P]diphosphates by T4 polynucleotide kinase-catalyzed 32P transfer from adenosine ...