Contribution of sponge genes to unravel the genome of the hypothetical ancestor of Metazoa (Urmetazoa).

Recently the term Urmetazoa, as the hypothetical metazoan ancestor, was introduced to highlight the finding that all metazoan phyla including the Porifera (sponges) are derived from one common ancestor. Sponges as the evolutionarily oldest, still extant phylum, are provided with a complex network of structural and functional molecules. Analyses of sponge genomes from Demospongiae (Suberites domuncula and Geodia cydonium), Calcarea (Sycon raphanus) and Hexactinellida (Aphrocallistes vastus) have contributed also to the reconstruction of the evolutionary position of Metazoa with respect to Fungi. Furthermore, these analyses have provided evidence that the characteristic evolutionary novelties of Metazoa, such as the extracellular matrix molecules, the cell surface receptors, the nervous signal transduction molecules as well as the immune molecule existing in Porifera, share high sequence and in some aspects also functional similarities to related polypeptides found in other metazoan phyla. During the transition to Metazoa new domains occurred; as one example, the formation of the death domain from the ankyrin is outlined. In parallel, domanial proteins have been formed, such as the receptor tyrosine kinases. The metazoan essentials have been defined by analyzing and comparing the sponge sequences with the related sequences from the metazoans Homo sapiens, Caenorhabditis elegans and Drosophila melanogaster, the fungus Saccharomyces cerevisiae and the plant Arabidopsis thaliana. The data revealed that those sponge molecules grouped to cell adhesion cell recognition proteins are predominantly found in Protostomia and Deuterostomia while they are missing in Fungi and Viridiplantae. Moreover, evidence is presented allowing the conclusion that the sponge molecules are more closely related to the corresponding molecules from H. sapiens than to those of C. elegans or D. melanogaster. Especially surprising was the finding that the Demospongiae are provided with elements of adaptive immunity.

Compounds with positive inotropic activity, IV: Synthesis of N-methoxyquinolinium salts and their effects in heart muscles.

N-Methoxyquinolinium salts 3 are prepared as potential cardiotonic agents by alkylation of the corresponding N-oxides 2 synthesized by two different methods. 1. Oxidation of some quinoline derivatives 1 using 30% H2O2 or 3-chloroperbenzoic acid. 2. Nitration of the quinoline-N-oxides 2a, 2c, and 2m. Preparation of 2h and 2k requires subsequent nucleophilic ipso-substitution of the nitro group. The compounds 3 are tested for positive inotropic activity on isolated left atria and papillary muscles from guinea-pig. Structure activity relationships indicate that the effect depends on the N-methoxy group of the target compounds as well as on the presence of an electron-withdrawing substituent.