Carlo Callegarini

Biochemical characteristics of red mullet of the central mediterranean

Abstract 1. 1. Electrophoretic and isoeletric focusing methods were utilized to differentiate the two red mullet species normally present in the Adriatic and central Mediterranean (Mullus barbatus and M. surmuletus). 2. 2. Several protein systems were studied: lactate dehydrogenase (LDH, EC 1.1.1.27), malate dehydrogenase (MDH, EC 1.1.1.37) and soluble lens proteins. 3. 3. Species-specific electrophoretic and isoelectrophoretic patterns were found in LDH and lens proteins, whereas the MDH of the two species exhibited the same pattern with both techniques. 4. 4. Of the protein systems analysed so far, LDH and lens proteins were found to be useful for our purposes: as they exhibit different patterns in the two species in question, they permit species identification even during the stages when this is impossible on morphological grounds. 5. 5. Some hypotheses for further study are put forward.

Electrophoretic and isoelectrophoretic characteristics of hemoglobins of Italian ictalurids

Electrophoretic and isoelectrophoretic behaviour of the hemoglobins of Italian freshwater Ictalurids was analysed. Multiple and polymorphic hemoglobin patterns were found in Ictalurus sp. (I. nebulosus nebulosus?, I. melas?); multiple and monomorphic patterns in I. n. marmoratus and I. punctatus. Hypotheses are advanced for further investigation of the question.

Soluble eye lens proteins of Italian ictalurids

Abstract 1. 1. Soluble eye lens proteins of three species of Italian freshwater ictalurids were analyzed: Ictalurus sp., I. nebulosus marmoratus and I. punctatus . 2. 2. The electrophoretic and isoelectric focusing patterns were compared. 3. 3. Both techniques revealed species-specific patterns. I . sp. and I. nebulosus marmoratus exhibited very similar patterns, I. punctatus a quite distinct one. 4. 4. Some hypotheses warranting further investigation of the subject were proposed.

Biochemical characteristics of mugilids in the lagoons of the Po delta

Abstract Electrophoretic method has been applied to biochemical classification of Mugilids in the Lagoons of the Po delta. Among the various proteins analysed the one which turned out to be the most useful was the lactate dehydrogenase enzyme (LDH) because it presents different patterns in the five species living in the above mentioned lagoon and does not show any variations in the course of ontogenesis. This caracteristic makes it possible to identify stocks of fry to be put into closed waters for subsequent cultivation. Moreover this method allows one to make certain phylogenetic speculations with regard to the origin of these species.

A new form of alpine salamander

Abstract Salamanders collected near Asiago, north of Vicenza (North-eastern Italy), were studied. From their morphological and embryological characteristic and electrophoretic patterns of haemoglobins and LDH isoenzymes they were interpreted as a possible new subspecies of Salamandra atra Laur.

Isoenzymes and Fish Phylogenesis

Abstract A survey has been made of the information available about the evolutionary characteristics of the enzyme lactic-dehydrogenase in teleosts. In this superorder the subunits of this enzyme with a characteristic tetramer structure are coded at the level of at least three genetic loci. The activity of these loci and the tetrameric structure lead to multi-molecular forms called isoenzymes. The oldest vertebrates probably possessed only one locus for coding enzyme subunits and this situation can still be observed in petromyzoniformes. In mixinoids and in chondroichthyes there are two active loci. In osteichthyes on the other hand there are at least three active loci. Speculations are made concerning the moment of duplication of the hypothetical ancestral gene and of at least one of the genes derived from it. Some data are presented which appear to indicate the presence of a third active locus even in Sarcopterygii, ancestors of the upper vertebrates.