5 research outputs found
The effect of methanol and dioxan on the rates of the β-galactosidase-catalysed hydrolyses of some β-d-galactopyranosides: rate-limiting degalactosylation. The pH-dependence of galactosylation and degalactosylation
No full textpH- and Magnesium Ion-Dependence of the Hydrolyses of β-d-Galactopyranosyl Pyridinium Salts Catalysed by Escherichia coli β-Galactosidase
No full textArtefactual Origins of Cyclic AMP in Higher Plant Tissues
No full textA highly sensitive radioimmunoassay has been used to determine the levels of adenosine 3′,5′-cyclic monophosphate (cAMP) in five higher plants (Lactuca sativa, Helianthus annuus, Oryza sativa, Pinus pinaster, Nicotiana tabacum). Particular attention was paid to the three main sources of errors in the characterization of cAMP in plants: presence of interfering substances in plant tissues; possible artefactual formation of cAMP from endogenous ATP during extraction, purification, and assay; and microbial origin of cAMP. In all the tested tissues, the cAMP level was below the detection limit of 0.5 picomole per gram fresh weight, a value much lower than those reported for similar materials of the same species in many previous studies. This result is not in favor of cAMP-dependent regulations in higher plants
