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17 alpha-Hydroxylase/C17-20-lyase (P450 17, CYP 17) and 5 alpha-reductase are the key enzymes in androgen biosynthesis and targets for the treatment of prostate cancer and benign prostatic hyperplasia. In the search of inhibitors for both enzymes, 23 pregnenolone- or progesterone-based steroids were synthesized bearing an oxime group connected directly or via a spacer to the steroidal D-ring. Tested for inhibition of human and rat P450 17, some pregnenolone (9, 11, 14) and a series of progesterone compounds (17-20) turned out to be highly active inhibitors of the human enzyme. The most active compound was Z-21-hydroxyiminopregna-5, 17(20)-dien-3 beta-ol (9) showing K(i) values of 44 and 3.4 nM for the human and rat enzymes, respectively, and a type II UV-difference spectrum indicating a coordinate bond between the oxime group and the heme iron. In contrast to the pregnenolones which showed no inhibition of 5 alpha-reductase isozymes 1 and 2, the progesterones 16, 17, 20, 21, and 23 showed marked inhibition, especially toward the type 2 enzyme. Compounds 17 and 20 were identified as potent dual inhibitors of both P450 17 and 5 alpha-reductase. Tested for selectivity, the most potent P450 17 inhibitors 9, 10, and 14 showed no or only marginal inhibition of P450 arom, P450 scc, and P450 TxA(2). Selected compounds were tested for inhibition of the target enzymes using whole-cell assays. Compounds 9-11 strongly inhibited P450 17 being coexpressed with NADPH-P450 reductase in E. coli cells, and 16, 20, and 23 markedly inhibited 5 alpha-reductase expressed in HEK 293 cells. Tested for in vivo activity, 9 (0.019 mmol/kg) decreased the plasma testosterone concentration in rats after 2 and 6 h by 57% and 44%.

1 Binding affinity at the [ 3 H]-BK binding site and activity as inositol phosphate (IP) production by the peptide bradykinin (BK) and the nonpeptide FR190997 were studied at wild-type or pointmutated human B 2 receptors (hB 2 R) expressed in CHO cells. 2 The effect of the following mutations were analyzed: E47A (TM1), W86A and T89A (TM2), I110A, L114A and S117A (TM3), T158A, M165T and L166F (TM4), T197A and S211A (TM5), F252A, W256A and F259A (TM6), S291A, F292A, Y295A and Y295F (TM7), and the double mutation W256A/Y295F. 3 As the wild-type receptor-binding affinity of FR190997 was 40-fold lower than BK, whereas their agonist potency was comparable, both agonists produced similar maximal effects (E max ). Mutations were evaluated as affecting the affinity and/or efficacy of FR190997 compared with BK. 4 Two mutations were found to impair the agonist affinity of both agonists drastically: W86A and F259A. BK agonist affinity (pEC 50 ) was reduced by 1400-and 150-fold, and that of FR190997 was reduced by 400-and 25-fold, at the W86A and F259A mutant B 2 receptors, respectively. 5 Contrary to BK, the affinity of FR190997 was selectively decreased at I110A, Y295A, and Y295F mutants (410 3 -fold), and a different efficacy was measured at the Y295 mutants, FR190997 being devoid of the capability to trigger IP production at Y295A mutant. 6 L114A, F252A, and W256A selectively impaired the efficacy of FR190997, whereas its binding affinity was not affected. As a consequence, FR190997 behaved as a high-affinity antagonist in blocking the IP production induced by BK. 7 The lack of capability of FR190997 to activate or to bind the double mutant W256A/Y295F suggests that these residues are part of the same binding site, which is also important for receptor activation by the nonpeptide ligand. 8 Overall, by means of mutational analysis, we indicate an hB 2 R recognition site for the nonpeptide agonist FR190997 (between TM3, 6, and 7), different from that of BK, and show that in the same binding crevice some mutations (L114, W256, and F252) are selectively responsible for the agonist properties of only FR190997.

Over the past 12 years, the lichen trait database LIAS light as a component of the LIAS information system, has grown to a considerable pool of descriptive data based on 71 different qualitative, quantitative, and text characters, for nearly 10.000 lichen taxa, being phylogenetically arranged according to the MycoNet classification. It includes information on morphological, ecological and chemical traits. Multilinguality or internationalization options have become a central challenge of the project. At present, 18 language versions of the database and web interface exist. LIAS light data are accessible in DELTA format and to be used locally and web browser-based, via NaviKey applet. Key words Identification, trait database, characters, biodiversity informatics Project features and concepts for the futureFor the purpose of giving access to treated taxa, monographic and floristic treatments are often assigned with traditional dicho-or polytomous identification keys. Until today, such keys have proven to be of highest value as they mostly provide identification criteria optimized for a specific set of taxa or an area. Nevertheless, the growing use of the internet as well as the need of open access to information and knowledge on biodiversity at a higher or global scale has led to an increased use of internet-related technologies for identifying taxa (Hagedorn et al.