Secretion and Uptake of 14C Proteins by Fat Body of Calpodes ethlius Stoll. (Lepidoptera, Hesperiidae)

Insect fat body from larvae of Calpodes ethlius synthesised proteins in vitro , some of which were secreted into the medium. ¹⁴C leucine was incorporated into fat-body proteins and the released proteins were characterised by electrophoresis and immunodiffusion. The released proteins included the three main proteins normally found in larval hemolymph and fat body. Larval fat body in the main synthetic phase of development did not sequester these ¹⁴C-labelled proteins when incubated with them in vitro or when they were injected into mid-instar larvae. In contrast, these proteins were sequestered by fat-body cells undergoing pupation.
The conclusion is that larval fat-body cells in the main synthetic phase selectively exclude proteins synthesised in vitro by fat body of the same age. During pupal development the fat body absorbs proteins it secreted at an earlier age.     

Macromolecules in brachiopod shells: characterization and diagenesis

An immunological investigation was conducted of soluble intra-crystalline macromolecules isolated from living and fossil brachiopod shells, which had previously been used for an immunologically based study of phylogeny (serotaxonomy). The soluble intra-crystalline macromolecules comprised 0.03% by weight of the extant shell material. Bulk analysis and gel electrophoresis indicated that the organic material is predominantly glycoprotein, and contains up to 30% by weight carbohydrate. Treatment of the macromolecules with periodate and proteinase K revealed that antibodies were raised predominantly against the carbohydrate moieties. Using a specially adapted dot blot immunobinding assay (DIBA) the decay in immunological signal over geological time was determined. Pleistocene shells have lost between 99 and 99.9% of immunological reactivity, and original antigenic determinants form a declining proportion of total organic matter. It is suggested that condensation reactions between amino acids and sugars account for the rapid destruction of determinants; this has important implications for the direction of future studies on fossil macromolecules. □ Serotaxonomy, biomolecular palaeontology, glycoproteins, melanoidins, brachiopods.     

Anthocyanins in Symplocarpus foetidus (L.) Nutt. (Araceae)

The flower pigments of Symplocarpus foetidus (L.) Nutt., a sapromyophilous plant were examined and cyanidin-3-monoglucoside, cyanidin-3-rutinoside and peonidin-3-rutinoside were identified. The pigments were identified by means of paper, thin-layer and gas chromatography.