Abstract
Isozyme patterns in three taxa, Oncomelania nosophora (collected from Japan), O. formosana (from Formosa), and O. quadrasi (from the Philippines), were compared by discontinuous electrophoresis with 5% polyacrylamide gel. Among 16 enzymes examined, malate dehydrogenase (MDH), esterase (Est), and glucosephosphate isomerase (GPI) showed significantly high enzyme activities, but lactate dehydrogenase (LDH), malic enzyme (ME), xanthine dehydrogenase (XDH), hexokinase (HK), alkaline phosphatase (AIP) and asparate aminotransferase (GOT) showed very low activities under the experimental conditions used. Band mobility was highest in leucine aminopeptidase (LAP) followed by alcohol dehydrogenase (ADH), phosphoglucomutase (PGM), acid phosphatase (AcP), isocitrate dehydrogenase (lDH), AIP, GOT, HK, glucose-6-phosphate dehydrogenase (G6PD), LDH, aldehyde oxidase (Aldox), GPI, XDH, MDH, and ME. These enzymes demonstrated a single band (LAP, AcP, AIP, LDH, GPI, and ME) or 2－3 bands (ADH, Aldox, PGM, G6PD, MDH), but at least 10 isozyme bands were observed in Est. It is suggested that nosophora, formosana and quadrasi are closely related to each other as a species complex.
