M C C Ruvolo-Takasusuki; M A Del Lama; A E E Soares
Starch gel electrophoresis of abdomen extracts from adult drones revealed the occurrence of electrophoretic variants of esterase-2 in Apis mellifera. We demonstrated an enzyme preference for 4-methylumbelliferyl butyrate as a substrate and a pattern of enzyme inhibition which suggests that it is an arylesterase. Tests demonstrated that esterase-2 has the highest heat stability among all A. mellifera esterases. The mean frequency of the Est-2S allele estimated for the five populations investigated was 9.22%. Electrophoretic analysis of worker pupae demonstrated that the heterozygous phenotype only presents an intermediate band between the fast and slow variants of this enzyme, suggesting a probable preferential association of the monomers for the formation of the dimer. Five new tests of two-point genetic linkage involving esterase-2 and other known markers permitted us to demonstrate the occurrence of gene linkage between the loci Est-2 and Est-1a, with a map distance estimated at 26.5 units.