Fatty acid compositions in growing and resting cells of several strains of Pseudomonas putida (P8, NCTC 10936, and KT 2440) were studied, with a focus on alterations of the saturation degree, cis-trans isomerization, and cyclopropane formation. The fatty acid compositions of the strains were very similar under comparable growth conditions, but surprisingly, and contrary to earlier reports, tran...

PURPOSE In the battle against cancer discovery of new and novel chemotherapeutic agent demands extreme obligation. Development of anticancer compounds with higher potency and reduced side-effects is timely and challenging. EXPERIMENTAL DESIGN A small series of fourteen diastereomeric β-lactams (seven pairs) were synthesized through multi-step process exploring [2+2] ketene-imine cycloaddition...

Photoactivation of the visual rhodopsin, a prototypical G protein-coupled receptor (GPCR), involves efficient conversion of the intrinsic inverse-agonist 11-cis-retinal to the all-trans agonist. This event leads to the rearrangement of the heptahelical transmembrane bundle, which is thought to be shared by hundreds of GPCRs. To examine this activation mechanism, we determined the x-ray crystall...

To evaluate the practical value of natural beta-carotene (NbetaC) and to elucidate the apparent discrepancy between epidemiological observations and intervention trials on the role of beta-carotene (betaC) in tumor prevention, the genotoxicity and the antigenotoxicity of NbetaC and synthetic betaC crystal (SbetaCC) stereoisomers were studied comparatively using chromosome aberration analysis an...

The metabolism of the stereomeric cyclic glycerol acetals of [1-(14)C]hexadecanal was studied in myelinating rat brain. It was found that the four isomers, cis- and trans-2-pentadecyl-5-hydroxy-1,3-dioxanes and cis- and trans-2-pentadecyl-4-hydroxymethyl-1,3-dioxolanes, were utilized by the tissue at different rates. The acetals were primarily metabolized via a ring-opening mechanism leading to...

The title compound, C(26)H(37)NO(5), was the reaction product of hellebrigenin with N,N-dimethyl-formamide. It consists of three cyclo-hexane rings (A, B and C), one five-membered ring (D) and one dihydro-pyran ring (E). The stereochemistry of the ring junctions is is A/B cis, B/C trans, C/D cis and C/E trans. The cyclo-hexane rings A, B and C have chair conformations. Both the five-membered ri...