Identification of vitellogenic Atlantic blue marlin (Makaira nigricans) from muscle samples using an ELISA for vitellogenin-derived yolk proteins

The purpose of this study was to develop a direct sandwich enzyme-linked immunosorbent assay (ELISA) for vitellogenin-derived yolk proteins (VDYP) in muscle tissue of pelagic Atlantic blue marlin. Gravid ovaries were extracted with physiologic buffer, and purification steps by chromatography were monitored with a cross-reactive mouse monoclonal antibody produced to swordfish (Xiphias gladius Linnaeus, 1758) VDYP. A polyclonal goat antiserum was produced to the enriched VDYP from which specific IgG was purified by affinity chromatography, using immobilized VDYP as the immunoadsorbent. A direct sandwich ELISA was developed using the purified IgG for both capture and detection of the VDYP in standard samples up to a concentration of 1000 ng/ml, and in physiologic buffer-extracted muscle tissue of test samples, using biotin-streptavidin- peroxidase technology. The assay distinguished vitellogenic from non- vitellogenic females and males in extracts of muscle tissue from 27 specimens collected from different areas of the western North Atlantic Ocean during May- September, 2002-2003. The assay for VDYP, and a second for the fish androgen 11- ketotestosterone are in use to indicate gender of electronically-tagged blue marlin from biopsy samples taken just before fish release

Phytoplasmas: an update

A summary of the research carried out on phytoplasma-associated diseases 50 years after their discovery is presented. The great majority of the research was devoted to classification and differentiation of these prokaryotes by molecular and bioinformatic tools applied to specific phytoplasma genes. The availability of a robust classification system has greatly facilitated phytoplasma identification leading to an increased knowledge of plant diseases worldwide. Scientific knowledge on phytoplasma biology still needs to be improved to allow better management solutions to reduce the impact of these diseases in agricultural and natural environments